Oculis Holding AG recently announced completion of the final patient visit in the OCS-01 phase 3 DIAMOND program in diabetic macular edema (DME).
Let’s start with Oculis’ portfolio.
Oculis is a global biopharmaceutical company focused on innovation addressing ophthalmic and neuro-ophthalmic conditions with significant unmet medical needs.
Key to this goal: Developing three core assets currently in registrational trials, including:
- OCS-01 (with OPTIREACH technology) indicated for DME
- LICAMINLIMAB (OCS-02) indicated for dry eye disease (DED)
- PRIVOSEGTOR (OCS-05) indicated for optic neuritis and non-arteritic anterior ischemic optic neuropathy (NAION)
Let’s dig more into OCS-01.
OCS-01 is a novel, high-concentration (15 mg/ml) formulation of dexamethasone that utilizes Oculis’ OPTIREACH solubilizing nanoparticle technology.
Quick refresher: OPTIREACH is a proprietary platform designed to enable the formulation of drugs as non-invasive topical treatments (eye drops) by improving the solubility of lipophilic drugs—which is crucial for drug absorption, distribution, and overall effectiveness.
- To note: The patient recovery period is estimated to be around 2 to 3 hours.
And what’s the intended result of this technology for OCS-01?
The idea is for the eye drop-formulated drug to have increased solubility as well as an extended amount of residence time on the eye surface, leading to:
- Less frequent administration for the front-of-the-eye
- Drug passage from the eye surface to the posterior segment for retinal diseases (such as DME)
Now to this DME program.
The phase 3 DIAbetic Macular edema patients ON a Drop (DIAMOND) trials include 800+ DME patients across 119 global clinical sites randomized 1:1 in the following setups:
- DIAMOND-1 (NCT05066997)
- Stage 1: OCS-01 dosed 6x/day for 6 weeks followed by 3x/day for 6 weeks
- n = 148 (aged 18-85)
- Stage 2: OCS-01 dosed 6x/day for 6 weeks followed by 3x/day for 46 weeks
- n = ~400 (aged 18-85)
- Note: First patient was dosed in January 2024
- n = ~400 (aged 18-85)
- Stage 1: OCS-01 dosed 6x/day for 6 weeks followed by 3x/day for 6 weeks
- DIAMOND-2 (NCT06172257)
- n = ~400 (estimated; aged 18-85)
- OCS-01 dosed for the following setup:
- Dosed 6x/day for 6 weeks followed by 3x/day for 46 weeks
- OCS-01 dosed for the following setup:
- n = ~400 (estimated; aged 18-85)
Both are designed as double-masked, randomized, multicenter studies evaluating the efficacy and safety of OCS-01 for DME patients.
And what’s being measured?
The primary endpoint for each trial is the change in best-corrected visual acuity Early Treatment Diabetic Retinopathy (BCVA ETDRS) letter score at Week 52.
Secondary endpoints extend to:
- Percentage of patients with ≥15-letter gain in BCVA
- Change in central subfield thickness
Got it. Any clinical data from these studies yet?
Yes! Oculis released positive topline data from stage 1 of the DIAMOND-1 trial in May 2023.
- To note: The first stage’s primary target included identifying an optimal dosing regimen of OCS-01 as well as that aforementioned primary efficacy endpoint.
The crux of the data: As we previously reported, OCS-01 met its primary endpoint, demonstrating a statistically significant improvement in BCVA ETDRS score (check out the numbers) and a strong visual gain in the treatment arm.
Give me a few more numbers.
The percentage of patients who achieved ≥15-letter improvement in BCVA from baseline at Week 6 extended to:
- 25.3% of OCS-01-treated patients
- 9.8% of vehicle-treated patients
And the percentage of patients that continued this improvement until Week 12 (p = 0.009):
- 27.4% OCS-01-treated patients
- 7.5% vehicle-treated patients
See more data highlights here.
So what’s the plan moving forward?
As the last patient in the DIAMOND program completed the final study visit in April 2026, Oculis is targeting two timeframes:
- Topline data expected in June 2026
- A potential new drug application (NDA) submission in Q4 2026
Let's talk big picture: What’s the importance of OCS-01?
Arshad M. Khanani, MD, MA, FASRS, DIAMOND Program Steering Committee Chairperson, Oculus Board of Directors member, noted that a non-invasive topical option like OCS-01 could significantly reshape DME management.
- “This is especially important for patients with mild vision loss who are typically observed without active treatment, as well as for those who respond poorly to existing therapies or struggle with the burden of frequent injections,” he stated.
Nice! And is there anything in the works for Oculis’ other assets?
Per Riad Sherif, MD, CEO of Oculis: “The ongoing PIONEER registrational program evaluating PRIVOSEGTOR in optic neuropathies and PREDICT-1 the first genotype-based registrational trial to drive precision medicine in DED, with LICAMINLIMAB.”