Autoimmune Cytopenias

At the 63rd Annual Meeting of the American Society of Hematology (ASH), researchers from Peking University People's Hospital, Peking University Institute of Hematology, and other centers in Beijing, China, presented results (abstract 15) of their multicenter study evaluating the efficacy and safety of combination treatment with all-trans retinoic acid (ATRA) plus low-dose rituximab (LD-RTX) vs LD-RTX monotherapy in 168 patients with corticosteroid-resistant or relapsed ITP (ClinicalTrials.gov Identifier: NCT03304288). The investigators hypothesized that, "a combination of RTX and ATRA may work synergistically based on a 'double-hit' mechanism targeting both platelet production and destruction, which may overcome the long TTR [time to treatment response] and improve the SR [sustained remission] rate of LD-RTX." Patients with platelet counts less than 30×10⁹/L or bleeding symptoms and corticosteroid-resistant or relapsed ITP were randomized 2:1 to receive 100 mg of RTX weekly for 6 weeks plus ATRA orally at 20 mg/m² daily for 12 weeks (n=112) or 100 mg of RTX weekly for 6 weeks (n=56). All patients were followed up for more than 11 months. In the combination group, an overall response was observed in 80.4% of patients, compared with 58.9% in the LD-RTX monotherapy group. At 6-month follow-up, 60.7% of patients in the combination group vs 41.1% of those randomized to monotherapy had achieved SR. At 12 months, SR persisted in 50% of patients in the combination group vs 34% of patients in the monotherapy group. TTR was not significantly different between the 2 treatment groups. Adverse events (AEs) were primarily grade 1 or 2; in the combination group, the most common AEs were dry skin (40.2%) and headache or dizziness (18.8%). The researchers concluded that "ATRA plus LD-RTX significantly increased the overall and sustained response, indicating a novel promising treatment option for corticosteroid-resistant or relapsed adult ITP patients."