The addition of daratumumab to lenalidomide, bortezomib, and dexamethasone therapy improved responses in Black transplant-eligible patients with newly diagnosed multiple myeloma (MM), according to research presented at the 2020 Society of Hematologic Oncology Annual Meeting.
The randomized, phase II GRIFFIN study randomized patients to receive lenalidomide 25 mg orally, bortezomib 1.3 mg/m2 subcutaneously, and dexamethasone 40 mg with (n=104) or without (n=103) daratumumab 16 mg/kg intravenously. The reported subgroup analysis assessed the efficacy of these regimens in a cohort of 32 Black patients: 14 received daratumumab and 18 did not.
Black patients who received daratumumab were significantly more likely to achieve stringent complete response (71% vs. 33%; P=0.0353) or complete response or better (P=0.0085). Response rates and depth of response improved at all time points for Black patients treated with daratumumab. A higher percentage of Black patients who received daratumumab achieved minimal residual disease negativity at a level of 1×10-5 (36% vs. 17%).
The most common hematologic adverse events (AEs) that occurred more frequently in the daratumumab group included neutropenia, anemia, leukopenia, and thrombocytopenia. The most common non-hematologic AEs that occurred more frequently in the daratumumab group included upper respiratory tract infection, fatigue, constipation, nausea, peripheral edema, vomiting, cough, pyrexia, and insomnia. No AEs resulted in death. A total of 36% of daratumumab-treated patients and 28% of non-daratumumab-treated patients discontinued therapy.
“Improved recruitment of Black patients in clinical trials is needed to understand disease biology and response to therapy among racial groups,” the researchers concluded.