Okogen receives CDSCO authorization to advance the EMERALD Phase 1/2 study of Treyegen (OKG-0303) for acute infectious conjunctivitis in India.
Written By: Khushi Patel, PharmD
Reviewed By: Pharmacally Editorial Team
Okogen has received authorization from India’s Central Drugs Standard Control Organisation (CDSCO) to advance the EMERALD Phase 1/2 study of Treyegen (OKG-0303), an investigational fixed-dose ophthalmic combination being developed for acute infectious conjunctivitis.
EMERALD Study to Enroll More Than 300 Patients
The EMERALD study is expected to enroll more than 300 patients and will evaluate the safety, pharmacokinetics, virologic and microbiologic activity, and clinical efficacy of Treyegen. The program is also expected to generate data that could support the further development of Okogen’s AI-enabled platform for evaluating acute infectious conjunctivitis.
Okogen currently expects initial clinical data from the EMERALD study in the fourth quarter of 2026, subject to enrollment and study progress.
Treyegen Combines Three Active Agents in an Investigational Formulation
Treyegen (OKG-0303) is an investigational fixed-dose ophthalmic combination containing ranpirnase, tobramycin, and oxymetazoline.
Ranpirnase is a host-directed antiviral, while tobramycin is an established antibacterial agent and oxymetazoline is an ocular decongestant used to reduce ocular redness. The three components are being combined in a single ophthalmic formulation intended to provide antiviral and antibacterial activity while also addressing ocular redness associated with acute infectious conjunctivitis.
The individual components are not all novel drugs. Tobramycin and oxymetazoline have established clinical-use histories, while ranpirnase has previously undergone clinical development as an antiviral component. Okogen previously evaluated ranpirnase in its OKG-0301 program for acute adenoviral conjunctivitis.
The investigational aspect of Treyegen is therefore the specific fixed-dose combination of these three active agents and its development for acute infectious conjunctivitis. Treyegen itself has not received marketing approval for this indication. Its safety and clinical activity are being evaluated in the EMERALD study.
A Host-Directed Antiviral Platform with Broader Ambitions
Okogen is developing ranpirnase-based therapies across four therapeutic areas: ophthalmology, medical countermeasures, systemic antivirals, and dermatology.
The company is positioning ophthalmology as the lead clinical application for its host-directed antiviral platform. Experience generated through the ophthalmic development program could support the company’s broader efforts to develop ranpirnase-based therapies in other antiviral applications.
CDSCO Authorization Follows Earlier Regulatory Development
The current CDSCO authorization follows Okogen’s regulatory submission for the EMERALD program in April 2025. CDSCO subsequently reviewed the program in June 2026 and recommended a Phase 1/2 development approach with additional clinical and pharmacokinetic assessments.
The regulatory recommendations included systemic pharmacokinetic evaluation and assessment of viral and bacterial loads before and after treatment. The Phase 1 component is intended to support evaluation of the investigational therapy before progression through the subsequent Phase 2 component.
The CDSCO authorization advances Treyegen into clinical evaluation in India. Okogen is targeting initial clinical data from EMERALD in the fourth quarter of 2026, subject to enrollment and study progress.
For regulatory context, the authorization should be viewed as a clinical-development milestone rather than a marketing approval. Okogen continues to describe Treyegen and its ranpirnase-based programs as investigational.
Reference
Okogen Receives CDSCO Authorization to Advance the EMERALD Phase 1/2 Study of Treyegen (OKG-0303) for Acute Infectious Conjunctivitis, Okogen via TMX Newsfile, 06 October 2026
About the Writer
Khushi Patel is a Pharm.D (Linkedin) professional with a strong foundation in clinical pharmacy, patient-centered care, regulatory affairs, and pharmacovigilance, with published work on Brugada syndrome.
Her interests include regulatory affairs, pharmacovigilance, guideline integration, multimodal therapy, pharmacogenomics, and antibiogram utilization, with a focus on evidence-based clinical decision-making and medication safety.
As a Pharmacally healthcare writer, she translates clinical and scientific evidence into clear, accurate, and clinically relevant healthcare content, while continuously developing her expertise in evolving pharmacy practice.
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