For patients with newly diagnosed multiple myeloma who are ineligible for autologous stem cell transplantation (ASCT), adding daratumumab to lenalidomide and dexamethasone provides better outcomes than standard therapy alone, based on an interim analysis from the phase 3 MAIA trial.
A greater proportion of patients in the daratumumab group had complete responses and were alive without disease progression after a median follow-up of 28 months, reported lead author Thierry Facon, MD, of the University of Lille (France) and colleagues, who also noted that daratumumab was associated with higher rates of grade 3 or 4 pneumonia, neutropenia, and lymphopenia.
“For patients who are ineligible for stem-cell transplantation, multiagent regimens, including alkylating agents, glucocorticoids, immunomodulatory drugs, proteasome inhibitors, and new agents, are the standard of care,” the investigators wrote in the New England Journal of Medicine.
The findings from MAIA add clarity to the efficacy and safety of daratumumab in this setting, building on previous phase 3 myeloma trials in the same area, such as ALCYONE, CASTOR, and POLLUX, the investigators noted.
MAIA was an open-label, international trial involving 737 patients with newly diagnosed multiple myeloma who were ineligible for ASCT. Patients were randomized in a 1:1 ratio to receive either daratumumab, lenalidomide, and dexamethasone (daratumumab group; n = 368) or lenalidomide and dexamethasone alone (control group; n = 369).
On a 28-day cycle, all patients received oral lenalidomide 25 mg on days 1-21 and oral dexamethasone 40 mg on days 1, 8, 15, and 22. Patients in the daratumumab group received intravenous daratumumab dosed at 16 mg/kg once a week for cycles 1 and 2, every 2 weeks for cycles 3-6, and then every 4 weeks thereafter. Treatment was continued until unacceptable toxic effects or disease progression occurred.
The primary end point was progression-free survival (PFS). Various secondary end points were also evaluated, including time to progression, complete responses, overall survival, and others.
Among the 737 randomized patients, 729 ultimately underwent treatment. The median patient age was 73 years.
Generally, efficacy measures favored adding daratumumab. After a median follow-up of 28.0 months, disease progression or death had occurred in 26.4% of patients in the daratumumab group, compared with 38.8% in the control group.
The median PFS was not reached in the daratumumab group, compared with 31.9 months in the control group. There was a 44% lower risk of disease progression or death among patients who received daratumumab, compared with the control group (hazard ratio, 0.56, P less than .001).
This PFS trend was consistent across most subgroups, including those for sex, age, and race, with the exception of patients with baseline hepatic impairment.
Additional efficacy measures added weight to the apparent benefit of adding daratumumab. For instance, more patients in the daratumumab group achieved a complete response or better (47.6% vs. 24.9%) and were negative for minimum residual disease (24.2% vs. 7.3%).
In terms of safety, more patients in the daratumumab group than the control group developed grade 3 or higher neutropenia (50% vs. 35.3%), lymphopenia (15.1% vs. 10.7%), infections (32.1% vs. 23.3%) or pneumonia (13.7% vs. 7.9%).
In contrast, grade 3 or 4 anemia was less common in the daratumumab group than the control group (11.8% vs. 19.7%). Overall, the rate of serious adverse events was similar for both groups (approximately 63%), as was the rate of adverse events resulting in death (approximately 6%-7%).
“In this trial involving patients with newly diagnosed multiple myeloma who were ineligible for stem-cell transplantation, the addition of daratumumab to lenalidomide and dexamethasone resulted in significantly longer progression-free survival, a higher response rate, an increased depth of response, and a longer duration of response than lenalidomide and dexamethasone alone,” the investigators concluded.
The study was funded by Janssen Research and Development. The investigators reported relationships with Janssen, Celgene, Takeda, Sanofi, and other companies.
SOURCE: Facon T et al. N Engl J Med. 2019;380:2104-15.