ASH Report: Luspatercept and Iron
December 6, 2020 – The effect of long-term luspatercept use on iron levels and on utilization of iron chelation therapy was assessed in the Phase 3 BELIEVE trial of luspatercept in adult patients with transfusion-dependent beta thalassemia.
After 24 weeks of treatment, 17.0% of patients who took luspatercept showed a reduction in serum ferritin levels from ≥ 1,000 μg/L to below 1,000 μg/L, compared with only 5.0% of patients treated with placebo.
After 48 weeks of treatment, 9.7% of patients taking luspatercept showed a reduction in Liver Iron Concentration (LIC) from >3 at baseline to ≤3 mg/g dry weight, compared with only 5.9% of patients treated with placebo. Also after 48 weeks of treatment, 20% of patients taking luspatercept showed an improvement in cardiac iron T2* from ≤ 20 ms at baseline to > 20 ms, compared with only 9.1% of patients treated with placebo.
No significant difference in iron chelation therapy was observed between luspatercept- and placebo-treated patients during the first 48 weeks of the study. However, the proportion of patients taking 1 or more iron chelation medications gradually declined in luspatercept-treated patients relative to patients taking placebo over longer time periods. Luspatercept-treated patients also experienced a gradual decrease in mean daily dose of deferasirox over time.
In summary, a higher percentage of luspatercept-treated patients compared to placebo-treated patients experienced reductions in serum ferritin levels, Liver Iron Concentration, and cardiac iron levels in the first 48 weeks of the BELIEVE Study. This suggests that luspatercept-treated patients may be at lower risk of the complications associated with iron overload. Long-term luspatercept treatment also led to decreasing trends of iron chelation therapy use and deferasirox dosage.
Further information about the reduction in iron levels observed with luspatercept treatment is available in the ASH meeting abstract at: https://ash.confex.com/ash/2020/webprogram/Paper136517.html