A recent Phase 2 clinical trial has demonstrated that OCS-05, an innovative treatment for acute optic neuritis (AON), successfully achieved its primary safety endpoint along with secondary efficacy endpoints. AON is a rare condition characterized by acute inflammation of the optic nerve, which can result in permanent visual impairment. Affecting up to 8 in 100,000 people globally, AON often represents the first indication of multiple sclerosis.1
The Phase II ACUITY Trial, a randomized, double-blind study, involved 36 patients who had recently developed unilateral acute optic neuritis with a demyelinating origin. Patients were randomly assigned to receive either OCS-05 (2 mg/kg/day or 3 mg/kg/day) or a placebo. Of these, 33 patients received treatment and were included in the pre-specified modified intent-to-treat (mITT) analysis.
The trial’s primary objective was to evaluate the cardiac safety of OCS-05. Results indicated no significant differences in the percentage of abnormal ECG parameters between the treatment arms.
Secondary efficacy endpoints included assessments of changes in retinal structure and visual function. Retinal structure evaluations revealed a 43% improvement in ganglion cell-inner plexiform layer (GCIPL) thickness mean change from baseline in the OCS-05 (3 mg/kg/day) + steroid group compared to the placebo + steroid group at month 3. This improvement was sustained through month 6, with p-values of 0.049 and 0.052 at 3 and 6 months, respectively. A 28% improvement in retinal nerve fiber layer (RNFL) thickness mean change from baseline was observed in the OCS-05 (3 mg/kg/day) + steroid group at month 3, increasing to 30% by month 6. The associated p-values were 0.045 and 0.033 at 3 and 6 months, respectively.
Visual function changes were measured by low-contrast visual acuity (LCVA). A favorable difference in LCVA mean change from baseline of approximately 18 letters at month 3 and 15 letters at month 6 was observed in the OCS-05 (3 mg/kg/day) + steroid group compared to the placebo + steroid group. The p-values associated with these improvements were 0.004 and 0.012 at 3 and 6 months, respectively. There were no drug-related serious adverse events or adverse events leading to drug withdrawal or study discontinuation
The results highlight the potential of OCS-05, a novel peptidomimetic small molecule candidate, to become a first-in-class therapy for AON and other neuro-ophthalmic diseases. OCS-05 has received orphan drug designation from both the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for the treatment of acute optic neuritis. Additionally, the FDA has cleared an Investigational New Drug (IND) application for OCS-05.
- Â MartÃnez-Lapiscina EH, Fraga-Pumar E, Pastor X, et al. Is the incidence of optic neuritis rising? Evidence from an epidemiological study in Barcelona (Spain) 2008-2012. J Neurol. 2014;261(4): 759-767.2012.Â
Disclosures: This article was created by the touchOPHTHALMOLOGY team utilizing AI as an editorial tool (ChatGPT (GPT-4o) [Large language model]. https://chat.openai.com/chat.) The content was developed and edited by human editors. No funding was received in the publication of this article.
