Novel implants show promise in drug delivery – Vista Center for the Blind and Visually Impaired

Key Takeaways

Drug eluting implants may provide efficient, sustained drug delivery, overcoming barriers to penetration of glaucoma drugs into the eye.
Implants could also reduce patient confusion and improve compliance and ease of treatment as compared to the use of eye drops.

Drug-eluting implants in various stages of study and approval may provide efficient, sustained drug delivery, overcoming barriers to penetration, according to a presentation at Kiawah Eye by Neel R. Desai, MD. “Only 0.001% of a topical drug is thought to be accessing the retina, and 5% accesses the anterior segment [front third of the eye]. And then there are the other barriers to entry: patient confusion, poor compliance, challenges with instillation of drops, side effects yielding poor compliance and perhaps premature discontinuation of drops,” Desai said.

One technology that is FDA approved for glaucoma and ocular hypertension (high intraocular pressure, IOP) is iDose TR (Glaukos), a small device designed to be implanted in the eye for continuous elution of the glaucoma drug travoprost. Topline clinical data showed noninferiority to the glaucoma drug timolol (eye drops) over 3 months, with a 5.8 mm Hg reduction of IOP. “Over 12 months, 81% of iDose TR subjects were completely free of their IOP drops topically, and 69% of those patients had a continued IOP-lowering benefit at 3 years compared to timolol,” Desai said.

The SpyGlass implant (SpyGlass Pharma) has a large reservoir designed to elute the glaucoma drug bimatoprost for up to 3 years. “In a phase 1 trial, 23 subjects in low, mid and high dosing showed comparable results with all three doses with a 44% mean IOP reduction. All these patients were off topical drops,” Desai said.

The Gemini capsule (Omega Ophthalmics) is a three-dimensional implant that serves as a platform for drug delivery technologies. A study performed in Costa Rica on 30 patients with 1 year follow up showed good safety.

Finally, the OcuRing (LayerBio) is a bioerodible (degrades in the eye) sustained-release implant that is implanted during cataract surgery and elutes the glaucoma drug ketorolac. In a phase 1 study, it was tested in five patients. “All these patients were clear of any inflammation, no steroids were given per the protocol, and no study patient required rescue therapy,” Desai said. The OcuRing could be adapted to elute a combination of NSAIDs (non-steroidal anti- inflammatory drugs) and corticosteroids or antibiotics, allowing for drop-free cataract surgery.

Desai reports consulting, speaking and/or being a shareholder for and receiving research grants and stipends from Glaukos, LayerBio and SpyGlass Pharma.

Edited by Miriam Kaplan, PhD

Sources:

Michela Cimberle, Healio Ocular Surgery News, June 27, 2024; see source article

Michela Cimberle, Healio Ocular Surgery News, August 25, 2023; see source article