Dosing patterns for talquetamab, including dose de-escalation, in a real-world setting

• In the real-world (RW) setting, talquetamab for multiple myeloma is often initiated with inpatient step-up dosing then every-2-week dosing • By 6 months, nearly one-third of RW talquetamab recipients transition to every-4-week or less frequent dosing Talquetamab for relapsed/refractory multiple myeloma is initiated using step-up dosing (SUD) to mitigate cytokine release syndrome (CRS) and neurotoxicity (ICANS); both once-per-week (QW) and every-2-week (Q2W) schedules are approved thereafter. The aim of this study was to better understand early real-world talquetamab usage patterns in the United States (US). We retrospectively analyzed data from two large national US databases, one hospital-based and one outpatient-based. These two databases included patients treated from August 2023 through March 2025 (hospital, n=273) or January 2025 (outpatient, n=257). These databases included patients aged ≥75 years (15.4% and 21.0% of all patients respectively), Black patients (25.6% and 15.2% respectively), and patients treated at non-academic centers (12.4% of the hospital database). The median prior lines of therapy was 5 (range: 4-7) and 58.4% had previously received B-cell maturation (BCMA)-directed therapies. SUD was primarily inpatient-only (79.5%) in this timeframe. CRS and ICANS occurred in 41.8% and 13.6% of patients, respectively. Although primarily administered as monotherapy, talquetamab-based combinations were observed in 9.7% of patients. Planned talquetamab bridging before BCMA chimeric antigen receptor T-cell (CAR-T) therapy also occurred in 14.4% of patients. Transition to less frequent dosing occurred over time. Among patients with ≥6 months of follow-up (n=95), common dosing schedules were Q2W (55.8%) and every 4 weeks or longer (32.6%). Although limited by lack of information regarding toxicities, our nationwide analysis of real-world patterns within 2 years of commercial talquetamab availability demonstrate the emerging usage of less frequent dosing, pre-CAR-T bridging, and talquetamab-based combinations.