(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)
`E
`(19) World Intellectual Property
`Organization
`International Bureau
`
`L
`_;
`
`(10) International Publication Number
`WO 2016/106302 A1
`
`(43) International Publication Date
`30 June 2016 (30.06.2016)
`
`W I P O I P C T
`
`(51)
`
`(21)
`
`(22)
`
`(25)
`(26)
`(30)
`
`(71)
`
`(72)
`
`International Patent Classification:
`C07K 16/28 (2006.01)
`International Application Number:
`PCT/US2015/067332
`
`International Filing Date:
`22 December 2015 (22.12.2015)
`English
`English
`
`Filing Language:
`Publication Language:
`Priority Data:
`US
`62/096,267
`23 December 2014 (23.12.2014)
`Applicant: BRISTOL-MYERS SQUIBB COMPANY
`[US/US]; Route 206 and Province Line Road, Princeton,
`New Jersey 08543 (US).
`Inventors: MAURER, Mark F.; c/o Bristol Myers Squibb
`Company, 1201 Eastlake Avenue E., Seattle, Washington
`98102 (US). CHEN, Tseng-Hui Timothy; c/o Bristol-My-
`ers Squibb Company, 700 Bay Road, Redwood City, Cali-
`fornia 94063 (US). DEVAUX, Brigitte; c/o Bristol Myers
`Squibb Company, 700 Bay Road, Redwood City, Califor-
`nia 94063 (US). SRINIVASAN, Mohan; c/o Bristol-My-
`ers Squibb Company, 700 Bay Road, Redwood City, Cali-
`fornia 94063 (US). JULIEN, Susan H.; c/o Bristol-Myers
`Squibb Company, 1201 Eastlake Avenue E., Seattle,
`Washington 98102 (US). SHEPPARD, Paul O.; c/o Bris-
`tol-Myers Squibb Company, 1201 Eastlake Avenue E.,
`Seattle, Washington 98102 (US). ARDOUREL, Daniel
`
`(74)
`
`(81)
`
`(84)
`
`F.; c/o Bristol-Myers Squibb Company, 1201 Eastlake Av-
`enue
`E.,
`Seattle, Washington
`98102
`(US).
`CHAKRABORTY, Indrani; c/o Bristol-Myers Squibb
`Company, 700 Bay Road, Redwood City, California 94063
`(US).
`Agents: BELLOMY, Gregory R. et a1.; Bristol-Myers
`Squibb Company, Route 206 & Province Line Road, Prin-
`ceton, New Jersey 08543 (US).
`Designated States (unless otherwise indicated, for every
`kind of national protection available): AE, AG, AL, AM,
`AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY,
`BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DK, DM,
`DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT,
`HN,H R,HU,ID, IL,,,INIRIS, JP, KE, KG,KN,,KP KR,
`KZ,LA , LC, LK, LR LS, LU, LY, MA, MD, ME, MG,
`MK, MN, MW,MX ,,MY MZ, NA, NG, NI, NO, NZ, OM,
`PA, PE, PG, P , PL, PT, QA, RO, RS, RU, RW, SA, SC,
`SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, TN,
`TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW.
`Designated States (unless otherwise indicated, for every
`kind of regional protection available): ARIPO (BW, GH,
`GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, ST, SZ,
`TZ, UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU,
`TJ, TM), European (AL, AT, BE, BG, CH, CY, CZ, DE,
`DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU,
`LV, MC, MK, M1", NL, NO, PL, PT, RO, RS, SE, SI, SK,
`SM, TR), OAPI (BF, BJ, CF, CG, CI, CM, GA, GN, GQ,
`GW, KM, ML, MR, NE, SN, TD, TG).
`
`[Continued on next page]
`
`(54) Title: ANTIBODIES TO TIGIT
`
`1 600
`
`A
`
`.3
`;
`E 1000
`V
`0
`f
`i l—
`
`500
`
`-.-
`+
`+
`—v—
`
`" '
`
`+
`
`mlgG
`TIGIT G23
`TIGIT G1 D265A
`PD—1 G1 D265A
`PD—1 G1 D265A + TIGIT G2a
`PD—1 G1 D265A + TIGIT G1 D265A
`
`0
`
`o
`
`|
`10
`
`I
`l
`30
`20
`days
`
`40
`
`FIG. 5A
`
`(57) Abstract: The present invention provides antibodies, or antigen binding fragments thereof, that bind to human TIGIT (T cell
`immunoreceptor with Ig and ITIM domains), as well as uses of these antibodies or fragments in therapeutic applications, such as in
`the treatment of cancer or chronic Viral infection. Such method of treatment include combination therapy with inhibitors of other im -
`munomodulatory receptor interactions, such as the PD-l/PD-Ll interaction. The invention further provides polynucleotides encod-
`ing the heavy and/or light chain variable region of the antibodies, expression vectors comprising the polynucleotides encoding the
`heavy and/or light chain variable region of the antibodies, cells comprising the vectors, and methods of making the antibodies or
`fragments by expressing them fi'om the cells.
`
`O W
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`Declarations under Rule 4.17:
`as to applicant’s entitlement to apply for and be granted
`a patent (Rule 4.1 7(ii))
`as to the applicant’s entitlement to claim the priority of
`the earlier application Rule 4.1 7(iii))
`of inventorship Rule 4.1 7(iv))
`
`Published:
`with international search report (Art. 21(3))
`before the expiration of the time limit for amending the
`claims and to be republished in the event of receipt of
`amendments (Rule 48.2(h))
`with sequence listing part of description (Rule 5. 2(a))
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`ANTIBODIES TO TIGIT
`
`BACKGROUND
`
`TIGIT (T cell immunoreceptor with Ig and ITIM domains) is a co-inhibitory
`[0001]
`receptor protein also known as WUCAM, Vstm3 or Vsig9. TIGIT was discovered in
`genomic searches for proteins specifically expressed on T cells, and has an immunoglobulin
`variable domain, a transmembrane domain, and an immunoreceptor tyrosine-based
`inhibitory motif (ITIM), and contains signature sequence elements of the PVR protein
`family. It is known to interact with poliovirus receptor (PVR; CD155) and with nectin2
`(CD112). See e.g. Stengel et al. (2012) Proc. Nat’l Acad. Sci. (USA) 1925399; WO
`2006/ 124667 ; W0 2009/ 126688. Although PVR may interact with the co-activating
`receptor DNAM-l (CD226) to enhance tumor killing, the high affinity TIGIT/PVR
`interaction would inhibit such killing, and may act to prevent killing of normal (self) cells
`that also express PVR. Stanietsky et al. (2009) Proc. Nat’l Acad. Sci. (USA) 106: 17858.
`The dominance of this inhibitory interaction may be important in suppression of anti-self
`immune reactions, but in the tumor context it suppresses tumor eradication. Id.
`[0002]
`TIGIT suppresses T cell activation by promoting the generation of mature
`immunoregulatory dendritic cells. Yu et a]. (2009) Nat. Immunol. 10:48. TIGIT and other
`such co-inhibitory molecules (e. g. CTLA-4, PD-l, Lag3 and BTLA) may play a role in
`evasion of immunosurveillance by tumor cells. Experiments have shown that PVR/CD155
`is over-expressed on melanoma cells (Inozume et a]. (2014) J. Invest. Dermatol. 134:S121 -
`Abstract 693) and various other tumors. It is possible that the TIGIT/PVR interaction can
`shield such tumor cells from immune-mediated eradication by inhibiting anti-tumor
`responses of T and NK cells. Stanietsky et a]. (2009) Proc. Nat ’l Acad. Sci. (USA)
`106: 17858 and Lozano et a]. (2012) J. Immunol. 1883869. Other experiments have
`identified a TIGIT+ subset of regulatory T cells (Tregs) that selectively suppress Th1 and
`Th17 responses (J oller et a]. (2014) Immunity 40:569), suggesting an alternative mechanism
`by which an anti-TIGIT antibody may enhance anti-tumor immune response.
`[0003]
`TIGIT may act to “turn off’ the immune response similarly to other co-
`inhibitory receptors such as CTLA-4, PD-l and BTLA. Id. Antibodies targeting CTLA-4
`(ipilimumab) and PD-l (nivolumab, pembrolizumab) have been approved for the treatment
`of human cancers, validating this therapeutic approach. Antibodies that bind to human
`TIGIT might also find use in treatment of cancers. See e. g. WO 2006/ 124667. In mouse
`
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`models, antibody blockade of both PD-Ll and TIGIT leads to a synergistic enhancement of
`CD8+ T cell mediated tumor rejection. Grogan et al. (2014) J. Immunol. 192(1) Suppl.
`203.15; Johnston et al. (2014) Cancer Cell 26: 1-15. Similar results have been obtained in
`animal models of melanoma. Inozume et al. (2014) J. Invest. Dermatol. 13428121 -
`Abstract 693. Some experiments suggest that TIGIT blockade is effective to enhance anti-
`tumor CD8+ T cell response only in the presence of the co—activating receptor DNAM-
`1/CD226, which competes with TIGIT for binding to PVR/CD155. Johnston et al. (2014)
`Cancer Cell 26:1-15.
`[0004]
`Recent experiments have demonstrated that intratumoral bacteria expressing
`Fap2 protein may inhibit NK cell mediated tumor killing by binding to TIGIT (Gur et al.
`(2015) Immunity 42:344), suggesting that eliminating such bacteria, blocking the interaction
`of TIGIT with Fap2, or blocking the activity of TIGIT generally, may be useful in treatment
`of cancer, e.g. colorectal cancer. Hampton (2015) JAMA 31321305.
`[0005]
`The need exists for improved methods of treating cancer and chronic viral
`infections and medicaments, such as therapeutic monoclonal antibodies, for use in the
`methods. Medicines for use in such improved methods of treatment may comprise
`antibodies or antibody fragments that specifically bind to TIGIT and reverse or partially
`reverse the TIGIT-mediated suppression of anti-tumor or anti-viral immune responses.
`
`SUlVflVIARY OF THE H‘IVENTION
`The present invention provides improved medicines and methods of treatment
`[0006]
`for cancer and chronic viral infection comprising antibodies, or antigen-binding fragments
`thereof, that bind to huTIGIT. Provided herein are isolated antibodies, such as monoclonal
`antibodies, in particular human monoclonal antibodies, that specifically bind huTIGIT and
`have desirable functional properties, such as high affinity specific binding to huTIGIT,
`binding to monkey TIGIT (e.g., cynomolgus TIGIT), the ability to block binding of TIGIT
`to PVR and/or Nectin-2, the ability to block the interaction of TIGIT with DNAM, or any
`combination of these properties.
`[0007]
`The present invention fiirther provides improved methods of treating cancer and
`therapeutic antibodies for use in the methods, including cancers in which TIGIT-mediated
`signaling suppresses anti-tumor immune response, tumors in which TIGIT interaction with
`the co-activating receptor DNAM-l/CD226 suppresses anti-tumor immune response,
`tumors in which TIGIT-expressing regulatory T cells suppress anti-tumor immune response,
`or tumors in which TIGIT otherwise inhibits anti-tumor immune response. The invention
`
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`also provides methods and therapeutic antibodies for use in treating chronic viral infections
`in which TIGIT suppresses anti-viral immune response.
`[0008]
`In another aspect, the present invention relates to antibodies that compete with
`the antibodies having heavy and light chain variable domain sequences disclosed herein for
`binding to huTIGIT, and/or that cross-block the antibodies having heavy and light chain
`variable domain sequences disclosed herein from binding to huTIGIT.
`[0009]
`In certain embodiments, the anti-TIGIT antibodies of the present invention, or
`antigen binding fragments thereof, enhance an anti-tumor immune response, e.g. an antigen-
`specific T cell response. In other embodiments, the anti-TIGIT antibodies of the present
`invention, or antigen binding fragments thereof, block TIGIT mediated inhibitory signaling
`allowing PVR/DNAM co-stimulation of NK cells to increase NK-mediated anti-tumor
`response killing. In yet another embodiment the anti-TIGIT antibodies of the present
`invention, or antigen binding fragments thereof, deplete a population of regulatory T cells
`within a tumor that would otherwise suppress anti-tumor immune response. In yet another
`embodiment, anti-TIGIT antibodies of the present invention formatted as IgGls deplete
`CD8+ exhausted T cells and Tregs, allowing for the influx of fresh, non-exhausted CD8+ T
`cells. In other embodiments the anti-TIGIT antibodies of the present invention, or antigen
`binding fragments thereof, act by one of more of the above-referenced mechanisms since
`the mechanisms are not necessarily mutually exclusive.
`[0010]
`In certain embodiments, the anti-TIGIT antibodies of the present invention, or
`antigen binding fragments thereof, do not bind to activating Fcy receptors (FcyRs), e. g. in
`embodiments relying on enhancing the anti-tumor activity of TIGIT-expressing cells. In
`alternative embodiments, the anti-TIGIT antibodies of the present invention, or antigen
`binding fragments thereof, bind to one or more activating FcyRs, e. g. in embodiments
`relying on killing of TIGIT-expressing cells, such as exhausted CD8+ T cells or Tregs.
`[0011]
`The present invention also provides isolated monoclonal antibodies (15A6),
`or antigen binding fragments thereof, that specifically bind to huTIGIT and comprise heavy
`chain CDRHl, CDRH2, and CDRH3 sequences comprising SEQ ID NOs: 14, 15 and 16,
`respectively, and/or light chain CDRLl, CDRL2, and CDRL3 sequences comprising SEQ
`ID NOs: 17, 18, and 19, respectively.
`[0012]
`The present invention also provides isolated monoclonal antibodies (22G2),
`or antigen binding fragments thereof, that specifically bind to huTIGIT and comprise heavy
`chain CDRHl, CDRH2, and CDRH3 sequences comprising SEQ ID NOs: 20, 21 and 22,
`
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`respectively, and/or light chain CDRLl, CDRL2, and CDRL3 sequences comprising SEQ
`ID NOs: 23, 24, and 25, respectively.
`[0013]
`The present invention firrther provides isolated monoclonal antibodies
`(11G11), or antigen binding fragments thereof, that specifically bind to huTIGIT and
`comprise heavy chain CDRHl, CDRH2, and CDRH3 sequences comprising SEQ ID NOS:
`26, 27 and 28, respectively, and/or light chain CDRLl, CDRL2, and CDRL3 sequences
`comprising SEQ ID NOs: 29, 30, and 31, respectively.
`[0014]
`The present invention yet further provides isolated monoclonal antibodies
`(10D7), or antigen binding fragments thereof, that specifically bind to huTIGIT and
`comprise heavy chain CDRHl, CDRH2, and CDRH3 sequences comprising SEQ ID NOS:
`32, 33 and 34, respectively, and/or light chain CDRLl, CDRL2, and CDRL3 sequences
`comprising SEQ ID NOs: 35, 36, and 37, respectively.
`[0015]
`The present invention also provides isolated monoclonal antibodies, or
`antigen binding fragments thereof, that specifically bind to huTIGIT and comprise the
`variable heavy chain and variable light chain sequence disclosed at SEQ ID NOS: 2 (or 3, 4,
`5) and 6; SEQ ID NOs: 7 (or 8) and 9; SEQ ID NOs: 10 and 11; and SEQ ID NOS: 12 and
`l 3 .
`The present invention provides isolated monoclonal antibodies, or antigen
`[0016]
`binding fragments thereof, that bind to huTIGIT and comprise heavy and light chain
`variable regions, wherein the heavy chain variable region comprises an amino acid
`sequence that is at least 90%, 95% or 99% identical to the amino acid sequence selected
`from the group consisting of SEQ ID NOs: 2, 3, 4, 5, 7, 8, 10 and 12.
`[0017]
`The present invention also provides isolated monoclonal antibodies, or
`antigen binding fragments thereof, that bind to huTIGIT and comprise heavy and light chain
`variable regions, wherein the light chain variable region comprises an amino acid sequence
`that is at least 90%, 95% or 99% identical to the amino acid sequence selected from the
`group consisting of SEQ ID NOs: 6, 9, 11, and 13.
`[0018]
`In certain embodiments, the isolated monoclonal antibodies of the present
`invention, or antigen binding fragments thereof, (a) bind to the same epitope on huTIGIT aS
`15A6, 22G2, llGl 1, and/or 10D7, and/or (b) inhibit binding of 15A6, 22G2, llGl 1, and/or
`10D7 to huTIGIT as measured, e. g., by FACS or ELISA.
`[0019]
`In certain embodiments, the anti-huTIGIT antibodies of the present
`invention, or antigen binding fragments thereof, bind to an epitope comprising or consisting
`of one or more of residues E60, 1109, L65, N70, F107, T117, 168, H76 and N58 (antibody
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`22G2) of huTIGIT (SEQ ID NO: 1), at an epitope comprising or consisting of one or more
`of residues G74, N70, H76, L65, L73, Q56, I68, H111 and P114 (antibody 11G11), or at an
`epitope comprising or consisting of one or more of residues H76, G74, L65, N58, I68,
`Q139, G135, L73, F107, N70, E60, H134, A132 and 1109 (antibody 15A6).
`[0020]
`Alternatively, the anti-huTIGIT antibodies of the present invention, or antigen
`binding fragments thereof, bind at an epitope comprising or consisting of one or more
`sequences selected from the group consisting of NWEQQDQLLAICNADLGWH (SEQ ID
`NO: 38) and FCIYHTYPDGT (SEQ ID NO: 39) (antibody 22G2), or from the group
`consisting of QVNWEQQDQLLAICNADLGWH
`(SEQ ID NO: 40) and HTYP (SEQ ID
`NO: 41) (antibody 11G11), or from the group consisting of
`NWEQQDQLLAICNADLGWH (SEQ ID NO: 38), FCI, and AEHGARF Q (SEQ ID NO:
`43) (antibody 15A6).
`[0021]
`In still further embodiments, the anti-TIGIT antibody of the present invention, or
`antigen binding fragment thereof, binds to a core epitope on huTIGIT (SEQ ID NO: 1)
`comprising or consisting of one or more of residues L65, I68, N70 and H76, and/or at an
`epitope comprising or consisting of LLAICNADLGWH (SEQ ID NO: 44).
`[0022]
`In some embodiments, the anti-huTIGIT antibodies of the present invention, or
`antigen binding fragments thereof, also bind to cynomolgus TIGIT.
`[0023]
`In various embodiments, the anti-TIGIT antibodies, or antigen-binding
`fragments thereof, of the present invention are human IgG1, IgG2, IgG3, or IgG4
`antibodies, or variants thereof. In certain embodiments, including but not limited to
`methods of blocking TIGIT signaling in “exhausted” tumor-specific T cells or blocking
`inhibitory signals on NK cells allowing DNAM-l/PVR—mediated co-stimulation or methods
`of blocking TIGIT interaction with DNAM-l/CD226 to impair DNAM-l
`homodimerization, the anti-TIGIT antibodies, or antigen-binding fragments thereof,
`comprise an effectorless or mostly effectorless Fc. Such Fc regions include, e. g., human
`IgG2 or IgG4, or an effectorless variant of human IgG1 with one or more of the following
`mutations: L234A, L23 5E, G237A, A330S and P331S (EU numbering), including IgG1.1f
`(SEQ ID NO: 48) comprising all five of the listed mutations.
`[0024]
`In alternative embodiments, including but not limited to methods of depleting
`TIGIT+ regulatory T cells, the anti-TIGIT antibodies, or antigen-binding fragments thereof,
`comprise an Fc that preferentially binds to an activating FcyR (FcyRI, FcyRIIa or FcyRIIIa),
`such as a human IgG1, or a sequence variant having enhanced binding to an activating F cyR
`relative to a wild-type IgG1 Fc. In embodiments involving use of IgG1 forms of the anti-
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`TIGIT antibodies of the present invention to drive depletion of Tregs, intratumoral injection
`may be optionally used to localize effects to the tumor microenvironment, minimizing
`potential side effects caused by activity in peripheral tissues.
`[0025]
`In certain embodiments, methionine residues in the CDR regions of the anti-
`TIGIT antibodies of the present invention (e.g. M115 in CDRH3 of 10D7, SEQ ID NO: 34),
`or antigen-binding fragments thereof, are replaced with amino acid residues that do not
`undergo oxidation.
`[0026]
`In certain embodiments, the anti-huTIGIT antibodies that compete for binding,
`cross-block, or bind to the same epitope as 15A6, 22G2, llGll or 10D7, or antigen-binding
`fragments thereof, are human or humanized antibodies.
`[0027]
`In some embodiments, the anti-huTIGIT antibodies of the present invention are
`not, or do not bind to the same epitope as, antibodies described at US. Pat. App. Pub. No.
`2009/0258013, e.g. they do not bind to the same epitope as anti-huTIGIT mAb 10A7 or
`1F4. See also Johnston et al. (2014) Cancer Cell 26: 1; Yu et al. (2009) Nat. Immunol.
`1 0:48.
`In other embodiments, the anti-huTIGIT antibodies comprise variable domains
`[0028]
`derived from the same human V domain germline sequences as the antibodies disclosed
`herein, including heavy chain V domains V4-39, V4-61, or V1-69. In more specific
`embodiments, the anti-huTIGIT antibodies comprise heavy and light chain variable
`domains derived from the same human heavy and light chain V domain germline sequences
`as the antibodies disclosed herein, such as V4-39/VA27 (15A6), V4-61/VL6 (22G2), V4-
`39/VL6 (11G11), and V1-69/VL15 (10D7).
`[0029]
`In various embodiments anti-huTIGIT antibodies of the present invention bind to
`huTIGIT with a KB of less than 10nM, SnM, 2nM, lnM, 300pM or 100pM. In other
`embodiments, the anti-huTIGIT antibodies of the present invention bind to huTIGIT with a
`KD between 2nM and 100pM.
`[0030]
`In other embodiments, the anti-huTIGIT antibodies of the present invention
`consist essentially of, or comprise, some combination of the CDRs of antibodies 15A6,
`22G2, 11G11 and 10D7, such as CDRHl (SEQ ID NOs: 14, 20, 26 and 32); CDRH2 (SEQ
`
`ID NOs: 15, 21, 27 and 33); CDRH3 (SEQ ID NOs: 16, 22, 28 and 34); CDRLl (SEQ ID
`NOs: 17, 23, 29 and 35); CDRL2 (SEQ ID NOs: 18, 24, 30 and 36); and CDRL3 (SEQ ID
`N05: 19, 25, 31 and 37). In other embodiments the antibodies consist essentially of, or
`comprise, the separate specific combinations of the CDR sequences of antibodies 15A6,
`22G2, l l G l l and 10D7.
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`In fiirther embodiments the anti-huTIGIT antibodies of the present invention
`[0031]
`consist essentially of, or comprise, the heavy and/ or light chain variable domains of
`antibodies 15A6 (SEQ ID NOs: 2-5 and 6), 22G2 (SEQ ID NOs: 7-8 and 9), l l G l l (SEQ
`ID NOs: 10 and 11) and 10D7 (SEQ ID NOs: 12 and 13), or sequences sharing at least 80%,
`85%, 90% and 95% sequence identity with these disclosed sequences.
`[0032]
`In yet further embodiments the anti-huTIGIT antibodies of the present invention
`consist essentially of, or comprise, heavy and/or light chains comprising the variable
`domain sequences of antibodies 15A6 (SEQ ID NOs: 2-5 and 6), 22G2 (SEQ ID NOs: 7-8
`and 9), 11G11 (SEQ ID NOs: 10 and 11) and 10D7 (SEQ ID NOs: 12 and 13), or sequences
`sharing at least 80%, 85%, 90% and 95% sequence identity with these disclosed sequences.
`[0033]
`In other embodiments the antigen binding domains of the antibodies of the
`present invention are present in bispecific molecules further comprising an antigen binding
`domain that binds specifically to a different immunomodulatory receptor, including but not
`limited to PD-l, CTLA-4 or LAG3.
`[0034]
`The present invention firrther provides nucleic acids encoding the heavy
`and/or light chain variable regions, of the anti-huTIGIT antibodies of the present invention,
`or antigen binding fragments thereof, expression vectors comprising the nucleic acid
`molecules, cells transformed with the expression vectors, and methods of producing the
`antibodies by expressing the cells transformed with the expression vectors and recovering
`the antibody.
`The present invention also provides immunoconjugates comprising the anti-
`[0035]
`huTIGIT antibodies described herein, linked to an agent, such as a detectable label or
`cytotoxic agent.
`[0036]
`The present invention also provides pharmaceutical compositions comprising
`anti-huTIGIT antibodies of the present invention, or antigen binding fragments thereof, and
`a carrier. Also provided herein are kits comprising the anti-TIGIT antibodies, or antigen
`binding fragments thereof, and instructions for use.
`[0037]
`In another aspect, the present invention provides a method of enhancing an
`antigen-specific T cell response comprising contacting the T cell with an anti-huTIGIT
`antibody of the present invention, or antigen binding fragment thereof, such that an antigen-
`specific T cell response is enhanced, e. g. by reduction of an inhibitory signal that would
`otherwise dampen anti-tumor response. In some embodiments, the antigen-specific T cell is
`a tumor-antigen specific effector T cell, such as a CD8+ T cells, and the enhancement, e. g.
`through blocking of a TIGIT-mediated inhibitory effect, results in increased anti-tumor
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`activity. Anti-huTIGIT antibodies of the present invention, or antigen-binding fragments
`thereof, may also reduce inhibitory signals in NK cells and thus increase their anti-tumor
`activity. Without intending to be limited by theory, anti-huTIGIT antibodies of the present
`invention increase effector T cell or NK cell function by blocking binding of TIGIT to PVR,
`thus reducing or eliminating an inhibitory signal that would otherwise be delivered to the
`cell. Alternatively, or in addition, anti-TIGIT antibodies of the present invention, or antigen
`binding fragments thereof, may inhibit interaction between TIGIT and DNAM-l/CD226
`that would otherwise reduce DNAM-l-mediated immune activation.
`[0038]
`The present invention further provides a method of increasing IL-2 and/or
`lFN-y production in, and/or proliferation of, a T cell comprising contacting the T cell with
`an effective amount of an anti-TIGIT antibody, or antigen binding fragment thereof.
`[0039]
`In another aspect, the present invention provides a method of reducing or
`depleting Tregs in a tumor in a subject in need thereof comprising administering an effective
`amount of an anti-huTIGIT antibody of the present invention, wherein the antibody has
`effector fianction or enhanced effector function, to reduce the number of Tnegs in the tumor.
`[0040]
`The present invention provides a method of enhancing an immune response in a
`subject comprising administering an effective amount of an anti-huTIGIT antibody of the
`present invention, or antigen binding fragment thereof, to the subject such that an immune
`response in the subject is enhanced. In certain embodiments, the subject has a tumor and an
`immune response against the tumor is enhanced. In another embodiment, the subject has a
`viral infection and an anti-viral immune response is enhanced.
`[0041]
`The present invention also provides a method of inhibiting the growth of
`tumors in a subject comprising administering to the subject an anti-huTIGIT antibody of the
`present invention, or antigen binding fragment thereof, such that growth of the tumor is
`inhibited.
`The present invention firrther provides a method of treating cancer, e. g., by
`[0042]
`immunotherapy, comprising administering to a subject in need thereof a therapeutically
`effective amount an anti-huTIGIT antibody of the present invention, or antigen binding
`fragment thereof, e.g. as a pharmaceutical composition, thereby treating the cancer. In
`certain embodiments, the cancer is bladder cancer, breast cancer, uterine/cervical cancer,
`ovarian cancer, prostate cancer, testicular cancer, esophageal cancer, gastrointestinal cancer,
`pancreatic cancer, colorectal cancer, colon cancer, kidney cancer, head and neck cancer,
`lung cancer, stomach cancer, germ cell cancer, bone cancer, liver cancer, thyroid cancer,
`skin cancer, neoplasm of the central nervous system, lymphoma, leukemia, myeloma,
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`sarcoma, and virus-related cancer. In certain embodiments, the cancer is a metastatic
`cancer, refractory cancer, or recurrent cancer.
`[0043]
`In certain embodiments, the methods of modulating immune filnction and
`methods of treatment described herein comprise administering an anti-huTIGIT antibody of
`the present invention in combination with, or as a bispecific reagent with, one or more
`additional therapeutics, for example, an anti-PD-l antibody, an anti-PD-Ll antibody, an
`anti-LAG3 antibody, an anti-GITR antibody, an anti-0X40 antibody, an anti-CD73
`antibody, an anti-CD40 antibody, an anti-CD137 mAb, an anti-CD27 mAb, an anti-CSF-IR
`antibody, and/or an anti-CTLA-4 antibody, a TLR agonist, or a small molecule antagonist
`of IDO or TGFB. In specific embodiments, anti-huTIGIT therapy is combined with anti-
`PD-l and/or anti-PD-Ll therapy, e. g. treatment with an antibody or antigen binding
`fragment thereof that binds to human PD-l or an antibody or antigen binding fragment
`thereof that binds to human PD-Ll.
`[0044]
`In some embodiments, samples from patients, e.g. biopsies, are screened for
`expression of DNAM-l on T cells or NK cells to select patients most likely to respond to
`anti-TIGIT therapy, wherein the presence of DNAM-l on T cells suggests a the patient will
`have a beneficial anti-tumor response upon anti-TIGIT therapy, e.g. treatment with the anti-
`huTIGIT antibody or fragment of the present invention, and the absence of DNAM-l
`identifies patients that are less likely to benefit from anti-TIGIT therapy. In other
`embodiments, samples from patients are screened for expression of PVR and/or Nectin-2 on
`tumor cells or tumor infiltrating myeloid cells to select patients most likely to respond to
`anti-TIGIT therapy, wherein the presence of PVR and/or Nectin-2 suggests a the patient
`will have a beneficial anti-tumor response upon anti-TIGIT therapy, e. g. treatment with the
`anti-huTIGIT antibody or fragment of the present invention, and the absence of PVR and/or
`Nectin-Z/CDl 12 identifies patients that are less likely to benefit from anti-TIGIT therapy.
`In various embodiments, cell-surface expression of TIGIT, DNAM, PVR and/or Nectin-2 is
`by FAC S, IHC or LC-MS. In another aspect, the present invention provides methods of
`treatment of subjects in need thereof involving determination of the cell-surface expression
`of TIGIT, DNAM, PVR and/or Nectin-2 as described herein and administration of anti-
`TIGIT antibodies of the present invention preferentially, or exclusively, to those for whom
`is it most likely to provide therapeutic benefit.
`[0045]
`In one embodiment, the level of soluble PVR and/or soluble Nectin-2 (sPVR,
`sNectin-2) is measured in subjects being considered for treatment with anti-TIGIT
`antibodies of the present invention, and only subjects exhibiting elevated soluble PVR
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`and/or Nectin-2 are treated with the antibodies. In some embodiments, sPVR and/or
`sNectin-2 is detected in serum by ELISA or LC-MS.
`[0046]
`The present invention also provides methods of detecting the presence of
`TIGIT in a sample, on a cell within a sample (e.g. FACS), or in specific locations in a cell
`or tissue (e. g. IHC), or of sorting cells based on the presence or absence of TIGIT on their
`surface (e. g. FACS), comprising contacting the sample with an anti-huTIGIT antibody of
`the present invention, or an antigen binding fragment thereof, under conditions that allow
`for formation of a complex between the antibody, or antigen binding fragment thereof, and
`TIGIT, and detecting the formation of the complex. In some embodiments the anti-TIGIT
`antibody used for detection is conjugated with a detectable label.
`[0047]
`Other features and advantages of the instant disclosure will be apparent from
`the following detailed description and examples, which should not be construed as limiting.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 shows a schematic diagram of “binning” experiments in which various
`[0048]
`anti-huTIGIT antibodies of the present invention are tested, pairwise, for the ability to block
`the binding of other antibodies to huTIGIT. Results show that antibodies fall into a limited
`number of categories, or “bins.” See Example 3.
`[0049]
`FIGs. 2A, 2B, and 2C show yeast display data for binding of huTIGIT sequence
`variants to antibodies 22G2, 11G11, and 15A6, respectively. The residue numbers for each
`amino acid residue in mature huTIGIT are presented along the abscissa. Residue numbers
`are 21 lower than the numbering for SEQ ID NO: 1 because the sequence listing includes
`the signal peptide, which is not included in the figures. As detailed in Example 4, yeast
`displaying sequence variants of huTIGIT were selected based on their inability to bind to
`the respective antibodies (22G2, 11G11, 15A6). Accordingly, positions along the huTIGIT
`sequence that are critical to antibody binding appear at high frequency (lle. as bars/lines
`rising above the ordinate) due to their over-representation in the pool of non-binding yeast
`clones. The frequencies at which variant (non-wild type) residues appear at each residue are
`represented (on a logarithmic scale) on the ordinate, with one bar (line) or each residue.
`Frequency data are normalized to the frequencies at which variant residues appear at each
`position in an unselected library, 1'. e. libraries that had not been subjected to selection based
`on the inability to bind to the anti-huTIGIT antibodies of the present invention. See
`Example 4.
`
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`FIG. 3 shows the effect of anti-TIGIT mAb 22G2 on lysis, expressed as percent
`[0050]