Belantamab Mafodotin in Relapsed/Refractory AL Amyloidosis: Real-World Multi-Center Experience and Review of the Literature

Introduction: Treatment for relapsed/refractory AL amyloidosis (AL) is an unmet need. The safety and efficacy of belantamab mafodotin (BLM) in multiple myeloma are known, whereas in AL data are limited. Methods: We report a multi-center cohort of AL patients receiving BLM, and review all previous data on BLM therapy in AL. Results: Twelve patients with a median of 3 (range 2-9) prior lines of therapy were included. The overall hematological response rate (ORR) was 75% (9/12), including 5 complete responses. Six of the 10 evaluable patients had organ responses. The median event-free survivals/overall survivals were 22.3 and 28.8 months, respectively. Grade 3 toxicities were mostly infections and keratopathy, occurring in 7/12 (58%). Hematological toxicities were rare. No grade 4/5 toxicities occurred. The review of the previous series reveals BLM provides an ORR of 60-83% with similar rates of corneal toxicity. Conclusion: BLM, being an off-the-shelf therapy, with acceptable toxicity even in frail patients, may be a valuable option in AL, with a high ORR, and a signal for durable responses and high-quality organ responses.