A Study of MK-3475 in Combination With Lenalidomide and Dexamethasone in Participants With Multiple Myeloma (MK-3475-023/KEYNOTE-023)

This study is being done to find the maximum tolerated dose (MTD)/maximum administered dose (MAD) and recommended Phase 2 dose (RP2D), and to evaluate the safety and tolerability of MK-3475 when given in combination with lenalidomide (Len) and dexamethasone (Dex) to participants with multiple myeloma (MM). Preliminary efficacy data will also be assessed. The primary study hypothesis is that this combination is sufficiently well tolerated to permit further clinical investigation.