PolyActiva enrolls first patient in phase 2b clinical trial of PA5108 ocular implant

(Image Credit: AdobeStock/ImageFlow)

PolyActiva has enrolled the first patient in its phase 2b clinical trial evaluating PA5108, an investigational, new chemical entity (NCE), intracameral ocular microimplant, for the reduction in intraocular pressure (IOP) for patients with primary open-angle glaucoma (POAG) and ocular hypertension (OHT).

PA5108 is a rod-shaped, biodegradable microimplant designed to significantly reduce IOP consistently over 6 months, according to the company. The implant is engineered using PolyActiva’s PREZIA technology platform to provide a “constant, zero-order drug release and complete and predictable biodegradation, leaving no residual material in the eye.”

Jerry St. Peter, CEO and board director of PolyActiva, commented on the patient enrollment in a press release from the company, saying, “The launch of our US Phase 2b study represents a significant milestone in our efforts to address the persistent challenge of daily eye drop compliance in glaucoma care.”

St Peter continued, “With PA5108, we’re aiming to revolutionize the treatment paradigm by offering a long-acting, biodegradable implant that can be repeat-dosed every 6 months to deliver long-term, sustained IOP control. We are proud to collaborate with leading investigators, and we are deeply appreciative of the individuals taking part in this study as we work to bring this transformative option to people living with glaucoma.”

The phase 2b trial will assess the safety and efficacy of redosing PA5108 for a total of 2 implants in the study eye and will enroll approximately 75 patients across 12 clinical sites in the US monitored for up to 58 weeks. Patients will be randomized to receive PA5108 at either an 80 mcg or 160 mcg dose in one eye and topical latanoprost in the fellow eye, while the control group will be randomized to receive topical latanoprost in both eyes. At week 26, patients will receive a second implant. The primary outcome of the study is the change in mean diurnal IOP (measured at 8am, 10am, and 4pm) from unmedicated baseline at 12 weeks.

This phase 2b US trial follows a successful phase 2a trial in Australia, where PA5108 showed a >20% reduction in IOP at 12 weeks and 26 weeks. Additionally, PA5108 consistently delivered reductions in IOP for 6 months from a single implant. In a further cohort, the implant’s rapid biodegradation profile also allowed for 8 patients to receive a second implant at 21 weeks, with no product-related adverse effects.

The company noted 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 of PA5108 and 48 weeks of monitoring to date.

The company’s PREZIA drug delivery platform underpins PA5108 and other candidates in the company’s pipeline. The company states that 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. Additionally, the platform’s biodegradable design eliminates residual buildup and supports repeat dosing, according to the company.

References:

1. PolyActiva Announces First Patient Enrolled in US Phase 2b Clinical Trial of its Ocular Micro Implant for Glaucoma and Ocular Hypertension. Published August 6, 2025. Accessed August 12, 2025. https://www.businesswire.com/news/home/20250806585386/en/PolyActiva-Announces-First-Patient-Enrolled-in-US-Phase-2b-Clinical-Trial-of-its-Ocular-Micro-Implant-for-Glaucoma-and-Ocular-Hypertension

2. Harp MD. PolyActiva reports promising results from Phase 2a clinical study of biodegradable implant for treatment of mild to moderate glaucoma. Published November 2, 2023. Accessed August 12, 2025. https://www.ophthalmologytimes.com/view/polyactiva-reports-promising-results-from-phase-2a-clinical-study-of-biodegradable-implant-for-treatment-of-mild-to-moderate-glaucoma