# US 11,440,949 B2 · TGF-beta superfamily type I and type II receptor heteromultimers and uses thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,440,949 B2 - Document ID: US11440949B2 - Status: Granted - Kind: B2 - Application number: 16/340,040 - Filed: 2017-10-05 - Published: 2021-05-20 - Granted: 2022-09-13 - Earliest claimed: 2016-10-05 - Assignees: Acceleron Pharma Inc. - Applicants: Acceleron Pharma Inc. - Inventors: Ravindra Kumar; Asya Grinberg; Dianne S. Sako; Roselyne Castonguay - Web page: https://patentgrep.com/patent/US11440949B2 ## CPC - A61P 7/00: Drugs for disorders of the blood or the extracellular fluid - C07K 14/71: for growth factors; for growth regulators - A61P 7/06: Antianaemics - A61K 38/00: Medicinal preparations containing peptides (peptides containing beta-lactam rings A61K31/00; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, A61K31/00; ergot alkaloids of the cyclic peptide type A61K31/48; containing macromolecular compounds having statistically distributed amino acid units A61K31/74; medicinal preparations containing antigens or antibodies A61K39/00; medicinal preparations characterised by the non-active ingredients, e.g. peptides as drug carriers, A61K47/00) - C07K 2317/52: Constant or Fc region; Isotype - C07K 2319/30: Non-immunoglobulin-derived peptide or protein having an immunoglobulin constant or Fc region, or a fragment thereof, attached thereto - A61P: SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS - C07K: PEPTIDES (peptides in foodstuffs A23; obtaining protein compositions for foodstuffs, working-up proteins for foodstuffs A23J; preparations for medicinal purposes A61K; peptides containing beta-lactam rings C07D; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, C07D; ergot alkaloids of the cyclic peptide type C07D519/02; macromolecular compounds having statistically distributed amino acid units in their molecules, i.e. when the preparation does not provide for a specific; but for a random sequence of the amino acid units, homopolyamides and block copolyamides derived from amino acids C08G69/00; macromolecular products derived from proteins C08H1/00; preparation of glue or gelatine C09H; single cell proteins, enzymes C12N; genetic engineering processes for obtaining peptides C12N15/00; compositions for measuring or testing processes involving enzymes C12Q; investigation or analysis of biological material G01N33/00) - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) ## Abstract In certain aspects, the disclosure provides soluble heteromeric polypeptide complexes comprising an extracellular domain of a type I serine/threonine kinase receptor of the TGF-beta family and an extracellular domain of a type II serine/threonine kinase receptor of the TGF-beta family. In some embodiments, the disclosure provides soluble polypeptide complexes comprising an extracellular domain of a type II receptor selected from: ActRIIA, ActRIIB, TGFBRII, BMPRII, and MISRII. In some embodiments, the disclosure provides soluble polypeptide complexes comprising an extracellular domain of a type I receptor selected from: ALK1, ALK2, ALK3, ALK4, ALK5, ALK.6, and ALK7. Optionally the soluble complex is a heterodimer. In certain aspects, such soluble polypeptide complexes may be used to regulate (promote or inhibit) growth of tissues or cells including, for example, muscle, bone, cartilage, fat, neural tissue, tumors, cancerous cells, and/or cells of hematopoietic lineages, including red blood cells. In certain aspects, such soluble polypeptide complexes are can be used to improve muscle formation, bone formation, hematopoiesis, metabolic parameters, and disorders associated with these tissues, cellular networks, and endocrine systems. ## Claims ### Claim 1 A recombinant heteromultimer comprising an ALK3-Fc fusion protein and an ActRIIB-Fc fusion protein, (a) wherein the ALK3-Fc fusion protein comprises: (1) an ALK3 domain comprising an amino acid sequence that is at least 90% identical to amino acids 61-130 of SEQ ID NO: 22, and (2) an Fc domain that is an IgG1 Fc domain, and wherein the IgG1 domain comprises a cysteine substitution at the position corresponding to S132 of SEQ ID NO: 3100 (S132C) and a tryptophan substitution at the position corresponding to T144 of SEQ ID NO: 3100 (T144W), wherein the amino acid substitutions alter the isoelectric point (pI) of the ALK3-Fc fusion protein; and (b) wherein the ActRIIB-Fc fusion protein comprises: (1) an ActRIIB domain comprising an amino acid sequence that is at least 90% identical to amino acids 29-109 of SEQ ID NO: 1, and (2) an Fc domain that is an IgG1 Fc domain, and wherein the IgG1 Fc domain comprises one or more amino acid modifications that alter the pI of the ActRIIB-Fc fusion protein, and wherein the heteromultimer binds to BMP2 and/or BMP4. ### Claim 2 (depends on 1) The heteromultimer of claim 1, wherein the ActRIIB-Fc fusion protein comprises one or more amino acid modifications that decrease the pI of the ActRIIB-Fc fusion protein. ### Claim 3 (depends on 2) The heteromultimer of claim 2, wherein the ActRIIB-Fc fusion protein comprises one or more neutral or positively charged amino acid substitutions with one or more negatively charged amino acids. ### Claim 4 (depends on 1) The heteromultimer of claim 1, wherein the ActRIIB-Fc fusion protein IgG1 Fc domain comprises a cysteine substitution at the position corresponding to Y127 of SEQ ID NO: 3100 (Y127C), a serine substitution at the position corresponding to T144 of SEQ ID NO: 3100 (T144S), an alanine substitution at the position corresponding to L146 of SEQ ID NO: 3100 (L146A), and a valine substitution at the position corresponding to Y185 of SEQ ID NO: 3100 (Y185V). ### Claim 5 A recombinant heteromultimer comprising an ALK3-Fc fusion protein and an ActRIIB-Fc fusion protein, (a) wherein the ALK3-Fc fusion protein comprises: (1) an amino acid sequence that is at least 90% identical to amino acid 61-130 of SEQ ID NO: 22, and (2) an Fc domain that is an IgG1 Fc domain, and wherein the IgG1 Fc domain comprises one or more amino acid modifications that alter the pI of the ALK3-Fc fusion protein; and (b) wherein the ActRIIB-Fc fusion protein comprises: (1) an ActRIIB domain comprising an amino acid sequence that is at least 90% identical to amino acids 29-109 of SEQ ID NO: 1, and (2) an Fc domain that is an IgG1 Fc domain, and wherein the IgG1 Fc domain comprises a cysteine substitution at the position corresponding to S132 of SEQ ID NO: 3100 (S132C) and a tryptophan substitution at the position corresponding to T144 of SEQ ID NO: 3100 (T144, and wherein the heteromultimer binds to BMP2 and/or BMP4. ### Claim 6 (depends on 5) The heteromultimer of claim 5, wherein the ALK3-Fc fusion protein IgG1 Fc domain comprises a cysteine substitution at the position corresponding to Y127 of SEQ ID NO: 3100 (Y127C), a serine substitution at the position corresponding to T144 of SEQ ID NO: 3100 (T144S), an alanine substitution at the position corresponding to L146 of SEQ ID NO: 3100 (L146A), and a valine substitution at the position corresponding to Y185 of SEQ ID NO: 3100 (Y185V). ### Claim 7 (depends on 1, 5) The heteromultimer of claim 1 or claim 5, wherein the ALK3-Fc fusion protein further comprises a linker domain positioned between the ALK3 domain and the Fc domain; and wherein the ActRIIB-Fc fusion protein further comprises a linker domain positioned between the ActRIIB domain and the Fc domain. ### Claim 8 (depends on 7) The heteromultimer of claim 7, wherein each linker domain is independently selected from: TGGG (SEQ ID NO: 62), TGGGG (SEQ ID NO: 60), SGGGG (SEQ ID NO: 61), GGGGS, GGG (SEQ ID NO: 58), GGGG (SEQ ID NO: 59), and SGGG (SEQ ID NO: 18). ### Claim 9 (depends on 1, 5) The heteromultimer of claim 1 or claim 5, wherein the heteromultimer is a heterodimer. ### Claim 10 (depends on 1, 5) The heteromultimer of claim 1 or claim 5, wherein the ALK3-Fc fusion protein and the ActRIIB-Fc fusion protein have at least a 0.7 difference in pI. ### Claim 11 (depends on 1, 5) A pharmaceutical preparation comprising the heteromultimer of claim 1 or claim 5, and a pharmaceutically acceptable carrier. ### Claim 12 (depends on 1, 5) The heteromultimer of claim 1 or claim 5, wherein the ALK3-Fc fusion protein comprises an ALK3 domain comprising an amino acid sequence that is at least 95% or 98% identical to amino acids 61-130 of SEQ ID NO: 22. ### Claim 13 (depends on 12) The heteromultimer of claim 12, wherein the ALK3-Fc fusion protein comprises an ALK3 domain comprising an amino acid sequence of any one of SEQ ID NOs: 22, 23, 115, 117, 407, and 408. ### Claim 14 (depends on 1, 5) The heteromultimer of claim 1 or claim 5, wherein the ActRIIB-Fc fusion protein comprises an ActRIIB domain comprising an amino acid sequence that is at least 95% or 98% identical to amino acids 20-134 of SEQ ID NO: 1. ### Claim 15 (depends on 14) The heteromultimer of claim 14, wherein the ActRIIB-Fc fusion protein comprises an ActRIIB domain comprising an amino acid sequence of any one of SEQ ID NOs: 1, 2, 3, 4, 5, 6, 100, 102, 401, and 402.