Efficacy and Safety of Weekly Bortezomib-dexamethasone as the Third-Line Therapy for Warm Autoimmune Hemolytic Anemia: a Case Series of 5 Patients.

Warm autoimmune hemolytic anaemia (wAIHA) is a chronic condition. Despite the high initial responses seen with the first two treatment lines (corticosteroids and rituximab), relapses are frequent. Anecdotal data suggests the efficacy of bortezomib in relapsed/refractory (RR) wAIHA. This case series aimed to evaluate bortezomib as a third-line therapy in wAIHA in terms of efficacy, safety, and prospects of achieving treatment-free remission (TFR). Five adult patients ≥ 18 years of age with RR wAIHA after corticosteroids and rituximab were included over 1.5 years. Patients were treated uniformly with Vd (4 weeks = 1 cycle), bortezomib (1.3 mg/m subcutaneous/week), and dexamethasone (40 mg/week). Patients were assessed for response, side effects, and TFR following bortezomib discontinuation. The median age was 40 years (range, 17-55), and 60% were females. The overall response rate was 100%. The median time to partial response (PR) was 1 month (range, 0.5-4). With ongoing treatment, three patients achieved a complete response (CR). The median time to best response (PR- 40%, CR- 60%) was 4 months (range, 1-19.5). After a median follow-up of 21 months following bortezomib discontinuation, TFR rates were 60%, 40%, and 20% at 6 months, 1 year, and 2 years, respectively. Non-severe treatment-related thrombocytopenia was seen in 1/5 of patients. For patients with RR wAIHA, Vd represents a safe and highly effective third-line therapy with durable responses and high TFR rates.