PolyActiva has achieved a significant milestone in glaucoma treatment development with the enrollment of the first US patient in its Phase 2b clinical trial evaluating PA5108, an investigational biodegradable ocular micro implant. The trial represents a major advancement in addressing the persistent challenge of daily eye drop compliance in glaucoma care.
Novel Drug Delivery Platform Addresses Compliance Challenge
PA5108 is a new chemical entity designed as a rod-shaped, biodegradable micro implant that delivers sustained intraocular pressure (IOP) control for up to six months. The implant utilizes PolyActiva's proprietary PREZIA™ technology platform, which provides constant, zero-order drug release and complete, predictable biodegradation without leaving residual material in the eye.
The implant contains a pro-drug of latanoprost acid and is administered via a single in-office injection into the anterior chamber of the eye using a custom-built delivery device. This approach is designed to deliver chronic dosing for glaucoma patients while eliminating the need for daily eye drop administration.
"The launch of our U.S. Phase 2b study represents a significant milestone in our efforts to address the persistent challenge of daily eye drop compliance in glaucoma care," said Jerry St. Peter, CEO and Board Director of PolyActiva. "With PA5108, we're aiming to revolutionize the treatment paradigm by offering a long-acting, biodegradable implant that can be repeat-dosed every six months to deliver long-term, sustained IOP control."
Strong Phase 2a Results Support Advancement
The US Phase 2b trial initiation follows successful completion of a Phase 2a trial in Australia, where PA5108 consistently delivered IOP reductions for six months from a single implant. The Phase 2a study demonstrated that PA5108 could be repeat-dosed after the initial six months of therapy, providing the opportunity for long-term treatment.
Statistically significant IOP changes from baseline were observed for each mean diurnal measurement at weeks 12, 21, 33, and 42. The PA5108 implant has been found to be safe and well tolerated by trial participants, with no adverse impact observed on corneal endothelium following repeat dosing and 48 weeks of monitoring.
Phase 2b Trial Design and Endpoints
The Phase 2b study will assess the safety and efficacy of redosing PA5108 for a total of two implants in the study eye. Approximately 75 patients will be enrolled across 12 clinical sites in the US, with patients randomized to receive PA5108 at either an 80 mcg or 160 mcg dose in one eye and topical latanoprost in the fellow eye. A control group will be randomized to receive topical latanoprost in both eyes.
Patients will receive a second implant at week 26 after the initial implant. The primary study endpoint is the change in mean diurnal IOP, measured at 8am, 10am, and 4pm, from unmedicated baseline at 12 weeks. Secondary and exploratory endpoints will assess IOP changes over time in both implants, the safety of both implants, and patient experience.
The study will monitor patients for up to 58 weeks, with results informing dose strength and dosing frequency for a planned Phase 3 registration trial.
Clinical Significance for Glaucoma Management
"Poor adherence to daily eye drops continues to be one of the most significant challenges in glaucoma care," said Jason Bacharach, M.D., Director of Research at North Bay Eye Associates, Petaluma, California, and a key investigator in the study. "A sustained, biodegradable implant like PA5108 that can be reimplanted for chronic dosing would provide a transformative alternative for patients and clinicians alike."
Proprietary Technology Platform
The PREZIA™ drug delivery platform underpins PA5108 and other candidates in PolyActiva's pipeline. Unlike traditional polymer matrix or nanoparticle-based systems that rely on passive diffusion, PREZIA uses covalent bonding to attach therapeutic agents to a polymer backbone. This approach enables precise, consistent, and fully customizable drug release over periods ranging from one week to over one year.
The platform's biodegradable design eliminates residual buildup and supports repeat dosing. PREZIA-based therapies can be formulated as rod-shaped implants or injectable gels and are compatible with both single-agent and combination therapies for a broad range of ocular conditions. The technology allows for new patent protection over existing drugs when delivered with this platform.
