The FDA extended its decision timeline for Agios Pharmaceuticals’ supplemental NDA seeking additional approval for mitapivat in sickle cell disease. The agency pushed the PDUFA target action date by three months to February 1, 2027, after requesting additional information tied to whether a Risk Evaluation and Mitigation Strategy (REMS) would be required. Agios said the amendment was triggered by FDA’s assessment needs around safety management for mitapivat in SCD. In response, the company submitted updated safety data through October 9 from ongoing open-label extension periods of the RISE UP trial (NCT05031780). Agios referenced data published October 24 in The Lancet showing hemoglobin response in 41% (56 of 138) of patients receiving mitapivat versus 3% (2 of 69) on placebo. The company also said its analysis continued to show no hepatocellular injury cases among SCD patients with safety patterns and severity comparable to earlier adult thalassemia findings. Investors reacted negatively to the delay, with Agios shares down nearly 18% in response. The move indicates regulators remain focused on the conditions under which the therapy could be used and monitored in SCD.