Efficacy and Safety of Daratumumab (DARA) Monotherapy in Patients with Intermediate-Risk or High-Risk Smoldering Multiple Myeloma (SMM): Final Analysis of the Phase 2 Centaurus Study

Introduction: SMM is a precursor disorder to multiple myeloma (MM) (Rajkumar SV, et al. Blood. 2015;125[20]:3069-3075). Current guidelines for SMM recommend active monitoring, with treatment initiation only upon progression to MM. However, therapeutic intervention at the SMM stage may help delay the progression to MM (Lonial S, et al. J Clin Oncol. 2020;38[11]:1126-1137; Mateos MV, et al. ASH 2022. Abstract 118). DARA is a human IgGκ monoclonal antibody targeting CD38 with a direct on-tumor and immunomodulatory mechanism of action. Given the deep and durable responses and favorable safety profile of DARA monotherapy in patients (pts) with relapsed/refractory MM (Usmani SZ, et al. Blood. 2016;128[1]:37-44), we hypothesized that DARA could delay the progression of SMM to MM. In the primary analysis of the phase 2 CENTAURUS study (NCT02316106), after a 15.8-month median follow-up, DARA monotherapy showed activity and was well tolerated in pts with intermediate- or high-risk SMM (Landgren CO, et al. Leukemia. 2020;34[7]:1840-1852). Activity and tolerability of DARA monotherapy were also observed in CENTAURUS after an additional 10 months of median follow-up (Landgren CO, et al. ASH 2018. Abstract 1994). Here, we present the final analysis of the CENTAURUS study, with a median follow-up of 85.2 months (~7 years).