Belantamab mafodotin, pomalidomide, and dexamethasone for triple class exposed/refractory relapsed multiple myeloma: a subgroup analysis of the ALGONQUIN trial.

Given the early use of triplet and quadruplet regimens, most patients with multiple myeloma (MM) will be exposed and/or refractory to PIs, IMiDs, and anti-CD38 mAbs after first- or second-line treatment. Effective treatment for this group of triple class exposed/refractory (TCE/R) patients is crucial. Here we present a post-hoc subgroup analysis of TCE/R patients treated on the ALGONQUIN study of belantamab mafodotin plus pomalidomide-dexamethasone (belamaf-Pd) for relapsed MM. Of the 99 patients treated on the ALGONQUIN study, 69 were TCE and 56 were TCR and were included in this analysis. Patients had a median of three prior lines of therapy. The ORR was 86.4% in TCE patients and 84.9% in TCR patients, with ≥ very good partial response rates of 64% and 68% respectively. The median progression free survival was 18.3 months in TCE patients and 19.6 months in TCR patients, with overall survival not yet reached and 34.4 months, respectively for TCE and TCR patients. No new safety signals were identified. The most common Grade ≥ 3 AEs were keratopathy (48%), decreased visual acuity (42%), neutropenia (36%), thrombocytopenia (27%), and infection (25%). In this subgroup analysis of the ALGONQUIN study, patients with TCE/TCR disease treated with belamaf-Pd achieved high clinical response rates with durable remissions, comparable to other novel therapeutics in this space.