ANTI-STEAP2 ANTIBODIES, CONJUGATES ANTIBODY MEDICINES AND BISSPECIFIC ANTIGEN BINDING MOLECULES THAT BIND STEAP2 AND CD3, AND THEIR APPLICATION

摘要

A protein known as six-membranous epithelial antigen of the prostate 2 (STEAP2) is expressed high in prostate cancer and is associated with the expression of other genes associated with prostate cancer. The present invention provides novel, full-length human IgG antibodies that bind to human STEAP2 (monospecific antibodies). The invention also provides novel bispecific antibodies (bsAbs) that bind to both STEAP2 and CD3 and activate T cells through the CD3 complex in the presence of tumors expressing STEAP2. In accordance with some embodiments, the invention provides bispecific antigen binding molecules comprising a first antigen binding domain that specifically binds human and monkey CD3, and a second antigen binding molecule that specifically binds human STEAP2. In certain embodiments, said bispecific antigen binding molecules of the invention are capable of inhibiting the growth of tumors expressing STEAP2. These bispecific antigen binding molecules of the invention are useful for treating diseases and disorders of the prostate gland in which an enhanced or induced STEAP2-directed immune response is desired and / or therapeutically useful. For example, the bispecific antibodies of the invention are useful for treating prostate cancer, including castration-resistant prostate cancer. The invention also includes anti-STEAP2 antibody drug conjugates that inhibit tumor growth in vivo.