Oculis Holding AG has completed enrollment in both of its pivotal Phase 3 DIAMOND trials evaluating OCS-01 eye drops for the treatment of diabetic macular edema (DME), marking a significant milestone in the development of what could become the first non-invasive topical treatment for this serious eye condition.
The DIAMOND program, which stands for "DIAbetic Macular edema patients ON a Drop," has successfully randomized over 800 patients across 119 investigative sites primarily in the United States and several other countries. The rapid enrollment pace highlights both the significant unmet need in DME treatment and the strong interest from both patients and investigators in a non-invasive therapeutic option.
"The completion of enrollment in both the DIAMOND-1 and DIAMOND-2 Phase 3 trials shows strong focus on disciplined execution," said Riad Sherif, M.D., Chief Executive Officer of Oculis. "For the months to come, we will remain focused on execution to ensure the program's continued advancement, bringing us closer to potentially providing a transformational solution, with the first non-invasive topical eye drop therapy, for patients suffering from DME."
Revolutionary Approach to DME Treatment
DME is the leading cause of visual loss and legal blindness in patients with diabetes, currently affecting an estimated 37 million people worldwide. With the rising prevalence of diabetes globally, this number is projected to increase to 53 million by 2040.
All currently available DME treatments require invasive delivery methods, such as intravitreal injections or ocular implants, to reach the retina. OCS-01 represents a potential paradigm shift in treatment approach, offering a convenient eye drop formulation that could significantly improve patient experience and potentially treatment adherence.
Arshad M. Khanani, M.D., DIAMOND Program Steering Committee Chairperson and Director of Clinical Research at Sierra Eye Associates, noted the enthusiasm surrounding the trials: "The rapid enrollment of over 800 patients in both trials not only reflects the recognition among investigators of OCS-01's significant potential as an effective, non-invasive therapy for DME, but also demonstrates the high level of patient interest in a topical eye drop treatment."
Trial Design and Technology
The DIAMOND-1 and DIAMOND-2 trials are double-masked, randomized, multi-center studies designed to evaluate the efficacy and safety of OCS-01 eye drops in patients with DME following 52 weeks of treatment. Patients have been randomized 1:1 to receive either OCS-01 or vehicle (placebo) six times daily for a 6-week induction phase, followed by three times daily through week 52 for the maintenance phase.
The primary endpoint is change in best corrected visual acuity early treatment diabetic retinopathy study (BCVA ETDRS) letter score at Week 52. Secondary endpoints include the percentage of patients with ≥15-letter gain in BCVA and change in central subfield thickness (CST), both measured at Week 52.
OCS-01 leverages Oculis' proprietary OPTIREACH® technology, a solubilizing formulation of high concentration dexamethasone. This technology addresses the main limitations of conventional eye drops by improving the solubility of lipophilic drugs, increasing residence time on the eye surface, and enabling drug passage from the eye surface to the posterior segment of the eye.
Potential Clinical Impact
If approved, OCS-01 would address significant unmet needs in DME treatment, particularly for early intervention or for patients with inadequate response to anti-VEGF therapy. The non-invasive nature of the treatment could potentially:
- Enable earlier treatment initiation, potentially preventing disease progression
- Reduce the burden of frequent clinic visits for injections
- Minimize injection-related complications
- Serve as a complementary therapy to existing treatments
Path to Approval
Topline data from both Phase 3 trials is expected in the second quarter of 2026, with New Drug Application (NDA) submission to follow. The trials were initiated following positive findings from stage 1 of the DIAMOND program, which was announced in the second quarter of 2023.
Oculis will provide an update on the progress of the Phase 3 DIAMOND-1 and DIAMOND-2 trials at its upcoming R&D Day on April 15, which will be held both in-person and virtually.
About Diabetic Macular Edema
DME is an irreversible and progressive complication of diabetic retinopathy related to consistently high blood sugar levels that damage nerves and blood vessels in the macula, the area of the retina responsible for sharp vision. The condition occurs when blood vessels in the retina swell and leak, leading to fluid build-up (edema) in the retina.
The disease represents a significant global health burden, with current treatments being effective but invasive and often requiring frequent administration. A non-invasive topical treatment option could significantly improve the treatment landscape for millions of patients worldwide.
