Relative Bioavailability Studies With Mitapivat: Formulation and Food Effect Assessments in Healthy Subjects

Pyruvate kinase (PK) deficiency is a rare, hereditary, hemolytic anemia caused by mutations in the PKLR gene encoding the PK enzyme. Mitapivat (previously designated AG-348) is a first-in-class, oral, allosteric activator of PK. We report results from 5 Phase 1 trials in healthy adults to characterize and compare mitapivat pharmacokinetics across different formulations and analyze food effects on mitapivat bioavailability (Studies 1-5). Pharmacokinetic assessments were peak exposure, total exposure, time to maximum plasma concentration of mitapivat, and relative bioavailability (where appropriate). Plasma total exposure of mitapivat was similar in the fasted and fed (high-fat meal or different soft foods) states after capsule, tablet, and pediatric granule formulations. Although mitapivat administration with food reduced the rate of mitapivat absorption (delay in time to maximum plasma concentration; reduction in maximum concentration) versus dosing under fasted conditions, this was not considered clinically relevant, given the lack of effect on total mitapivat exposure. Consequently, the administration instructions for mitapivat relating to food state that "patients may take mitapivat tablets with or without food." These findings will continue to inform clinical studies and development of mitapivat in adult and pediatric patients with hemolytic anemias and may help inform healthcare professionals on mitapivat dosing/administration recommendations in clinical practice.