Ocuphire Pharma, Inc. (Nasdaq: OCUP) (“Ocuphire”), a clinical-stage biopharmaceutical company focused on developing novel therapies for the treatment of retinal and refractive eye disorders, today announced that clinical data from its ZETA-1 trial evaluating APX3330 in diabetic retinopathy (DR) on a validated binocular person-level scale was presented yesterday at the Association for Research in Vision and Ophthalmology (ARVO) Annual Meeting, taking place May 5-9, 2024 in Seattle, Washington. The presentation, titled Oral APX3330, a Ref-1 Inhibitor, Slows Progression of Diabetic Retinopathy on a Binocular DRSS Person-Level Scale, was delivered by Daniel Su, M.D., a practicing retina specialist at Retina-Vitreous Associates Medical Group (LA Retina) in Los Angeles, California.
Presentation Highlights:
- ZETA-1 was a Phase 2, randomized, double-masked trial evaluating the efficacy and safety of oral APX3330 compared to placebo in 103 participants with DR completed in January 2023.
- A subset analysis was conducted to evaluate the efficacy of APX3330 in slowing DR progression using the target population of the planned Phase 2/3 study and the Food and Drug Administration’s (the FDA)-agreed upon registration endpoint of a 3-step change on a binocular diabetic Retinopathy Severity Scale (DRSS). This 17-step person-level scale accounts for the DRSS scores of the two eyes and then anchors the step to the worse eye. The subset comprised 68 participants from the ZETA-1 trial who had a baseline DRSS score of 47 or 53 in at least one eye and 43, 47 or 53 in the other eye.
- Analysis of the ZETA-1 Phase 2 subset using the binocular person-level scale showed that no participants in the APX3330 group had a ≥ 4-step worsening at week 24 compared to 15.2% in the placebo group, representing a 100% reduction between groups (p=0.07). Similarly, only 5.7% of APX3330-treated subjects had a ≥ 3-step worsening at week 24 compared to 15.2% of placebo subjects, representing a 62.5% reduction between groups (p=0.26).
- Fewer participants in the APX3330 group developed proliferative diabetic retinopathy (PDR) by week 24 compared to the placebo group (11% vs 26% respectively; p=0.13).
- APX3330 showed favorable safety and tolerability, with similar ocular adverse events between APX3330 and placebo groups.
“We were pleased to present at ARVO results from the ZETA-1 Phase 2 trial analyzed using both the target population and the FDA-agreed upon registration endpoint for the planned ZETA-2 phase 2/3 trial,” said George Magrath, MD, MBA, MS, CEO of Ocuphire. “Results from this subset of participants highlight that APX3330 meaningfully slows DR worsening in patients with moderate to very severe non-proliferative DR (NPDR) in both eyes, representing those who are at higher risk for developing proliferative DR. We are working closely with the FDA regarding our Special Protocol Assessment and aim to finalize the Phase 2/3 protocol soon. We believe that APX3330 has significant potential as a promising oral binocular treatment option for delaying or preventing DR progression in patients who currently lack effective options prior to developing vision-threatening complications.”