COMPOSITION COMPRISING ANTIBODY THAT BINDS TO DOMAIN II OF HER2 AND ACIDIC VARIANTS THEREOF
A composition comprising a main species HER2 antibody that binds to domain II of HER2 and acidic variants thereof is described. Pharmaceutical formulations comprising the composition, and therapeutic uses for the composition are also disclosed.
1 . A composition comprising a main species HER2 antibody that binds to domain II of HER2, and acidic variants thereof wherein the acidic variants include glycated variant, disulfide reduced variant, or non-reducible variant.
2 . The composition of claim 1 wherein the composition comprises glycated variant.
3 . The composition of claim 1 wherein the composition comprises a disulfide reduced variant.
4 . The composition of claim 1 wherein the composition comprises a non-reducible variant.
5 . The composition of claim 1 wherein the acidic variants include glycated variant, deamidated variant, disulfide reduced variant, sialylated variant, and non-reducible variant.
6 . The composition of claim 1 wherein the amount of the acidic variants is less than about 25%.
7 . The composition of claim 1 wherein the main species HER2 antibody and the acidic variants are all intact antibodies.
8 . The composition of claim 1 wherein the main species HER2 antibody comprises variable light and variable heavy amino acid sequences in SEQ ID Nos. 3 and 4, respectively.
9 . The composition of claim 8 wherein the main species HER2 antibody comprises light chain and heavy chain amino acid sequences in SEQ ID Nos 15 and 16, respectively.
10 . The composition of claim 1 comprising an amino-terminal leader extension variant of the main species antibody.
11 . The composition of claim 10 wherein the amino-terminal leader extension comprises VHS−.
12 . The composition of claim 11 wherein the amino-terminal leader extension consists of VHS−.
13 . The composition of claim 1 comprising an amino acid sequence variant of the main species HER2 antibody selected from the group consisting of an antibody comprising a C-terminal lysine residue on one or both heavy chains thereof, and an antibody with one or more oxidized methionine residues.
14 . A pharmaceutical formulation comprising the composition of claim 1 in a pharmaceutically acceptable carrier.
15 . The pharmaceutical formulation of claim 14 which is sterile.
16 . A method of treating HER2 positive cancer in a patient comprising administering a pharmaceutical formulation comprising a main species HER2 antibody that binds to domain II of HER2, and acidic variants thereof wherein the acidic variants include glycated variant, disulfide reduced variant, or non-reducible variant in a pharmaceutically acceptable carrier to the patient in an amount effective to treat the cancer.
17 . The method of claim 16 wherein the cancer is selected from the group consisting of breast cancer, ovarian cancer, lung cancer, and colorectal cancer.
18 . The method of claim 16 wherein the main species antibody and acidic variants have essentially the same pharmacokinetics.
19 . A method of making a pharmaceutical composition comprising: (1) preparing a composition comprising a main species HER2 antibody that binds to domain II of HER2, and acidic variants thereof including glycated variant, disulfide reduced variant, or non-reducible variant, and (2) evaluating the acidic variants in the composition, and confirming that the amount thereof is less than about 25%.
20 . The method of claim 19 wherein step (2) comprises evaluating the acidic variants by a method selected from the group consisting of ion exchange chromatography wherein the composition is treated with sialidase, reduced capillary electrophoresis with sodium dodecyl sulfate (CE-SDS), non-reduced CE-SDS, boronate chromatography, and peptide mapping.