Outpatient step-up dosing of teclistamab and talquetamab in relapsed or refractory

Bispecific T-cell-engaging antibodies against BCMA and GPRC5D demonstrate high efficacy in relapsed/refractory multiple myeloma (RRMM) but are associated with cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS), traditionally prompting inpatient monitoring when commencing therapy. Contemporary step-up dosing and prophylactic strategies may enable safe outpatient administration.

We conducted a single-center retrospective study evaluating outpatient step-up dosing (SUD) of teclistamab or talquetamab in adults with RRMM. Patients met institutional outpatient eligibility criteria and received standard pre-medications; prophylactic tocilizumab was administered at physician discretion. The primary endpoint was incidence and severity of CRS/ICANS. Secondary endpoints included SUD completion, healthcare utilization, and need for hospitalization.

Thirty-eight patients underwent 43 outpatient SUD initiations (teclistamab n = 30; talquetamab n = 13). Median age was 72 years, and disease burden was high. SUD completion occurred in 93%. CRS occurred in 26% of initiations and was exclusively grade 1-2; no grade ≥ 3 CRS occurred. One possible grade III ICANS event (2%) occurred after completion of SUD. CRS incidence was similar with and without prophylactic tocilizumab (29% vs 32%). Most events occurred during the first two step-up doses. Hospitalization occurred in 5 (12%) SUD initiations for CRS/ICANS events and overall healthcare utilization was modest.

Outpatient administration of teclistamab and talquetamab SUD in RRMM is feasible and safe with low rates of low-grade CRS. Toxicities occur early and are manageable with structured monitoring, supporting outpatient delivery in appropriately selected patients.