| United States Patent Application |
20130156691
|
| Kind Code
|
A1
|
|
Goldenberg; David M.
;   et al.
|
June 20, 2013
|
Antibody Therapy
Abstract
The present invention provides a composition comprising naked humanized,
chimeric, and human anti-CEA antibodies and a therapeutic agent, which is
useful for treatment of CEA expressing cancers and other diseases, and
methods of use in treatment using this composition.
| Inventors: |
Goldenberg; David M.; (Mendham, NJ)
; Hansen; Hans J.; (Picayune, MS)
|
| Applicant: | | Name | City | State | Country | Type | Goldenberg; David M.
Hansen; Hans J. | Mendham
Picayune | NJ
MS | US
US | | |
| Assignee: |
IMMUNOMEDICS, INC.
Morris Plains
NJ
|
| Family ID:
|
34830287
|
| Appl. No.:
|
13/476157
|
| Filed:
|
May 21, 2012 |
Related U.S. Patent Documents
| | | | |
|
| Application Number | Filing Date | Patent Number | |
|---|
| | 13245330 | Sep 26, 2011 | 8216572 | |
| | 13476157 | | | |
| | 13030204 | Feb 18, 2011 | 8062636 | |
| | 13245330 | | | |
| | 12639298 | Dec 16, 2009 | 7919090 | |
| | 13030204 | | | |
| | 11932530 | Oct 31, 2007 | 7662378 | |
| | 12639298 | | | |
| | 10680734 | Oct 8, 2003 | 7803372 | |
| | 11932530 | | | |
| | PCT/US02/32307 | Oct 11, 2002 | | |
| | 10680734 | | | |
| | 60467161 | May 2, 2003 | | |
| | 60416531 | | | |
|
|
| Current U.S. Class: |
424/1.11 ; 424/133.1; 424/135.1; 424/138.1; 424/156.1; 424/85.1; 424/85.5 |
| Current CPC Class: |
A61P 37/04 20180101; A61K 51/1048 20130101; A61K 2039/505 20130101; A61K 38/164 20130101; A61K 51/1045 20130101; C07K 16/3007 20130101; A61K 38/20 20130101; A61K 31/513 20130101; A61K 38/193 20130101; A61K 31/519 20130101; A61P 31/00 20180101; A61K 38/217 20130101; A61K 51/1096 20130101; A61K 38/1816 20130101; A61K 38/168 20130101; A61K 31/704 20130101; A61K 31/555 20130101; A61K 31/4545 20130101; A61K 31/475 20130101; A61K 31/655 20130101; A61P 35/00 20180101; A61K 31/675 20130101; A61K 38/191 20130101; C07K 2317/24 20130101; A61K 38/196 20130101; A61K 31/4745 20130101; A61K 31/437 20130101; A61K 39/39558 20130101; A61K 38/164 20130101; A61K 2300/00 20130101; A61K 38/168 20130101; A61K 2300/00 20130101; A61K 38/1816 20130101; A61K 2300/00 20130101; A61K 38/191 20130101; A61K 2300/00 20130101; A61K 38/193 20130101; A61K 2300/00 20130101; A61K 38/20 20130101; A61K 2300/00 20130101; A61K 39/39558 20130101; A61K 2300/00 20130101; A61K 38/217 20130101; A61K 2300/00 20130101; A61K 38/196 20130101; A61K 2300/00 20130101 |
| Class at Publication: |
424/1.11 ; 424/156.1; 424/85.1; 424/133.1; 424/85.5; 424/135.1; 424/138.1 |
| International Class: |
A61K 39/395 20060101 A61K039/395; A61K 38/19 20060101 A61K038/19; A61K 31/655 20060101 A61K031/655; A61K 31/704 20060101 A61K031/704; A61K 38/21 20060101 A61K038/21; A61K 31/475 20060101 A61K031/475; A61K 31/519 20060101 A61K031/519; A61K 31/513 20060101 A61K031/513; A61K 31/555 20060101 A61K031/555; A61K 31/4745 20060101 A61K031/4745; A61K 51/10 20060101 A61K051/10; A61K 31/675 20060101 A61K031/675 |
Claims
1. A method for treating a CEA expressing cancer comprising: a)
administering to a subject with a CEA expressing cancer a naked Class I
monovalent anti-CEA monoclonal antibody (MAb) or antigen-binding fragment
thereof; b) administering to the subject either concurrently or
sequentially a naked Class III anti-CEA antibody or antigen-binding
fragment thereof, wherein (i) the naked Class III anti-CEA antibody or
fragment thereof is unreactive with human granulocytes; (ii) the naked
Class III anti-CEA antibody or fragment thereof has human IgG1 hinge and
constant regions; (iii) administration of the naked Class III anti-CEA
antibody or fragment thereof to a subject with a cancer that expresses
CEA antigen sensitizes the cancer to the subsequent administration of a
therapeutic agent; and c) administering to the subject either
concurrently or sequentially at least one therapeutic agent.
2. The method of claim 1, wherein the therapeutic agent is selected from
the group consisting of an antibody, an antigen-binding antibody
fragment, an immunoconjugate, a cytotoxic agent, a chemotherapeutic
agent, a radionuclide, an immunomodulator, a photoactive therapeutic
agent, an antisense oligonucleotide and a hormone.
3. The method of claim 2, wherein the therapeutic agent comprises
vincristine, doxorubicin, DTIC, cyclophosphamide, CPT-11, oxaliplatin,
gemcitabine and 5-fluorouracil/leucovorin.
4. The method of claim 2, wherein the therapeutic agent is selected from
the group consisting of vincristine, doxorubicin, DTIC, cyclophosphamide,
CPT-11, oxaliplatin, gemcitabine and 5-fluorouracil/leucovorin.
5. The method of claim 2, wherein the therapeutic agent is a naked
antibody or an immunoconjugate.
6. The method of claim 5, wherein said naked antibody or immunoconjugate
comprises a humanized, chimeric, human or murine antibody or fragment
thereof reactive with an antigen selected from the group consisting of
EGP-1, EGP-2, MUC-1, MUC-2, MUC-3, MUC-4, antigen bound by PAM4 antibody,
KC4, TAG-72, EGFR, HER2/neu, BrE3, Le-Y, A3, A33, Ep-CAM, Tn,
Thomson-Friedenreich antigens, tumor necrosis antigens, VEGF, a tumor
angiogenesis antigen, Ga 733, tenascin and fibronectin.
7. The method of claim 1, wherein the cancer is medullary thyroid
carcinoma or colon cancer.
8. The method of claim 2, wherein the cytotoxic agent is a drug or toxin.
9. The method of claim 8, wherein the drug possesses a pharmaceutical
property selected from the group consisting of antimitotic, alkylating,
antimetabolite, antiangiogenic, apoptotic, alkaloid, COX-2, and
antibiotic agents and combinations thereof.
10. The method of claim 8, wherein the drug is selected from the group
consisting of nitrogen mustards, ethylenimine derivatives, alkyl
sulfonates, nitrosoureas, triazenes, folic acid analogs, anthracyclines,
taxanes, COX-2 inhibitors, pyrimidine analogs, purine analogs,
antimetabolites, antibiotics, enzymes, epipodophyllotoxins, platinum
coordination complexes, vinca alkaloids, substituted ureas, methyl
hydrazine derivatives, adrenocortical suppressants, antagonists,
endostatin, taxols, camptothecins, doxorubicins and a combination
thereof.
11. The method of claim 8, wherein the toxin is a microbial, plant or
animal toxin selected from the group consisting of ricin, abrin, alpha
toxin, saporin, ribonuclease (RNase), DNase I, Staphylococcal
enterotoxin-A, pokeweed antiviral protein, gelonin, diphtheria toxin,
Pseudomonas exotoxin and Pseudomonas endotoxin.
12. The method of claim 2, wherein the immunomodulator is selected from
the group consisting of a cytokine, a stem cell growth factor, a
lymphotoxin, a hematopoietic factor, a colony stimulating factor (CSF),
an interferon (IFN), erythropoietin, thrombopoietin, tumor necrosis
factor (TNF), an interleukin (IL), granulocyte-colony stimulating factor
(G-CSF), granulocyte macrophage-colony stimulating factor (GM-CSF),
interferon-alpha., interferon-beta, interferon-gamma, a stem cell growth
factor designated "S1 factor," IL-1, IL-2, IL-3, IL-6, IL-10, IL-12,
IL-18 and IL-21.
13. The method of claim 2, wherein the immunomodulator comprises IL-1,
IL-2, IL-3, IL-6, IL-10, IL-12, IL-18, interferon-.gamma., TNF-.alpha. or
a combination thereof.
14. The method of claim 2, wherein the radionuclide is selected from the
group consisting of .sup.32P, .sup.33P, .sup.47Sc, .sup.59Fe, .sup.64Cu,
.sup.67Cu, .sup.75Se, .sup.77As, .sup.89Sr, .sup.90Y, .sup.99Mo,
.sup.105Rh, .sup.109Pd, .sup.111Ag, .sup.125I, .sup.131I, .sup.142Pr,
.sup.143Pr, .sup.149Pm, .sup.153Sm, .sup.161Tb, .sup.166Ho, .sup.169Er,
.sup.177Lu, .sup.186Re, .sup.188Re, .sup.189Re, .sup.194Ir, .sup.198Au,
.sup.199Au, .sup.211Pb, .sup.212Pb, .sup.213Bi, .sup.58Co, .sup.67Ga,
.sup.80mBr, .sup.99mTc, .sup.103mRh, .sup.109Pt, .sup.111In, .sup.119Sb,
.sup.161Ho, .sup.189mOs, .sup.192Ir, .sup.152Dy, .sup.211At, .sup.212Bi,
.sup.223Ra, .sup.219Rn, .sup.215Po, .sup.211Bi, .sup.225Ac, .sup.221Fr,
.sup.217At, .sup.213Bi, .sup.88Y and .sup.255Fm.
15. The method of claim 1, wherein the subject has a colon, rectal,
pancreatic, breast, ovarian, thyroid or lung cancer.
16. The method of claim 1, wherein said antibody fragment is selected
from the group consisting of a F(ab').sub.2, a Fab', a Fab, an Fv and an
scFv.
17. The method of claim 1, wherein the Class I anti-CEA antibody is MN-3
or MN-15.
18. The method of claim 1, wherein the Class III anti-CEA antibody is
MN-14.
19. The method of claim 1, wherein the Class III anti-CEA antibody is a
G1m3 allotype antibody.
20. The method of claim 1, wherein the Class III anti-CEA antibody is an
nG1m1 allotype antibody.
Description
RELATED APPLICATIONS
[0001] This application is a divisional of U.S. application Ser. No.
13/245,330, filed Sep. 26, 2011, which was a divisional of U.S.
application Ser. No. 13/030,204 (now U.S. Pat. 8,062,636), filed Feb. 18,
2011, which was a divisional of U.S. application Ser. No. 12/639,298 (now
U.S. Pat. No. 7,919,090), filed Dec. 16, 2009, which was a divisional
U.S. application Ser. No. 11/932,530 (now U.S. Pat. No. 7,662,378), filed
Oct. 31, 2007, which was a continuation of U.S. application Ser. No.
10/680,734 (now U.S. Pat. No. 7,803,372), filed Oct. 8, 2003, which
claimed the benefit under 35 U.S.C. 119(e) of U.S. Provisional
Application No. 60/467,161, filed May 2, 2003. This application also
claims priority to International Application No. PCT/US02/32307, filed
Oct. 11, 2002, which in turn claimed the benefit under 35 U.S.C. 119(e)
of U.S. Provisional Application No. 60/416,531, filed Oct. 8, 2002.
BACKGROUND OF THE INVENTION
[0002] A. Field of the Invention
[0003] The invention relates to methods of treating cancers that express
carcinoembryonic antigen ("CEA"), particularly medullary thyroid cancer
(MTC), non-medullary thyroid cancers (non-MTC), colorectal cancers,
hepatocellular carcinoma, gastric cancer, lung cancer, breast cancer and
other cancers, in which CEA is expressed, by administering an
immunological reagent comprising an antibody in combination with at least
one other therapeutic agent, such as another antibody, a chemotherapeutic
agent, a radioactive agent, an antisense oligonucleotide, an
immunomodulator, an immunoconjugate or a combination thereof. The
invention further relates to pharmaceutical compositions comprising the
immunological reagent and at least one therapeutic agent in an
unconjugated form. In particular, the invention relates to methods of
treating cancers that express CEA by administering, prior to, with or
after administering the therapeutic agent, a Class III
anti-carcinoembryonic antigen ("anti-CEA") monoclonal antibody ("MAb"),
particularly a MAb, that has the binding affinity characteristics and
specificities of corresponding murine Class III anti-CEA MAb, and more
particularly humanized, chimeric or human MAbs, that possess more of the
antigenic and effector properties of a human antibody. Particularly
useful MAbs in the method of treatment are humanized MAbs in which the
complementarity-determining regions ("CDRs") of an anti-CEA murine MAb
are grafted into the framework regions of a human antibody.
[0004] B. Background
[0005] CEA is an oncofetal antigen commonly expressed in a number of
epithelial cancers, most commonly those arising in the colon but also in
the breast, lung, pancreas, thyroid (medullary type) and ovary
(Goldenberg et al., J. Natl. Cancer Inst. 57:11-22 (1976), Shively, et
al., Crit. Rev. Oncol. Hematol. 2:355-399 (1985)). CEA was originally
thought to be a tumor-specific antigen of colorectal cancer (Gold et al.,
J. Exper. Med., 122:467 (1965)). However, it was later found to be
present in a diverse number of carcinomas, benign tumors, and diseased
tissues, as well as in normal human colon (Shively et al., Crit. Rev.
Oncol. Hematol., 2:355 (1985); von Kleist et al., Proc. Natl. Acad. Sci.
USA., 69:2492 (1972)). CEA has been shown to mediate cell-cell adhesion
through homotypic and heterotypic interactions, which in turn have
implicated a role for CEA in various aspects of tumorigenesis.
[0006] Medullary thyroid cancer (MTC) confined to the thyroid gland is
potentially curable by total thyroidectomy and central lymph node
dissection. However, disease recurs in approximately 50% of these
patients. In addition, the prognosis of patients with unresectable
disease or distant metastases is poor, less than 30% survive 10 years
(Rossi et al., Amer. J. Surgery, 139:554 (1980); Samaan et al., J. Clin.
Endocrinol. Metab., 67:801 (1988); Schroder et al., Cancer, 61:806
(1988). These patients are left with few therapeutic choices (Principles
and Practice of Oncology, DeVita, Hellman and Rosenberg (eds.), New York:
JB Lippincott Co. 1333-1435 (1989); Cance et al., Current Problems
Surgery, 22:1 (1985)). Chemotherapy has been of little value and
radiation therapy may only be used to control local disease (Cance et
al.; Tubiana et al., Cancer, 55:2062 (1985)). Thus, new therapeutic
modalities are needed to control this disease.
[0007] A useful approach to cancer therapy and diagnosis involves the use
of targeting antibodies to deliver therapeutic and diagnostic agents
directly to the site of a malignancy. Over the past decade, a wide
variety of tumor-specific antibodies and antibody fragments have been
developed, as have methods to conjugate the antibodies to therapeutic
agents, such as drugs, toxins, radionuclides, immunomodulators, such as
cytokines or other agents, and to administer the conjugates to patients
that target the tumor. However, patients treated with drugs or
radionuclides complexed with murine monoclonal antibodies (which have
been the most commonly used targeting antibodies for humans) develop
circulating human anti-mouse antibodies (HAMAs) and sometimes a
generalized immediate type-III hypersensitivity reaction to the antibody
moiety of the conjugate. But these problems have been minimized by making
these murine antibodies less immunogenic by a number of different
methods, which include making humanized, chimeric or human antibodies, by
chemically modifying the targeting antibody, such as by conjugating to
polyethylene glycol to the targeting antibody (PEGylation), or by
characterizing the situs of antigenicity in an antibody and then removing
it; e.g., Fab', F(ab).sub.2 and other antibody fragments have been used
in place of whole IgG. In addition, attempts have been made to reduce the
adverse effects of HAMA by plasmaphoretically removing HAMA from blood.
Immunosuppressive techniques also have been used to ameliorate the
adverse effect of the foreign antibody sufficiently to permit multiple
treatments with the targeting agent.
[0008] Regardless of these treatment advances, there still exists a need
to provide more effective methods of treating CEA-expressing cancers. The
present invention provides an effective therapy utilizing anti-CEA
antibodies, such as a Class III anti-CEA MAb, the murine MN-14 MAb as
defined in U.S. Pat. No. 5,874,540 and Hansen et al., Cancer, 71:3478
(1993), and a Class III anti-CEA MAb, the chimeric and humanized MN-14
MAbs as also defined in U.S. Pat. No. 5,874,540, and the NP-4 as defined
in U.S. Pat. No. 4,818,709 by Primus et al., for example, all
incorporated herein in their entirety by reference. Preferably, the Class
III anti-CEA MAb is humanized, and used in combination with a therapeutic
agent, particularly a chemotherapeutic agent, to yield an effective
therapeutic treatment for CEA expressing cancers with minimal toxicity.
Additionally, other anti-CEA antibodies, such Class II MAbs, for example,
MN-6 (see Hansen et al., above, and NP-3 (se U.S. Pat. No. 4,818,709),
and Class I MAbs, such MN-3 and MN-15 (see also Hansen et al., above)
provide effective methods of treating CEA expressing cancers. Further,
the separate administration of these two components provides enhanced
results and the versatility and the flexibility to tailor individual
treatment methods.
SUMMARY OF THE INVENTION
[0009] Contemplated in the present invention are compositions and methods
of treating medullary and non-medullary thyroid carcinomas.
[0010] The first embodiment of the present invention is a composition
comprising at least one anti-CEA monoclonal antibody (MAb) or fragment
thereof, which is preferably a Class III anti-CEA MAb or fragment, and at
least one therapeutic agent. Preferably, the antibody fragment is
selected from the group consisting of F(ab').sub.2, Fab', Fab, Fv and
scFv. Also preferred, the Class III anti-CEA MAb or fragment thereof is
humanized, and wherein the humanized MAb retains substantially the Class
III anti-CEA binding specificity of a murine Class III anti-CEA MAb. Also
preferred, the Class III anti-CEA MAb or fragment thereof is a chimeric
MAb, and wherein the chimeric MAb retains substantially the Class III
anti-CEA binding specificity of murine Class III anti-CEA MAb. Still
preferred, the Class III anti-CEA MAb or fragment thereof is a fully
human MAb, and wherein said fully human MAb retains substantially the
Class III anti-CEA binding specificity of murine Class III anti-CEA MAb.
Other preferred anti-CEA Mabs for this purpose include Class II Mabs or
fragments thereof, that are not CD66a-d cross-reactive which are
discussed in greater detail herein. Another embodiment includes Class II
anti-CEA Mabs or fragments thereof, that may react with CD66a, b and d
but not CD66c or Class I Mabs or fragments thereof, that react with
CD66a, b, or d as well as CD66c (by definition a Class I Mab binds with
CD66c).
[0011] In one embodiment of the present invention, the Class III anti-CEA
monoclonal antibody or fragment thereof is preferably a MN-14 antibody or
fragment thereof. More preferably, the MN-14 monoclonal antibody or
fragment thereof comprises the complementarity-determining regions (CDRs)
of a murine MN-14 monoclonal antibody, wherein the CDRs of the light
chain variable region of the MN-14 antibody comprises CDR1 comprising the
amino acid sequence KASQDVGTSVA (SEQ ID NO: 20); CDR2 comprising the
amino acid sequence WTSTRHT (SEQ ID NO: 21); and CDR3 comprising the
amino acid sequence QQYSLYRS (SEQ ID NO: 22); and the CDRs of the heavy
chain variable region of the Class III anti-CEA antibody comprises CDR1
comprising TYWMS (SEQ ID NO: 23); CDR2 comprising EIHPDSSTINYAPSLKD (SEQ
ID NO: 24); and CDR3 comprising LYFGFPWFAY (SEQ ID NO: 25). Also
preferred, the MN-14 monoclonal antibody reacts with CEA and is
unreactive with normal cross-reactive antigen (NCA) and meconium antigen
(MA). Most preferably, the MN-14 monoclonal antibody or fragment thereof
is a humanized, chimerized or fully human MN-14 antibody or fragment
thereof.
[0012] In a preferred embodiment, the framework regions (FRs) of the light
and heavy chain variable regions of the humanized MN-14 antibody or
fragment thereof comprise at least one amino acid substituted from the
corresponding FRs of a murine MN-14 monoclonal antibody. Specifically,
the humanized MN-14 antibody or fragment thereof preferably comprises at
least one amino acid from the corresponding FR of the murine MN-14
antibody is selected from the group consisting of amino acid residue 24
(A), 28 (D), 30 (T), 48 (I), 49 (G), 74 (A) and 94 (S) of the murine
heavy chain variable region (KLHuVhAIGA) of FIG. 14A-C. Likewise, the
humanized MN-14 antibody or fragment thereof may also comprise at least
one amino acid from said corresponding FR of the murine MN-14 light chain
variable region. Still preferred, the humanized MN-14 antibody or
fragment thereof comprises the light chain variable region as set forth
in FIG. 13A, and the heavy chain variable region set forth in FIG. 14A-C
designated as KLHuVhAIGA.
[0013] In the first embodiment of the present invention, the therapeutic
agent is selected from the group consisting of a naked antibody, a
cytotoxic agent, a drug, a radionuclide, an immunomodulator, a
photoactive therapeutic agent, an immunoconjugate, a hormone, or a
combination thereof, optionally formulated in a pharmaceutically
acceptable vehicle. It is also contemplated herein that the therapeutic
agent is not dacarbazine (DTIC).
[0014] The second embodiment of the present invention describes a method
for treating medullary as well as non-medullary thyroid carcinoma
comprising administering to a subject, either concurrently or
sequentially, a therapeutically effective amount a Class III anti-CEA
monoclonal antibody or fragment thereof and at least one therapeutic
agent, and optionally formulated in a pharmaceutically acceptable
vehicle. Preferably, the antibody fragment is selected from the group
consisting of F(ab').sub.2, Fab', Fab, Fv and scFv. Also preferred, the
Class III anti-CEA MAb or fragment thereof is humanized, wherein said
humanized MAb retains substantially the Class III anti-CEA binding
specificity of a murine Class III anti-CEA MAb. It is also contemplated
that the Class III anti-CEA MAb or fragment thereof is a chimeric MAb,
and wherein said chimeric MAb retains substantially the Class III
anti-CEA binding specificity of murine Class III anti-CEA MAb.
[0015] In a preferred embodiment, the Class III anti-CEA monoclonal
antibody or fragment thereof is a MN-14 antibody or fragment thereof.
Preferably, the MN-14 monoclonal antibody or fragment thereof comprises
the complementarity-determining regions (CDRs) of a murine MN-14
monoclonal antibody, wherein the CDRs of the light chain variable region
of said MN-14 antibody comprises CDR1 comprising the amino acid sequence
KASQDVGTSVA (SEQ ID NO: 20); CDR2 comprising the amino acid sequence
WTSTRHT (SEQ ID NO: 21); and CDR3 comprising the amino acid sequence
QQYSLYRS (SEQ ID NO: 22); and the CDRs of the heavy chain variable region
of said Class III anti-CEA antibody comprises CDR1 comprising TYWMS (SEQ
ID NO: 23); CDR2 comprising EIHPDSSTINYAPSLKD (SEQ ID NO: 24); and CDR3
comprising LYFGFPWFAY (SEQ ID NO: 25). Also preferred, the MN-14
monoclonal antibody is humanized, chimerized or fully human, and reacts
with CEA and is unreactive with normal cross-reactive antigen (NCA) and
meconium antigen. Also preferred, the MN-14 antibody or fragment thereof
is administered in a dosage of 100 to 600 milligrams protein per dose per
injection. Most preferably, the MN-14 antibody or fragment thereof is
administered in a dosage of 300-400 milligrams protein per dose per
injection.
[0016] In the methods of the instant invention, the framework regions
(FRs) of the light and heavy chain variable regions of said humanized
MN-14 antibody or fragment thereof preferably comprise at least one amino
acid substituted from the corresponding FRs of a murine MN-14 monoclonal
antibody. More preferred, the humanized MN-14 antibody or fragment
thereof comprising at least one amino acid from said corresponding FR of
said murine MN-14 antibody is selected from the group consisting of amino
acid residue 24, 28, 30, 48, 49, 74 and 94 of the murine heavy chain
variable region of FIG. 14A-C, as noted above. Also preferred, the
humanized MN-14 antibody or fragment thereof comprising at least one
amino acid from said corresponding FR of said murine MN-14 light chain
variable region. Most preferably, the humanized MN-14 antibody or
fragment thereof comprises the light chain variable region as set forth
in FIG. 13A (middle sequence) or FIG. 22A (hMN-14) or FIG. 23A and the
heavy chain variable region set forth in FIG. 14A-C designated as
KLHuVhAIGA or FIG. 22B (hMn-14) or FIG. 23B.
[0017] The methods of the instant invention may further comprise
administering to a subject, either concurrently or sequentially, a
therapeutically effective amount of a second humanized, chimeric, human
or murine monoclonal antibody or fragment thereof selected from the group
consisting of a monoclonal antibody or fragment thereof reactive with
EGP-1, EGP-2 (e.g., 17-1A), IL-6, insulin-like growth factor-1, MUC-1,
MUC-2, MUC-3, MUC-4, PAM-4, KC4, TAG-72, EGFR, HER2/neu, BrE3, Le-Y, A3,
A33, Ep-CAM, AFP, Tn, Thomson-Friedenreich antigens, tumor necrosis
antigens, VEGF, placenta growth factor (PlGF) or other tumor angiogenesis
antigens, Ga 733, tenascin, fibronectin and a combination thereof.
Similarly, the methods may comprise administering to a subject, either
concurrently or sequentially, a therapeutically effective amount of a
second humanized, chimeric, human or murine monoclonal antibody or
fragment thereof selected from the group consisting of a Class I or Class
II or Class III anti-CEA monoclonal antibody or fragment thereof as
described above. Preferably, the second antibody or fragment thereof is
either naked or conjugated to a therapeutic agent.
[0018] In a preferred embodiment of the methods described herein, the
therapeutic agent is selected from the group consisting of a naked
antibody, cytotoxic agent, a drug, a radionuclide, an immunomodulator, a
photoactive therapeutic agent, an immunoconjugate of a CEA or non-CEA
antibody, a hormone, or a combination thereof, optionally formulated in a
pharmaceutically acceptable vehicle. It is also contemplated that the
therapeutic agent is not dacarbazine (DTIC).
[0019] Preferably, the therapeutic agent is a cytotoxic agent selected
from the group consisting of a drug or a toxin. For example, it is
contemplated that the drug possesses the pharmaceutical property selected
from the group consisting of antimitotic, alkylating, antimetabolite,
antiangiogenic, apoptotic, alkaloid, COX-2, and antibiotic agents and
combinations thereof. Preferably, the drug is selected from the group
consisting of nitrogen mustards, ethylenimine derivatives, alkyl
sulfonates, nitrosoureas, triazenes, folic acid analogs, anthracyclines,
taxanes, COX-2 inhibitors, pyrimidine analogs, purine analogs,
antimetabolites, antibiotics, enzymes, epipodophyllotoxins, platinum
coordination complexes, vinca alkaloids, substituted ureas, methyl
hydrazine derivatives, adrenocortical suppressants, antagonists,
endostatin, taxols, camptothecins, oxaliplatin, doxorubicins and their
analogs, and a combination thereof.
[0020] When the therapeutic agent is a microbial, plant or animal toxin,
the agent can be selected from the group consisting of ricin, abrin,
alpha toxin, saporin, ribonuclease (RNase), DNase I, Staphylococcal
enterotoxin-A, pokeweed antiviral protein, gelonin, diphtherin toxin,
Pseudomonas exotoxin, and Pseudomonas endotoxin.
[0021] It is also contemplated in the methods of the instant invention
that the therapeutic agent is an immunomodulator is selected from the
group consisting of a cytokine, a stem cell growth factor, a lymphotoxin,
a hematopoietic factor, a colony stimulating factor (CSF), an interferon
(IFN), a stem cell growth factor, erythropoietin, thrombopoietin and a
combination thereof. Preferably, the lymphotoxin is tumor necrosis factor
(TNF), said hematopoietic factor is an interleukin (IL), said colony
stimulating factor is granulocyte-colony stimulating factor (G-CSF) or
granulocyte macrophage-colony stimulating factor (GM-CSF)), said
interferon is interferons-.alpha., -.beta. or -.gamma., and said stem
cell growth factor is designated "S1 factor". Also preferred, the
immunomodulator comprises IL-1, IL-2, IL-3, IL-6, IL-10, IL-12, IL-18,
IL-21, interferon-.gamma., TNF-.alpha. or a combination thereof.
Administration of a cytokine prior to, simultaneous with, or subsequent
to exposure to a cytotoxic agent that results in myeloid or hematopoietic
toxicity is described in U.S. Pat. No. 5,120,525, which is incorporated
herein by reference in its entirety.
[0022] Also preferred the therapeutic agent is a photoactive therapeutic
agent that is a chromogen or dye or an alkylating agent that is
dacarbazine.
[0023] Also preferred, the therapeutic agent is a radionuclide that has an
energy between 20 and 10,000 keV. Preferably, the radionuclide is
selected from the group consisting of .sup.125I, .sup.131I, .sup.90Y,
.sup.88Y, .sup.225Ac, .sup.177Lu, .sup.188Re, .sup.186Re, and
combinations thereof.
[0024] In another embodiment, an immunomodulator, as described herein, is
administered prior to the administration of a therapeutically effective
amount of a anti-CEA monoclonal antibody or fragment thereof alone or an
immunomodulator is administered prior to the administration of a
therapeutically effective amount of a anti-CEA monoclonal antibody and at
least one therapeutic agent, wherein any of these components described
herein are optionally formulated in a pharmaceutically acceptable
vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1. Graphs comparing tumor volume after treatment with hMN-14
alone, DTIC alone or the combination of hMN-14 and DTIC. FIG. 1A shows
DTIC administered alone at 25 and 100 .mu.g/dose or with 250 .mu.g hMN-14
antibody and FIG. 1B shows DTIC administered alone at 50 and 75
.mu.g/dose or with 100 .mu.g hMN-14 antibody.
[0026] FIG. 2. Graph comparing tumor volume after radioimmunotherapy
(RAIT) with .sup.131I and .sup.90Y-MN-14.
[0027] FIG. 3. Graph comparing the therapeutic efficacy of several
chemotherapeutic drugs on tumor volume in TT bearing mice. TT bearing
mice were given doxorubicin @ 20 mg/m.sup.2; days 0, 1, and 2, (70
.mu.g/dose) (.largecircle.); DTIC @ 300 mg/m.sup.2; days 0, 1, and 2,
(1.08 mg/dose) (.quadrature.); doxorubicin and DTIC as above ( );
cyclophosphamide @ 600 mg/m.sup.2; day 0 (2.16 mg/dose) (.DELTA.);
vincristine @ 4.2 .mu.g/dose; day 0 (x); all 4 drugs (doxorubicin, DTIC,
cyclophosphamide, and vincristine) at the doses described for each above
(.box-solid.); or left untreated (.diamond-solid.). Groups consisted of
6-9 nude mice bearing established TT tumors. Mean tumor volume at time of
treatment was 0.51+/-0.33 cm.sup.3. Points: mean tumor size. Error bars:
std dev, and are shown only above the symbol for clarity.
[0028] FIG. 4. Graph comparing the therapeutic efficacy of combination
therapy of RAIT with .sup.90Y-labeled anti CEA MAb MN-14 and a 4-drug
combination initiated 24 hours after RAIT on tumor volume in mice. Tumor
bearing animals were either left untreated (.diamond-solid.); given the
4-drug regimen described in FIG. 1, administered on days 1, 2, and 3
(.box-solid.); 52.5 .mu.Ci .sup.90Y-MN-14 day on 0, followed by the
4-drug regimen administered on days 1, 2, and 3 (.tangle-solidup.); 52.5
.mu.Ci .sup.90Y-MN-14 on day 0 (.DELTA.); or 105 .mu.Ci .sup.90Y-MN-14 on
day 0 (.smallcircle.). N=5 for the untreated group, and n=9-10 in the
treatment groups. Mean tumor volume at time of treatment was 0.28+/-0.12
cm.sup.3. Points: mean tumor size. Error bars: std dev, and are shown
only above the symbol for clarity.
[0029] FIG. 5. Graph comparing the efficacy of RAIT plus DTIC and RAIT
plus doxorubicin and DTIC in TT bearing mice. TT bearing mice were either
left untreated (.diamond-solid.); given 105 .mu.Ci .sup.90Y-MN-14 on day
0 (.smallcircle.); 105 .mu.Ci .sup.90Y-MN-14 on day 0, followed by the
doxorubicin and DTIC regimen administered at 50% the full dosage on days
1, 2, and 3 (.tangle-solidup.); 105 .mu.Ci .sup.90Y-MN-14 day on 0,
followed by DTIC at 75% of the full dosage on days 1, 2, and 3 (.times.);
or the full dosage of DTIC, 300 mg/m.sup.2 on days 1, 2, and 3, (1.08
mg/dose) (.quadrature.). N=5 for the untreated group, and n=8-9 in the
treatment groups. Mean tumor volume at time of treatment was 0.39 +/-0.20
cm.sup.3. Points: mean tumor size. Error bars: std dev, and are shown
only above the symbol for clarity.
[0030] FIG. 6. Graph comparing the effectiveness of naked hMN-14 with
treatment regimens in mice bearing TT xenografts. Animals were given s.c.
injections of TT cells, and either left untreated (A) or given an i.v.
injection of 0.5 mg hMN-14 1 day (B) or 11 days (C) later. Lines in
panels A, B, and C represent tumor volumes of individual animals. Means
of respective treatment groups are shown in panel D. Error bars represent
standard error of the mean and are shown only in one direction for
clarity. .diamond-solid., untreated; .quadrature., day-1 treated;
.DELTA., day-11 treated.
[0031] FIG. 7. Graph comparing the effectiveness of humanized and murine
MN-14 antibodies in treating medullary thyroid carcinoma. Animals were
given s.c. injections of TT cells, and either left untreated or given an
i.v. injection of MAb (0.5 mg) 1 day later. Means of respective treatment
groups are shown. Error bars represent standard error of the mean and are
shown only in one direction for clarity. .diamond-solid., untreated;
.quadrature., hMN-14; .DELTA., murine MN-14; .times., hLL2.
[0032] FIG. 8. Graph comparing the effectiveness of different hMN-14 doses
in treating medullary thyroid carcinoma. Animals were given i.v.
injections of increasing doses of hMN-14 1 day after s.c. injection of TT
cells. Means of respective treatment groups are shown. .diamond-solid.,
untreated; , 0.125 mg; .smallcircle., 0.25 mg; .box-solid., 0.50 mg;
.times., 1.0 mg, .DELTA., 2.0 mg. Error bars represent standard error of
the mean and are shown only for the untreated group and the group that
received 0.50 mg hMN-14/mouse for clarity.
[0033] FIG. 9. Graph comparing the effectiveness of different treatment
times in TT bearing nude mice. Animals were given i.v. injections of 0.25
hMN-14 either 1 ( ), 3 (.tangle-solidup.), or 7 (.box-solid.) days after
s.c. injection of TT cells, or left untreated (.diamond-solid.). Means of
respective treatment groups are shown. Error bars represent standard
error of the mean and are shown only in one direction for clarity.
[0034] FIG. 10. Graph comparing treatment of TT bearing nude mice with
hMN-14 plus DTIC, DTIC alone, hMN-14 alone, and untreated mice. Animals
were given i.p. injections of hMN-14 at 100 .mu.g/dose on days 2, 3, 4,
5, 7, 8, 9, 10 and 11, 15, and 22, then every 7 days (.smallcircle.);
DTIC, 75 .mu.g/dose on days 2, 3, and 4 (.tangle-solidup.); the
combination of these hMN-14 and DTIC regimens (.DELTA.); or left
untreated (.diamond-solid.). Means of respective treatment groups are
shown; 10 animals/group.
[0035] FIG. 11. FIGS. 11A and 11B show the consensus DNA sequence of the
murine MN-14 variable region heavy chain (VH) (SEQ ID NO: 1) and the
amino acid sequence (SEQ ID NO: 2) encoded by the DNA sequence. The CDRs
are enclosed in boxes.
[0036] FIG. 12. FIGS. 12A and 12B show the consensus DNA sequence of the
murine MN-14 variable region light chain (VK) (SEQ ID NO: 3) and the
amino acid sequence (SEQ ID NO: 4) encoded by the DNA sequence. The CDRs
are enclosed in boxes.
[0037] FIG. 13. FIGS. 13A and 13B show the alignment of the murine MN-14
variable region (MN14VH is shown in SEQ ID NO: 2, MN14VK is shown in SEQ
ID NO: 4) of the with the human variable regions NEWM VH (SEQ ID NO: 5)
and REI VK (SEQ ID NO: 6) (FIG. 13A), and with the human KOL VH region
(SEQ ID NO: 7) (FIG. 13B). CDRs are boxed, and the murine VH FRs, which
are incorporated into the humanized VH, are marked with their positions
according to the numbering system of Kabat et al. SEQUENCES OF PROTEINS
OF IMMUNOLOGICAL INTEREST, U.S. Government Printing Office, Washington,
D.C., 1987. Murine residues outside the CDRs that were included in the
KLHuVH are indicated by a filled circle.
[0038] FIG. 14. FIGS. 14A-14C show a comparison of the amino acid sequence
between murine and humanized MN-14 VH framework residues (FR) (SEQ ID NOS
2, 26, 8-11, 27 and 12-15, respectively in order of appearance). Only
human FR residues different from the mouse are shown. CDRs for NEWM and
KOL are also not shown. The areas of amino acid substitutions in the
respective FRs are highlighted in bold, and the position of the
substitution indicated according to the Kabat et al. numbering system.
The 3 CDRs are boxed.
[0039] FIG. 15. FIG. 15 shows the effects of naked hMN-14 CEA MAb and DTIC
treatment in a human medullary thyroid cancer model.
[0040] FIG. 16. FIG. 16 shows the effects of naked hMN-14 CEA MAb and
CPT-11 treatment in an advanced human colon cancer model.
[0041] FIG. 17. FIG. 17 shows the effects of naked hMN-14 CEA MAb and
CPT-11 treatment in a low tumor burden human colon cancer model.
[0042] FIG. 18. FIG. 18 shows the effects of pre-treatment with naked
hMN-14 CEA MAb given 3 days prior to CPT-11 treatment in a human colon
cancer model.
[0043] FIG. 19. FIG. 19 shows a comparison of various administration
sequences of naked hMN-14 CEA Mab and CPT-11 in a human colon cancer
model.
[0044] FIG. 20. FIG. 20 shows the effects of GM-CSF pre-treatment on naked
hMN-14 CEA MAb therapy in a human colon cancer model.
[0045] FIG. 21. FIG. 21 shows a comparison of the effects of naked hMN-14
CEA MAb therapy on both low CEA expression and high (interferon-induced)
CEA expression tumor cells in a human colon cancer model.
[0046] FIG. 22. FIGS. 22A and 22B show the comparison of the human, murine
and humanized sequences of the Vk and VH regions of the human REI and KOL
antibodies, respectively with murine and humanized MN-14. The human
sequences of the REI Vk (SEQ ID NO: 6) in FIG. 22A are compared with the
murine (SEQ ID NO: 4) and humanized (SEQ ID NO: 19) MN-14 Vk sequences.
The closed circles indicate sequences retained from the human REI Vk
sequences. The CDRs are boxed. The human sequences of the KOL VH (SEQ ID
NO: 7) in FIG. 22B are compared with the murine (SEQ ID NO: 2) and
humanized (SEQ ID NO: 14) MN-14 VH sequences. The closed circles indicate
sequences retained from the human KOL VH sequences. The CDRs are boxed.
[0047] FIG. 23. FIGS. 23A and 23B show the Vk, the variable light chain,
and the VH, the variable heavy chain sequences of hMN-14, a humanized
Class III anti-CEA antibody. The CDR region sequences are shown in bold
and underlined. The amino acid residues and the nucleotides are numbered
sequentially. The light chain variable region is shown in FIG. 23A
(Nucleotide and encoded protein are disclosed as SEQ ID NOS 18 and 19,
respectively), and the heavy chain variable region is shown in FIG. 23B
(Nucleotide and encoded protein are disclosed as SEQ ID NOS 16 and 17,
respectively).
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0048] 1. Overview
[0049] The present invention provides methods of treatment in which a
naked anti-CEA antibody or fragment thereof and at least one therapeutic
agent are administered either sequentially or concurrently over a
treatment period. The method is particularly useful for treating
medullary thyroid carcinoma but is surprisingly useful for treating
non-medullary thyroid cancers, colorectal cancers, hepatocellular
carcinoma, pancreatic, breast, lung, head-and-neck, bladder, uterine and
ovarian cancers, and even cancers that do not express CEA at very high
levels. For example, treatment is contemplated in cancers that express
CEA at levels of at least 100 ng/g of tissue. The present method further
provides compositions comprising the anti-CEA antibody, which is
preferably a Class III anti-CEA antibody or antibody fragment in which
the antibody and the therapeutic agent are not conjugated or linked to
each other. As used herein, the phrase "Class III anti-CEA" antibody or
antibody fragment means an antibody or fragment that binds the CEA
antigen (or CD66e) and is unreactive with normal cross-reactive antigen
(NCA), meconium antigen (MA), granulocytes and CD66a-d (see, Primus et
al., U.S. Pat. No. 4,818,709, incorporated by reference). The naked Class
III anti-CEA antibody or fragment thereof may be a humanized, chimeric,
human or murine antibody. In a preferred embodiment, the naked Class III
anti-CEA antibody or fragment thereof is a humanized MN-14 antibody or
fragment thereof.
[0050] Also contemplated for use in the present invention are Class II
Mabs that are not CD66a-d cross-reactive. These are Mabs that are
reactive with CEA domains N-A1B1, A2B2, which do react with Meconium
Antigen, but not with NCA, and do not react with granulocytes. For
example, NP-3 and MN-6 are Class II anti-CEA antibodies useful in the
present invention. Additionally contemplated for use in the present
invention are Class II anti-CEA Mabs or fragments thereof, that may react
with CD66a, b and d but not CD66c or Class I Mabs or fragments thereof,
that react with CD66a, b, or d as well as CD66c (by definition a Class I
Mab binds with CD66c).
[0051] Surprisingly, the compositions and methods described herein are
also useful for treating non-medullary thyroid carcinoma, including
colorectal cancer, pancreatic cancer, breast cancer, lung cancers,
hepatocellular carcinoma, urinary bladder cancer, head-and-neck cancers,
and ovarian cancer. Because such forms of cancer express less CEA than
medullary thyroid cancers, it was unexpected that a naked Class III
anti-CEA antibody, in combination with a therapeutic agent, would be
useful for treating non-medullary thyroid carcinomas.
[0052] The mechanism of tumor cell killing by the naked Class III anti-CEA
antibody is not known with certainty and is likely involves several
mechanisms. It is hypothesized that the naked antibody alone or in
combination with the therapeutic agent may affect tumor growth by
blocking biological activities of their respective antigens or by
stimulating natural immunological functions, such as antibody-dependent
cell-mediated cytotoxicity (ADCC) or complement-mediated lysis.
Additionally, the naked antibody alone or in combination with the
therapeutic agent may treat and control the cancer by inhibiting cell
growth and cell cycle progression, inducing apoptosis, inhibiting
angiogenesis, inhibiting metastatic activity, and/or affecting tumor cell
adhesion. In fact, the anti-CEA antibody or fragment thereof of the
present invention may be more effective in treating metastases than
primary cancers, since the metastases may be more susceptible to
antagonists of tumor cell adhesion. The present treatment method provides
a treatment plan that may be optimized to provide the maximum anti-tumor
activity for individual patients by allowing the titration of the
antibody and one or more different therapeutic agents to provide an
effective treatment regimen.
[0053] In one aspect of the present invention, the naked Class III
anti-CEA antibody or fragment thereof and therapeutic agent may be
supplemented with at least one additional therapeutic agent, such as a
naked or conjugated humanized, murine, chimeric or human antibody, fusion
protein, or fragment thereof. For example, another class III CEA antibody
or antibody fragment that is non-blocking and does not bind granulocytes
or CD66a-d; a Class II anti-CEA antibody or antibody fragment that is
non-blocking and does not bind granulocytes or CD66a-d; a Class II
anti-CEA Mabs or fragments thereof, that may react with CD66a, b and d
but not CD66c, Class I Mabs or fragments thereof, that react with CD66a,
b, or d as well as CD66c (by definition a Class I Mab binds with CD66c)
or an antibody against a different carcinoma-associated epitope or
antigen, may be used as the therapeutic agent for combination therapy
with the preferred humanized MN-14 antibody. Such an additional antibody,
fusion protein or fragment thereof may bind CEA or another cancer or
tumor-associated antigen, as described in more detail below.
[0054] 2. Definitions
[0055] In the description that follows, a number of terms are used and the
following definitions are provided to facilitate understanding of the
present invention.
[0056] An antibody, as described herein, refers to a full-length (i.e.,
naturally occurring or formed by normal immunoglobulin gene fragment
recombinatorial processes) immunoglobulin molecule (e.g., an IgG
antibody) or an immunologically active (i.e., specifically binding)
portion of an immunoglobulin molecule, like an antibody fragment.
[0057] An antibody fragment is a portion of an antibody such as
F(ab').sub.2, F(ab).sub.2, Fab', Fab, Fv, scFv (single chain Fv) and the
like. Regardless of structure, an antibody fragment binds with the same
antigen that is recognized by the intact antibody.
[0058] The term "antibody fragment" also includes any synthetic or
genetically engineered protein that acts like an antibody by binding to a
specific antigen to form a complex. For example, antibody fragments
include isolated fragments consisting of the variable regions, such as
the "Fv" fragments consisting of the variable regions of the heavy and
light chains, recombinant single chain polypeptide molecules in which
light and heavy variable regions are connected by a peptide linker ("scFv
proteins"), and minimal recognition units consisting of the amino acid
residues that mimic the hypervariable region. The Fv fragments may be
constructed in different ways as to yield multivalent and/or
multispecific binding forms. In the former case of multivalent, they
react with more than one binding site against the CEA epitope, whereas
with multispecific forms, more than one epitope (either of CEA or even
against CEA and a different antigen) is bound.
[0059] As used herein, the term antibody component includes both an entire
antibody, a fusion protein, and fragments thereof.
[0060] A naked antibody is generally an entire antibody which is not
conjugated to a therapeutic agent. This is so because the Fc portion of
the antibody molecule provides effector or immunological functions, such
as complement fixation and ADCC (antibody dependent cell cytotoxicity),
which set mechanisms into action that may result in cell lysis. However,
the Fc portion may not be required for therapeutic function of the
antibody, but rather other mechanisms, such as apoptosis,
anti-angiogenesis, anti-metastatic activity, anti-adhesion activity, such
as inhibition of heterotypic or homotypic adhesion, and interference in
signaling pathways, may come into play and interfere with the disease
progression. Naked antibodies include both polyclonal and monoclonal
antibodies, and fragments thereof, that include murine antibodies, as
well as certain recombinant antibodies, such as chimeric, humanized or
human antibodies and fragments thereof. As defined in the present
invention, "naked" is synonymous with "unconjugated," and means not
linked or conjugated to the therapeutic agent with which it administered.
[0061] A chimeric antibody is a recombinant protein that contains the
variable domains of both the heavy and light antibody chains, including
the complementarity determining regions (CDRs) of an antibody derived
from one species, preferably a rodent antibody, while the constant
domains of the antibody molecule are derived from those of a human
antibody. For veterinary applications, the constant domains of the
chimeric antibody may be derived from that of other species, such as a
cat or dog.
[0062] A humanized antibody is a recombinant protein in which the CDRs
from an antibody from one species; e.g., a rodent antibody, is
transferred from the heavy and light variable chains of the rodent
antibody into human heavy and light variable domains. The constant
domains of the antibody molecule is derived from those of a human
antibody.
[0063] A human antibody is an antibody obtained from transgenic mice that
have been "engineered" to produce specific human antibodies in response
to antigenic challenge. In this technique, elements of the human heavy
and light chain locus are introduced into strains of mice derived from
embryonic stem cell lines that contain targeted disruptions of the
endogenous heavy chain and light chain loci. The transgenic mice can
synthesize human antibodies specific for human antigens, and the mice can
be used to produce human antibody-secreting hybridomas. Methods for
obtaining human antibodies from transgenic mice are described by Green et
al., Nature Genet. 7:13 (1994), Lonberg et al., Nature 368:856 (1994),
and Taylor et al., Int. Immun. 6:579 (1994). A fully human antibody also
can be constructed by genetic or chromosomal transfection methods, as
well as phage display technology, all of which are known in the art. See
for example, McCafferty et al., Nature 348:552-553 (1990) for the
production of human antibodies and fragments thereof in vitro, from
immunoglobulin variable domain gene repertoires from unimmunized donors.
In this technique, antibody variable domain genes are cloned in-frame
into either a major or minor coat protein gene of a filamentous
bacteriophage, and displayed as functional antibody fragments on the
surface of the phage particle. Because the filamentous particle contains
a single-stranded DNA copy of the phage genome, selections based on the
functional properties of the antibody also result in selection of the
gene encoding the antibody exhibiting those properties. In this way, the
phage mimics some of the properties of the B cell. Phage display can be
performed in a variety of formats, for their review, see e.g. Johnson and
Chiswell, Current Opinion in Structural Biology 3:5564-571 (1993).
[0064] Human antibodies may also be generated by in vitro activated B
cells. See U.S. Pat. Nos. 5,567,610 and 5,229,275, which are incorporated
in their entirety by reference.
[0065] A therapeutic agent is a molecule or atom which is administered
separately, concurrently or sequentially with an antibody component,
i.e., an antibody or antibody fragment, or a subfragment thereof, and is
useful in the treatment of a disease. Examples of therapeutic agents
include antibodies, antibody fragments, immunoconjugates, drugs,
cytotoxic agents, toxins, nucleases, hormones, immunomodulators,
chelators, boron compounds, photoactive agents or dyes, radioisotopes or
radionuclides, antisense oligonucleotides, immunoconjugates or
combinations thereof.
[0066] An immunoconjugate is an antibody component conjugated to a
therapeutic agent. Suitable therapeutic agents are described above.
[0067] As used herein, the term antibody fusion protein is a
recombinantly-produced antigen-binding molecule in which two or more of
the same or different natural antibody, single-chain antibody or antibody
fragment segments with the same or different specificities are linked. A
Class III anti-CEA fusion protein comprises at least one CEA binding
site. Preferably, the Class III anti-CEA fusion protein is a MN-14 fusion
protein.
[0068] Valency of the fusion protein indicates the total number of binding
arms or sites the fusion protein has to antigen(s) or epitope(s); i.e.,
monovalent, bivalent, trivalent or mutlivalent. The multivalency of the
antibody fusion protein means that it can take advantage of multiple
interactions in binding to an antigen, thus increasing the avidity of
binding to the antigen, or to different antigens. Specificity indicates
how many different types of antigen or epitope an antibody fusion protein
is able to bind; i.e., monospecific, bispecific, bispecific,
multispecific. Using these definitions, a natural antibody, e.g., an IgG,
is bivalent because it has two binding arms but is monospecific because
it binds to one type of antigen or epitope. A monospecific, multivalent
fusion protein has more than one binding site for the same antigen or
epitope. For example, a monospecific diabody is a fusion protein with two
binding sites reactive with the same antigen. The fusion protein may
comprise a multivalent or multispecific combination of different antibody
components or multiple copies of the same antibody component. For
example, the fusion protein of the present invention may be
multispecific, wherein one arm of the fusion protein (e.g., scFv or Fab)
is a Class III, anti-CEA mAb that targets CD66e and another arm of the
fusion protein is from another CEA crossreactive antibody that targets
CD66a-d.
[0069] A preferred bispecific fusion protein according to the invention
has an arm against a Class III CEA epitope, and a second arm against
CD66a-d epitopes (Class II) expressed on granulocytes. In these
embodiments, the CD66a-d binding portion should not be able to fix
complement or bind to Fc-receptors to effect ADCC (which would result in
release of cytokines from granulocytes). Though complement fixation and
effecting ADCC are preferred properties for the naked therapy embodiments
of the present invention, they should be avoided in the context of the
instant embodiments relating to bispecific fusion proteins. On normal
colon cells NCA-50/90 and CEA are both expressed, but they are restricted
to the apical face of the normal epithelial cell, and this face is
presented only to the colon lumen, and not accessible to injected
antibody. CEA released from these normal cells as CEA, or bound to dead
normal cells is eliminated in the feces. This polarization is lost when a
colon cancer develops, and both NCA-50/90 and CEA are then expressed on
the cancer cell membrane that is invading the underlying normal basement
membrane which anchors the normal epithelial cells. A bispecific antibody
such as hMN3/hMN14 is expected to react with both CEA and NCA-50/90 on
these invading cells. Furthermore, as NCA50/90 is present on granulocytes
this bispecific is expected to direct granulocytes to kill the invading
colon cancer cells. An even more preferred construct according to this
embodiment is a bispecific, trivalent protein with one arm reactive with
NCA50/90 and two arms reactive with only CEA. Another embodiment would be
a bispecific protein with two arms that bind to NCA50/90.
[0070] A preferred fusion protein also reactive with granulocytes would be
a diabody, having one arm against NCA-50/90 (example hMN-3), and one arm
against a Class III epitope on CEA (hMN14). These fusion proteins do not
have an Fc-domain so they will not activate cytokine release from
granulocytes. An even more preferred fusion protein would be a triabody
with one hMN-3 arm and two hMN14 arms. The construction of such diabodies
and triabodies is disclosed in U.S. application Ser. No. 60/404,919
(filed Aug. 22, 2002), 60/345,641 (filed Jan. 8, 2002), 60/328,835 (filed
Oct. 15, 2001), and 60/341,881 (filed Dec. 21, 2001).
[0071] Any kind of multispecific antibody made with mabs of the hMN14/NP-3
specificities are also preferred and can have an Fc-domain able to fix
complement/activate ADCC. For example, a hMN14-IgG1/[NP-3-scFv]2 fusion
protein could be used; the making of which is taught in U.S. application
Ser. No. 09/337,756.
[0072] Yet another preferred type of multispecific antibody according to
the present invention is an hMN-3 MAb which has an Fc-domain lacking the
ability to fix complement/effect-ADCC.
[0073] The fusion protein may additionally comprise a therapeutic agent.
For example, where at least one of the antibodies or fragments thereof,
such as the Class III, anti-CEA mAb that targets CD66e or its scFv or Fab
may be conjugated to cytokines, such as interferon or a
colony-stimulating factor, such as GM-CSF or G-CSF or an interleukin, all
of which are described herein.
[0074] An immunomodulator is a therapeutic agent as defined in the present
invention that when present, alters, suppresses or stimulates the body's
immune system. Typically, the immunomodulator useful in the present
invention stimulates immune cells to proliferate or become activated in
an immune response cascade, such as macrophages, B-cells, and/or T-cells.
An example of an immunomodulator as described herein is a cytokine, which
is a soluble small protein of approximately 5-20 kDa that are released by
one cell population (e.g., primed T-lymphocytes) on contact with specific
antigens, and which act as intercellular mediators between cells. As the
skilled artisan will understand, examples of cytokines include
lymphokines, monokines, interleukins, and several related signalling
molecules, such as tumor necrosis factor (TNF) and interferons.
Chemokines are a subset of cytokines. Certain interleukins and
interferons are examples of cytokines that stimulate T cell or other
immune cell proliferation.
Preparation of Monoclonal Antibodies, Including Chimeric, Humanized and
Human Antibodies
[0075] Monoclonal antibodies (MAbs) are a homogeneous population of
antibodies to a particular antigen and the antibody comprises only one
type of antigen binding site and binds to only one epitope on an
antigenic determinant. Rodent monoclonal antibodies to specific antigens
may be obtained by methods known to those skilled in the art. See, for
example, Kohler and Milstein, Nature 256: 495 (1975), and Coligan et al.
(eds.), CURRENT PROTOCOLS IN IMMUNOLOGY, VOL. 1, pages 2.5.1-2.6.7 (John
Wiley & Sons 1991) [hereinafter "Coligan"]. Briefly, monoclonal
antibodies can be obtained by injecting mice with a composition
comprising an antigen, verifying the presence of antibody production by
removing a serum sample, removing the spleen to obtain B-lymphocytes,
fusing the B-lymphocytes with myeloma cells to produce hybridomas,
cloning the hybridomas, selecting positive clones which produce
antibodies to the antigen, culturing the clones that produce antibodies
to the antigen, and isolating the antibodies from the hybridoma cultures.
[0076] MAbs can be isolated and purified from hybridoma cultures by a
variety of well-established techniques. Such isolation techniques include
affinity chromatography with Protein-A Sepharose, size-exclusion
chromatography, and ion-exchange chromatography. See, for example,
Coligan at pages 2.7.1-2.7.12 and pages 2.9.1-2.9.3. Also, see Baines et
al., "Purification of Immunoglobulin G (IgG)," in METHODS IN MOLECULAR
BIOLOGY, VOL. 10, pages 79-104 (The Humana Press, Inc. 1992).
[0077] Abs to peptide backbones are generated by well-known methods for Ab
production. For example, injection of an immunogen, such as
(peptide).sub.n-KLH, wherein KLH is keyhole limpet hemocyanin, and
n=1-30, in complete Freund's adjuvant, followed by two subsequent
injections of the same immunogen suspended in incomplete Freund's
adjuvant into immunocompetent animals. The animals are given a final i.v.
boost of antigen, followed by spleen cell harvesting three days later.
Harvested spleen cells are then fused with Sp2/0-Ag14 myeloma cells and
culture supernatants of the resulting clones analyzed for anti-peptide
reactivity using a direct-binding ELISA. Fine specificity of generated
Abs can be analyzed for by using peptide fragments of the original
immunogen. These fragments can be prepared readily using an automated
peptide synthesizer. For Ab production, enzyme-deficient hybridomas are
isolated to enable selection of fused cell lines. This technique also can
be used to raise antibodies to one or more of the chelates comprising the
linker, e.g., In(III)-DTPA chelates. Monoclonal mouse antibodies to an
In(III)-di-DTPA are known (U.S. Pat. No. 5,256,395 to Barbet).
[0078] Another method for producing antibodies is by production in the
milk of transgenic livestock. See, e.g., Colman, A., Biochem. Soc. Symp.,
63: 141-147, 1998; U.S. Pat. No. 5,827,690, both of which are
incorporated in their entirety by reference. Two DNA constructs are
prepared which contain, respectively, DNA segments encoding paired
immunoglobulin heavy and light chains. The DNA segments are cloned into
expression vectors that contain a promoter sequence that is
preferentially expressed in mammary epithelial cells. Examples include,
but are not limited to, promoters from rabbit, cow and sheep casein
genes, the cow .alpha.-lactoglobulin gene, the sheep .beta.-lactoglobulin
gene and the mouse whey acid protein gene. Preferably, the inserted
fragment is flanked on its 3' side by cognate genomic sequences from a
mammary-specific gene. This provides a polyadenylation site and
transcript-stabilizing sequences. The expression cassettes are coinjected
into the pronuclei of fertilized, mammalian eggs, which are then
implanted into the uterus of a recipient female and allowed to gestate.
After birth, the progeny are screened for the presence of both transgenes
by Southern analysis. In order for the antibody to be present, both heavy
and light chain genes must be expressed concurrently in the same cell.
Milk from transgenic females is analyzed for the presence and
functionality of the antibody or antibody fragment using standard
immunological methods known in the art. The antibody can be purified from
the milk using standard methods known in the art.
[0079] After the initial raising of antibodies to the immunogen, the
variable genes of the monoclonal antibodies can be cloned from the
hybridoma cells, sequenced and subsequently prepared by recombinant
techniques. General techniques for cloning murine immunoglobulin variable
domains are described, for example, by the publication of Orlandi et al.,
Proc. Nat'l Acad: Sci. USA 86: 3833 (1989), which is incorporated by
reference in its entirety. Humanization and chimerization of murine
antibodies and antibody fragments are well known to those skilled in the
art. A chimeric antibody is a recombinant protein that contains the
variable domains including the CDRs derived from one species of animal,
such as a rodent antibody, while the remainder of the antibody molecule;
i.e., the constant domains, is derived from a human antibody. The use of
antibody components derived from humanized and chimerized monoclonal
antibodies alleviates potential problems associated with the
immunogenicity of murine constant regions. Techniques for constructing
chimeric antibodies are well known to those of skill in the art. As an
example, Leung et al., Hybridoma 13:469 (1994), describe how they
produced an LL2 chimera by combining DNA sequences encoding the V.sub.k
and V.sub.H domains of LL2 monoclonal antibody, an anti-CD22 antibody,
with respective human K and IgG.sub.1 constant region domains.
[0080] A chimeric monoclonal antibody (MAb) can also be humanized by
replacing the sequences of the murine FR in the variable domains of the
chimeric MAb with one or more different human FR. Specifically, humanized
monoclonal antibodies are produced by transferring mouse complementary
determining regions from heavy and light variable chains of the mouse
immunoglobulin into a human variable domain, and then, substituting human
residues in the framework regions of the murine counterparts. As simply
transferring mouse CDRs into human FRs often results in a reduction or
even loss of antibody affinity, additional modification might be required
in order to restore the original affinity of the murine antibody. This
can be accomplished by the replacement of one or more human residues in
the FR regions with their murine counterparts to obtain an antibody that
possesses good binding affinity to its epitope. See, for example, Tempest
et al., Biotechnology 9:266 (1991) and Verhoeyen et al., Science 239:
1534 (1988).
[0081] In a preferred embodiment, some human residues in the framework
regions of the humanized anti-CEA antibody or fragments thereof are
replaced by their murine counterparts. Additionally, knowing that
chimeric anti-CEA exhibits a binding affinity comparable to that of its
murine counterpart, defective designs, if any, in the original version of
the humanized anti-CEA MAb can be identified by mixing and matching the
light and heavy chains of the chimeric anti-CEA to those of the humanized
version. Preferably, the humanized anti-CEA antibody is a humanized MN-14
antibody, and it preparation and sequences are disclosed in U.S. Pat. No.
5,874,540, which is incorporated in its entirety by reference. Although
the two human antibodies are REI and NEWM are the preferred antibodies
for preparing both humanized and chimeric MN-14 antibodies, a combination
of framework sequences from 2 or more different human antibodies can be
used for V.sub.H and V.sub.K. The production of humanized MAbs are
described, for example, by Jones et al., Nature 321: 522 (1986),
Riechmann et al., Nature 332:323 (1988), Verhoeyen et al., Science
239:1534 (1988), Carter et al., Proc. Nat'l Acad. Sci. USA 89: 4285
(1992), Sandhu, Crit. Rev. Biotech. 12: 437 (1992), and Singer et al., J.
Immun. 150: 2844 (1993), each of which is hereby incorporated by
reference. Further, the affinity of humanized, chimeric and human MAbs to
a specific epitope can be increased by mutagenesis of the CDRs, so that a
lower dose of antibody may be as effective as a higher dose of a lower
affinity MAb prior to mutagenesis. See for example, WO0029584A1.
[0082] In another embodiment, an antibody of the present invention is a
human Class III anti-CEA monoclonal antibody. The anti-CEA MAb, or
another human antibody, can be obtained from a transgenic non-human
animal. See, e.g., Mendez et al., Nature Genetics, 15: 146-156 (1997) and
U.S. Pat. No. 5,633,425, which are incorporated in their entirety by
reference. For example, a human antibody can be recovered from a
transgenic mouse possessing human immunoglobulin loci. Preferably, the
anti-CEA antibody is an MN-14 antibody. The mouse humoral immune system
is humanized by inactivating the endogenous immunoglobulin genes and
introducing human immunoglobulin loci. The human immunoglobulin loci are
exceedingly complex and comprise a large number of discrete segments
which together occupy almost 0.2% of the human genome. To ensure that
transgenic mice are capable of producing adequate repertoires of
antibodies, large portions of human heavy- and light-chain loci must be
introduced into the mouse genome. This is accomplished in a stepwise
process beginning with the formation of yeast artificial chromosomes
(YACs) containing either human heavy- or light-chain immunoglobulin loci
in germline configuration. Since each insert is approximately 1 Mb in
size, YAC construction requires homologous recombination of overlapping
fragments of the immunoglobulin loci. The two YACs, one containing the
heavy-chain loci and one containing the light-chain loci, are introduced
separately into mice via fusion of YAC-containing yeast spheroblasts with
mouse embryonic stem cells. Embryonic stem cell clones are then
microinjected into mouse blastocysts. Resulting chimeric males are
screened for their ability to transmit the YAC through their germline and
are bred with mice deficient in murine antibody production. Breeding the
two transgenic strains, one containing the human heavy-chain loci and the
other containing the human light-chain loci, creates progeny which
produce human antibodies in response to immunization.
[0083] Unrearranged human immunoglobulin genes also can be introduced into
mouse embryonic stem cells via microcell-mediated chromosome transfer
(MMCT). See, e.g., Tomizuka et al., Nature Genetics, 16: 133 (1997). In
this methodology microcells containing human chromosomes are fused with
mouse embryonic stem cells. Transferred chromosomes are stably retained,
and adult chimeras exhibit proper tissue-specific expression.
[0084] As an alternative, an antibody or antibody fragment of the present
invention may be derived from human antibody fragments isolated from a
combinatorial immunoglobulin library. See, e.g., Barbas et al., METHODS:
A Companion to Methods in Enzymology 2:119 (1991), and Winter et al.,
Ann. Rev. Immunol. 12: 433 (1994), which are incorporated by reference.
Many of the difficulties associated with generating monoclonal antibodies
by B-cell immortalization can be overcome by engineering and expressing
antibody fragments in E. coli, using phage display. To ensure the
recovery of high affinity, monoclonal antibodies a combinatorial
immunoglobulin library must contain a large repertoire size. A typical
strategy utilizes mRNA obtained from lymphocytes or spleen cells of
immunized mice to synthesize cDNA using reverse transcriptase. The heavy-
and light-chain genes are amplified separately by PCR and ligated into
phage cloning vectors. Two different libraries are produced, one
containing the heavy-chain genes and one containing the light-chain
genes. Phage DNA is isolated from each library, and the heavy-and
light-chain sequences are ligated together and packaged to form a
combinatorial library. Each phage contains a random pair of heavy- and
light-chain cDNAs and upon infection of E. coli directs the expression of
the antibody chains in infected cells. To identify an antibody that
recognizes the antigen of interest, the phage library is plated, and the
antibody molecules present in the plaques are transferred to filters. The
filters are incubated with radioactively labeled antigen and then washed
to remove excess unbound ligand. A radioactive spot on the autoradiogram
identifies a plaque that contains an antibody that binds the antigen.
Cloning and expression vectors that are useful for producing a human
immunoglobulin phage library can be obtained, for example, from
STRATAGENE Cloning Systems (La Jolla, Calif.).
[0085] In one embodiment, the antibodies of the present invention are
produced as described in Hansen et al., U.S. Pat. No. 5,874,540; Hansen
et al., Cancer, 71:3478 (1993); Primus et al., U.S. Pat. No. 4,818,709,
and Shively et al., U.S. Pat. No. 5,081,235, which have been incorporated
by reference in their entirety.
[0086] Production of Antibody Fragments
[0087] The present invention contemplates the use of fragments of a Class
III anti-CEA antibody, preferably a MN-14 antibody. The Class III
anti-CEA antibody or fragment thereof of the present invention does not
bind granulocytes or CD66a-d. Antibody fragments which recognize specific
epitopes can be generated by known techniques. For example, antibody
fragments can be prepared by proteolytic hydrolysis of an antibody or by
expression in E. coli of the DNA coding for the fragment. The antibody
fragments are antigen binding portions of an antibody, such as
F(ab').sub.2, Fab', Fab, Fv, scFv and the like, and can be obtained by
pepsin or papain digestion of whole antibodies by conventional methods.
[0088] For example, an antibody fragment can be produced by enzymatic
cleavage of antibodies with pepsin to provide a 100 Kd fragment denoted
F(ab').sub.2. This fragment can be further cleaved using a thiol reducing
agent, and optionally a blocking group for the sulfhydryl groups
resulting from cleavage of disulfide linkages, to produce 50 Kd Fab'
monovalent fragments. Alternatively, an enzymatic cleavage using papain
produces two monovalent Fab fragments and an Fc fragment directly. These
methods are described, for example, by Goldenberg, U.S. Pat. Nos.
4,036,945 and 4,331,647 and references contained therein, which patents
are incorporated herein in their entireties by reference. Also, see
Nisonoff et al., Arch Biochem. Biophys. 89: 230 (1960); Porter, Biochem.
J. 73: 119 (1959), Edelman et al., in METHODS IN ENZYMOLOGY VOL. 1, page
422 (Academic Press 1967), and Coligan at pages 2.8.1-2.8.10 and
2.10.-2.10.4.
[0089] Other methods of cleaving antibodies, such as separation of heavy
chains to form monovalent light-heavy chain fragments, further cleavage
of fragments, or other enzymatic, chemical or genetic techniques may also
be used, so long as the fragments bind to the antigen that is recognized
by the intact antibody.
[0090] For example, Fv fragments comprise an association of V.sub.H and
V.sub.L chains. This association can be noncovalent, as described in
Inbar et al., Proc. Nat'l. Acad. Sci. USA 69:2659 (1972). Alternatively,
the variable chains can be linked by an intermolecular disulfide bond or
cross-linked by chemicals such as glutaraldehyde. See, for example,
Sandhu, Crit. Rev. Biotech. 12:437 (1992).
[0091] Preferably, the Fv fragments comprise V.sub.H and V.sub.L chains
which are connected by a peptide linker. These single-chain antigen
binding proteins (sFv) are prepared by constructing a structural gene
comprising DNA sequences encoding the V.sub.H and V.sub.L domains which
are connected by an oligonucleotide. The structural gene is inserted into
an expression vector that is subsequently introduced into a host cell,
such as E. coli. The recombinant host cells synthesize a single
polypeptide chain with a linker peptide bridging the two V domains.
Methods for producing sFvs are described, for example, by Whitlow et al.,
Methods: A Companion to Methods in Enzymology, 2:97 (1991). Also see Bird
et al., Science 242:423 (1988), Ladner et al., U.S. Pat. No. 4,946,778;
Pack et al., Bio Technology 11:1271 (1993) and Sandhu, supra.
[0092] Another form of an antibody fragment is a peptide coding for a
single complementarity-determining region (CDR). A CDR is a segment of
the variable region of an antibody that is complementary in structure to
the epitope to which the antibody binds and is more variable than the
rest of the variable region. Accordingly, a CDR is sometimes referred to
as hypervariable region. A variable region comprises three CDRs. CDR
peptides can be obtained by constructing genes encoding the CDR of an
antibody of interest. Such genes are prepared, for example, by using the
polymerase chain reaction to synthesize the variable region from RNA of
antibody-producing cells. See, for example, Larrick et al., Methods: A
Companion to Methods in Enzymology 2:106 (1991); Courtenay-Luck, "Genetic
Manipulation of Monoclonal Antibodies," in MONOCLONAL ANTIBODIES:
PRODUCTION, ENGINEERING AND CLINICAL APPLICATION, Ritter et al. (eds.),
pages 166-179 (Cambridge University Press 1995); and Ward et al.,
"Genetic Manipulation and Expression of Antibodies," in MONOCLONAL
ANTIBODIES: PRINCIPLES AND APPLICATIONS, Birch et al., (eds.), pages
137-185 (Wiley-Liss, Inc. 1995).
[0093] Other methods of cleaving antibodies, such as separation of heavy
chains to form monovalent light-heavy chain fragments, further cleavage
of fragments, or other enzymatic, chemical or genetic techniques may also
be used, so long as the fragments bind to the antigen that is recognized
by the intact antibody.
[0094] Humanized, Chimeric and Human Anti-CEA Antibodies for Treatment
[0095] Described in the present invention are compositions and methods
using murine, chimeric, humanized and human Class III anti-CEA antibodies
and fragments thereof for treatment. Preferably, the Class III anti-CEA
antibody or fragment thereof is a MN-14 antibody or fragment thereof. The
antibodies of the present invention can be used to treat medullary
thyroid carcinoma (MTC), as well as non-MTC CEA-expressing carcinomas.
Exemplary non-MTC CEA expressing carcinomas include colorectal cancer,
pancreatic cancer, hepatocellular carcinoma, gastric cancer, lung cancer,
head-and neck cancers, urinary bladder cancer, uterine cancer, breast
cancer, and ovarian cancer.
[0096] Compositions
[0097] Contemplated herein is a composition comprising at least one Class
III anti-CEA monoclonal antibody (MAb) or fragment thereof and at least
one therapeutic agent, which are not conjugated to each other, and thus
are present in the composition as unconjugated forms of each of the
components. In compositions comprising more than one antibody or antibody
fragments, such as a second Class III anti-CEA antibody, the second
antibody is non-blocking (i.e., does not block binding of the first Class
III anti-CEA antibody or antibody fragment).
[0098] In one embodiment, the Class III anti-CEA monoclonal antibody or
fragment thereof is humanized, chimeric, or fully human, wherein the
humanized, chimeric, or fully human MAb retains substantially the Class
III anti-CEA binding specificity of a murine Class III anti-CEA MAb.
[0099] In a preferred embodiment, the Class III anti-CEA monoclonal
antibody or fragment thereof is a MN-14 antibody or fragment thereof.
Preferably, the MN-14 monoclonal antibody or fragment thereof comprises
the complementarity-determining regions (CDRs) of a murine MN-14
monoclonal antibody, wherein the CDRs of the light chain variable region
of said MN-14 antibody comprises CDR1 comprising the amino acid sequence
KASQDVGTSVA (SEQ ID NO: 20); CDR2 comprising the amino acid sequence
WTSTRHT (SEQ ID NO: 21); and CDR3 comprising the amino acid sequence
QQYSLYRS (SEQ ID NO: 22); and the CDRs of the heavy chain variable region
of said Class III anti-CEA antibody comprises CDR1 comprising TYWMS (SEQ
ID NO: 23); CDR2 comprising EIHPDSSTINYAPSLKD (SEQ ID NO: 24); and CDR3
comprising LYFGFPWFAY (SEQ ID NO: 25). Also preferred, the MN-14
monoclonal antibody reacts with CEA and is unreactive with normal
cross-reactive antigen (NCA) and meconium antigen (MA). However,
antibodies against these cross-reactive determinants may be used in
combination therapy with CEA-specific antibodies, such as combined with
the MN-14 monoclonal antibody.
[0100] In another embodiment of the present invention, the MN-14
monoclonal antibody or fragment thereof is a humanized or fully human
MN-14 antibody or fragment thereof. The framework regions (FRs) of the
light and heavy chain variable regions of the humanized MN-14 antibody or
fragment thereof preferably comprise at least one amino acid substituted
from the corresponding FRs of a murine MN-14 monoclonal antibody. Still
preferred, the humanized MN-14 antibody or fragment thereof comprises at
least one amino acid from the corresponding FR of the murine MN-14
antibody selected from the group consisting of amino acid residue 24, 28,
30, 48, 49, 74 and 94 of the murine heavy chain variable region
(KLHuVhAIGA) of FIG. 14A-C as noted above. The amino acid sequence of a
preferred humanized heavy chain variable region is also set forth in
Hansen et al., U.S. Pat. No. 5,874,540, which is incorporated by
reference in its entirety. Also preferred, the humanized heavy chain
variable region comprises the amino acid sequence set forth in FIGS.
14A-C, designated as KLHuVhAIG and KLHuVhAIGAY. In another embodiment,
the humanized MN-14 antibody or fragment thereof comprises at least one
amino acid from the corresponding FR of the murine MN-14 light chain
variable region. Most preferably, the humanized MN-14 antibody or
fragment thereof comprises the light chain variable region of FIG. 13A or
FIG. 22A or FIG. 23A. Another embodiment of the present invention is a
composition comprising a chimeric MN-14 monoclonal antibody or fragment
thereof and at least one therapeutic agent, which are not conjugated to
each other, and thus are present in the composition as unconjugated forms
of each of the components. Preferably, the chimeric MN-14 antibody or
fragment thereof comprises the CDRs of the murine MN14 light chain
variable region set forth in FIG. 13A or FIG. 22A or FIG. 23A and the
CDRs of the murine MN14 heavy chain variable region as set forth in FIGS.
14A-C or FIG. 22B or FIG. 23B.
[0101] Also described herein is a composition comprising a naked murine,
humanized, chimeric or human Class III anti-CEA antibody or fragment
thereof and a therapeutic agent, and a second naked or conjugated Class
III anti-CEA antibody or antibody fragment thereof, that is non-blocking,
i.e., does not block binding of the first Class III anti-CEA antibody or
fragment thereof, and formulated in a pharmaceutically acceptable
vehicle. In other words, both Class III anti-CEA antibodies or fragments
thereof are non-blocking to each other, thus, allowing both antibodies or
fragments thereof to bind to CEA (CD66e). Additionally, the Class III CEA
antibody or antibody fragment of the present invention, as well as those
for use in combination therapy, do not bind granulocytes or CD66a-d.
Other Class III antibodies suitable for combination therapy as a naked
antibody or as a component of an immunoconjugate, with the naked Class
III anti-CEA antibody of antibody fragment of the present invention
include the non-blocking antibodies or fragments thereof described in
Kuroki et al., JP J. Cancer Res., 78(4):386 (1987) and Hammarstrom
(Cancer Res. 52(8):2329 (1992)), that also do not bind granulocytes or
CD66a-d.
[0102] Additionally, other anti-CEA antibodies, such as Class II or Class
I anti-CEA antibodies, can be used in combination with the Class III
anti-CEA antibody of the present invention, in either a naked or
conjugated form. Such Class II antibodies or antibody fragments that can
be used for combination therapy are non-blocking and do not bind
granulocytes or CD66a-d but are reactive with meconium antigen (MA) and
CEA. For example, one or more chimeric or humanized Class II anti-CEA
antibody or fragment thereof, such as MN-6 or NP-3, may be combined with
a Class III anti-CEA antibody or fragment thereof of the present
invention. These two antibodies do not react with CD66a-d or with
granulocytes (Hansen et al., Cancer Jun. 1, 1993; 71(11):3478-85). A
number of publications disclose MAbs that recognize CEA and different
members of the CEA gene family, such as Thompson et al., J. Clin. Lab.
Anal. 5:344 (1991); Kuroki et al., J. Biol. Chem. 266:11810 (1991); Nagel
et al., Eur. J. Biochem. 214:27 (1993); Skubitz et al., J. Immunol.
155:5382 (1995); Skubitz et al., J. Leukoc. Biol. 60:106 (1996); and Chen
et al., Proc. Natl. Acad. Sci. USA 93:14851 (1996).
[0103] Moreover, the second antibody or antibody fragment is either
unconjugated (naked) or conjugated to at least one therapeutic agent
(immunoconjugate). Immunoconjugates can be prepared by indirectly
conjugating a therapeutic agent to an antibody component. General
techniques are described in Shih et al., Int. J. Cancer, 41:832 (1988);
Shih et al., Int. J. Cancer, 46:1101 (1990); and Shih et al., U.S. Pat.
No. 5,057,313. The general method involves reacting an antibody component
having an oxidized carbohydrate portion with a carrier polymer that has
at least one free amine function and that is loaded with a plurality of
drug, toxin, chelator, boron addends, or other therapeutic agent. This
reaction results in an initial Schiff base (imine) linkage, which can be
stabilized by reduction to a secondary amine to form the final conjugate.
Preferably, the anti-CEA antibody or fragment thereof in the composition
for treatment is a MN-14 antibody or fragment thereof. More preferred,
the MN-14 antibody or fragment thereof is humanized.
[0104] Also contemplated in the present invention is a composition
comprising a naked humanized, chimeric, murine or human Class III
anti-CEA antibody or fragment thereof and a therapeutic agent, and a
conjugated or unconjugated second antibody or antibody fragment thereof.
In one embodiment, the second antibody or fragment thereof is
unconjugated (naked) or conjugated to at least one therapeutic agent. Non
Class I, Class II or Class III anti-CEA antibodies and fragments thereof
that are suitable for combination therapy include, but are not limited
to, carcinoma-associated antibodies and fragments thereof. Examples of
carcinoma associated antibodies and antibody fragments bind EGP-1, EGP-2
(e.g., 17-1A), MUC-1, MUC-2, MUC-3, MUC-4, PAM-4, KC4, TAG-72, EGFR,
HER2/neu, BrE3, Le-Y, A3, A33, Ep-CAM, AFP, Tn, Thomson-Friedenreich
antigens, tumor necrosis antigens, VEGF, PIGF or other tumor angiogenesis
antigens, Ga 733, IL-6, insulin-like growth factor-1, tenascin,
fibronectin or a combination thereof. As discussed supra, non-blocking
Class II and Class III anti-CEA MAbs that do not bind CD66a-d or
granulocytes or alternatively, Class II anti-CEA MAbs that do bind CD66a,
b and d or Class I anti-CEA MAbs that bind CD66a, b and d, as well as
CD66c, may also be used in combination with Class III CEA antibodies.
Other antibodies and antibody fragments suitable for combination therapy
also include those targeted against oncogene markers or products, or
antibodies against tumor-vasculature markers, such as the angiogenesis
factor, Placental Growth Factor (PlGF), and antibodies against certain
immune response modulators, such as antibodies to CD40.
[0105] Methods
[0106] Also described in the present invention are methods for treating
medullary thyroid carcinoma and non-medullary thyroid carcinomas.
Non-medullary thyroid carcinomas include colorectal cancer and any other
CEA expressing tumor, such as pancreatic cancer, breast cancer,
hepatocellular carcinoma, ovarian cancer, certain kinds of lung,
head-and-neck, endometrial, bladder, and liver cancers that express
variable quantities of CEA. The CEA levels in these types of cancers are
much lower than present in medullary thyroid carcinomas but all that is
necessary is that the CEA levels be sufficiently high so that the Class
III anti-CEA therapy provides an effective treatment. Normal colon mucosa
has about 100-500 ng/gram but carcinomas expressing CEA at levels of
about 5 mcg/gram of tissue are suitable for treatment with the methods
described in the instant invention.
[0107] For example, contemplated herein is a method for treating medullary
thyroid carcinoma or non-medullary thyroid carcinoma comprising
administering to a subject, either concurrently or sequentially, a
therapeutically effective amount of a Class III anti-CEA monoclonal
antibody or fragment thereof and at least one therapeutic agent, and
optionally formulated in a pharmaceutically acceptable vehicle.
Preferably, the Class III anti-CEA monoclonal antibody or fragment
thereof is chimeric, murine, humanized or human, wherein the chimeric,
humanized, murine, or human Class III anti-CEA MAb retains substantially
the Class III anti-CEA binding specificity of the murine MAb. More
preferably, the Class III anti-CEA antibody is humanized, and most
preferably, the humanized MN-14 monoclonal antibody, as described herein
and in U.S. Pat. No. 5,874,540. Preferably the therapeutic agent is a
cytotoxic agent, more preferably an alkylating agent, and most
preferably, dacarbazine (DTIC). But in another embodiment, the
therapeutic agent may also not be DTIC. Other classes of anti-cancer
cytostatic and cytotoxic agents, such as 5-fluorouracil, CPT-11 (which is
also known as irinotecan and camptosar) and oxaliplatin can also be used
in combinations with these antibodies, especially in the therapy of
colorectal cancers. In other cancer types, cancer drugs that are known to
be effective are also good candidates for combining with the antibody
therapies proposed herein.
[0108] Also contemplated herein is a method for treating medullary thyroid
carcinoma and non-medullary thyroid carcinoma comprising administering to
a subject, either concurrently or sequentially, a therapeutically
effective amount of a first Class III anti-CEA monoclonal antibody or
fragment thereof and at least one therapeutic agent, and a naked or
conjugated second humanized, chimeric, human or murine monoclonal
antibody or fragment thereof, and optionally formulated in a
pharmaceutically acceptable vehicle. Preferably, the first Class III
anti-CEA MAb is a humanized MN-14 antibody or fragment thereof. In one
embodiment, the second antibody or fragment thereof is a
carcinoma-associated antibody or fragment thereof selected from the group
consisting of a monoclonal antibody or fragment thereof reactive with
TAG-72, EGFR, HER2/neu, MUC1, MUC2, MUC3, MUC4, EGP-1, EGP-2, AFP, Tn,
IL-6, insulin growth factor-1, or another such tumor-associated antigen,
as described above. In another embodiment, the second antibody or
fragment thereof can be a different Class III anti-CEA antibody or
fragment thereof that is non-blocking and does not bind granulocytes or
CD66a-d.
[0109] In another embodiment, the second anti-CEA antibody is a Class II
antibody or fragment thereof, such as those described in Hammarstrom and
Kuroki, provided that they do not bind granulocytes or CD66a-d. In
another embodiment, this antibody includes Class I MAbs or fragments
thereof, that react with CD66a, b, or d as well as CD66c. The antibodies
and fragments thereof may be administered either concurrently or
sequentially with each other or the therapeutic agent. In one embodiment,
the second antibody or fragment thereof is either naked or conjugated to
a therapeutic agent.
[0110] Accordingly, the present invention contemplates the administration
of naked murine, humanized, chimeric and human anti-CEA antibodies and
fragments thereof sequentially or concurrently with one or more
therapeutic agents, or administered as a multimodal therapy. A Class III,
anti-CEA antibody is preferred but any anti-CEA antibody that targets
tumor cells are useful in the present invention. A naked Class III
anti-CEA antibody as described herein can significantly increase the
chemosensitivity of cancer cells to one or more therapeutic agents. For
example, treatment of colon cancer cells with a naked Class III, anti-CEA
antibody, MN-14 as described herein, either before or concurrently with a
therapeutic agent, such as CPT-11, 5'-fluorouracil (5-FU) or oxaliplatin,
improves a cell's response to a therapeutic agent, such as a cytotoxic
drug. Further, these therapeutic methods of treatment with a naked Class
III, anti-CEA antibody alone or in combination with a therapeutic agent
can be further enhanced by administering an immunomodulator as described
herein, prior to the administration of the naked antibody or the
administration of the naked antibody and at least one of the therapeutic
agents.
[0111] Multimodal therapies of the present invention include immunotherapy
with a Class III anti-CEA antibody or fragment thereof, and a therapeutic
agent, supplemented with administration of an unconjugated or conjugated
antibody, unconjugated or conjugated fusion protein, or fragment thereof.
For example, an unconjugated humanized, chimeric, murine or human MN-14
MAb or fragment thereof may be combined with another naked humanized,
murine, chimeric or human Class III anti-CEA antibody (such as an
antibody against a different epitope on CEA and also does not bind
granulocytes or CD66a-d), or a humanized, chimeric, murine or human Class
III anti-CEA antibody immunoconjugate conjugated to a radioisotope,
chemotherapeutic agent, cytokine, enzyme, enzyme-inhibitor, hormone or
hormone antagonist, metal, toxin, antisense oligonucleotide (e.g.,
anti-bcl-2), or a combination thereof. A naked Class III anti-CEA
antibody or fragment thereof may also be combined with a conjugated or
unconjugated fusion protein of a murine, humanized, chimeric or human
Class III anti-CEA antibody. However, the Class III anti-CEA antibodies
for combination therapy are non-blocking to each other and unable to bind
granulocytes or CD66a-d. Preferably, the naked Class III anti-CEA
antibody is administered sequentially or concurrently with the second
naked or conjugated antibody, fusion protein, or fragment thereof. Also
preferred, one of the antibodies or antibody fragments for use in
combination therapy is a naked humanized MN-14 antibody or fragment
thereof. Additionally, the second antibody used as a naked or conjugated
antibody, fusion protein, or fragment thereof, may be a human, humanized,
chimeric or murine Class II CEA antibody or fragment thereof that is
non-blocking and does not bind granulocytes or CD66a-d. A preferred
combination of antibodies according to this embodiment would include a
naked cross reactive anti-CD66a-d antibody which lacks an effector
function, which does not activate complement and does not induce cytokine
release. In addition, a cross reactive anti-CD66a-d Fab' or even a
F(ab+).sub.2 would likely not damage granulocytes and could be used with
a Class III anti-CEA MAb or a Class II anti-CEA MAb of the NP-3 type.
[0112] In the methods described herein, subjects receive at least one
naked Class III anti-CEA antibody or fragment thereof, administered
before, after or in conjunction with a therapeutic agent. In one
embodiment, a Class III anti-CEA antibody is used for pretreating cells,
i.e., administered before a therapeutic agent. Preferably, the class III
anti-CEA antibody is an MN-14 antibody, such as a humanized MN-14
(hMN-14) that is administered at least one hour before a therapeutic
agent, such as 5-FU or CPT-11.
[0113] Preferably, the therapeutic agent is a drug used in standard cancer
chemotherapy, such as taxane or platinum drugs in ovarian cancer,
fluorouracil, CPT-11, and oxaloplatin drugs in colorectal cancer,
gemcitabine in pancreatic and other cancers, or taxane derivatives in
breast cancers. COX-2 inhibitors represent still another class of agents
that show activity in combination with typical cytotoxic agents in cancer
chemotherapy, and can be used in this invention in the same way, but
combined in addition with CEA antibodies alone and in combination with
other cancer-associated antibodies. Optionally, these drugs can be used
in combination with radiolabeled antibodies, either CEA antibody
conjugates or radioconjugates with other carcinoma-associated antibodies,
of the kinds described above. Also preferred, the Class III anti-CEA
antibody or fragment thereof is a MN-14 antibody or fragment thereof.
Still preferred, the MN-14 antibody or fragment thereof is humanized.
[0114] In a preferred embodiment, a naked Class III anti-CEA antibody or
fragment thereof is administered sequentially (either prior to or after)
or concurrently with dacarbazine (DTIC), doxorubin, cyclophosphamide or
vincristine, or any combination of these. For example, DTIC and
cylcophosphamide may be administered sequentially or concurrently with a
naked Class III anti-CEA antibody or fragment thereof. Preferably, the
anti-CEA antibody or fragment thereof is a humanized MN-14 antibody or
fragment thereof. Similarly, 5-fluorouracil in combination with folinic
acid, alone or in combination irinotecan (CPT-11) or in combination with
oxaliplatin, is a regimen used to treat colorectal cancer. Other suitable
combination chemotherapeutic regimens are well known, such as with
oxaliplatin alone, or in combination with these other drugs, to those of
skill in the art. Accordingly, combination therapy with any of these
chemotherapeutic agents and a naked Class III anti-CEA antibody or
fragment thereof can be used to treat MTC or non-MTC, depending on the
regimen used. In medullary thyroid carcinoma, still other
chemotherapeutic agents may be preferred, such as one of the alkylating
agents (e.g., DTIC), as well as gemcitabine and other more recent classes
of cytotoxic drugs. The chemotherapeutic drugs and a naked Class III
anti-CEA antibody or fragment thereof, can be administered in any order,
or together. In other words, the antibody and therapeutic agent may be
administered concurrently or sequentially. In a preferred multimodal
therapy, both chemotherapeutic drugs and naked Class III anti-CEA
antibodies or fragments thereof are administered before, after, or
co-administered with a conjugated or unconjugated anti-CEA antibody,
fusion protein, or fragment thereof, according to the present invention.
Preferably, the Class III anti-CEA antibody or fragment thereof is a
humanized MN-14 antibody or fragment thereof.
[0115] A preferred treatment schedule of multimodal treatment is
administering both hMN-14 and DTIC for 3 days, and administering only
hMN-14 on days 7, 14, 21 and then every 21 days for a treatment duration
of 12 months. The doses of hMN-14 are 0.5-15 mg/kg body weight per
infusion, more preferably 2-8, and still more preferably 3-5 mg/kg per
infusion, and the doses of DTIC are as currently applied at the preferred
dose clinically, but could also be given at two-thirds or less of the
maximum preferred dose in use, thereby decreasing drug-related adverse
events. Repeated drug cycles can be given, such as every 1-6 months, with
continuation of the naked antibody therapy, or with different schedules
of radiolabeled antibody, drug-conjugated antibody, and inclusion of
certain cytokines, such as G-CSF and/or GM-CSF, each dose adjusted so
that toxicity to the patient is not enhanced by the therapeutic
combination. The application of a cytokine growth factor, such as G-CSF,
may enable even higher doses of myelosuppressive agents, such as
radiolabeled antibody or cytotoxic drugs, to be administered, and these
schedules and doses will be adjusted for the patients individually,
depending on their disease status and prior therapy, all influence bone
marrow status and tolerability to additional cytotoxic therapies. In a
preferred embodiment, the MN-14 antibody or fragment thereof is
administered in a dosage of 100-600 milligrams protein per dose per
injection. Still preferred, the MN-14 antibody or fragment thereof is
administered in a dosage of 300-400 milligrams of protein per dose per
injection, with repeated doses preferred. The preferred antibody schedule
is infusing once weekly or even less frequently, such as once every other
week or even every third week, depending on a number of factors,
including the extent of the disease and the amount of CEA circulating in
the patient's blood.
[0116] Therapeutic Agents
[0117] The therapeutic agents recited here are those agents that also are
useful for administration separately with a naked antibody, as described
herein. Suitable therapeutic agents can be selected from the group
consisting of a cytotoxic agent, a toxin, a hormone, a radionuclide, an
immunomodulator, a photoactive therapeutic agent (such as a chromagen or
dye), an antisense oligonucleotide, an immunoconjugate, another naked
antibody, a hormone, or a combination thereof. Therapeutic agents
include, for example, chemotherapeutic drugs such as vinca alkaloids and
other alkaloids, anthracyclines, epidophyllotoxins, taxanes,
antimetabolites, alkylating agents, antibiotics, COX-2 inhibitors,
antimitotics, antiangiogenic and apoptotoic agents, particularly
doxorubicin, methotrexate, taxol, CPT-11, camptothecans, and others from
these and other classes of anticancer agents, and the like. Other useful
cancer chemotherapeutic drugs for the preparation of immunoconjugates and
antibody fusion proteins include nitrogen mustards, alkyl sulfonates,
nitrosoureas, triazenes, oxaliplatin, folic acid analogs, COX-2
inhibitors, pyrimidine analogs, purine analogs, platinum coordination
complexes, hormones, toxins (e.g., RNAse, Psudomonas exotoxin), and the
like. Preferred therapeutic agents include DTIC, CPT-11, 5-fluorouracil,
taxol, oxaliplatin, doxorubicin, cyclophosphamide and vincristine, or a
combination thereof, depending on the malignancy to be treated. Suitable
chemotherapeutic agents are described in REMINGTON'S PHARMACEUTICAL
SCIENCES, 19th Ed. (Mack Publishing Co. 1995), and in GOODMAN AND
GILMAN'S THE PHARMACOLOGICAL BASIS OF THERAPEUTICS, 7th Ed. (MacMillan
Publishing Co. 1985), as well as revised editions of these publications.
Other suitable chemotherapeutic agents, such as experimental drugs, are
known to those of skill in the art.
[0118] A toxin, such as Pseudomonas exotoxin, may also be administered
with a naked Class III anti-CEA antibody or fragment thereof. Preferably,
the Class III anti-CEA antibody or fragment thereof is a humanized MN-14
antibody or fragment thereof. Other suitable microbial, plant or animal
toxins to be administered unconjugated to, but before, after, or
simultaneously with the naked Class III anti-CEA antibody or fragment
thereof include ricin, abrin, ribonuclease (RNase), DNase I,
Staphylococcal enterotoxin-A, pokeweed antiviral protein, gelonin,
diphtherin toxin, Pseudomonas exotoxin, and Pseudomonas endotoxin. See,
for example, Pastan et al., Cell 47:641 (1986), and Goldenberg, CA-A
Cancer Journal for Clinicians 44:43 (1994). Additional toxins suitable
for use in the present invention are known to those of skill in the art
and are disclosed in U.S. Pat. No. 6,077,499, which is incorporated in
its entirety by reference. These can be derived, for example, from
animal, plant and microbial sources, or chemically or recombinantly
engineered. The toxin can be a plant, microbial, or animal toxin, or a
synthetic variation thereof.
[0119] An immunomodulator, such as a cytokine may also be administered
unconjugated to the chimeric, murine, humanized or human Class III
anti-CEA antibody or fragment thereof of the present invention. As used
herein, the term "immunomodulator" includes cytokines, stem cell growth
factors, lymphotoxins, such as tumor necrosis factor (TNF), and
hematopoietic factors, such as interleukins (e.g., interleukin-1 (IL-1),
IL-2, IL-3, IL-6, IL-10, IL-12, IL-18, and IL-21), colony stimulating
factors (e.g., granulocyte-colony stimulating factor (G-CSF) and
granulocyte macrophage-colony stimulating factor (GM-CSF)), interferons
(e.g., interferons-.alpha., -.beta. and -.gamma.), the stem cell growth
factor designated "Si factor," erythropoietin and thrombopoietin.
Examples of suitable immunomodulator moieties include IL-2, IL-6, IL-10,
IL-12, IL-18, interferon-.gamma., TNF-.alpha., and the like. Therefore,
subjects can receive a naked Class III anti-CEA antibody or fragment
thereof and a separately administered cytokine, which can be administered
before, concurrently or after administration of the naked Class III
anti-CEA antibody or fragment thereof. Since some antigens may also be
immunomodulators, CD40 antigen, for example, may also be administered in
combination with a naked Class III anti-CEA antibody or fragment thereof
either together, before or after the naked antibody or antibody
combinations are administered. Additionally, radionuclides suitable for
treating a diseased tissue include, but are not limited to, .sup.32P,
.sup.33P, .sup.47Sc, .sup.59Fe, .sup.64Cu, .sup.67Cu, .sup.75Se,
.sup.77As, .sup.89Sr, .sup.90Y, .sup.99Mo, .sup.105Rh, .sup.109Pd,
.sup.111Ag, .sup.125I, .sup.131I, .sup.142Pr, .sup.143Pr, .sup.149Pm,
.sup.153Sm, .sup.161Tb, .sup.166Ho, .sup.169Er, .sup.177Lu, .sup.186Re,
.sup.188Re, .sup.189Re, .sup.194Ir, .sup.198Au, .sup.199Au, .sup.211Pb,
.sup.212Pb, and .sup.213Bi, .sup.58Co, .sup.67Ga, .sup.80mBr, .sup.99mTc,
.sup.103mRh, .sup.109Pt, .sup.111In, .sup.119Sb, .sup.161Ho, .sup.189mOs,
.sup.192Ir, .sup.152Dy, .sup.211At, .sup.212Bi, .sup.223Ra, .sup.219Rn,
.sup.215Po, .sup.211Bi, .sup.225Ac, .sup.221Fr, .sup.217At, .sup.213Bi,
.sup.88Y and .sup.255Fm. Preferred radionuclides are .sup.125I,
.sup.131I, .sup.90Y, .sup.177Lu, and .sup.225Ac. Also preferred, the
radionuclide has an energy between 20 and 10,000 keV.
[0120] Pharmaceutically Acceptable Vehicles
[0121] The naked murine, humanized, chimeric and human Class III anti-CEA
MAbs to be delivered to a subject can comprise one or more
pharmaceutically acceptable vehicles, one or more additional ingredients,
or some combination of these.
[0122] The unconjugated Class III anti-CEA antibodies and fragments
thereof of the present invention can be formulated according to known
methods to prepare pharmaceutically useful compositions. Preferably, the
Class III anti-CEA antibody or fragment thereof is a MN-14 antibody or
fragment thereof. Sterile phosphate-buffered saline is one example of a
pharmaceutically acceptable vehicle. Other acceptable vehicles are
well-known to those in the art. See, for example, Ansel et al.,
PHARMACEUTICAL DOSAGE FORMS AND DRUG DELIVERY SYSTEMS, 5th Edition (Lea &
Febiger 1990), and Gennaro (ed.), REMINGTON'S PHARMACEUTICAL SCIENCES,
18th Edition (Mack Publishing Company 1990), and revised editions
thereof.
[0123] The unconjugated Class III anti-CEA antibody or fragment thereof of
the present invention can be formulated for intravenous administration
via, for example, bolus injection or continuous infusion. Preferably, the
Class III anti-CEA antibody or fragments is a MN-14 antibody or fragment
thereof. Formulations for injection can be presented in unit dosage form,
e.g., in ampules or in multi-dose containers, with an added preservative.
The compositions can take such forms as suspensions, solutions or
emulsions in oily or aqueous vehicles, and can contain formulatory agents
such as suspending, stabilizing and/or dispersing agents. Alternatively,
the active ingredient can be in powder form for constitution with a
suitable vehicle, e.g., sterile pyrogen-free water, before use.
[0124] Additional pharmaceutical methods may be employed to control the
duration of action of the agent and naked antibody or fragment thereof.
Control release preparations can be prepared through the use of polymers
to complex or adsorb the naked antibody. For example, biocompatible
polymers include matrices of polyethylene-co-vinyl acetate) and matrices
of a polyanhydride copolymer of a stearic acid dimer and sebacic acid.
Sherwood et al., Bio/Technology 10:1446 (1992). The rate of release of an
antibody or fragment thereof from such a matrix depends upon the
molecular weight of the immunoconjugate or antibody, the amount of
antibody within the matrix, and the size of dispersed particles. Saltzman
et al., Biophys. J. 55: 163 (1989); Sherwood et al., supra. Other solid
dosage forms are described in Ansel et al., PHARMACEUTICAL DOSAGE FORMS
AND DRUG DELIVERY SYSTEMS, 5th Edition (Lea & Febiger 1990), and Gennaro
(ed.), REMINGTON'S PHARMACEUTICAL SCIENCES, 18th Edition (Mack Publishing
Company 1990), and revised editions thereof.
[0125] The unconjugated Class III anti-CEA antibody or fragment thereof
may also be administered to a mammal subcutaneously or even by other
parenteral routes. Moreover, the administration may be by continuous
infusion or by single or multiple boluses. In general, the dosage of an
administered naked antibody or fragment thereof for humans will vary
depending upon such factors as the patient's age, weight, height, sex,
general medical condition and previous medical history. Typically, it is
desirable to provide the recipient with a dosage of naked antibody or
fragment thereof that is in the range of from about 0.5 mg/kg to 20 mg/kg
as a single intravenous infusion, although a lower or higher dosage also
may be administered as circumstances dictate. This dosage may be repeated
as needed, for example, once per month for 4-10 months, preferably once
per every other week for 16 weeks, and more preferably, once per week for
8 weeks. It may also be given less frequently, such as every other week
for several months or given more frequently and/or over a longer
duration. The dosage may be given through various parenteral routes, with
appropriate adjustment of the dose and schedule.
[0126] For purposes of therapy, the Class III anti-CEA antibody or
fragment thereof is administered to a mammal in a therapeutically
effective amount to reduce the size of the tumor as compared to untreated
controls. Preferably, the Class III anti-CEA antibody or fragment thereof
is a humanized MN-14 antibody or fragment thereof. A suitable subject for
the present invention is usually a human, although a non-human mammal or
animal subject is also contemplated. An antibody preparation is said to
be administered in a "therapeutically effective amount" if the amount
administered is physiologically significant. An agent is physiologically
significant if its presence results in a detectable change in the
physiology of a recipient mammal. In particular, an antibody preparation
of the present invention is physiologically significant if its presence
invokes an antitumor response. A physiologically significant effect could
also be the evocation of a humoral and/or cellular immune response in the
recipient mammal.
[0127] The present invention further includes the following numbered
embodiments:
[0128] A composition comprising at least one anti-CEA monoclonal antibody
(MAb) or fragment thereof and at least one therapeutic agent. The
composition of embodiment 1, wherein said anti-CEA MAb is a Class I,
Class II or Class III anti-CEA MAb, and when said MAb is a Class I or
Class II MAb and is reactive with granulocytes, said MAb is a monovalent
form of the MAb.
[0129] 2. The composition of embodiment 1, wherein said anti-CEA MAb or
fragment thereof is humanized, wherein said humanized MAb retains
substantially the anti-CEA binding specificity of a murine anti-CEA MAb.
[0130] 3. The composition of embodiment 1, wherein said anti-CEA MAb or
fragment thereof is a chimeric MAb, and wherein said chimeric MAb retains
substantially the anti-CEA binding specificity of murine anti-CEA MAb.
[0131] 4. The composition of embodiment 1, wherein said anti-CEA MAb or
fragment thereof is a fully human MAb, and wherein said fully human MAb
retains substantially the anti-CEA binding specificity of murine anti-CEA
MAb.
[0132] 5. The composition of embodiment 1, wherein said anti-CEA
monoclonal antibody or fragment thereof is a MN-14 antibody or fragment
thereof.
[0133] 6. The composition of embodiment 5, wherein said MN-14 monoclonal
antibody or fragment thereof comprises the complementarity-determining
regions (CDRs) of a murine MN-14 monoclonal antibody, wherein the CDRs of
the light chain variable region of said MN-14 antibody comprises CDR1
comprising the amino acid sequence KASQDVGTSVA (SEQ ID NO: 20); CDR2
comprising the amino acid sequence WTSTRHT (SEQ ID NO: 21); and CDR3
comprising the amino acid sequence QQYSLYRS (SEQ ID NO: 22); and the CDRs
of the heavy chain variable region of said anti-CEA antibody comprises
CDR1 comprising TYWMS (SEQ ID NO: 23); CDR2 comprising EIHPDSSTINYAPSLKD
(SEQ ID NO: 24); and CDR3 comprising LYFGFPWFAY (SEQ ID NO: 25).
[0134] 7. The composition of embodiment 1, wherein said anti-CEA
monoclonal antibody reacts with CEA and is unreactive with normal
cross-reactive antigen (NCA) and meconium antigen (MA).
[0135] 8. The composition of embodiment 7, wherein said MN-14 monoclonal
antibody or fragment thereof is a humanized MN-14 antibody or fragment
thereof.
[0136] 9. The composition of embodiment 7, wherein said MN-14 monoclonal
antibody or fragment thereof is a chimeric MN-14 antibody or fragment
thereof.
[0137] 10. The composition of embodiment 7, wherein said MN-14 monoclonal
antibody or fragment thereof is a fully human MN-14 antibody or fragment
thereof.
[0138] 11. The composition of embodiment 8, wherein the framework regions
(FRs) of the light and heavy chain variable regions of said humanized
MN-14 antibody or fragment thereof comprise at least one amino acid
substituted from the corresponding 1-Rs of a murine MN-14 monoclonal
antibody.
[0139] 12. The composition of embodiment 11, wherein said humanized MN-14
antibody or fragment thereof comprises at least one amino acid from said
corresponding FR of said murine MN-14 antibody is selected from the group
consisting of amino acid residue 24, 28, 30, 48, 49, 74 and 94 of the
murine heavy chain variable region (KLHuVhAIGA) of FIG. 14A-C or FIG. 22B
(hMn-14) or FIG. 23B.
[0140] 13. The composition of embodiment 11, wherein said humanized MN-14
antibody or fragment thereof comprises at least one amino acid from said
corresponding FR of said murine MN-14 light chain variable region.
[0141] 14. The composition of embodiment 8, wherein said humanized MN-14
antibody or fragment thereof comprises the light chain variable region as
set forth in FIG. 13A or FIG. 22A or FIG. 23A, and the heavy chain
variable region set forth in FIG. 14A-C designated as KLHuVhAIGA or FIG.
22B (hMN-14) or FIG. 23B.
[0142] 15. The composition of embodiment 9, wherein said chimeric MN-14
antibody or fragment thereof comprises the light chain variable region as
set forth in FIG. 13A designated as murine MN-14 VK and the heavy chain
variable region set forth in FIG. 14A-C designated as murine MN-14 VH.
[0143] 16. The composition of any of embodiments 1-15, wherein said
fragment is selected from the group consisting of F(ab').sub.2, Fab',
Fab, Fv and scFv.
[0144] 17. The composition of any of embodiments 1-15, wherein said
therapeutic agent is selected from the group consisting of a naked
antibody, a cytotoxic agent, a drug, a radionuclide, an immunomodulator,
a photoactive therapeutic agent, an immunoconjugate, a hormone, a toxin,
an antisense oligonucleotide, or a combination thereof, optionally
formulated in a pharmaceutically acceptable vehicle.
[0145] 18. The composition of embodiment 17, wherein said combination
thereof comprises vincristine, doxorubicin, oxaliplatin, CPT-11,
fluorouracil, DTIC and cyclophosphamide.
[0146] 19. The composition of embodiment 17, wherein said therapeutic
agent is a naked antibody or an immunoconjugate.
[0147] 20. The composition of embodiment 19, wherein said naked antibody
or an antibody portion of said immunoconjugate comprises a humanized,
chimeric, human or murine monoclonal antibody or fragment thereof
selected from the group consisting of a monoclonal antibody or fragment
thereof reactive with EGP-1, EGP-2 (e.g., 17-1A), MUC-1, MUC-2, MUC-3,
MUC-4, PAM-4, KC4, TAG-72, EGFR, HER2/neu, BrE3, Le-Y, A3, A33, Ep-CAM,
AFP, Tn, Thomson-Friedenreich antigens, tumor necrosis antigens, VEGF,
PlGF, or other tumor angiogenesis antigens, Ga 733, IL-6, insulin-like
growth factor-1, tenascin, fibronectin or a combination thereof.
[0148] 21. The composition of embodiment 20, wherein said fragment is
selected from the group consisting of F(ab).sub.2, F(ab').sub.2, Fab',
Fab, Fv and scFv.
[0149] 22. The composition of any of embodiments 1-15, wherein said
therapeutic agent is not DTIC.
[0150] 23. A method for treating non-medullary thyroid carcinoma
comprising administering to a subject, either concurrently or
sequentially, a therapeutically effective amount of an anti-CEA antibody
or fragment thereof and at least one therapeutic agent, and optionally
formulated in a pharmaceutically acceptable vehicle.
[0151] 24. The method of embodiment 23, wherein said anti-CEA MAb or
fragment thereof is humanized, wherein said humanized MAb retains
substantially the anti-CEA binding specificity of a murine anti-CEA MAb.
[0152] 25. The method of embodiment 23, wherein said anti-CEA MAb or
fragment thereof is a chimeric MAb, and wherein said chimeric MAb retains
substantially the anti-CEA binding specificity of murine anti-CEA MAb.
[0153] 26. The method of embodiment 23, wherein said anti-CEA monoclonal
antibody or fragment thereof is a MN-14 antibody or fragment thereof.
[0154] 27. The method of embodiment 23, wherein said MN-14 monoclonal
antibody or fragment thereof comprises the complementarity-determining
regions (CDRs) of a murine MN-14 monoclonal antibody, wherein the CDRs of
the light chain variable region of said MN-14 antibody comprises CDR1
comprising the amino acid sequence KASQDVGTSVA (SEQ ID NO: 20); CDR2
comprising the amino acid sequence WTSTRHT (SEQ ID NO: 21); and CDR3
comprising the amino acid sequence QQYSLYRS (SEQ ID NO: 22); and the CDRs
of the heavy chain variable region of said anti-CEA antibody comprises
CDR1 comprising TYWMS (SEQ ID NO: 23); CDR2 comprising EIHPDSSTINYAPSLKD
(SEQ ID NO: 24); and CDR3 comprising LYFGFPWFAY (SEQ ID NO: 25).
[0155] 28. The method of embodiment 27, wherein said MN-14 monoclonal
antibody reacts with CEA and is unreactive with normal cross-reactive
antigen (NCA) and meconium antigen (MA).
[0156] 29. The method of embodiments 28, wherein said MN-14 monoclonal
antibody or fragment thereof is a humanized MN-14 antibody or fragment
thereof.
[0157] 30. The method of embodiments 28, wherein said MN-14 monoclonal
antibody or fragment thereof is a chimeric MN-14 antibody or fragment
thereof.
[0158] 31. The method of embodiments 28, wherein said MN-14 monoclonal
antibody or fragment thereof is a fully human MN-14 antibody or fragment
thereof.
[0159] 32. The method of embodiment 29, wherein the framework regions
(FRs) of the light and heavy chain variable regions of said humanized
MN-14 antibody or fragment thereof comprise at least one amino acid
substituted from the corresponding FRs of a murine MN-14 monoclonal
antibody.
[0160] 33. The method of embodiment 32, wherein said humanized MN-14
antibody or fragment thereof comprising at least one amino acid from said
corresponding FR of said murine MN-14 antibody is selected from the group
consisting of amino acid residue 24, 28, 30, 48, 49, 74 and 94 of the
murine heavy chain variable region of FIG. 14A-C designated as KLHuVhAIGA
or FIG. 22B (hMN-14) or FIG. 23B.
[0161] 34. The method of embodiment 32, wherein said humanized MN-14
antibody or fragment thereof comprising at least one amino acid from said
corresponding FR of said murine MN-14 light chain variable region.
[0162] 35. The method of embodiment 32, wherein said humanized MN-14
antibody or fragment thereof comprises the light chain variable region as
set forth in FIG. 13A or FIG. 22A (hMN-14) or FIG. 23A and the heavy
chain variable region set forth in FIG. 14A-C designated as KLHuVhAIGA or
FIG. 22B (hMN-14) or FIG. 23B.
[0163] 36. The method of any of embodiments 23-35, wherein said fragment
is selected from the group consisting of F(ab).sub.2, F(ab').sub.2, Fab',
Fab, Fv and sFv.
[0164] 37. The method of any of embodiments 23-35, wherein said
therapeutic agent is selected from the group consisting of humanized,
chimeric, human or murine monoclonal antibody or fragment thereof
selected from the group consisting of a Class I anti-CEA monoclonal
antibody, Class II anti-CEA monoclonal antibody, Class III anti-CEA
monoclonal antibody, and a fragment thereof, and is administered either
concurrently or sequentially in a therapeutically effective amount.
[0165] 38. The method of embodiment 37, wherein said antibody or fragment
thereof is either naked or conjugated to another therapeutic agent.
[0166] 39. The method of any of embodiments 23-35, wherein said
therapeutic agent is selected from the group consisting of a naked
antibody, cytotoxic agent, a drug, a radionuclide, an immunomodulator, a
photoactive therapeutic agent, an antisense oligonucleotide, an
immunoconjugate of a CEA or non-CEA antibody, a hormone, or a combination
thereof, optionally formulated in a pharmaceutically acceptable vehicle.
[0167] 40. The method of embodiment 39, wherein said therapeutic agent is
selected from the group consisting of a humanized, chimeric, human or
murine monoclonal antibody or fragment thereof reactive with EGP-1, EGP-2
(e.g., 17-1A), IL-6, MUC-1, MUC-2, MUC-3, MUC-4, PAM-4, KC4, TAG-72,
EGFR, EGP-2, HER2/neu, BrE3, Le-Y, A3, A33, Ep-CAM, AFP, Tn,
Thomson-Friedenreich antigens, tumor necrosis antigens, VEGF, PIGF or
other tumor angiogenesis antigens, Ga 733, IL-6, insulin-like growth
factor-1, and a combination thereof, and is administered to said subject
either concurrently or sequentially in a therapeutically effective
amount.
[0168] 41. The method of embodiment 40, wherein said antibody or fragment
thereof is either naked or conjugated to another therapeutic agent.
[0169] 42. The method of any of embodiments 23-35, wherein said
therapeutic agent is not DTIC.
[0170] 43. The method of embodiment 39, wherein said cytotoxic agent is a
drug or a toxin.
[0171] 44. The method of embodiment 43, wherein said drug possesses the
pharmaceutical property selected from the group consisting of
antimitotic, alkylating, antimetabolite, antiangiogenic, apoptotic,
alkaloid, COX-2, and antibiotic agents and combinations thereof.
[0172] 45. The method of embodiment 43, wherein said drug is selected from
the group consisting of nitrogen mustards, ethylenimine derivatives,
alkyl sulfonates, nitrosoureas, triazenes, folic acid analogs,
anthracyclines, taxanes, COX-2 inhibitors, pyrimidine analogs, purine
analogs, antimetabolites, antibiotics, enzymes, epipodophyllotoxins,
platinum coordination complexes, vinca alkaloids, substituted ureas,
methyl hydrazine derivatives, adrenocortical suppressants, antagonists,
endostatin, taxols, camptothecins, doxorubicins and their analogs, and a
combination thereof.
[0173] 46. The method of embodiment 43, wherein said toxin is a microbial,
plant or animal toxin selected from the group consisting of ricin, abrin,
alpha toxin, saporin, ribonuclease (RNase), DNase I, Staphylococcal
enterotoxin-A, pokeweed antiviral protein, gelonin, diphtheria toxin,
Pseudomonas exotoxin, and Pseudomonas endotoxin.
[0174] 47. The method of embodiment 39, wherein said immunomodulator is
selected from the group consisting of a cytokine, a stem cell growth
factor, a lymphotoxin, a hematopoietic factor, a colony stimulating
factor (CSF), an interferon (IFN), a stem cell growth factor,
erythropoietin, thrombopoietin and a combination thereof.
[0175] 48. The method of embodiment 47, wherein said lymphotoxin is tumor
necrosis factor (TNF), said hematopoietic factor is an interleukin (IL),
said colony stimulating factor is granulocyte-colony stimulating factor
(G-CSF) or granulocyte macrophage-colony stimulating factor (GM-CSF)),
said interferon is interferons-.alpha., -.beta. or -.gamma., and said
stem cell growth factor is designated "S1 factor".
[0176] 49. The method of embodiment 47, wherein said immunomodulator
comprises IL-1, IL-2, IL-3, IL-6, IL-10, IL-12, IL-18, IL-21,
interferon-.gamma., TNF-.alpha. or a combination thereof.
[0177] 50. The method of embodiment 39, wherein said radionuclide has an
energy between 20 and 10,000 keV.
[0178] 51. The method of embodiment 50, wherein said radionuclide is
selected from the group consisting of .sup.125I, .sup.131I, .sup.90Y,
.sup.88Y, .sup.225Ac, .sup.177Lu, .sup.188Re, .sup.186R, and combinations
thereof.
[0179] 52. The method of embodiment 39, wherein said photoactive
therapeutic agent is a chromogen or dye.
[0180] 53. The method of embodiment 44, wherein said alkylating agent is
dacarbazine.
[0181] 54. The method of embodiment 53, wherein said MN-14 antibody or
fragment thereof is administered in a dosage of 100 to 600 milligrams
protein per dose per injection.
[0182] 55. The method of embodiment 54, wherein said MN-14 antibody or
fragment thereof is administered in a dosage of 300-400 milligrams
protein per dose per injection.
[0183] 56. A method for treating medullary thyroid carcinoma comprising
administering to a subject, either concurrently or sequentially, a
therapeutically effective amount of an anti-CEA monoclonal antibody or
fragment thereof and at least one therapeutic agent, and optionally
formulated in a pharmaceutically acceptable vehicle.
[0184] 57. The method of embodiment 56, wherein said anti-CEA MAb or
fragment thereof is humanized, wherein said humanized MAb retains
substantially the anti-CEA binding specificity of a murine anti-CEA MAb.
[0185] 58. The method of embodiment 56, wherein said anti-CEA MAb or
fragment thereof is a chimeric MAb, and wherein said chimeric MAb retains
substantially the anti-CEA binding specificity of murine anti-CEA MAb.
[0186] 59. The method of embodiment 56, wherein said anti-CEA monoclonal
antibody or fragment thereof is a MN-14 antibody or fragment thereof.
[0187] 60. The method of embodiment 59, wherein said MN-14 monoclonal
antibody or fragment thereof comprises the complementarity-determining
regions (CDRs) of a murine MN-14 monoclonal antibody, wherein the CDRs of
the light chain variable region of said MN-14 antibody comprises CDR1
comprising the amino acid sequence KASQDVGTSVA (SEQ ID NO: 20); CDR2
comprising the amino acid sequence WTSTRHT (SEQ ID NO: 21); and CDR3
comprising the amino acid sequence QQYSLYRS (SEQ ID NO: 22); and the CDRs
of the heavy chain variable region of said Class III anti-CEA antibody
comprises CDR1 comprising TYWMS (SEQ ID NO: 23); CDR2 comprising
EIHPDSSTINYAPSLKD (SEQ ID NO: 24); and CDR3 comprising LYFGFPWFAY (SEQ ID
NO: 25).
[0188] 61. The method of embodiment 60, wherein said MN-14 monoclonal
antibody reacts with CEA and is unreactive with normal cross-reactive
antigen (NCA) and meconium antigen (MA).
[0189] 62. The method of embodiments 61, wherein said MN-14 monoclonal
antibody or fragment thereof is a humanized MN-14 antibody or fragment
thereof.
[0190] 63. The method of embodiments 61, wherein said MN-14 monoclonal
antibody or fragment thereof is a chimeric MN-14 antibody or fragment
thereof.
[0191] 64. The method of embodiments 61, wherein said MN-14 monoclonal
antibody or fragment thereof is a fully human MN-14 antibody or fragment
thereof.
[0192] 65. The method of embodiment 62, wherein the framework regions
(Hes) of the light and heavy chain variable regions of said humanized
MN-14 antibody or fragment thereof comprise at least one amino acid
substituted from the corresponding FRs of a murine MN-14 monoclonal
antibody.
[0193] 66. The method of embodiment 65, wherein said humanized MN-14
antibody or fragment thereof comprising at least one amino acid from said
corresponding FR of said murine MN-14 antibody is selected from the group
consisting of amino acid residue 24, 28, 30, 48, 49, 74 and 94 of the
murine heavy chain variable region of FIG. 14A-C or 22B.
[0194] 67. The method of embodiment 65, wherein said humanized MN-14
antibody or fragment thereof comprising at least one amino acid from said
corresponding FR of said murine MN-14 light chain or heavy chain variable
region.
[0195] 68. The method of embodiment 65, wherein said humanized MN-14
antibody or fragment thereof comprises the light chain variable region as
set forth in FIG. 13A or 22A (hMN-14) or 23A and the heavy chain variable
region set forth in FIG. 14A-C or 22B (hMN-14) or 23B.
[0196] 69. The method of any of embodiments 56-68, wherein said fragment
is selected from the group consisting of F(ab).sub.2, F(ab').sub.2, Fab',
Fab, Fv and sFv.
[0197] 70. The method of any of embodiments 56-68, wherein said
therapeutic agent is selected from the group consisting of humanized,
chimeric, human or murine monoclonal antibody or fragment thereof
selected from the group consisting of a Class I anti-CEA monoclonal
antibody, Class II anti-CEA monoclonal antibody, Class III anti-CEA
monoclonal antibody, and a fragment thereof, and is administered either
concurrently or sequentially in a therapeutically effective amount.
[0198] 71. The method of embodiment 70, wherein said antibody or fragment
thereof is either naked or conjugated to another therapeutic agent.
[0199] 72. The method of any of embodiments 56-68, wherein said
therapeutic agent is selected from the group consisting of a naked
antibody, cytotoxic agent, a drug, a toxin, a radionuclide, an
immunomodulator, an antisense oligonucleotide, a photoactive therapeutic
agent, an immunoconjugate of a CEA or non-CEA antibody, a hormone, or a
combination thereof, optionally formulated in a pharmaceutically
acceptable vehicle.
[0200] 73. The method of embodiment 72, wherein said therapeutic agent is
selected from the group consisting of a humanized, chimeric, human or
murine monoclonal antibody or fragment thereof reactive with EGP-1, EGP-2
(e.g., 17-1A), MUC-1, MUC-2, MUC-3, MUC-4, PAM-4, KC4, TAG-72, EGFR,
HER2/neu, BrE3, Le-Y, A3, A33, Ep-CAM, AFP, Tn, Thomson-Friedenreich
antigens, tumor necrosis antigens, VEGF, PIGF or other tumor angiogenesis
antigens, Ga 733, IL-6, insulin-like growth factor-1, and a combination
thereof, and is administered to said subject either concurrently or
sequentially in a therapeutically effective amount.
[0201] 74. The method of embodiment 73, wherein said antibody or fragment
thereof is either naked or conjugated to another therapeutic agent.
[0202] 75. The method of any of embodiments 56-68, wherein said
therapeutic agent is not DTIC.
[0203] 76. The method of embodiment 72, wherein said cytotoxic agent is a
drug or a toxin.
[0204] 77. The method of embodiment 72, wherein said drug possesses the
pharmaceutical property selected from the group consisting of
antimitotic, alkylating, antimetabolite, antiangiogenic, apoptotic,
alkaloid, COX-2, and antibiotic agents and combinations thereof.
[0205] 78. The method of embodiment 76, wherein said drug is selected from
the group consisting of nitrogen mustards, ethylenimine derivatives,
alkyl sulfonates, nitrosoureas, triazenes, folic acid analogs,
anthracyclines, taxanes, COX-2 inhibitors, pyrimidine analogs, purine
analogs, antimetabolites, antibiotics, enzymes, epipodophyllotoxins,
platinum coordination complexes, vinca alkaloids, substituted ureas,
methyl hydrazine derivatives, adrenocortical suppressants, antagonists,
endostatin, taxols, camptothecins, doxorubicins and their analogs, and a
combination thereof.
[0206] 79. The method of embodiment 76, wherein said microbial, plant or
animal toxin is selected from the group consisting of ricin, abrin, alpha
toxin, saporin, ribonuclease (RNase), DNase I, Staphylococcal
enterotoxin-A, pokeweed antiviral protein, gelonin, diphtherin toxin,
Pseudomonas exotoxin, and Pseudomonas endotoxin.
[0207] 80. The method of embodiment 72, wherein said immunomodulator is
selected from the group consisting of a cytokine, a stem cell growth
factor, a lymphotoxin, a hematopoietic factor, a colony stimulating
factor (CSF), an interferon (IFN), a stem cell growth factor,
erythropoietin, thrombopoietin and a combination thereof.
[0208] 81. The method of embodiment 80, wherein said lymphotoxin is tumor
necrosis factor (TNF), said hematopoietic factor is an interleukin (IL),
said colony stimulating factor is granulocyte-colony stimulating factor
(G-CSF) or granulocyte macrophage-colony stimulating factor (GM-CSF)),
said interferon is interferons-.alpha., -.beta. or -.gamma., and said
stem cell growth factor is designated "S1 factor".
[0209] 82. The method of embodiment 72, wherein said immunomodulator
comprises IL-1, IL-2, IL-3, IL-6, IL-10, IL-12, IL-18, IL-21,
interferon-.gamma., TNF-.alpha. or a combination thereof.
[0210] 83. The method of embodiment 72, wherein said radionuclide has an
energy between 20 and 10,000 keV.
[0211] 84. The method of embodiment 83, wherein said radionuclide is
selected from the group consisting of .sup.125I, .sup.131I, .sup.90Y,
.sup.88Y, .sup.225Ac, .sup.177Lu, .sup.188Re, .sup.186Re, and
combinations thereof.
[0212] 85. The method of embodiment 72, wherein said photoactive
therapeutic agent is a chromogen or dye.
[0213] 86. The method of embodiment 77, wherein said alkylating agent is
dacarbazine.
[0214] 87. The method of embodiment 86, wherein said MN-14 antibody or
fragment thereof is administered in a dosage of 100 to 600 milligrams
protein per dose per injection.
[0215] 88. The method of embodiment 87, wherein said MN-14 antibody or
fragment thereof is administered in a dosage of 300-400 milligrams
protein per dose per injection.
[0216] 89. A method for treating cancer comprising administering to a
subject, either concurrently or sequentially, a therapeutically effective
amount of an anti-CEA antibody or fragment thereof and at least one
therapeutic agent, and optionally formulated in a pharmaceutically
acceptable vehicle.
[0217] 90. The method of embodiment 89, wherein the therapeutic agent is
CPT-11.
[0218] 91. The method of embodiment 90, wherein the anti-CEA antibody or
fragment is administered prior to administration of CPT-11.
[0219] 92. The method of embodiment 91, wherein the anti-CEA antibody or
fragment is administered around 3 days prior to administration of CPT-11.
[0220] 93. The method of embodiment 89, wherein the therapeutic agent is
DTIC.
[0221] 94. The method of embodiment 89, wherein the therapeutic agent is
oxaliplatin.
[0222] 95. The method of embodiment 89, wherein the therapeutic agent is
5-flourouracil/leucovorin.
[0223] 96. In a method of treating cancer with a non-antibody therapeutic
agent, the improvement comprising pre-treating a subject suffering from
cancer with an anti-CEA antibody or a fragment thereof prior to
administration of the non-antibody therapeutic agent.
[0224] 97. The method of embodiment 96, wherein the anti-CEA antibody is
hMN-14.
[0225] 98. The method of embodiment 96, wherein the therapeutic agent is
CPT-11.
[0226] 99. A method of treating cancer with an antibody comprising
administering to a subject suffering from cancer, prior to administration
of the antibody, an agent that activates granulocytes and/or NK cells in
order to increase effector function of the antibody.
[0227] 100. The method of embodiment 99, wherein the agent is GM-CSF.
[0228] 101. The method of embodiment 99, wherein the antibody is an
anti-CEA antibody.
[0229] 102. The method of embodiment 101, wherein the antibody is hMN-14.
[0230] 103. A method of treating cancer with an anti-CEA antibody or
fragment, comprising administering to a subject suffering from cancer,
prior to administration of the anti-CEA antibody or fragment, an amount
of interferon effective to up regulate CEA expression in tumor cells.
[0231] 104. The method of embodiment 103, wherein the anti-CEA antibody is
hMN-14.
[0232] 105. An antibody fusion protein comprising at least one CEA binding
site and at least one other binding site for the same or different
antigen.
[0233] 106. The antibody fusion protein according to embodiment 105,
wherein the CEA binding site binds to the same site as an MN-14 antibody.
[0234] 107. The antibody fusion protein according to embodiment 105, which
is bivalent and trivalent.
[0235] 108. The antibody fusion protein according to embodiment 105,
wherein one arm of the fusion protein is a Class III, anti-CEA MAb that
targets CD66e and another arm of the fusion protein is from another CEA
crossreactive antibody that targets CD66a-d.
[0236] 109. The antibody fusion protein according to embodiment 105,
wherein the binding arms are scFv or Fab regions.
[0237] 110. An antibody fusion protein according to embodiment 105, which
is a bispecific, trivalent protein comprising one arm reactive with
CD66a-d and two arms reactive with only CEA (CD66e).
[0238] 111. An antibody fusion protein according to embodiment 105, which
is a bispecific protein comprising two arms that bind to NCA50/90.
[0239] 112. An antibody fusion protein according to embodiment 105, which
is a diabody comprising one arm that binds to NCA50/90 and a second arm
that binds to a Class III epitope of CEA.
[0240] 113. An antibody fusion protein according to embodiment 112,
wherein the NCA-50/90 arm is obtained from an hMN-3 antibody and the
second arm that binds to a Class III epitope of CEA is obtained from
hMN-14.
[0241] 114. An antibody fusion protein according to embodiment 113,
wherein the fusion protein lacks an Fc-domain to prevent activation of
cytokine release from granulocytes or which has an Fc-domain that has
been modified to prevent complement fixation and ADCC.
[0242] 115. An antibody fusion protein according to embodiment 104, which
is a triabody comprising one hMN-3 arm and and two hMN14 arms. 115a. An
antibody fusion protein according to embodiment 104, which is a triabody
comprising one hMN-15 arm and and two hMN14 arms.
[0243] 116. An antibody fusion protein according to embodiment 104,
comprising at least one hMN-14 arm and at least one NP-3 arm.
[0244] 117. An antibody fusion protein according to embodiment 116, which
comprises an Fc-domain to enable complement fixation and activation of
ADCC.
[0245] 118. An antibody fusion protein according to embodiment 104,
further comprising a therapeutic agent.
[0246] 119. An antibody fusion protein according to embodiment 118,
wherein the therapeutic agent is a cytokine.
[0247] 120. An antibody fusion protein according to embodiment 119,
wherein the cytokine is interferon, a colony-stimulating factor, or an
interleukin.
[0248] 121. An antibody fusion protein according to embodiment 120,
wherein the colony-stimulating factor is GM-CSF or G-CSF.
[0249] The invention is further illustrated by, though in no way limited
to, the following examples.
EXAMPLE 1
Materials and Methods
Monoclonal Antibodies and Cell Lines
[0250] TT, a human medullary thyroid cell line, was purchased from the
American Type Culture Collection. The cells were grown as monolayers in
DMEM (Life Technologies, Gaithersburg, Md.) supplemented with 10% fetal
bovine serum, penicillin (100 U/ml), streptomycin (100 .mu.g/ml), and
L-glutamine (2 mM). The cells were routinely passaged after detachment
with trypsin, 0.2% EDTA.
[0251] MN-14 is a Class III anti-CEA MAb, reacting with CEA and unreactive
with the normal cross reactive antigen, NCA, and meconium antigen (Hansen
et al., Cancer, 71:3478(1993)). The construction and characterization of
the humanized forms of MN-14 and LL2, the anti-CD22 MAb used here as a
negative control, have been previously described. (Sharkey et al., Cancer
Res., 55:5935s (1995); Leung et al., Mol. Immunol., 32:1416 (1995)).
P3x63Ag8 (MOPC-21) is an irrelevant mouse myeloma IgG.sub.1 obtained from
the American Type Culture collection (Rockville, Md.). The antibodies
were purified by protein A chromatography.
[0252] In Vivo Studies
[0253] Tumors were propagated in female nu/nu mice (Taconic Farms,
Germantown, N.Y.) at 6-8 weeks of age by s.c. injection of
2.times.10.sup.8 washed TT cells, which had been propagated in tissue
culture. Antibodies were injected i.v., via the lateral tail vein, into
the tumor-bearing animals. Details on the quantities of antibodies
injected and the time of administration are indicated in the Results
section for each study. Results are given as tumor volumes of individual
animals as well as the mean.+-.SE. Tumor size was monitored by weekly
measurements of the length, width, and depth of the tumor using a
caliper. Tumor volume was calculated as the product of the three
measurements. Statistical comparisons were made using the Student's
T-test to compare tumor volumes and area under the growth curves.
EXAMPLE 2
Combination Therapy of Naked hMN-14 and DTIC Delivered 2 Days After
Injection of TT (Human Medullary Thyroid) Tumor Cells
[0254] In a previous study, naked hMN-14 and dacarbazine (DTIC) were given
in combination to TT 2 days after tumor implantation, using 100 .mu.g and
25 .mu.g doses of DTIC (days 2, 3, and 4) and 250 .mu.g doses of hMN-14
given on day 2, then weekly. The 100 .mu.g DTIC dose combined with hMN-14
was more effective than either treatment alone (FIG. 1A). However, the
100 .mu.g DTIC dose yielded too strong a response, while the 25 .mu.g
dose was not effective. Surprisingly, the effects of MN-14 alone and DTIC
alone were not additive. In other words, given the results of treatment
with 250 .mu.g hMN-14 alone and 100 .mu.g DTIC alone, one would not
predict that the combination of 250 .mu.g hMN-14 and 100 .mu.g DTIC would
have such a pronounced effect. See FIG. 1A.
[0255] In this study, treatment began 2 days after TT cell injection, as
in the previous study. hMN-14 was given at 100 .mu.g/dose on days 2, 3,
4, 5, 7, 8, 9, 10, 11, 15 and 22, then every 7 days until the animal
died, the tumor attained a volume of 2.0 cm.sup.3 or the study terminated
for humane reasons. Doses of DTIC were 50 and 75 .mu.g per dose, which is
between the doses given in the previous study. TT cells were injected
subcutaneously in 60 nude mice. The day of injection was Monday, day 0.
See FIG. 1B.
[0256] Results demonstrate that significant delays in tumor growth were
caused by either MAb therapy alone or chemotherapy alone (FIG. 1B). The
75 .mu.g dose of DTIC in combination with this schedule of hMN-14
antibody was significantly more effective than either treatment alone
(p<0.02). Unexpectedly, the results of combined DTIC and MAb therapy
were not additive. At 7 weeks, 8/10 mice in the 75 .mu.g DTIC and MAb
group had no palpable tumor, compared to 1/10 mice in the 75 .mu.g DTIC
only group and 0/10 mice in the untreated and MAb group.
[0257] Mean tumor volumes at 7 weeks were 0.018.+-.0.039 cm.sup.3 (75
.mu.g DTIC plus MN-14), 0.284+0.197 cm.sup.3 (75 .mu.g DTIC only),
0.899.+-.0.545 cm.sup.3 (hMN-14 only) and 1.578.+-.0.959 cm.sup.3
(untreated). Combined therapy of the naked anti-CEA antibody with DTIC
augments the anti-tumor effects of antibody or chemotherapy alone,
without increased toxicity. The superiority of the combined modality
treatment was surprising.
[0258] Dosing Summary: (1) hMN-14 was given daily (i.p.), except Sundays,
at 100 .mu.g/dose/mouse on days 2 through 11. The antibody treatment was
initiated on the same day as DTIC treatment. (2) DTIC was given on days
2, 3, and 4 at 50 and 75 .mu.g/dose, which corresponded to 5% and 7.5% of
the MTD. Only one course of DTIC was given.
[0259] Groups: 6 groups of mice, each group containing 10 mice.
[0260] Group 1: Untreated.
[0261] Group 2. DTIC at 50 .mu.g/dose, days 2, 3, and 4 (Wednesday,
Thursday, and Friday).
[0262] Group 3. DTIC at 75 .mu.g/dose, days 2, 3, and 4.
[0263] Group 4. DTIC at 50 .mu.g/dose, days 2, 3, and 4, plus hMN-14 (100
.mu.g/dose) day 2, 3, 4, 5, 7, 8, 9, 10, 11, 15 and 22, then every 7 days
until the animal died, the tumor attained a volume of 2.0 cm.sup.3, or
the study terminated.
[0264] Group 5. DTIC at 25 .mu.g/dose, days 2, 3, and 4, plus hMN-14 (100
.mu.g/dose) day 2, 3, 4, 5, 7, 8, 9, 10, 11, 15 and 22, then every 7 days
until the animal died, the tumor attained a volume of 2.0 cm.sup.3, or
the study terminated.
[0265] Group 6. hMN-14 (confirm 100 .mu.g/dose), days 2, 3, 4, 5, 7, 8, 9,
10, 11, 15 and 22, then every 7 days until the animal died, the tumor
attained a volume of 2.0 cm.sup.3, or the study terminated.
[0266] Animals were monitored for survival. Tumor and body weight were
measured weekly.
[0267] Protocol: On day 2, 200 mg/vial DTIC was reconstituted with 19.7 ml
sterile water for injection. The resulting solution contained 10 mg/ml of
dacarbazine with a pH range of 3.0-4.0. The solution was used as needed
for the dilutions described below and the remainder was frozen in 1 ml
aliquots for subsequent use.
[0268] Groups 2 and 4: 5 ml of 0.5 mg/ml solution was prepared. 100 .mu.l
of 0.5 mg/ml/mouse was injected i.v.
[0269] Groups 3 and 5: 5 ml of 0.75 mg/ml solution was prepared. 100 .mu.l
of 0.75 mg/ml/mouse was injected i.v.
[0270] Quantity of hMN-14 was estimated. 100 .mu.l of 1 mg/ml hMN-14 was
injected i.p. in mice in Groups 4, 5 and 6.
EXAMPLE 3
Radioimmunotherapy Studies in a Human MTC Xenograft Model
[0271] Applicants developed a model for experimental radioimmunotherapy of
MTC with radiolabeled anti-CEA MAbs using human MTC xenografts of the
CEA-and calcitonin producing human MTC cell line designated TT ([Stein,
1999 #82], see Appendix). MTC tumors were established in nude mice by a
s.c. inoculation of 2.times.10.sup.8 cells and allowed to grow for 2-5
weeks before injection of MAbs. Biodistribution and RAIT studies were
then carried out with MN-1 4, which was shown by flow cytometry to react
with TT cells. Both Ag8 and Mu-9 were used as negative control MAbs in
these studies. Preliminary studies using smaller tumors of .about.0.08 g
showed that 7 days after the injection of .sup.131I-MN-14, the percent of
injected dose per gram of tumor (% ID/g) was 68.9% compared with only
12.6% ID/g for the co-injected .sup.125I-Ag8 control. Using larger
tumors, (grown for five weeks in nude mice; mean tumor weight=0.404 g),
the % ID/g of tumor observed at seven days post injection of
.sup.125I-MN-14 was 12.4%. However, the % ID/g of the co-injected
.sup.88Y-MN-14 was 50.5%, or 4.1-fold higher than .sup.125I-MN-14. The
tumor-to-blood, lungs, liver, spleen, and kidneys were also higher with
.sup.88Y-MN-14 than with .sup.125I-MN-14, while the tumor-to-bone ratios
were equal with both agents. When .sup.125I-MN-14 and .sup.88Y-MN-14
biodistribution data were used to predict the tumor dosimetry with 14 and
.sup.90Y-MN-14, respectively, the radiation absorbed dose delivered at
the MTD of .sup.90Y-MN-14 (115 .mu.Ci) was 1.75-fold higher than that
delivered at the MTD of .sup.131I-MN-14 (275 .mu.Ci) (4900 cGy vs. 2800
cGy).
[0272] Therapy studies in this model confirmed that .sup.90Y-MN-14 is a
better therapeutic agent than .sup.131I-MN-14. In 5-week-old tumors, a
5-week complete inhibition of tumor growth was seen at the MTD of
.sup.90Y-MN 14 compared to only a tumor growth delay with .sup.131I-MN-14
(FIG. 2). Moreover, when smaller 2-week old tumors were treated, an
average of 60% tumor volume reduction, with some complete tumor
regressions, was seen at the MTD of .sup.90Y-MN-14. These anti-tumor
effects were very significant compared with the relatively rapid tumor
growth in untreated animals or those treated at the MTD of control MAbs.
Thus, our preclinical studies demonstrated that this animal model is
exquisitely suitable for experimental RAIT with anti-CEA MAbs.
[0273] The longer path length and higher energy of .sup.90Y compared with
.sup.131I, in addition to the fact that .sup.90Y is retained longer by
target cells led to delivery of an increased radiation dose to tumor and
thus more effective therapy at equitoxic doses. If our results with
residualizing .sup.131I (refs) can be generalized to MN-14 in MTC, we
would expect that residualizing .sup.131I would be at least equally
effective to .sup.90Y in tumors of the size studied here, and most likely
superior in the setting of micrometastatic disease or as adjuvant therapy
following surgery.
EXAMPLE 4
[0274] Chemotherapy
[0275] Four drugs, doxorubicin, DTIC (dacarbazine), cyclophosphamide, and
vincristine, were evaluated, singly and in combination, for their effect
on the growth of TT MTC xenografts in nude mice. Doses were selected
based on the doses of each drug given clinically to humans on a
mg/m.sup.2 basis. Animals were monitored for survival, and tumor volumes
and body weights were measured weekly. FIG. 3 shows the tumor growth
curve for animals in this study. Given individually, doxorubicin, DTIC
and cyclophosphamide, but not vincristine, yielded significant growth
inhibition, although the growth delay caused by DTIC was markedly longer
than that of the other drugs. Approximate mean time to doubling for each
group was: untreated, 1 week; doxorubicin, 2.5 weeks; DTIC, 7.5 weeks;
cyclophosphamide, 3 weeks; and vincristine, 1.5 weeks. Combining
doxorubicin and DTIC improved the efficacy compared to either drug alone,
increasing the mean time to doubling to 10 weeks. However, the increased
efficacy of doxorubicin and DTIC combination did not reach the 95%
confidence level in comparison to DTIC alone. The P values for AUC
comparisons were as follows: P<0.01 for doxorubicin+DTIC versus
doxorubicin, and P<0.1 for doxorubicin+DTIC versus DTIC. The 4-drug
regimen extended the mean time to doubling to 12 weeks; P<0.01 for
comparisons to both doxorubicin and DTIC.
[0276] Log rank analysis of survival data for the individual drugs versus
the untreated group indicated a significant difference only for DTIC and
cyclophosphamide. Mean survival time for the untreated control group was
4 weeks compared to 11 weeks and 8 weeks for DTIC and cyclophosphamide
treatment groups, respectively, and greater than 12 weeks for the drug
combinations. Toxicity, as measured by body weight loss, was within the
acceptable range for all study groups. Maximum weight loss was observed 1
week after treatment in the mice treated with all 4 drugs, ranging from
3-12% loss of body weight.
EXAMPLE 5
Combining Radioimmunotherapy and Chemotherapy for Treatment of MTC
[0277] RAIT Plus 4-drug Combination.
[0278] The effect of combining RAIT with .sup.90Y-anti CEA MAb MN-14 and
the 4-drug combination was evaluated by comparing the growth of TT in
untreated mice to those treated with the 4-drug regimen described above
(doxorubicin, DTIC, cyclophosphamide, and vincristine), 100% of the
maximum tolerated dose (MTD) of RAIT (105 .mu.Ci), 50% of the MTD of
RAIT, and 50% of the MTD of RAIT combined with the 4 drugs. FIG. 4 shows
the growth curves of TT tumors in mice given the various treatment
regimens. All four of the treatment groups yielded significant
improvement in efficacy compared to the untreated animals. Whereas the
approximate mean time to doubling in the untreated animals was 1.5 weeks,
chemotherapy with the 4 drugs extended the mean doubling time to 10 weeks
and RAIT alone yielded 4-week and 8-week doubling times at 50% and 100%
of the MTD, respectively. As expected, both the 100% RAIT group and the
4-drug therapy regimen were significantly better than the 50% RAIT group.
Most importantly, combining 50% RAIT and the 4-drug regimen yielded
improved results, compared to either therapy alone, further extending the
mean doubling time to approximately 12.5 weeks. For the comparison of the
combined treatment to the 4-drug regimen, P<0.02, and for the
comparison to 100% RAIT, P<0.01.
[0279] Mean weight loss 1 week post treatment (nadir) was 9% for the 100%
RAIT and the 4-drug regimens, but 15% for combined 50% RAIT plus 4-drug
treatment. In addition, in the combined therapy group, one animal died
three weeks post treatment and a second animal had a weight loss greater
than 20%. Thus, this treatment exceeded the maximum tolerated dose.
[0280] RAIT Plus Chemotherapy with 2-Drug Regimens.
[0281] The effect of combining RAIT with .sup.90Y-anti CEA MAb MN-14 and
chemotherapy with a 2-drug combination, consisting of doxorubicin and
DTIC, was also evaluated in this MTC xenograft model. Approximate
doubling times for the groups were: untreated, 1.5 weeks; doxorubicin
plus DTIC, 8 weeks; the MTD of RAIT, 10 weeks; and the MTD of RAIT
combined with 25-75% of the 2-drug regimen, greater than 12 weeks. Thus,
RAIT alone was more effective than the 2-drug regimen and, most
significantly, combining RAIT and the 2-drug regimen yielded improved
results compared to either therapy alone. For the comparison of the
combined treatment to the 2-drug regimen, P<0.005, for the comparison
to RAIT alone, P<0.02.
[0282] Mean weight loss 1-2 weeks post treatment (nadir) was 2-8% for all
groups, except the 100% RAIT plus 75% 2-drug chemotherapy group, where a
13% loss was observed at 2 weeks. In addition, in this combined therapy
group, two animals died 3-4 weeks post treatment and one experienced a
weight loss greater than 20%. Thus, addition of the 75% dose level of
doxorubicin and DTIC to 100% RAIT treatment exceeded the MTD, whereas 50%
of this 2-drug combination can be tolerated in combination with 100%
RAIT.
[0283] RAIT Plus Doxorubicin.
[0284] Because previous publications have reported the combination of RAIT
with doxorubicin in this model (Stein et al., Clin Cancer Res., 5:3199s
(1999); Behr et al., Cancer Res. 57:5309 (1997)), a direct comparison was
made to the RAIT plus doxorubicin regimen. A direct comparison was also
made to RAIT plus the 4-drug regimen. All treatments yielded significant
efficacy compared to the untreated animals. The mean doubling time for
the RAIT plus doxorubicin group was 12 weeks. In this study combining the
full MTD of RAIT with either 50% of doxorubicin and DTIC or the 4-drug
regimen extended the mean doubling time to greater than 15 weeks, with no
statistically significant difference between these two groups. A
substantial number of objective responses were observed in these studies.
Following treatment with RAIT plus doxorubicin there were 3 complete
responses, 2 partial responses, and 5 animals with stable disease for at
least 4 weeks, out of a total of 10 mice. The RAIT plus 2-drug protocol
increased the objective responses to 10 complete responses and 2 partial
responses of 12 animals, and the RAIT plus 4-drug treatment protocol led
to 7 complete responses and 2 partial responses out of 9 mice.
[0285] RAIT Plus DTIC.
[0286] Because DTIC was the most effective chemotherapeutic agent when
administered alone, the efficacy of RAIT plus DTIC was evaluated in
comparison to that of RAIT plus doxorubicin and DTIC. Omitting
doxorubicin from the treatment protocol will be important for clinical
application in order to avoid the added toxicity of this drug, especially
the known cardiac toxicity. As shown in FIG. 5, the two study groups
which received the chemotherapy in combination with RAIT, either
doxorubicin and DTIC or DTIC only, are approximately equal to each other,
and both are more effective than the single modality treatments. P values
for AUC comparisons were as follows: P<0.01 for RAIT+DTIC versus DTIC,
and P<0.05 for RAIT+DTIC versus RAIT. The mean doubling time for the
RAIT plus DTIC, and RAIT plus doxorubicin and DTIC groups were 15.5 weeks
and 14 weeks, respectively, compared to 7.5 weeks and 9 weeks for DTIC
and RAIT alone, respectively. Thus, the combined modality treatment of
RAIT plus DTIC extended the mean time to doubling by 100% over the DTIC
chemotherapy. No significant difference was observed by either AUC or log
rank analyses between the RAIT plus DTIC, and RAIT plus doxorubicin and
DTIC groups.
EXAMPLE 6
[0287] Studies with Naked Anti-CEA Alone
[0288] Therapy with Naked hMN-14
[0289] To study the effect of unlabeled hMN-14 on the growth of TT tumors
in nude mice, a single injection of hMN-14 was administered i.v. either
one day or eleven days post tumor cell injection. FIG. 6 shows the tumor
growth curves of animals treated with 0.5 mg hMN-14/mouse compared to
untreated controls. The untreated group contained 16 animals; the two
treatment groups contained 10 animals each. A significant growth delay
was observed between the untreated group and the group treated on day-1
post tumor injection. Significant differences in the mean tumor sizes
(p<0.05) were observed from day-32 through day-93. Between day-32 and
day-60 there was a 64-70% inhibition of tumor size in the MN-14 treated
group compared to the untreated animals. There were no significant
differences between the mean tumor sizes in the day-11 group and
untreated animals. Significant delay in tumor growth was also seen by
t-test analysis of the area under the growth curves. P<0.05 for the
untreated group compared to the group treated one day following tumor
injection, but not for the group treated eleven days following tumor
injection.
[0290] Specificity of Treatment
[0291] FIG. 7 summarizes the results of a study on the specificity of the
anti-tumor response. The effect of unlabeled hMN-14 on the growth of TT
tumors in nude mice was compared to that of a negative control humanized
MAb, hLL2 (anti-CD22), and the murine MN-14. MAbs (0.5 mg/mouse) were
administered (i.v.) one day after TT cells, then three additional weekly
doses of 0.5 mg/mouse were given. Groups of 15 animals were studied. The
growth inhibition observed in the first study from treatment with 0.5 mg
hMN-14 was confirmed in this study. Significant differences in mean tumor
sizes (p<0.05) between the hMN-14 and the untreated group were
observed starting at day-23. At day-37 the mean tumor volume in the group
treated with hMN-14 was 42.7% of the untreated control animals. Treatment
with murine MN-14 yielded results similar to the hMN-14. Treatment with
hLL2 did not slow tumor growth; instead there was a small (not
significant) increase in growth rate. For example, at day-37 87% of the
tumors treated with hMN-14 were less than 0.5 cm.sup.3, compared to 40%
of the untreated and 29% of the hLL2 treated group. T-test analysis of
the area under the growth curves demonstrated significant differences
(p<0.05) between the untreated group and the groups treated with
either hMN-14 or murine MN-14, but not the group treated with hLL2. In
addition, the hMN-14 group was significantly different from the hLL2
group but not the murine MN-14 treated animals.
[0292] Effect of Dose
[0293] To study the effect of dose of unlabeled hMN-14 on the growth of TT
tumors in nude mice, increasing doses of hMN-14 were evaluated. Antibody
doses were administered 1 day after TT cells, then weekly until the
termination of the study. Weekly doses ranged from 0.125 mg to 2.0 mg
hMN-14/mouse in groups of six mice. Significant differences in mean tumor
sizes and area under the growth curves between the untreated group and
all treatment groups were observed (FIG. 8). For example, between day-21
and day-49 mean tumor volume in the 2 lowest hMN-14 treatment groups were
27-40% of the size of tumors in the untreated animals. Treatment with the
lower doses, 0.125 mg and 0.25 mg, appeared to be more effective than
treatment with the higher doses, although the difference did not reach
statistical significance.
[0294] Timing
[0295] The effect of time between TT injection and initial dose of hMN-14
on the growth of TT tumors in nude mice was evaluated by varying the day
of administration of MAb. hMN-14 (0.25 mg) was administered either 1, 3,
or 7 days after TT cells, then weekly until termination of the study.
Groups of 7-8 animals were studied. Results are summarized in FIG. 9.
Significant differences in mean tumor sizes (p<0.05) between the
untreated group and all three treatment groups were observed. However,
the difference in mean tumor size between the untreated mice and the
day-7 treatment group was only significant at one time point, day-28.
Day-1 treated mice yielded significant differences from 21-77 days, and
day-3 treated mice yielded significant differences from 21-70 days.
T-test analysis of the area under the growth curves indicated significant
growth inhibition for the groups treated with hMN-14 either 1 or 3 days
after TT cell administration compared to untreated group. This analysis
did not reach the 95% confidence limit for difference between the
untreated group and the group treated on day-7 (p=0.057 at 5 weeks).
EXAMPLE 7
[0296] Combined Naked Anti-CEA Plus DTIC Therapy of MTC
[0297] To study whether naked hMN-14 can add to the efficacy of DTIC, TT
bearing nude mice were given DTIC (75 .mu.g/dose) in combination with a
course of treatment of the unlabeled MAb. DTIC was administered for 3
consecutive days at 75 .mu.g/dose as one course, beginning 2 days after
s.c. injection of TT cells. hMN-14 MAb treatment was initiated on the
same day as the first dose of DTIC, at 100 .mu.g/dose/day for 5 days in
the first two weeks, then twice weekly. Significant delays in tumor
growth were caused by these schedules of either MAb therapy or
chemotherapy alone (FIG. 10). The 75 .mu.g dose of DTIC in combination
with this schedule of hMN-14 was significantly more effective than either
treatment alone (P<0.02). At 7 weeks, 8/10 mice in the 75 .mu.g
DTIC+MAb group had no palpable tumor, compared to 1/10 in the 75 .mu.g
DTIC-only group and 0/10 in the untreated and MAb-only groups. Mean tumor
volumes at 7 weeks were 0.018+0.039 cm.sup.3 (75 .mu.g DTIC+hMN-14),
0.284+0.197 cm.sup.3 (75 .mu.g DTIC), 0.899+0.545 cm.sup.3 (hMN-14) and
1.578+0.959 cm.sup.3 (untreated).
[0298] The anti-CEA MAb MN-14 has shown unexpected anti-tumor efficacy in
MTC without conjugation to a cytotoxic agent. Differences in mean tumor
sizes between the hMN-14 treated and the untreated groups were observed
beginning at 3 weeks and lasting at least 2 months. Treatment with
isotype matched negative control MAbs did not slow tumor growth. This is
the first evidence of tumor suppression with a "naked" anti-CEA MAb.
However, combined therapy of the naked anti-CEA MAb with DTIC augments
the anti-tumor effects of antibody or chemotherapy alone, without
increased toxicity. The superiority of the combined modality treatment
argues for the integration of CEA-MAb therapy into chemotherapeutic
regimens for MTC management.
EXAMPLE 8
[0299] FIG. 15 shows the effects of naked hMN-14 CEA MAb and DTIC
treatment in a medullary thyroid cancer model. Treatment was initiated
2-days after tumor transplantation. DTIC was administered at-75 .mu.g on
days 2, 3, and 4 at 7.5% of the MTD to mice. hMN-14 was administered at
100 .mu.g/day on days 2-5, 7-10, 11, 15, 22, and then once per week. The
results show a statistically significant difference (P<0.05) between
the areas under the curve for all groups. Naked hMN-14 CEA MAb treatment
showed a significant effect on inhibiting tumor growth. When combined
with DTIC, a surprisingly enhanced level of inhibition of tumor growth
occurred relative to either treatment alone.
EXAMPLE 9
Naked Anti-CEA Antibody Treatment Plus CPT-11 or 5-FU in Colon Cancer
Cells
[0300] The present experiment discloses the in vitro and in vivo effect of
a humanized, naked anti-CEA, hMN-14 antibody (hMN-14) alone, and in
combination with chemotherapy on colon cancer growth.
Methods and Materials
[0301] Antibody Production. The CDR-grafted (humanized) MN-14 (hMN-14)
anti-carcinoembryonic antigen (CEA) (Sharkey, R. M., et al., Cancer Res,
55: 5935-5945, 1995) along with the murine MN-14 and other antibodies
targeting different CEA epitopes (NP1, NP3, MN3, MN15; (Sharkey, R. M.,
et al., Cancer Res, 50: 2823-2831, 1990) were purified by protein A and
ion-exchange chromatography (Q-Sepharose; Pharmacia, Piscataway, N.J.).
Purity was tested by immunoelectrophoresis, polyacrylamide gel
electrophoresis using reducing and non-reducing conditions and
size-exclusion high-pressure liquid chromatography.
[0302] In Vivo Therapy Studies. Survival therapy studies were performed
using a CEA-positive GW-39 intrapulmonary micrometastasis model (Sharkey,
R. M., et al., J Natl Cancer Inst., 83: 627-632, 1991; Blumenthal, R. D.,
et al., Cancer Res, 52: 6036-6044, 1992). Stock subcutaneous GW-39 human
colorectal tumors were used to prepare a 10% or 5% cell suspension. Cells
(30 .mu.l) were injected i.v. into the caudal vein. HuMN-14 IgG was
initiated on either day 0 or day 3 after cell implantation and
administered daily.times.14 days and twice weekly thereafter for the
duration of the study at a dose of 100 .mu.g/d. CPT-11 was administered
at a dose of 160 .mu.g daily for 5 days i.p. (20% of the MTD) starting on
day 0 or day 3 after cell implantation. For some studies, the stock GW-39
tumor came from mice that received 100,000 U of IFN.gamma. twice daily
for 4 days to upregulate CEA expression (Greiner, J. W., et al., 16:
2129-2133, 1996), which was confirmed by immunohistology as previously
described (Blumenthal, R. D., et al., Int. J. Cancer, 51: 935-941, 1992).
Body weight was monitored weekly and animal survival recorded. Results
were analyzed with the Kaplan-Meir test and median survival time
determined.
[0303] In Vivo Effects of Antibody-Induced Chemosensitization of Cancer
Cells.
[0304] The effect of hMN14-induced chemosensitization was apparent in vivo
as well as in vitro. Survival curves for mice bearing GW-39
intrapulmonary micrometastases, as described above, and untreated or
treated with hMN14 alone (100 .mu.g/d.times.14 d and twice weekly for the
duration of the study), a 10% MTD of CPT-11 (80 .mu.g/d.times.5 days)
alone or both modalities together. Treatment was initiated the day of
cell implantation (30 .mu.l of a 10% GW-39 cell suspension). Each
treatment group started with 10 mice and the study was repeated twice.
The results show that co-administration of hMN-14 and CPT-11 to nude mice
bearing GW-39 lung micrometastases increases survival beyond the effect
of either modality alone. Administration of a 10% MTD of CPT-11 resulted
in a 1-week increase in median survival from 56 days to 63 days
(p<0.05). Median survival time of animals dosed with both hMN-14 and
CPT-11 on day 0 increased by an additional 2 weeks to 77 days (p<0.005
compared with untreated mice). Since maximal antibody accretion occurs 3
days post injection, hMN-14 treatments were initiated 3-days before
CPT-11 to determine whether such dosing would further enhance the
therapeutic effect of the combined modality treatment approach by
allowing high antibody uptake and chemosensitization in vivo. The results
demonstrate that the 3-day pretreatment with hMN-14 followed by CPT-11
increased median survival to 105 days (p<0.001), compared with CPT-11
alone on day 3, with a median survival of 70 days. In this study,
co-treatment of hMN-14 and CPT-11 was superior, as evidenced by a median
survival of 70 days vs. CPT-11 alone on day 0, with a median survival of
63 days or untreated mice with a median survival of 35 days. The results
were similar for a further experiment where a 5% GW-39 cell suspension
was used instead of the 10% GW-39 cell suspension.
EXAMPLE 10
In Vivo Effect of Pretreatment with an Immunomodulator Prior to Treatment
with hMN-14 and CPT-11 on Tumor Cell Chemosensitivity
[0305] A further experiment evaluated the combined treatment of hMN-14
with CPT-11, initiated together in mice with GW-39 tumors expressing
higher CEA levels, as a result of pretreatment of GW-39 stock tumors (10%
GW-39 cell suspension) with interferon-.gamma. (IFN.gamma.). The
experiments involving interferon-gamma enhancing the antitumor effects of
naked CEA antibody (hMN-14) were conducted as follows.
[0306] First, GW-39 human colon cancer was grown subcutaneously in a mouse
that received 100,000 units of IFN-gamma twice a day for 4 days. A
control mouse with GW-39 tumor was not given IFN. Experimental mice were
injected i.v. with a 5% suspension of GW-39 (w/v) from either of the two
mice (i.e., with or without IFN treatment) into two groups of eight. Four
of each received tumor from the IFN-treated mice and four from the
untreated mice. One group of 8 mice then received hMN-14 (100 ug per
day.times.14 days and then twice weekly thereafter until expt was ended),
another group CPT-11 at 160 ug/day.times.5 days (=20% of maximum
tolerated dose), a third group received the same doses of antibody+drug
combined, and a fourth group that was not treated at all. Animal weights
were measured and survival determined weekly. Also, samples of stock
tumor treated with IFN in the mice that were later implanted were also
processed for immunohistology to assess increase in CEA expression in the
tumors from mice treated with IFN-gamma, and this was controlled by also
treating the suspensions by immunohistology with an irrelevant IgG, such
as Ag8, which showed no CEA staining.
EXAMPLE 11
[0307] A comparison was performed of the effects of naked hMN-14 CEA Mab
on low and high (induced by interferon-gamma, as described earlier)
CEA-expressing tumor cells in an animal model. The results demonstrate
that increased expression of CEA antigen on tumor cells correlates with
improved efficacy of anti-CEA antibody. The results of the comparison
study are shown in FIG. 21. Thus, interferon-gamma pre-treatment is
useful to boost the efficacy of anti-CEA antibody therapy in the
treatment of cancer.
EXAMPLE 12
Sigmoid Colon Cancer Therapy with CEA Antibody and GM-CSF
[0308] J. R. is a 62-year-old man who is refractive to chemotherapy with
5-fluorouracil and leukovorin to reduce his metastases to the liver found
at the time of discovery and removal of his sigmoid colon cancer. His
plasma titer of carcinoembryonic antigen (CEA) at presentation is 34
ng/mL, and computed tomography of the liver shows several small lesions
measuring between 2 and 4 cm in diameter in the right lobe; other
radiological studies appear to be normal. Immunotherapy with humanized
anti-CEA IgG.sub.1, hMN-14, monoclonal antibody is begun on a weekly
basis for 4 weeks, at an intravenous dose of 300 mg/m.sup.2) infused over
2 hours. One week prior to hMN-14 therapy, the patient receives 2
subcutaneous injections of 200 mcg/m.sup.2 GM-CSF (sargamostim,
Leukine.RTM.), 3 days apart, and continued twice weekly during the 4
weeks of hMN-14 therapy. After these four weeks, both hMN-14 and GM-CSF
are given at the same doses every other week for an additional 3 months,
but the dose of GM-CSF is increased to 250 mcg/m.sup.2. Prior to each
administration of the humanized CEA antibody, the patient is given
diphenhydramine (Benadryl.RTM.), 50 mg orally, and acetaminophen
(Tylenol.RTM.), 500 mg orally. At this time, the patient is restaged,
with CT measurements made of the liver metastases and diverse
radiological scans of the rest of the body. Blood is also taken for
chemistries and for determination of his blood CEA titer. No areas of
disease outside of the liver are noted, but the sum of the diameters of
the measurable tumors in the liver appear to decrease by 40 percent, and
the patient's blood CEA titer decreases to 18 ng/mL, thus indicating a
therapeutic response. Immunotherapy with hMN-14 and GM-CSF, given once
every other week at 200 mg/m.sup.2 for hMN-14 and 250 mcg/m.sup.2 for
GM-CSF, are administered for another 2 months, and restaging shows
additional decrease in the sum of the diameters of the liver tumors and a
fall in the CEA titer to 10 ng/mL. Since tumor decrease is measured as
being >65% over the pre-therapy baseline, the therapy is considered to
have provided a partial response. After this, the doses were made less
frequent, once every month for the next six months, and all studies
indicate no change in disease. The patient is then followed for another
10 months, and remains in a partial remission, with no adverse reactions
to the therapy, and generally without any symptoms of disease.
EXAMPLE 13
Combined Immunotherapy and Chemotherapy of Metastatic Colon Cancer
[0309] S. T. is a 52-year-old woman presenting with liver and lung
metastases of colon cancer following resection of the primary tumor. She
is placed on a combined chemotherapy and immunotherapy protocol based on
the Gramont schedule (A. de Gramont et al., J Clin Oncol. 2000;
18:2938-1947), but with the addition of humanized anti-CEA monoclonal
antibody IgG.sub.1. Prior to infusions of the antibody, she receives 50
mg orally of diphenhydramine (Benadryl.RTM.) and 500 mg orally of
acetaminophen (Tylenol.RTM.). She receives a 2-hr infusion of leucovorin
(200 mg/m.sup.2/day) followed by a bolus of 5-fluorouracil (400
mg/m.sup.2/day) and 22-hour continuous infusion of 5-fluorouracil (600
mg/m.sup.2/day) for 2 consecutive days every 2 weeks, together with
oxaliplatin at 85 mg/m.sup.2 as a 2-hr infusion in 250 mL of dextrose 5%,
concurrent with leukocorin on day 1 (FOLFOX4 schedule). The patient also
receives anti-emetic prophylaxis with a 5-hydroxyltryptamine-3-receptor
antagonist. One week prior to this 2-week chemotherapy cycle, hMN-14
monoclonal anti-CEA antibody is infused over 2 hrs at a dose of 200
mg/m.sup.2, and repeated each week of the 2-week chemotherapy cycle, and
every week thereafter for the next month with another chemotherapy cycle.
Also, a subcutaneous dose of 5 mcg/kg/day of G-CSF (filgrastim,
Neupogen.RTM.) is administered once weekly beginning with the second
chemotherapy cycle, and continued at this dose for the duration of
immunotherapy with hMN-14 antibody, over the next 3 months. A total of 5
cycles of chemotherapy with continued administration of hMN-14 antibody
and filgrastim. Thereafter, hMN-14 and filgrastim therapy is given, at
the same doses, every other week for the next 3 months, without
chemotherapy. The patient is staged 2 months later, and her liver and
lung metastases show shrinkage by computed tomography measurements of
>80 percent of disease measured in the liver and lungs, as compared to
the measurements made prior to therapy. Her blood CEA titer also shows a
drop from the pre-therapy level of 63 ng/mL to 9 ng/mL. She is followed
over the next 6 months, and her disease appears to be stable, with no new
lesions found and no increase in the disease remaining in the liver and
lungs. The patient's predominant toxicity is peripheral sensory
neuropathy, which consists of laryngeopharyngeal dysesthesia. The patient
also experiences diarrhea, mucositis, nausea and vomiting during the
chemotherapy cycles, but these are not excessive. She does not experience
any adverse events when only immunotherapy is administered, and is able
to return to full-time activities without any significant restrictions.
EXAMPLE 14
[0310] FIG. 16 shows the effects of naked hMN-14 CEA Mab and CPT-11
treatment in an advanced colon cancer model. hMN-14 was given to mice at
a dose of 100 .mu.g/day over 14 days and then 2 times/week thereafter,
starting on day 0 after tumor implantation. CPT-11 was given at 60
.mu.g/day over 5 days. No effect of hMN-14 by itself is apparent under
these conditions, and only a modest effect of CPT-11 (p<0.05) was
observed. However, hMN-14 increases the effect of CPT-11, as seen by
comparing the CPT-11 median survival of 63 days vs. combination therapy
median survival of 77 days (p<0.005). Combination therapy with hMN-14
CEA Mab and CPT-11 significantly prolongs survival of an animal with
advanced human colonic tumor metastasis.
EXAMPLE 15
[0311] FIG. 17 shows the effects of naked hMN-14 CEA MAb and CPT-11
treatment in a low tumor burden cancer model. In a reduced tumor burden
model utilizing a 5% tumor cell suspension, CPT-11, hMN-14 alone, and
combination therapy of hMN-14+CPT-11 were compared. Dosages were as
indicated in Example 14. There was no apparent effect of hMN-14 alone
under these conditions. CPT 11 alone resulted in a median survival time
of 70 days. By contrast, the combination therapy produced a median
survival time of 91 days (p<0.025). The combination of hMN-14 and
CPT-11 significantly prolongs survival of animals with low tumor burden
in a metastatic model of human colonic cancer.
EXAMPLE 16
[0312] FIG. 18 shows the effects of pre-treatment with naked hMN-14 CEA
Mab given 3 days prior to CPT-11 treatment in a cancer model. In a
reduced tumor burden model utilizing a 5% tumor cell suspension, CPT-11,
hMN-14 alone, and combination therapy of hMN-14+CPT-11 where the hMN-14
was administered 3 days prior to the CPT-11 were compared. Dosages were
as indicated in Example 14. hMN-14 alone increased median survival time
by 21% (p<0.05) under these conditions. CPT 11 alone increased
survival by 76% (p<0.001). By contrast, the combination therapy where
hMN-14 is administered 3 days prior to CPT-11 produced a median survival
time increase of an additional 58% above CPT-11 alone (p<0.001
compared with CPT-11 alone). Pre-treatment with hMN-14 significantly
prolongs survival of animals with low tumor burden in a metastatic model
of human colonic cancer.
EXAMPLE 17
[0313] FIG. 19 shows a comparison of various administration schedules of
naked hMN-14 CEA MAb and CPT-11 in a human colon cancer model. Giving
hMN-14 3 days before CPT-11 is the most effective. Dosages were as
indicated Example 14. When the order is reversed (CPT-11 is given 3 days
before hMN-14) or when both are given together at the same time, median
survival time of 70 days was an increase over the untreated control group
(35 days) but was still significantly less than the median survival time
of 105 days with the hMN-14 pre-treatment 3 days before CPT-11.
EXAMPLE 18
[0314] FIG. 20 shows the effects of GM-CSF pre-treatment on naked hMN-14
CEA Mab therapy in a human colon cancer model. GM-CSF was administered at
a dose of 1 .mu.g/mouse/day on days-4, -3, -2, and -1. Tumor cells were
implanted at day 0 along with hMN-14 treatments. Other dosages were as
indicated Example 14. The GM-CSF pre-treatment resulted in a
statistically significant increase in median survival time (p<0.002)
over either GM-CSF alone or hMN-14 alone.
[0315] Although the foregoing refers to particular preferred embodiments,
it will be understood that the present invention is not so limited. It
will occur to those of ordinary skill in the art that various
modifications may be made to the disclosed embodiments and that such
modifications are intended to be within the scope of the present
invention.
[0316] All of the publications and patent applications and patents cited
in this specification are herein incorporated in their entirety by
reference.
Sequence CWU
1
1
271357DNAMus sp.CDS(1)..(357) 1gag gtg aag ctt ctc gag tct gga ggt ggc ctg
gtg cag tct gga gga 48Glu Val Lys Leu Leu Glu Ser Gly Gly Gly Leu
Val Gln Ser Gly Gly1 5 10
15tcc ctg aaa ctc tcc tgt gca gcc tca gga ttc gat ttt act aca tat
96Ser Leu Lys Leu Ser Cys Ala Ala Ser Gly Phe Asp Phe Thr Thr Tyr
20 25 30tgg atg agt tgg gtc cgg cag
gct cca ggg aaa ggc cta gaa tgg att 144Trp Met Ser Trp Val Arg Gln
Ala Pro Gly Lys Gly Leu Glu Trp Ile 35 40
45gga gaa att cat cca gat agc agt acg att aac tat gcg ccg tct
cta 192Gly Glu Ile His Pro Asp Ser Ser Thr Ile Asn Tyr Ala Pro Ser
Leu 50 55 60aag gat aaa ttc atc gtc
tcc aga gac aac gcc aaa aat acg ctg tac 240Lys Asp Lys Phe Ile Val
Ser Arg Asp Asn Ala Lys Asn Thr Leu Tyr65 70
75 80ctg caa atg agc aaa gtg aga tct gag gac aca
gcc ctt tat tac tgt 288Leu Gln Met Ser Lys Val Arg Ser Glu Asp Thr
Ala Leu Tyr Tyr Cys 85 90
95gca agc ctt tac ttc ggc ttc ccc tgg ttt gct tat tgg ggc caa ggg
336Ala Ser Leu Tyr Phe Gly Phe Pro Trp Phe Ala Tyr Trp Gly Gln Gly
100 105 110act ccg gtc act gtc tct
gca 357Thr Pro Val Thr Val Ser
Ala 1152119PRTMus sp. 2Glu Val Lys Leu Leu Glu Ser Gly Gly Gly Leu
Val Gln Ser Gly Gly1 5 10
15Ser Leu Lys Leu Ser Cys Ala Ala Ser Gly Phe Asp Phe Thr Thr Tyr
20 25 30Trp Met Ser Trp Val Arg Gln
Ala Pro Gly Lys Gly Leu Glu Trp Ile 35 40
45Gly Glu Ile His Pro Asp Ser Ser Thr Ile Asn Tyr Ala Pro Ser
Leu 50 55 60Lys Asp Lys Phe Ile Val
Ser Arg Asp Asn Ala Lys Asn Thr Leu Tyr65 70
75 80Leu Gln Met Ser Lys Val Arg Ser Glu Asp Thr
Ala Leu Tyr Tyr Cys 85 90
95Ala Ser Leu Tyr Phe Gly Phe Pro Trp Phe Ala Tyr Trp Gly Gln Gly
100 105 110Thr Pro Val Thr Val Ser
Ala 1153318DNAMus sp.CDS(1)..(318) 3gaa att cag ctg acc cag tct
cac aaa atg atg tcc aca tca gtg gga 48Glu Ile Gln Leu Thr Gln Ser
His Lys Met Met Ser Thr Ser Val Gly1 5 10
15gac agg gtc agc atc acc tgc aag gcc agt cag gat gtg
ggt act tct 96Asp Arg Val Ser Ile Thr Cys Lys Ala Ser Gln Asp Val
Gly Thr Ser 20 25 30gta gcc
tgg tat caa cag aga cca gga caa tct cct aaa cta ctg att 144Val Ala
Trp Tyr Gln Gln Arg Pro Gly Gln Ser Pro Lys Leu Leu Ile 35
40 45tac tgg aca tcc acc cgg cac act gga gtc
cct gat cgc ttc aca ggc 192Tyr Trp Thr Ser Thr Arg His Thr Gly Val
Pro Asp Arg Phe Thr Gly 50 55 60agt
gtg tct ggg aca gat ttc act ctc acc att acc aat gtg cag tct 240Ser
Val Ser Gly Thr Asp Phe Thr Leu Thr Ile Thr Asn Val Gln Ser65
70 75 80gaa gac ttg gca gat tat
ttc tgt cag caa tat agc ctc tat cgg tcg 288Glu Asp Leu Ala Asp Tyr
Phe Cys Gln Gln Tyr Ser Leu Tyr Arg Ser 85
90 95ttc ggt gga ggc acc aaa ctg gag atc aaa
318Phe Gly Gly Gly Thr Lys Leu Glu Ile Lys
100 1054106PRTMus sp. 4Glu Ile Gln Leu Thr Gln Ser His
Lys Met Met Ser Thr Ser Val Gly1 5 10
15Asp Arg Val Ser Ile Thr Cys Lys Ala Ser Gln Asp Val Gly
Thr Ser 20 25 30Val Ala Trp
Tyr Gln Gln Arg Pro Gly Gln Ser Pro Lys Leu Leu Ile 35
40 45Tyr Trp Thr Ser Thr Arg His Thr Gly Val Pro
Asp Arg Phe Thr Gly 50 55 60Ser Val
Ser Gly Thr Asp Phe Thr Leu Thr Ile Thr Asn Val Gln Ser65
70 75 80Glu Asp Leu Ala Asp Tyr Phe
Cys Gln Gln Tyr Ser Leu Tyr Arg Ser 85 90
95Phe Gly Gly Gly Thr Lys Leu Glu Ile Lys 100
1055117PRTHomo sapiens 5Gln Val Gln Leu Gln Glu Ser Gly
Pro Gly Leu Val Arg Pro Ser Gln1 5 10
15Thr Leu Ser Leu Thr Cys Thr Val Ser Gly Ser Thr Phe Ser
Asn Asp 20 25 30Tyr Tyr Thr
Trp Val Arg Gln Pro Pro Gly Arg Gly Leu Glu Trp Ile 35
40 45Gly Tyr Val Phe Tyr His Gly Thr Ser Asp Asp
Thr Thr Pro Leu Arg 50 55 60Ser Arg
Val Thr Met Leu Val Asp Thr Ser Lys Asn Gln Phe Ser Leu65
70 75 80Arg Leu Ser Ser Val Thr Ala
Ala Asp Thr Ala Val Tyr Tyr Cys Ala 85 90
95Arg Asn Leu Ile Ala Gly Cys Ile Asp Val Trp Gly Gln
Gly Thr Thr 100 105 110Val Thr
Val Ser Ser 1156107PRTHomo sapiens 6Asp Ile Gln Leu Thr Gln Ser
Pro Ser Ser Leu Ser Ala Ser Val Gly1 5 10
15Asp Arg Val Thr Ile Thr Cys Gln Ala Ser Gln Asp Ile
Ile Lys Tyr 20 25 30Leu Asn
Trp Tyr Gln Gln Lys Pro Gly Lys Ala Pro Lys Leu Leu Ile 35
40 45Tyr Glu Ala Ser Asn Leu Gln Ala Gly Val
Pro Ser Arg Phe Ser Gly 50 55 60Ser
Gly Ser Gly Thr Asp Phe Thr Phe Thr Ile Ser Ser Leu Gln Pro65
70 75 80Glu Asp Ile Ala Thr Tyr
Tyr Cys Gln Gln Tyr Gln Ser Leu Pro Tyr 85
90 95Thr Phe Gly Gln Gly Thr Lys Val Glu Ile Lys
100 1057126PRTHomo sapiens 7Glu Val Gln Leu Val Glu
Ser Gly Gly Gly Val Val Gln Pro Gly Arg1 5
10 15Ser Leu Arg Leu Ser Cys Ser Ser Ser Gly Phe Ile
Phe Ser Ser Tyr 20 25 30Ala
Met Tyr Trp Val Arg Gln Ala Pro Gly Lys Gly Leu Glu Trp Val 35
40 45Ala Ile Ile Trp Asp Asp Gly Ser Asp
Gln His Tyr Ala Asp Ser Val 50 55
60Lys Gly Arg Phe Thr Ile Ser Arg Asp Asn Ser Lys Asn Thr Leu Phe65
70 75 80Leu Gln Met Asp Ser
Leu Arg Pro Glu Asp Thr Gly Val Tyr Phe Cys 85
90 95Ala Arg Asp Gly Gly His Gly Phe Cys Ser Ser
Ala Ser Cys Phe Gly 100 105
110Pro Asp Tyr Trp Gly Gln Gly Thr Pro Val Thr Val Ser Ser 115
120 1258119PRTHomo sapiens 8Gln Val Gln Leu
Gln Glu Ser Gly Pro Gly Leu Val Arg Pro Ser Gln1 5
10 15Thr Leu Ser Leu Thr Cys Thr Ala Ser Gly
Phe Asp Phe Thr Thr Tyr 20 25
30Trp Met Ser Trp Val Arg Gln Pro Pro Gly Arg Gly Leu Glu Trp Ile
35 40 45Gly Glu Ile His Pro Asp Ser Ser
Thr Ile Asn Tyr Ala Pro Ser Leu 50 55
60Lys Asp Arg Val Thr Met Leu Arg Asp Thr Ser Lys Asn Gln Phe Ser65
70 75 80Leu Arg Leu Ser Ser
Val Thr Ala Ala Asp Thr Ala Val Tyr Tyr Cys 85
90 95Ala Ser Leu Tyr Phe Gly Phe Pro Trp Phe Ala
Tyr Trp Gly Gln Gly 100 105
110Thr Thr Val Thr Val Ser Ser 1159119PRTHomo sapiens 9Gln Val Gln
Leu Gln Glu Ser Gly Pro Gly Leu Val Arg Pro Ser Gln1 5
10 15Thr Leu Ser Leu Thr Cys Thr Ala Ser
Gly Phe Asp Phe Thr Thr Tyr 20 25
30Trp Met Ser Trp Val Arg Gln Pro Pro Gly Arg Gly Leu Glu Trp Ile
35 40 45Gly Glu Ile His Pro Asp Ser
Ser Thr Ile Asn Tyr Ala Pro Ser Leu 50 55
60Lys Asp Arg Val Thr Met Leu Arg Asp Thr Ser Lys Asn Thr Leu Tyr65
70 75 80Leu Arg Leu Ser
Ser Val Thr Ala Ala Asp Thr Ala Val Tyr Tyr Cys 85
90 95Ala Ser Leu Tyr Phe Gly Phe Pro Trp Phe
Ala Tyr Trp Gly Gln Gly 100 105
110Thr Thr Val Thr Val Ser Ser 11510119PRTHomo sapiens 10Gln Val
Gln Leu Gln Glu Ser Gly Pro Gly Leu Val Arg Pro Ser Gln1 5
10 15Thr Leu Ser Leu Thr Cys Thr Ala
Ser Gly Phe Asp Phe Thr Thr Tyr 20 25
30Trp Met Ser Trp Val Arg Gln Pro Pro Gly Arg Gly Leu Glu Trp
Ile 35 40 45Gly Glu Ile His Pro
Asp Ser Ser Thr Ile Asn Tyr Ala Pro Ser Leu 50 55
60Lys Asp Arg Val Thr Met Leu Arg Asp Thr Ser Lys Asn Gln
Phe Ser65 70 75 80Leu
Arg Leu Ser Lys Val Arg Ser Glu Asp Thr Ala Val Tyr Tyr Cys
85 90 95Ala Ser Leu Tyr Phe Gly Phe
Pro Trp Phe Ala Tyr Trp Gly Gln Gly 100 105
110Thr Thr Val Thr Val Ser Ser 11511119PRTHomo
sapiens 11Gln Val Gln Leu Gln Glu Ser Gly Pro Gly Leu Val Arg Pro Ser
Gln1 5 10 15Thr Leu Ser
Leu Thr Cys Thr Ala Ser Gly Phe Asp Phe Thr Thr Tyr 20
25 30Trp Met Ser Trp Val Arg Gln Pro Pro Gly
Arg Gly Leu Glu Trp Ile 35 40
45Gly Glu Ile His Pro Asp Ser Ser Thr Ile Asn Tyr Ala Pro Ser Leu 50
55 60Lys Asp Lys Phe Ile Val Ser Arg Asp
Thr Ser Lys Asn Gln Phe Ser65 70 75
80Leu Arg Leu Ser Ser Val Thr Ala Ala Asp Thr Ala Val Tyr
Tyr Cys 85 90 95Ala Ser
Leu Tyr Phe Gly Phe Pro Trp Phe Ala Tyr Trp Gly Gln Gly 100
105 110Thr Thr Val Thr Val Ser Ser
11512119PRTHomo sapiens 12Glu Val Gln Leu Val Glu Ser Gly Gly Gly Val Val
Gln Pro Gly Arg1 5 10
15Ser Leu Arg Leu Ser Cys Ser Ser Ser Gly Phe Asp Phe Thr Thr Tyr
20 25 30Trp Met Ser Trp Val Arg Gln
Ala Pro Gly Lys Gly Leu Glu Trp Val 35 40
45Ala Glu Ile His Pro Asp Ser Ser Thr Ile Asn Tyr Ala Pro Ser
Leu 50 55 60Lys Asp Arg Phe Thr Ile
Ser Arg Asp Asn Ser Lys Asn Thr Leu Phe65 70
75 80Leu Gln Met Asp Ser Leu Arg Pro Glu Asp Thr
Gly Val Tyr Phe Cys 85 90
95Ala Ser Leu Tyr Phe Gly Phe Pro Trp Phe Ala Tyr Trp Gly Gln Gly
100 105 110Thr Pro Val Thr Val Ser
Ser 11513119PRTHomo sapiens 13Glu Val Gln Leu Val Glu Ser Gly Gly
Gly Val Val Gln Pro Gly Arg1 5 10
15Ser Leu Arg Leu Ser Cys Ser Ala Ser Gly Phe Asp Phe Thr Thr
Tyr 20 25 30Trp Met Ser Trp
Val Arg Gln Ala Pro Gly Lys Gly Leu Glu Trp Ile 35
40 45Gly Glu Ile His Pro Asp Ser Ser Thr Ile Asn Tyr
Ala Pro Ser Leu 50 55 60Lys Asp Arg
Phe Thr Ile Ser Arg Asp Asn Ser Lys Asn Thr Leu Phe65 70
75 80Leu Gln Met Asp Ser Leu Arg Pro
Glu Asp Thr Gly Val Tyr Phe Cys 85 90
95Ala Ser Leu Tyr Phe Gly Phe Pro Trp Phe Ala Tyr Trp Gly
Gln Gly 100 105 110Thr Pro Val
Thr Val Ser Ser 11514119PRTHomo sapiens 14Glu Val Gln Leu Val Glu
Ser Gly Gly Gly Val Val Gln Pro Gly Arg1 5
10 15Ser Leu Arg Leu Ser Cys Ser Ala Ser Gly Phe Asp
Phe Thr Thr Tyr 20 25 30Trp
Met Ser Trp Val Arg Gln Ala Pro Gly Lys Gly Leu Glu Trp Ile 35
40 45Gly Glu Ile His Pro Asp Ser Ser Thr
Ile Asn Tyr Ala Pro Ser Leu 50 55
60Lys Asp Arg Phe Thr Ile Ser Arg Asp Asn Ala Lys Asn Thr Leu Phe65
70 75 80Leu Gln Met Asp Ser
Leu Arg Pro Glu Asp Thr Gly Val Tyr Phe Cys 85
90 95Ala Ser Leu Tyr Phe Gly Phe Pro Trp Phe Ala
Tyr Trp Gly Gln Gly 100 105
110Thr Pro Val Thr Val Ser Ser 11515119PRTHomo sapiens 15Glu Val
Gln Leu Val Glu Ser Gly Gly Gly Val Val Gln Pro Gly Arg1 5
10 15Ser Leu Arg Leu Ser Cys Ser Ala
Ser Gly Phe Asp Phe Thr Thr Tyr 20 25
30Trp Met Ser Trp Val Arg Gln Ala Pro Gly Lys Gly Leu Glu Trp
Ile 35 40 45Gly Glu Ile His Pro
Asp Ser Ser Thr Ile Asn Tyr Ala Pro Ser Leu 50 55
60Lys Asp Arg Phe Thr Ile Ser Arg Asp Asn Ala Lys Asn Thr
Leu Tyr65 70 75 80Leu
Gln Met Asp Ser Leu Arg Pro Glu Asp Thr Gly Val Tyr Phe Cys
85 90 95Ala Ser Leu Tyr Phe Gly Phe
Pro Trp Phe Ala Tyr Trp Gly Gln Gly 100 105
110Thr Pro Val Thr Val Ser Ser 11516357DNAHomo
sapiensCDS(1)..(357) 16gag gtc caa ctg gtg gag agc ggt gga ggt gtt gtg
caa cct ggc cgg 48Glu Val Gln Leu Val Glu Ser Gly Gly Gly Val Val
Gln Pro Gly Arg1 5 10
15tcc ctg cgc ctg tcc tgc tcc gca tct ggc ttc gat ttc acc aca tat
96Ser Leu Arg Leu Ser Cys Ser Ala Ser Gly Phe Asp Phe Thr Thr Tyr
20 25 30tgg atg agt tgg gtg aga cag
gca cct gga aaa ggt ctt gag tgg att 144Trp Met Ser Trp Val Arg Gln
Ala Pro Gly Lys Gly Leu Glu Trp Ile 35 40
45gga gaa att cat cca gat agc agt acg att aac tat gcg ccg tct
cta 192Gly Glu Ile His Pro Asp Ser Ser Thr Ile Asn Tyr Ala Pro Ser
Leu 50 55 60aag gat aga ttt aca ata
tcg cga gac aac gcc aag aac aca ttg ttc 240Lys Asp Arg Phe Thr Ile
Ser Arg Asp Asn Ala Lys Asn Thr Leu Phe65 70
75 80ctg caa atg gac agc ctg aga ccc gaa gac acc
ggg gtc tat ttt tgt 288Leu Gln Met Asp Ser Leu Arg Pro Glu Asp Thr
Gly Val Tyr Phe Cys 85 90
95gca agc ctt tac ttc ggc ttc ccc tgg ttt gct tat tgg ggc caa ggg
336Ala Ser Leu Tyr Phe Gly Phe Pro Trp Phe Ala Tyr Trp Gly Gln Gly
100 105 110acc ccg gtc acc gtc tcc
tca 357Thr Pro Val Thr Val Ser
Ser 11517119PRTHomo sapiens 17Glu Val Gln Leu Val Glu Ser Gly Gly
Gly Val Val Gln Pro Gly Arg1 5 10
15Ser Leu Arg Leu Ser Cys Ser Ala Ser Gly Phe Asp Phe Thr Thr
Tyr 20 25 30Trp Met Ser Trp
Val Arg Gln Ala Pro Gly Lys Gly Leu Glu Trp Ile 35
40 45Gly Glu Ile His Pro Asp Ser Ser Thr Ile Asn Tyr
Ala Pro Ser Leu 50 55 60Lys Asp Arg
Phe Thr Ile Ser Arg Asp Asn Ala Lys Asn Thr Leu Phe65 70
75 80Leu Gln Met Asp Ser Leu Arg Pro
Glu Asp Thr Gly Val Tyr Phe Cys 85 90
95Ala Ser Leu Tyr Phe Gly Phe Pro Trp Phe Ala Tyr Trp Gly
Gln Gly 100 105 110Thr Pro Val
Thr Val Ser Ser 11518318DNAHomo sapiensCDS(1)..(318) 18gac atc cag
ctg acc cag agc cca agc agc ctg agc gcc agc gtg ggt 48Asp Ile Gln
Leu Thr Gln Ser Pro Ser Ser Leu Ser Ala Ser Val Gly1 5
10 15gac aga gtg acc atc acc tgt aag gcc
agt cag gat gtg ggt act tct 96Asp Arg Val Thr Ile Thr Cys Lys Ala
Ser Gln Asp Val Gly Thr Ser 20 25
30gta gct tgg tac cag cag aag cca ggt aag gct cca aag ctg ctg atc
144Val Ala Trp Tyr Gln Gln Lys Pro Gly Lys Ala Pro Lys Leu Leu Ile
35 40 45tac tgg aca tcc acc cgg cac
act ggt gtg cca agc aga ttc agc ggt 192Tyr Trp Thr Ser Thr Arg His
Thr Gly Val Pro Ser Arg Phe Ser Gly 50 55
60agc ggt agc ggt acc gac ttc acc ttc acc atc agc agc ctc cag cca
240Ser Gly Ser Gly Thr Asp Phe Thr Phe Thr Ile Ser Ser Leu Gln Pro65
70 75 80gag gac atc gcc
acc tac tac tgc cag caa tat agc ctc tat cgg tcg 288Glu Asp Ile Ala
Thr Tyr Tyr Cys Gln Gln Tyr Ser Leu Tyr Arg Ser 85
90 95ttc ggc caa ggg acc aag gtg gaa atc aaa
318Phe Gly Gln Gly Thr Lys Val Glu Ile Lys
100 10519106PRTHomo sapiens 19Asp Ile Gln Leu Thr
Gln Ser Pro Ser Ser Leu Ser Ala Ser Val Gly1 5
10 15Asp Arg Val Thr Ile Thr Cys Lys Ala Ser Gln
Asp Val Gly Thr Ser 20 25
30Val Ala Trp Tyr Gln Gln Lys Pro Gly Lys Ala Pro Lys Leu Leu Ile
35 40 45Tyr Trp Thr Ser Thr Arg His Thr
Gly Val Pro Ser Arg Phe Ser Gly 50 55
60Ser Gly Ser Gly Thr Asp Phe Thr Phe Thr Ile Ser Ser Leu Gln Pro65
70 75 80Glu Asp Ile Ala Thr
Tyr Tyr Cys Gln Gln Tyr Ser Leu Tyr Arg Ser 85
90 95Phe Gly Gln Gly Thr Lys Val Glu Ile Lys
100 1052011PRTMus sp. 20Lys Ala Ser Gln Asp Val Gly
Thr Ser Val Ala1 5 10217PRTMus sp. 21Trp
Thr Ser Thr Arg His Thr1 5228PRTMus sp. 22Gln Gln Tyr Ser
Leu Tyr Arg Ser1 5235PRTMus sp. 23Thr Tyr Trp Met Ser1
52417PRTMus sp. 24Glu Ile His Pro Asp Ser Ser Thr Ile Asn Tyr
Ala Pro Ser Leu Lys1 5 10
15Asp2510PRTMus sp. 25Leu Tyr Phe Gly Phe Pro Trp Phe Ala Tyr1
5 1026119PRTHomo sapiens 26Gln Val Gln Leu Gln Glu
Ser Gly Pro Gly Leu Val Arg Pro Ser Gln1 5
10 15Thr Leu Ser Leu Thr Cys Thr Val Ser Gly Ser Thr
Phe Ser Thr Tyr 20 25 30Trp
Met Ser Trp Val Arg Gln Pro Pro Gly Arg Gly Leu Glu Trp Ile 35
40 45Gly Glu Ile His Pro Asp Ser Ser Thr
Ile Asn Tyr Ala Pro Ser Leu 50 55
60Lys Asp Arg Val Thr Met Leu Val Asp Thr Ser Lys Asn Gln Phe Ser65
70 75 80Leu Arg Leu Ser Ser
Val Thr Ala Ala Asp Thr Ala Val Tyr Tyr Cys 85
90 95Ala Arg Leu Tyr Phe Gly Phe Pro Trp Phe Ala
Tyr Trp Gly Gln Gly 100 105
110Thr Thr Val Thr Val Ser Ser 11527119PRTHomo sapiens 27Glu Val
Gln Leu Val Glu Ser Gly Gly Gly Val Val Gln Pro Gly Arg1 5
10 15Ser Leu Arg Leu Ser Cys Ser Ser
Ser Gly Phe Ile Phe Ser Thr Tyr 20 25
30Trp Met Ser Trp Val Arg Gln Ala Pro Gly Lys Gly Leu Glu Trp
Val 35 40 45Ala Glu Ile His Pro
Asp Ser Ser Thr Ile Asn Tyr Ala Pro Ser Leu 50 55
60Lys Asp Arg Phe Thr Ile Ser Arg Asp Asn Ser Lys Asn Thr
Leu Phe65 70 75 80Leu
Gln Met Asp Ser Leu Arg Pro Glu Asp Thr Gly Val Tyr Phe Cys
85 90 95Ala Arg Leu Tyr Phe Gly Phe
Pro Trp Phe Ala Tyr Trp Gly Gln Gly 100 105
110Thr Pro Val Thr Val Ser Ser 115
* * * * *