PRIMARY OBJECTIVES:~I. To estimate the complete remission rate (CRR) by the International Myeloma Working Group (IMWG) criteria within 9 months post salvage auto-transplant with daratumumab maintenance therapy starting approximately 3 months post salvage auto-transplant in patients with relapsed myeloma.~SECONDARY OBJECTIVES:~I. To evaluate progression-free survival (PFS).~EXPLORATORY OBJECTIVES:~I. To discover the impact of daratumumab on graft function and immune reconstitution.~OUTLINE:~Beginning 60-180 days after transplant, patients daratumumab and hyaluronidase-fihj subcutaneously (SC) on days 1, 8, 15, and 22 of cycles 1 and 2, on days 1 and 15 of cycles 3-6, and then on day 1 of subsequent cycles. Patients also receive pomalidomide orally (PO) once daily (QD) on days 1-21. Cycles repeat every 28 days for up to 3 years in the absence of disease progression or unacceptable toxicity.~After completion of study treatment, patients are followed up at 30 and 90 days, then every 12 weeks thereafter.
This phase II trial studies whether daratumumab and hyaluronidase-fihj and pomalidomide work in treating patients with multiple myeloma that has come back (relapsed) after stem cell transplant. Daratumumab and hyaluronidase-fihj is a monoclonal antibody that may interfere with the ability of cancer cells to grow and spread. Chemotherapy drugs, such as pomalidomide, work in different ways to stop the growth of cancer cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Giving daratumumab and hyaluronidase-fihj with pomalidomide may help control the disease in patients with relapsed multiple myeloma.