Daratumumab Versus Lenalidomide As Maintenance Therapy in Newly Diagnosed Multiple Myeloma – Interim Efficacy Results of a Randomized Clinical Trial
Results: At data cutoff in June 2024, 86 pts have been enrolled of whom 74 were evaluable (37 in len arm, 37 in dara arm) with a median follow up of 19.3 months. Of the 74 pts, median age was 70 with 44.6% ≥65yrs, 56.7% male; 70.3% White, 20.3% Black, 1.3% Asian and 8.1% other races. High risk cytogenetics were present in 32.4% in dara arm and 24.3% in len arm. In the len arm, 51.3% received quadruplets, 46% triplets and 1 pt received infusional chemotherapy. In the dara arm, 51.4% received quadruplets while 48.6% pts received triplet regimens. Dara during induction was received by 64.8% in dara arm and 56.7% in the len arm. ASCT was done in 81.1% of the len arm and 75.6% of the dara arm. Best responses to date in the len arm included 48.6% stringent complete response (sCR), 29.7% CR, 18.9% VGPR and 2.7% progression of disease and in the dara arm 70.2% sCR, 18.9% CR and 10.9% VGPR. Among those , MRD negativity was achieved at screening, year 1 and year 2 in len arm (43.2% [16/37], 48.1% [13/27], 64.3% [9/14]) and in dara arm (51.4% [19/37], 59.1% [13/22], 71.4% [10/14]) respectively. Pts on len arm demonstrated 12-month PFS of 89.7% (n=21) and 24-month PFS of 74.4% (n=9) while pts on dara arm 12-month PFS of 93.3% (n=24) and 24month PFS of 83.1% (n=10). Of 17 pts that came off the study prior to end of treatment, 11 were due to disease progression (6 in len arm; 5 in dara arm) and 6 due to other reasons [len arm - neuropathy (n=2), arthralgia (n=1); dara arm - pneumonitis (n=1), osteomyelitis (n=1) and new CML needing treatment (n=1)].
Conclusions: The study enrolled a racially diverse population and early efficacy data suggest similar best response rates and 12- and 24-month PFS between dara and len arms. These data add to ongoing trials utilizing anti-CD38 monoclonal antibodies (mAbs) as part of maintenance strategies (NCT04071457; NCT03617731). Given encouraging efficacy signals, antiCD38mAbs may be considered an effective maintenance strategy, especially in pts with len intolerance. Updated data will be presented at the meeting.