Company: AGIO
Filing Date: 2025-05-01
Form Type: 10-Q
Source: 0001439222-25-000036
Chunk: 140

Company: AGIOS PHARMACEUTICALS, INC.
Filing Date: 2025-05-01
Form: 10-Q
Item: Part I, Item 8
Chunk 140
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 through week 32 of the double-blind period. Using Bayesian methodology, the prespecified statistical criterion for the primary endpoint in ACTIVATE-kidsT was not met using low or moderate borrowing of data from the ACTIVATE-T study in adults. In the study, 28.1% of patients in the mitapivat arm achieved the primary endpoint of transfusion reduction response, compared to 11.8% of patients in the placebo arm. Transfusion-free response and normal hemoglobin response were secondary endpoints in this study and only observed in patients in the mitapivat arm. In the 32-week double-blind treatment period, mitapivat was generally safe and well-tolerated, with safety results consistent with the safety profile for mitapivat previously observed in adults with PK deficiency who are regularly transfused.

We announced topline data for ACTIVATE-kids in February 2025. A total of 30 patients were enrolled in ACTIVATE-kids, with 19 randomized to mitapivat twice-daily and 11 randomized to matched placebo. All patients in both treatment arms completed the 20-week double-blind period of the study. The primary endpoint of ACTIVATE-kids is percentage of patients with hemoglobin response, defined as ≥1.5 g/dL increase in hemoglobin concentration from baseline that is sustained at two or more scheduled assessments at weeks 12, 16, and 20 during the double-blind period. Using Bayesian methodology, the prespecified statistical criterion for the primary endpoint in ACTIVATE-kids was met using a range of relative borrowing from the adult ACTIVATE study, for all possible borrowing weights (ranging from 0 to 1). In addition, the pre-specified supportive analysis based on traditional methodology comparing the hemoglobin response rate 

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for mitapivat versus placebo provided further evidence that the primary endpoint was met. There were 31.6% of patients in the mitapivat arm achieving a hemoglobin response compared to 0% of patients in the placebo arm; the 95% confidence interval for the difference in hemoglobin response rates between mitapivat and placebo was >0 (95% CI=10.8% to 52.7%). In addition, improvements in changes from baseline for markers of hemolysis (indirect bilirubin, lactate dehydrogenase and haptoglobin) were observed in the mitapivat arm compared to the placebo arm. In the 20-week double-blind period of the study