Barreling toward the end of its cash runway, GRI Bio has shared phase 2a data in idiopathic pulmonary fibrosis (IPF) and made the case for further development of its potentially disease-modifying therapy.
The phase 2a study randomized 35 people with IPF to receive GRI-0621 or placebo. GRI-0621 is an oral drug candidate that is designed to inhibit invariant natural killer T-cell activity. Because the cells play a role in inflammatory and fibrotic indications, GRI believes the mechanism could represent a new option for IPF patients whose choices are currently limited to three medicines.
After 12 weeks of once-daily oral dosing, GRI found no safety or tolerability concerns, hitting the trial’s primary endpoint. Four-fifths of patients were taking Esbriet, which Legacy Pharma recently bought from Roche, or Boehringer Ingelheim’s Ofev. GRI sees safety as one area in which GRI-0621 may have an edge over the incumbent treatments.
Secondary endpoints looked at biomarkers and, in an exploratory analysis, lung function. GRI presented data on biomarkers of collagen synthesis and degradation as evidence that GRI-0621 induced resolution of fibrosis.
Existing IPF treatments, including Boehringer’s recently approved Jascayd, slow disease progress rather than halt or reverse fibrosis and its effect on lung function. A drug that resolves fibrosis would represent a leap forward, but GRI is still some way off from showing GRI-0621 can achieve that goal.
The biotech included FVC, a measure of lung function, as an exploratory endpoint in the phase 2a trial. At Week 12, GRI saw increases in FVC in 39% of patients on GRI-0621. Conversely, FVC decreased in 80% of patients on placebo.
Adjusted for placebo, FVC increased by 99 mL in patients on GRI-0621 and 139 mL in participants who received GRI’s drug candidate with the standard of care. The biotech also shared the findings of a post hoc analysis that excluded patients with the biggest FVC gains and losses in both arms. In that analysis, the placebo-adjusted gains were 54 mL on GRI-0621 and 81 mL in people who also took standard of care.
GRI CEO Marc Hertz, Ph.D., said in a statement that the data put the biotech in a good position to move into the next stage of development.
The company told investors in November that it could fund operations into the first quarter of 2026. GRI subsequently offered stock and warrants to raise money. The biotech has a market cap of $4 million and saw its stock slip slightly in premarket trading after the data drop.