Neoadjuvant Pembrolizumab in Combination With Gemcitabine Therapy in Cis-eligible/Ineligible UC Subjects

In this dose-finding cohort, pembrolizumab (MK-3475) will be administered (cisplatin-eligible patients only) at starting dose 200mg IV every 21 days for 4 cycles to determine RP2D. Once MTD is established in phase Ib, pembrolizumab will be administered on phase II cohorts I and II at RP2D every 21 days for 5 cycles.

For cisplatin-eligible patients on phase Ib and phase II cohort 1, gemcitabine 1000mg/m2 IV, D1 and D8 every 21 days for 4 cycles. For cisplatin-ineligible patients on phase II cohort II, gemcitabine 1000mg/m2 will be administered D1, D8 and D15 every 28 days for 3 cycles.

For cisplatin-eligible patients, cisplatin 70mg/m2 IV will be administered D1 every 21 days for 4 cycles.

Following completion of treatment, subjects will then have surgery to remove their primary tumor within 2-7 weeks after their last dose of neoadjuvant therapy.