08:15 AM EST, 11/19/2025 (MT Newswires) -- Agios Pharmaceuticals ( AGIO ) shares were down 45% in Wednesday's premarket activity after it reported that its potential sickle cell disease treatment mitapivat failed to meet one of two primary endpoints in a 52-week phase 3 clinical trial.

While the trial met its primary endpoint of hemoglobin response, mitapivat failed to show a statistically significant reduction in the annualized rate of sickle cell pain crises compared with a placebo in patients 16 years or older with sickle cell disease, the company said.

Mitapivat also showed statistically significant improvements in the two key secondary endpoints while failing to meet a third of reducing fatigue, the company said.

The company said it plans to meet with the US Food and Drug Administration to discuss a plan to bring to market and intends to submit a marketing application for mitapivat in the US for sickle cell disease after having a pre-supplemental new drug application meeting with regulators in Q1.

Price: 25.00, Change: -20.49, Percent Change: -45.04