ALK2 antibodies and methods of use thereof
The invention features ALK2 antibodies and antigen binding fragments thereof (e.g., ALK2 binding fragments). The invention also features pharmaceutical compositions and methods of using the ALK2 antibodies or antigen binding fragments thereof to treat bone disease or damage, low red blood cell levels (e.g., anemia or blood loss), heterotopic ossification (e.g., heterotopic ossification resulting from fibrodysplasia ossificans progressiva), Sjogren's syndrome (e.g., dry eye associated with Sjogren's syndrome), multiple osteochondroma, diffuse intrinsic pontine glioma, posterior capsule opacification, or cardiac hypertrophy and/or cardiac fibrosis.
1. An isolated ALK2 antibody, or an antigen binding fragment thereof, comprising:
(a) a light chain complementarity determining region (CDR) 1 comprising the amino acid sequence SGSSSNIGSNYVS (SEQ ID NO: 1); a light chain CDR2 comprising the amino acid sequence VLIYKNNHRPS (SEQ ID NO: 24); a light chain CDR3 comprising the amino acid sequence ASWDHSDRFYV (SEQ ID NO: 4); a heavy chain CDR1 comprising the amino acid sequence GGTFSSYGVS (SEQ ID NO: 31); a heavy chain CDR2 comprising the amino acid sequence WMGGIIPHFGIANYAQKFQG (SEQ ID NO: 36); and a heavy chain CDR3 comprising the amino acid sequence EIGSLDI (SEQ ID NO: 13);
(b) a light chain CDR1 comprising the amino acid sequence SGDSIPSFFAS (SEQ ID NO: 18); a light chain CDR2 comprising the amino acid sequence LVIYRDSNRPS (SEQ ID NO: 25); a light chain CDR3 comprising the amino acid sequence YVTAPWKSIW (SEQ ID NO: 5); a heavy chain CDR1 comprising the amino acid sequence GFTFSSHAMS (SEQ ID NO: 32); a heavy chain CDR2 comprising the amino acid sequence WVGRIKSKADSGTTDYAAPVKG (SEQ ID NO: 37); and a heavy chain CDR3 comprising the amino acid sequence DYGVAFAY (SEQ ID NO: 14);
(c) a light chain CDR1 comprising the amino acid sequence SGDNIGTKYAY (SEQ ID NO: 19); a light chain CDR2 comprising the amino acid sequence LVIYGDSDRPS (SEQ ID NO: 26); a light chain CDR3 comprising the amino acid sequence YSADAQQMKA (SEQ ID NO: 6); a heavy chain CDR1 comprising the amino acid sequence GFTFNSSAMS (SEQ ID NO: 33); a heavy chain CDR2 comprising the amino acid sequence WVGRIKSKRDGYTTDYAAPVKG (SEQ ID NO: 38); and a heavy chain CDR3 comprising the amino acid sequence DYGGLKFDY (SEQ ID NO: 15);
(d) a light chain CDR1 comprising the amino acid sequence SGDNLRKYSAH (SEQ ID NO: 20); a light chain CDR2 comprising the amino acid sequence LVIYYDNKRPS (SEQ ID NO: 27); a light chain CDR3 comprising the amino acid sequence QVYASVHRM (SEQ ID NO: 7); a heavy chain CDR1 comprising the amino acid sequence GGTFSSYAIH (SEQ ID NO: 34); a heavy chain CDR2 comprising the amino acid sequence WMGRIIPDFGTANYAQKFQG (SEQ ID NO: 39); and a heavy chain CDR3 comprising the amino acid sequence GPTQAIHYFAY (SEQ ID NO: 16); or
(e) a light chain CDR1 comprising the amino acid sequence SGDSLGSKSVH (SEQ ID NO: 21); a light chain CDR2 comprising the amino acid sequence LVIYRDSKRPS (SEQ ID NO: 28); a light chain CDR3 comprising the amino acid sequence QTYDWSHFGW (SEQ ID NO: 8); a heavy chain CDR1 comprising the amino acid sequence GFTFSSAAMH (SEQ ID NO: 35); a heavy chain CDR2 comprising the amino acid sequence WVSVISSDGGSTYYADSVKG (SEQ ID NO: 12); and a heavy chain CDR3 comprising the amino acid sequence AGFILGSLGVAWMDV (SEQ ID NO: 17).
2. The isolated ALK2 antibody, or antigen binding fragment thereof, of claim 1 , wherein the light chain CDR1 comprises the amino acid sequence SGSSSNIGSNYVS (SEQ ID NO: 1); the light chain CDR2 comprises the amino acid sequence VLIYKNNHRPS (SEQ ID NO: 24); the light chain CDR3 comprises the amino acid sequence ASWDHSDRFYV (SEQ ID NO: 4); the heavy chain CDR1 comprises the amino acid sequence GGTFSSYGVS (SEQ ID NO: 31); the heavy chain CDR2 comprises the amino acid sequence WMGGIIPHFGIANYAQKFQG (SEQ ID NO: 36); and the heavy chain CDR3 comprises the amino acid sequence EIGSLDI (SEQ ID NO: 13).
3. The isolated ALK2 antibody, or antigen binding fragment thereof, of claim 1 , wherein the light chain CDR1 comprises the amino acid sequence SGDSIPSFFAS (SEQ ID NO: 18); the light chain CDR2 comprises the amino acid sequence LVIYRDSNRPS (SEQ ID NO: 25); the light chain CDR3 comprises the amino acid sequence YVTAPWKSIW (SEQ ID NO: 5); the heavy chain CDR1 comprises the amino acid sequence GFTFSSHAMS (SEQ ID NO: 32); the heavy chain CDR2 comprises the amino acid sequence WVGRIKSKADSGTTDYAAPVKG (SEQ ID NO: 37); and the heavy chain CDR3 comprises the amino acid sequence DYGVAFAY (SEQ ID NO: 14).
4. The isolated ALK2 antibody, or antigen binding fragment thereof, of claim 1 , wherein the light chain CDR1 comprises the amino acid sequence SGDNIGTKYAY (SEQ ID NO: 19); the light chain CDR2 comprises the amino acid sequence LVIYGDSDRPS (SEQ ID NO: 26); the light chain CDR3 comprises the amino acid sequence YSADAQQMKA (SEQ ID NO: 6); the heavy chain CDR1 comprises the amino acid sequence GFTFNSSAMS (SEQ ID NO: 33); the heavy chain CDR2 comprises the amino acid sequence WVGRIKSKRDGYTTDYAAPVKG (SEQ ID NO: 38); and the heavy chain CDR3 comprises the amino acid sequence DYGGLKFDY (SEQ ID NO: 15).
5. The isolated ALK2 antibody, or antigen binding fragment thereof, of claim 1 , wherein the light chain CDR1 comprises the amino acid sequence SGDNLRKYSAH (SEQ ID NO: 20); the light chain CDR2 comprises the amino acid sequence LVIYYDNKRPS (SEQ ID NO: 27); the light chain CDR3 comprises the amino acid sequence QVYASVHRM (SEQ ID NO: 7); the heavy chain CDR1 comprises the amino acid sequence GGTFSSYAIH (SEQ ID NO: 34); the heavy chain CDR2 comprises the amino acid sequence WMGRIIPDFGTANYAQKFQG (SEQ ID NO: 39); and the heavy chain CDR3 comprises the amino acid sequence GPTQAIHYFAY (SEQ ID NO: 16).
6. The isolated ALK2 antibody, or antigen binding fragment thereof, of claim 1 , wherein the light chain CDR1 comprises the amino acid sequence SGDSLGSKSVH (SEQ ID NO: 21); the light chain CDR2 comprises the amino acid sequence LVIYRDSKRPS (SEQ ID NO: 28); the light chain CDR3 comprises the amino acid sequence QTYDWSHFGW (SEQ ID NO: 8); and the heavy chain CDR1 comprises the amino acid sequence GFTFSSAAMH (SEQ ID NO: 35); the heavy chain CDR2 comprises the amino acid sequence WVSVISSDGGSTYYADSVKG (SEQ ID NO: 12); and the heavy chain CDR3 comprises the amino acid sequence AGFILGSLGVAWMDV (SEQ ID NO: 17).
7. The isolated ALK2 antibody of claim 1 , wherein the antibody, apart from the light chain CDR1, CDR2, and CDR3 and the heavy chain CDR1, CDR2, and CDR3, has at least 90% sequence identity to amino acids 1 to 331 of the sequence of SEQ ID NO:67, amino acids 1 to 332 of the sequence of SEQ ID NO:68, amino acids 1 to 333 of the sequence of SEQ ID NO:69, amino acids 1 to 332 of the sequence of SEQ ID NO:70, or amino acids 1 to 337 of the sequence of SEQ ID NO:71.
8. The isolated ALK2 antibody of claim 1 , wherein the antibody comprises amino acids 1 to 433 of the sequence of SEQ ID NO:67, amino acids 1 to 434 of the sequence of SEQ ID NO:68, amino acids 1 to 435 of the sequence of SEQ ID NO:69, amino acids 1 to 434 of the sequence of SEQ ID NO: 70, or amino acids 1 to 439 of the sequence of SEQ ID NO:71.
9. A nucleic acid molecule comprising a nucleotide sequence encoding the ALK2 antibody or antigen binding fragment thereof of claim 1 .
10. An expression vector comprising the nucleic acid molecule of claim 9 .
11. A cell comprising the expression vector of claim 10 .
12. A pharmaceutical composition comprising the ALK2 antibody or antigen binding fragment thereof of claim 1 and one or more pharmaceutically acceptable carriers or excipients.
13. The isolated ALK2 antibody of claim 1 , wherein the antibody comprises amino acids 1 to 112 and amino acids 216 to 331 of the sequence of SEQ ID NO:67, amino acids 1 to 110 and amino acids 214 to 332 of the sequence of SEQ ID NO:68, amino acids 1 to 110 and amino acids 214 to 333 of the sequence of SEQ ID NO: 69, amino acids 1 to 109 and amino acids 213 to 332 of the sequence of SEQ ID NO:70, or amino acids 1 to 110 and amino acids 214 to 337 of the sequence of SEQ ID NO:71.