This is a Phase 1b/2 multi-center, open-label study to determine the safety, tolerability, and efficacy of B-701 (vofatamab) plus pembrolizumab in the treatment of subjects with locally advanced or metastatic UCC, who have progressed following platinum-based chemotherapy and who have not received prior immune checkpoint inhibitor or FGFR inhibitor-targeted therapy. The study consists of 2 parts: a Phase 1b lead-in phase enrolling 6 to 18 subjects and a Phase 2 dose expansion phase enrolling up to a total of 74 subjects.
Subjects who discontinue B-701 (vofatamab) may continue on study and receive pembrolizumab alone until disease progression, death, withdrawal of patient consent, or study termination. Subjects who discontinue pembrolizumab may continue on study and receive B-701 (vofatamab) alone until disease progression, death, withdrawal of patient consent, or study termination.