PYC Therapeutics (ASX:PYC) said autosomal dominant optic atrophy (ADOA) patients in the ongoing clinical trials of its PYC-001 drug candidate showed sustained improvement in both visual acuity and retinal stress following repeat doses, according to a Tuesday Australian bourse filing.

Non-human primates treated with a single dose of the candidate at 15 micrograms per eye showed a sustained increase in OPA1 protein target gene expression in the retina four months after a single treatment.

Human patients are currently receiving the candidate once every two to three months. The data from non-human primates support extending the dosing interval to once every four months or more. The firm plans to review the clinical protocol for the ongoing studies with a view to extending the dosing interval in these trials.