	US 12,077,576 B2
	*VHH polypeptides that bind to Clostridium difficile* toxin b and methods of use thereof**
Charles B. Shoemaker, Medford, MA (US)
Assigned to Trustees of Tufts College, Medford, MA (US)
Appl. No. 18/013,195
Filed by Trustees of Tufts College, Medford, MA (US)
PCT Filed Jun. 30, 2021, PCT No. PCT/US2021/039798 § 371(c)(1), (2) Date Dec. 27, 2022, PCT Pub. No. WO2022/006219, PCT Pub. Date Jan. 6, 2022.
Claims priority of provisional application 63/047,436, filed on Jul. 2, 2020.
Prior Publication US 2023/0192825 A1, Jun. 22, 2023
Int. Cl. C07K 16/12 (2006.01); A61P 31/04 (2006.01); C07K 14/47 (2006.01); A61K 39/00 (2006.01)

CPC C07K 16/1282 (2013.01) [A61P 31/04 (2018.01); C07K 14/47 (2013.01); A61K 2039/505 (2013.01)]

17 Claims

1. A polypeptide that specifically binds to Clostridium difficile (C. difficile) toxin B (TcdB), or a TcdB-binding portion thereof, wherein the polypeptide comprises three complementarity determining regions (CDRs), CDR1, CDR2 and CDR3, and four VHH framework regions (FRs), FR1, FR2, FR3 and FR4, with the general structure FR1-CDR1-FR2-CDR2-FR3-CDR3-FR4,

wherein CDR1 comprises amino acid sequence GSVYTF (SEQ ID NO: 25); CDR2 comprises amino acid sequence SGGTITK (SEQ ID NO: 26); and CDR3 comprises amino acid sequence NAGDTIAQAMGTRRFPFDR (SEQ ID NO: 27);

wherein CDR1 comprises amino acid sequence GTSFPRNY (SEQ ID NO: 28); CDR2 comprises amino acid sequence SHDGNVE (SEQ ID NO: 29); and CDR3 comprises amino acid sequence KLVTLRRDEY (SEQ ID NO: 30);

wherein CDR1 comprises amino acid sequence RFSLINYA (SEQ ID NO: 31); CDR2 comprises amino acid sequence TSGGATY (SEQ ID NO: 32); and CDR3 comprises amino acid sequence AAGPYSRTLVSRWKVGDGMEY (SEQ ID NO: 33);

wherein CDR1 comprises amino acid sequence GFTSNSYY (SEQ ID NO: 34); CDR2 comprises amino acid sequence SSSGGSPN (SEQ ID NO: 35); and CDR3 comprises amino acid sequence AASKFPLTTMASNRYHY (SEQ ID NO: 36);

wherein CDR1 comprises amino acid sequence GRGPGINV (SEQ ID NO: 37); CDR2 comprises amino acid sequence QTGGTTN (SEQ ID NO: 38); and CDR3 comprises amino acid sequence YLKKWRDEY (SEQ ID NO: 39);

wherein CDR1 comprises amino acid sequence GSSFSMNV (SEQ ID NO: 40); CDR2 comprises amino acid sequence RSDGITN (SEQ ID NO: 41); and CDR3 comprises amino acid sequence FHGRARTGNNADLGS (SEQ ID NO: 42);

wherein CDR1 comprises amino acid sequence GRLSERIFMIST (SEQ ID NO: 43); CDR2 comprises amino acid sequence SRLGRAN (SEQ ID NO: 44); and CDR3 comprises amino acid sequence NLKPFVDNYR (SEQ ID NO: 45);

wherein CDR1 comprises amino acid sequence GITFSNVA (SEQ ID NO: 46); CDR2 comprises amino acid sequence STGGSSTS (SEQ ID NO: 47); and CDR3 comprises amino acid sequence VKGPKYSATIRRPE (SEQ ID NO: 48);

wherein CDR1 comprises amino acid sequence GFNFSVQI (SEQ ID NO: 49); CDR2 comprises amino acid sequence STGGASKS (SEQ ID NO: 50); and CDR3 comprises amino acid sequence SKGPRTWINSSPR (SEQ ID NO: 51);

wherein CDR1 comprises amino acid sequence GTAFSLDT (SEQ ID NO: 52); CDR2 comprises amino acid sequence SSSGASN (SEQ ID NO: 53); and CDR3 comprises amino acid sequence YRGRVRGVWPLDSGMMY (SEQ ID NO: 54);

wherein CDR1 comprises amino acid sequence GSILSS (SEQ ID NO: 55); CDR2 comprises amino acid sequence SRTGATD (SEQ ID NO: 56); and CDR3 comprises amino acid sequence NAGLGMGDPRRPGPW (SEQ ID NO: 57); or

wherein CDR1 comprises amino acid sequence ERNPGINA (SEQ ID NO: 58); CDR2 comprises amino acid sequence WQTGGSLS (SEQ ID NO: 59); and CDR3 comprises amino acid sequence YLKKWRDQY (SEQ ID NO: 60).