Outpatient Delivery of Step-Up Doses to Rapidly Initiate Monthly Doses of Bispecific Antibodies in Multiple Myeloma.

AIMS: New therapies are improving outcomes even in advanced stages of multiple myeloma.

OBJECTIVES

To describe the experience of bispecific antibodies (BsAbs) in Mexico.

RESULTS

The study included 41 patients with triple-class refractory (88%) and penta-drug refractory (61%) myeloma. The median number of prior treatment lines was 3, and the median time to response was 2 months. Step-up dosages were administered on an outpatient basis in 34 patients (83%). BsAbs were administered every 2 weeks to 19 patients (46%) and monthly to 17 patients (41.5%). Thirteen of these (31.5%) switched to monthly doses early in treatment and maintained their response. Twenty-five of 38 evaluated patients (66%) achieved a complete response or better, and 84% were negative for minimal residual disease. The median response duration was 10 months, while median progression-free survival and overall survival were 12 and 13 months, respectively. Extramedullary disease, no complete response, positivity for minimal residual disease, and penta-refractoriness were associated with poor outcomes. The adverse events were lower than those reported in clinical trials.

CONCLUSIONS

In conclusion, using outpatient step-up dosing followed by planned de-escalation to monthly doses of BsAbs in responding patients with MM is feasible, safe, and effective, and may improve access to this novel therapy.