[The efficacy and safety of daratumumab in relapsed and refractory multiple myeloma]

Objective: To investigate the efficacy and safety of daratumumab in relapsed and refractory multiple myeloma (RRMM). Methods: The efficacy and adverse events (AEs) of daratumumab based regimens were retrospectively analyzed in 37 patients with RRMM from Peking University People's Hospital, Beijing Hospital and Fu Xing Hospital affiliated to Capital Medical University in China. The deadline for inclusion was December, 2019. Results: Among the 37 patients, 35 patients were available for response evaluation. The overall response rate (ORR) was 68.6%, which was better in patients receiving 16 mg/kg daratumumab than in those with fixed doses of 800 mg daratumumab [ORR: 78.3%(18/23) vs. 40.0%(4/10)]. The percentage of infusion related reactions of daratumumab was 27.0%(10/37). The most common hematological AEs were lymphocytopenia and thrombocytopenia, with the incidences of grade 3 or more severe 59.5%(22/37) and 43.2%(16/37) respectively. Pulmonary infections(37.8%, 14/37) were the most common non-hematological AEs. One patient with positive hepatitis B surface antigen (HBsAg) and two patients dependent on dialysis were safely treated with daratumumab. Conclusion: Daratumumab is highly effective in relapsed and refractory multiple myeloma. Adverse reactions are mild and well tolerable.