Experience with combination of hydroxyurea and low-dose thalidomide in transfusion-dependent beta thalassemia patients.

Hydroxyurea (HU) and thalidomide have been reported to improve clinical and hematological parameters in transfusion-dependent beta thalassemia (TDT). Therefore, we retrospectively analyzed the combination of HU and thalidomide in 140 transplant ineligible TDT, ≥ 10 years old, visiting our thalassemia clinic between October 2014 and November 2019. Responses were defined as maintenance of hemoglobin ≥9gm/dl without transfusion as complete response (CR) and with at least 50% reduction in transfusion burden as partial response (PR). Patients with less than 50% transfusion burden reduction for consecutive 6 months of therapy were defined as non-responders (NR), and treatment was discontinued thereafter. Primary end point was overall response rate (ORR) at last follow-up. At median follow-up of 22.6 (95% CI 16.4-28.7) months, 76 (57.2%) patients achieved CR and 19 (14.3%) achieved PR, accounting to an ORR of 71.5%. Among responders at last follow-up, a significant increase in the post-treatment hemoglobin (0.88±0.37gm/dl, p<0.0001) and drop in serum ferritin (-1490.5ng/ml, p<0.0001) were observed. Median time to CR was 124 (95% CI 75.3-172.6) days. Median longest continuous CR was 791 (95% CI 662.2-919.7) days. Common toxicities observed were sedation (25%), hyperbilirubinemia {(23.57%, grade 3/4 =17 (12.14%)}, and constipation (22.8%). Nearly three-fourth of the patients has responded with majority having CR. Adverse events are a concern; hence, regular close monitoring is a prerequisite.