Humanized PAI-1 antibodies
The present application relates to compositions of humanized anti-PAI-1 antibodies and antigen-binding fragments thereof which convert PAI-1 to its latent form. One aspect relates to antibodies having one or more modifications in at least one amino acid residue of at least one of the framework regions of the variable heavy chain, the variable light chain or both. Another aspect relates to antibodies which bind and neutralize PAI-1 by converting PAI-1 to its latent form or increasing proteolytic cleavage. Another aspect relates to the use of humanized antibodies which inhibit or neutralize PAI-1 for the detection, diagnosis or treatment of a disease or condition associated with PAI-1 or a combination thereof.
1. A method of treating a fibrotic condition in a subject, comprising administering to the subject an antibody or antigen-binding fragment thereof that binds plasminogen activator inhibitor-1 (PAI-1), wherein the fibrotic condition is a liver fibrosis, and wherein the antibody or antigen-binding fragment thereof comprises a heavy chain variable region and a light chain variable region,
wherein said heavy chain variable region comprises:
(i) a CDR1 of SEQ ID NO: 93, a CDR2 of SEQ ID NO: 94, and a CDR3 of SEQ ID NO: 95;
(ii) a heavy chain FR1 having the amino acid sequence of SEQ ID NO: 78 or the amino acid sequence of SEQ ID NO: 78 except for one or more substitutions selected from the group consisting of:
(a) a substitution of tyrosine (Y) by phenylalanine (F) at position 27;
(b) a substitution of threonine (T) by asparagine (N) at position 28;
(c) a substitution of phenylalanine (F) by isoleucine (I) at position 29; and
(d) a substitution of threonine (T) by lysine (K) at position 30 utilizing the Kabat numbering system;
(iii) a heavy chain FR2 having the amino acid sequence of SEQ ID NO: 84 or the amino acid sequence of SEQ ID NO: 84 except for one or more substitutions selected from the group consisting of:
(a) a substitution of glutamine (Q) by lysine (K) at position 38, and
(b) a substitution of methionine (M) by isoleucine (I) at position 48 utilizing the Kabat numbering system;
(iv) a heavy chain FR3 having the amino acid sequence of SEQ ID NO: 88 or the amino acid sequence of SEQ ID NO: 88 except for one or more substitutions selected from the group consisting of:
(a) a substitution of arginine (R) by lysine (K) at position 66;
(b) a substitution of valine (V) by alanine (A) at position 67;
(c) a substitution of alanine (A) by threonine (T) at position 93; and
(d) a substitution of threonine (T) by arginine (R) at position 94 utilizing the Kabat numbering system; and
(v) a heavy chain FR4 having the amino acid sequence of SEQ ID NO: 92 or the amino acid sequence of SEQ ID NO: 92 except for one or more conservative substitutions;
and said light chain variable region comprises:
(i) a CDR1 of SEQ ID NO: 96, a CDR2 of SEQ ID NO: 97, and a CDR3 of SEQ ID NO: 98;
(ii) a light chain FR1 having the amino acid sequence of SEQ ID NO: 68 or the amino acid sequence of SEQ ID NO: 68 except for one or more conservative substitutions;
(iii) a light chain FR2 having the amino acid sequence of SEQ ID NO: 69 or the amino acid sequence of SEQ ID NO: 69 except for one or more substitutions selected from the group consisting of:
(a) a substitution of alanine (A) by threonine (T) at position 43; and
(b) a substitution of proline (P) by valine (V) at position 44 utilizing the Kabat numbering system;
(iv) a light chain FR3 having the amino acid sequence of SEQ ID NO: 73 or the amino acid sequence of SEQ ID NO: 73 except for one or more substitutions selected from the group consisting of:
(a) a substitution of phenylalanine (F) by tyrosine (Y) at position 71; and
(b) a substitution of tyrosine (Y) by phenylalanine (F) at position 87 utilizing the Kabat numbering system; and
(v) a light chain FR4 having the amino acid sequence of SEQ ID NO: 77 or the amino acid sequence of SEQ ID NO: 77 except for one or more conservative substitutions.
2. The method of claim 1 , wherein said antibody, or antigen-binding fragment thereof, comprises a heavy chain variable region having an amino acid sequence set forth as SEQ ID NO: 64, 65, 66 or 67; and a light chain variable region having an amino acid sequence set forth as SEQ ID NO: 62 or 63.
3. The method of claim 1 , wherein said liver fibrosis is selected from cirrhosis, hepatitis C viral (HCV) infection, hepatitis B viral (HBV) infection, non-alcoholic steatohepatitis (NASH), Alcoholic liver disease (ALD), Primary sclerosing cholangitis, Autoimmune hepatitis, Hereditary hemochromatosis, and Wilson's disease.
4. The method of claim 1 , wherein said antibody or antigen-binding fragment thereof is labeled with a therapeutic label, a detectable label or both.
5. The method of claim 1 , further comprising administering one or more anti-fibrotic therapeutic regimens.
6. The method of claim 5 , wherein said one or more anti-fibrotic therapeutic regimens is a second anti-PAI-1 antibody or antigen-binding fragment thereof.