Safety Analysis of Five Randomized Controlled Studies of Daratumumab in Patients With Multiple Myeloma

Multiple studies have demonstrated the efficacy and safety of daratumumab for relapsed/refractory multiple myeloma (MM) and primary treatment for transplant-eligible and -ineligible patients.

We conducted an integrated safety analysis to characterize the frequency, severity, natural history, and outcomes of adverse events (AEs) with daratumumab versus comparators. Data were pooled from 5 completed phase III randomized controlled studies that had included 1798 daratumumab-treated and 1797 comparator-treated patients with MM as a first line in both transplant-eligible and transplant-ineligible patients and for relapsed/refractory disease. Safety analyses included reporting of AEs using crude and exposure-adjusted incidence rates.

The median follow-up duration was 16.84 months (range, 7.4-28 months) for both daratumumab-treated and comparator-treated patients. Discontinuation for any reason occurred less often with daratumumab (22% vs. 33.9%), although discontinuation because of AEs occurred at similar rates (25% vs. 26%) as did deaths owing to AEs (2.25% vs. 1.84%). When adjusted for exposure, neutropenia, lymphopenia, diarrhea, fatigue, dyspnea, pneumonia, and hypertension were the only common grade 3/4 AEs reported more often with daratumumab than with the comparators. The prevalence of common grade 3/4 AEs with daratumumab were < 7% apart from neutropenia, lymphopenia, and pneumonia (45.9% vs. 32.3%, 13% vs. 7.5%, and 10.6% vs. 7.2%, respectively). Grade 3/4 daratumumab infusion-related reactions happened in 3.8% of patients. The majority of infusion-related reactions occurred after the first infusion.

These results from an integrated analysis support a favorable benefit/risk profile of daratumumab in patients with MM.