Now that the FDA has lifted a partial hold on the PRO-101 trial, ProJenX said it will start enrolling US patients with amyotrophic lateral sclerosis (ALS) later this year in the Phase I safety study of the oral, brain-penetrant MAP4K inhibitor prosetin.
The New York-based biotech is evaluating lead candidate prosetin in the three-part PRO-101 study. The first two parts, which evaluated the safety of prosetin in healthy volunteers, wrapped up at the end of 2022, according to ClinicalTrials.gov. The third part will assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of prosetin in patients with ALS.
The regulatory go-ahead comes soon after Canadian and European authorities issued their respective greenlights for the third part of the trial. Sites in Canada and the Netherlands are expected to begin enrolling patients with ALS in the second quarter, ahead of US enrollment.
ProJenX did not disclose why the partial hold was implemented in the first place, although chief operating officer Erin Fleming said in a statement that the agency had “limited prosetin dose levels.”
The company believes prosetin could be a potent ALS treatment because multiple patient stem cell-derived models of the neurodegenerative disease have shown MAP4K inhibition can confer motor neuron protection.