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

To investigate the efficacy and safety of daratumumab in relapsed and refractory multiple myeloma (RRMM) . The clinical characteristics, adverse reactions, efficacy, and prognosis of 46 patients with RRMM treated with daratumumab in Shanghai Changzheng Hospital from September 2017 to March 2020 were retrospectively analyzed. All patients were treated with daratumumab-based regimen: 8 in the Dd group, 35 in the DRd group, and 3 in the DVd group. With a median follow-up of 9.6 months, the overall response rate (ORR) was 75% [complete remission (CR) rate 18.2% ] among the 44 patients available for evaluation. The ORRs of patients resistant to bortezomib, lenalidomide, and both were 70.6% , 69.2% , and 63.6% , respectively. The CR rates of patients resistant to bortezomib, lenalidomide, and both were 17.6% , 11.5% , and 13.6% , respectively. No significant difference was observed in ORR and CR rates among the three groups. The ORRs of the DRd, DVd, and Dd groups were 85.3% , 66.7% , and 28.6% , respectively (=0.007) . The median PFS of 46 patients was 8.9 months, the median OS was not reached, and the 1-year OS rate was 74% . The median PFS and OS in the DRd group were longer than those in the Dd group (PFS: 14.4 months 2.0 months; OS: not reached 5.2 months) . After treatment with daratumumab, neutropenia is the most common hematological adverse reaction above grade 3. Non-hematological adverse reactions are mainly infusion-related adverse reactions and infections. Prognostic analysis showed that patients with extramedullary invasion had shorter PFS and OS compard with patients without extramedullary invasion (PFS: 5.7 14.4 months, =0.033; OS: 6.3 months not reached, =0.029) . The OS of patients with an ECOG score of 3-4 was significantly shorter than patients with an ECOG score of 1-2 (5.9 months not reached, =0.004) . Daratumumab-based regimens have good efficacy and safety in the treatment of RRMM.