Efficacy and safety of daratumumab in intermediate/high-risk smoldering multiple myeloma: final analysis of CENTAURUS

• Daratumumab continued to demonstrate single-agent clinical activity in patients with intermediate- or high-risk smoldering myeloma.

• No new safety concerns were observed after extended follow-up of ∼7 years, highlighting the tolerability of daratumumab.

Early intervention in smoldering multiple myeloma (SMM) may delay progression to MM. Here, we present the final analysis of the phase 2 CENTAURUS study. In total, 123 patients with intermediate/high-risk SMM were randomized to IV daratumumab 16 mg/kg after a long-intense (n = 41), intermediate (n = 41), or short-intense (n = 41) dosing schedule. At a combined median follow-up of 85.2 months, in the long-intense, intermediate, and short-intense arms complete response or better rates were 4.9%, 9.8%, and 0%; overall response rates were 58.5%, 53.7%, and 37.5%; progressive disease/death rates were 0.096, 0.102, and 0.109 (P < .0001 for all arms); and median progression-free survival was not reached, 84.4, and 74.1 months, respectively. Median overall survival was not reached in any arm. Thirty-six patients in the long-intense or intermediate arms continued daratumumab in an optional extension phase after completing 20 cycles of per-protocol treatment. The median duration of study treatment was 44.0 (range, 1.0-91.6), 35.2 (range, 1.9-90.6), and 1.6 (range, 0.1-1.9) months in the long-intense, intermediate, and short-intense arms, respectively. No new safety signals were observed. With extended follow-up (median, ∼7 years), these data highlight the tolerability of daratumumab and support ongoing trials investigating daratumumab as an early intervention for SMM. This trial was registered at www.ClinicalTrials.gov as #NCT02316106.