Completed Phase 1 MAD Clinical Trial

During 2021, following analysis of the preliminary pharmacokinetic (“PK”) data from our Phase I multiple ascending dose (“MAD”) clinical trial, Liminal BioSciences announced that the Company would not be progressing the development of fezagepras for the treatment of idiopathic pulmonary fibrosis (IPF) nor hypertriglyceridemia.

The pharmacokinetics observed following administration of fezagepras at all doses in the MAD clinical trial (up to 2400mg daily for 14 days in single or divided doses) demonstrated that the major metabolite of fezagepras was the glutamine conjugate. The conjugation of fezagepras with glutamine shows that fezagepras has the potential to act as a “nitrogen scavenging” drug. Nitrogen scavenger drugs are used in the treatment of conditions characterized by hyperammonemia. At this stage, any potential new indications for the development of fezagepras are not expected to be in the treatment of fibrosis. There were no significant drug related safety findings in the clinical trial.

Planned Phase 1a SAD Clinical Trial Design

Fezagepras has entered a Phase 1a single ascending dose, randomized, open label, cross over clinical trial in May 2022 in the United Kingdom to provide comparative data with Sodium Phenylbutyrate, an established nitrogen scavenging drug, to support its development plan in the treatment of pathology characterized by hyperammonemia. The clinical trial aims to evaluate the safety, tolerability, and pharmacokinetics of single ascending dose of fezagepras compared to Sodium Phenylbutyrate in healthy subjects.