Treatment strategy for acquired pure red cell aplasia: a systematic review and meta-analysis.

The treatment of autoimmune acquired pure red cell aplasia (aPRCA) is challenging. Guidelines are based on expert recommendations in the absence of controlled trials. We assessed the efficacy of the main treatment strategy through a systematic review and meta-analysis using MEDLINE, EMBASE and the Cochrane library up to September 2022. The overall response rate (ORR) was pooled using random-effects models. 24 observational studies (19 retrospective, median follow-up 48 months) encompassing 753 patients (49% men) were included. Primary aPRCA represented 57% of the cases. The risk of bias was moderate to high using the ROBINS-I tool. Substantial heterogeneity (I2 >50%) was retrieved. Corticosteroids as monotherapy as first-line (186 patients, 13 studies) provided an ORR of 47% (95%CI, 34-60). Cyclosporine A was the most frequently used immunosuppressant agent (384 patients, 18 studies), providing an ORR of 74% (95%CI, 66-82) with a similar ORR in first (73%) and second-line (76%) and when cyclosporin was used as monotherapy (83%) or with corticosteroids (77%). 112 patients (10 studies) received cyclophosphamide with an ORR of 49% (95%CI, 35-64) which was higher when cyclophosphamide was combined with corticosteroids (48%) and in second-line (58%) than in monotherapy (31%), and in first-line (44%). Sirolimus use was reported only after cyclosporine A failure and provided an ORR of 87% (95%CI 68-100, 64 patients, 3 studies). Substantial uncertainty remains regarding the best treatment strategy in the absence of high-quality evidence. This study was registered on the PROPERO database as #CRD42022360452.