ZETA-1: APX3330 outperforms placebo in slowing progression of diabetic retinopathy

Key Takeaways

  • APX3330 is an oral, small-molecule drug in development for the treatment of diabetic retinopathy.
  • It reduced the percentage of patients who developed proliferative (advanced stage) diabetic retinopathy over the six month study period.

Ocuphire Pharma conducted the multicenter, randomized, placebo-controlled phase 2 ZETA-1 trial to test the safety and efficacy of an oral medication called APX3330 for the treatment of diabetic retinopathy (DR). The trial enrolled 103 adults with moderately severe to severe nonproliferative diabetic retinopathy (NPDR) (the early stage of diabetic eye disease) or mild proliferative diabetic retinopathy (the more advanced stage of diabetic eye disease). Researchers used the Diabetic Retinopathy Severity Scale, a 12-step standardized scale that classifies diabetic retinopathy severity, to assess patient eligibility, and participants were assigned to the small-molecule drug APX330 or placebo twice daily for 24 weeks. 

According to study results presented by Veeral Sheth, MD, MBA, FACS, FASRS at the virtual Angiogenesis, Exudation and Degeneration 2024 conference, oral APX3330 showed clinically meaningful response compared with placebo in slowing progression of diabetic retinopathy. Only 5% of patients treated with APX330 had at least three-step worsening on the binocular DRSS person-level scale compared with 13% on placebo. In addition, APX3330 reduced the percentage of patients who developed proliferative diabetic retinopathy over the study period, and fewer patients treated with APX3330 lost visual acuity compared with placebo. 

Researchers reported limited adverse events, mostly mild in severity and similar to or fewer than those with placebo. Patients were able to continue their routine medications for diabetes comorbidities. 

“Given its favorable safety profile, APX3330 may represent a promising oral treatment option for delaying or preventing disease progression in patients with NPDR who otherwise are monitored and untreated until they progress to sight-threatening disease,” George Magrath, MD, MBA, MS, Ocuphire’s CEO, said in related press release. “We look forward to advancing our oral APX3330 program.” Ocuphire plans to submit a special protocol assessment to initiate a phase 3 trial.

Source: Kate Young, Healio Optometry News, February 9, 2024; see source article