The study, conducted by biotechnology firm ProJenX, marks a milestone for prosetin, a selective MAP4K inhibitor designed to penetrate the blood-brain barrier. Interim results across five dose levels, ranging from 0.16 to 1.05 mg/kg/day, showed no serious adverse events related to the medication. Researchers confirmed that plasma concentrations at higher doses successfully reached levels predicted by preclinical models to be therapeutic.

Beyond safety, the data demonstrate a statistically significant reduction in phosphorylated MAP2K4, a key biomarker for MAP4K inhibition, within peripheral blood mononuclear cells. This provides direct evidence of the drug's biological activity in humans.

While the primary dosing phase is complete, participants are continuing in a two-year open-label extension. This longitudinal phase tracks functional outcomes, including the revised ALS Functional Rating Scale and neurofilament light chain levels. According to Jinsy Andrews of NYU Langone, these findings validate the transition from preclinical models to clinical application for sporadic ALS. ProJenX intends to use these results to refine eligibility criteria and endpoints for a forthcoming Phase 2 trial. Detailed findings are scheduled for presentation at the European Network to Cure ALS meeting in Madrid on June 24.