Thalidomide-Hydroxyurea Combo More Effective for Sickle Cell Anemia, suggests research
Researchers have found in recent clinical trial conducted in India that combining thalidomide with hydroxyurea (HU) significantly outperformed HU alone in treating sickle cell anemia (SCA). The combination improved hemoglobin levels, reduced painful vaso-occlusive crises, and lowered the need for blood transfusions, demonstrating both safety and greater efficacy over HU monotherapy.
The clinical course of sickle cell anemia (SCA) is variable, with chronic hemolysis and end-organ damage caused by microvascular occlusion. We evaluated the efficacy and safety of thalidomide plus hydroxyurea (HU) compared with HU alone to determine whether the combination provides a superior clinical benefit and safety profile.
This was an open-label quasi-experimental clinical trial (Clinical Trials Registry of India, CTRI Registration Number 2023/04/065682). Patients with SCA aged > 12 years and postmenopausal females aged > 45 years were allocated 1:1 to receive either HU (20 mg/kg/day) and thalidomide (50 mg/day) in Group A or HU (20 mg/kg/day) only in Group B.
Results: The frequency of vaso-occlusive crises (VOCs), transfusion requirements, variations in hematological parameters (hemoglobin [Hb], fetal hemoglobin [HbF], and sickle hemoglobin [HbS]), and side effects between the groups were assessed over 12 months. Repeated-measures analysis of variance was used to determine changes across the observation period. The mean age of the 66 patients diagnosed with SCA (homozygous HbS mutation) was 32.9 (standard deviation ± 11.5) years, and 57.6% were males. Over the 12-month observation period, Group A had significantly fewer VOCs (3.48 ± 2.81) and packed red blood cell transfusions (3.61 ± 2.19) than Group B (11.36 ± 4.20 VOCs; 13.27 ± 3.70 transfusions) (p = 0.0001).
There was a significant increase in Hb (8.2 ± 1.8 to 11.8 ± 1.2 g/dL), a decrease in HbS% (72.5 ± 5.5 to 64.5 ± 5.4), and a rise in HbF% (18.9 ± 5.1 to 28.4 ± 5.6) (p < 0.0001) in Group A. Combining thalidomide with HU significantly reduced VOCs and transfusion requirements, improved Hb and HbF%, and decreased HbS levels.
Reference:
Samal, P., Paul, A., Bahirat, H. et al. Efficacy and safety of thalidomide with hydroxyurea in sickle cell anemia: a quasi-experimental clinical trial. Blood Res. 60, 21 (2025). https://doi.org/10.1007/s44313-025-00068-4
