Acceleron and Celgene announced interim data from the Phase 2a study of sotatercept (ACE-011), demonstrating dose dependent increases in hemoglobin in patients with end stage renal disease (ESRD) on hemodialysis. Sotatercept, a first-in-class anemia therapy, is a soluble fusion protein that binds with high affinity to activin A and other proteins in the TGF-β superfamily and inhibits signaling through the ActRIIA receptor.
The clinical trial is a randomized, placebo-controlled, dose escalation study designed to evaluate sotatercept for the correction of anemia in patients with ESRD on hemodialysis. Patients were randomized to either placebo or one of four sotatercept dose groups (0.3mg/kg, 0.5mg/kg, 0.7mg/kg, or 0.7mg/kg loading dose followed by 0.4mg/kg).
Results from the two lowest dose level cohorts (0.3mg/kg and 0.5mg/kg) are summarized below:
- Hemoglobin increase ≥1.0g/dL was achieved by 20%, 37% and 40% of patients in the placebo, sotatercept 0.3mg/kg and sotatercept 0.5mg/kg cohorts, respectively, in the first 28-day cycle following a single dose.
- The mean peak hemoglobin increase in the first 28-day dose cycle was 0.1g/dL, 0.5g/dL and 0.8g/dL in patients in the placebo, sotatercept 0.3mg/kg and sotatercept 0.5mg/kg cohorts, respectively.
- Rescue therapy with erythropoietin, if hemoglobin levels fell to < 9g/dL, was required in 40% of placebo patients, 13% of patients at sotatercept 0.3mg/kg, and 0% of patients at sotatercept 0.5mg/kg.