Objective Response Rate (Cohort B)

Progressed on Daratumumab + Pomalidomide + Dexamethasone (Cohort B)

Patients with relapsed or refractory multiple myeloma who have progressed on the combination of Dara + Pom + Dex (Cohort B) to be treated with a combination of Dara + Pom + Dex + ATRA (All-Transretinoic Acid) Daratumumab: During 28-day treatment cycles, patients will receive Dara 16 mg/kg intravenously (IV) at their current dose upon enrollment onto the study depending on their cycle. They will receive Dara depending on the cycle they are in. If they are on cycles 1-2 then they will receive Dara 16 mg/kg IV on days 1,8,15,22; if they are on cycles 3-6 they will receive Dara 16 mg/kg on days 1 and 15; and if they are on cycle 7 or beyond they will receive Dara 16 mg/kg on day 1. Pomalidomide: Pomalidomide will be administered at the patient's currently tolerated dose (4,3, or 2 mg po daily) on days 1-21 All-trans retinoic acid: ATRA will be administered in a divided dose of twice daily as an oral formulation at 45mg/m2/day for 3 days. The first administration of ATRA will be given in the morning, two days before the scheduled Dara infusion. The last administration of ATRA will be given in the evening of the day that Dara was administered Dexamethasone: Dexamethasone will be administered at 40 mg once weekly on days 1,8,15 for patients 75 years old and younger and at 20 mg once weekly on days 1,8,15 for patients older than 75.

Analysis denominator · Participants