Efficacy and safety of romiplostim N01 for refractory aplastic anemia: A retrospective single‑center study

Abstract Objective: To evaluate the efficacy and safety of romiplostim N01 in patients with refractory aplastic anemia (AA). Methods: Data from patients with refractory AA after full-dose of cyclosporine and at least two different oral thrombopoietin receptor agonists（TPO-RAs）between May 2024 and December 2024 at Peking Union Medical College Hospital were retrospectively reviewed. Those had been treated with Romiplostim N01 for ≥3 months and followed for ≥6 months were enrolled into the final analysis. Information including demographics, clinical characteristics, treatment response, adverse events, prognosis, and clonal evolution were collected. Results: A total of 32 patients were enrolled, with a median age of 62 years (range: 24–79); 34.4% (11/32) were males. 30 had transfusion-dependent non-severe aplastic anemia (TD-NSAA), and 2 had severe aplastic anemia (SAA). The median treatment duration was 5 (range: 3–10) months, and the median follow-up was 6 (range: 6–10) months. The overall response rates (ORR) at 3, 6-month and at last follow-up were 71.9%, 75.0%, and 75.0%, respectively; the complete response rates (CRR) at the same time points were 28.1%, 28.1% and 31.2%, respectively. The median time to achieve overall response (OR) was 1 month (range: 1–4), and the median time to complete response (CR) was 3 months (range: 1–4). At 3, 6 months and last follow-up, the hemoglobin concentration and platelet count were significantly increased compared with those at the baseline (all P < 0.05). The incidence of adverse events (AEs) was 43.8%, all were grade I and recoverable. By the end of follow-up, relapse occurred in 9.4% (3/32) of patients, and 6.3% (2/32) developed newly detected gene mutations associated with myelodysplastic syndromes (MDS). No clonal evolution to PNH was observed. No deaths occurred during the follow-up period. Conclusion: Romiplostim N01 was efficacious and well-tolerated in patients with refractory AA.