ASRS 2025: PER-001 improved structure and visual function in patients with diabetic retinopathy

Justis Ehlers, MD, FASRS, a retina surgeon from the Cole Eye Institute at the Cleveland Clinic, presented at the 2025 annual meeting of the American Society of Retina Specialists (ASRS). The meeting was held in Long Beach, California, from July 30 through August 2, 2025.

His presentation, titled "PER-001, a Long-acting Endothelin Antagonist Intravitreal Implant, Improved Structure and Visual Function in Patients With Diabetic Retinopathy," focused on a study of PER-001, a novel therapeutic targeting the endothelin-1 receptor, a potent vasoconstrictor in the human body.

This treatment candidate aims to address challenges in diabetic retinopathy and potentially improve retinal function. The phase 2A study was designed to evaluate the effectiveness of PER-001 through a comparative analysis between 2 different dosage groups and a sham group. The research specifically targeted patients with diabetic retinopathy without diabetic macular edema (DME), who typically maintain good central visual acuity but may experience early-stage visual complications. Key research findings revealed promising results across functional and structural end points. Functionally, the study observed clear trends in the treatment groups, with potential improvements in:

• Retinal sensitivity
• Low contrast visual acuity

Structurally, quantitative ultrawidefield angiography demonstrated positive signals in:

• Macular ischemia reduction
• Decreased macular leakage
• Reduction in microaneurysms

The sham group consistently showed progressive worsening across these parameters, highlighting the potential efficacy of the PER-001 therapeutic approach. A notable aspect of the study is the extended-release implant system, similar to existing dexamethasone implants. This innovative delivery mechanism suggests the possibility of limited dosing, potentially every 6 months, which could significantly improve patient treatment convenience and adherence.

The research represents an important step in understanding how endothelin-1 receptor antagonists might address vascular and inflammatory challenges in retinal conditions. The mechanism's potential to impact ischemia, inflammation, and vascular leakage opens promising avenues for future therapeutic interventions. Moving forward, the research team plans to conduct a phase 2B/3 study, with a primary focus on evaluating the duration and durability of the PER-001 therapeutic approach. This next phase will be crucial in determining the long-term potential of this innovative treatment strategy for patients with diabetic retinopathy.