Ocular insert lowers IOP for 13 months

An extended release bimatoprost ocular insert successfully lowered intraocular pressure in open-angle glaucoma patients for 13 months without additional IOP-lowering eye drops, James D Brandt MD told Glaucoma Day at the 2016 American Society of Cataract and Refractive Surgery Symposium in New Orleans, USA. The phase 2 clinical trial, published online this week in Ophthalmology, is the first to demonstrate the promise of extended release devices to replace eye drops over such a long time.

The non-biosorbable ring of a bimatoprost-polymer matrix is 24mm to 29mm in diameter. Inserted under the eyelid, it elutes preservative-free bimatoprost at a therapeutic level for about six months, said Dr Brandt, of the University of California-Davis, USA.

In a six month trial, 63 patients treated with the bimatoprost ring and artificial tears twice daily saw mean IOP drop nearly as much as 64 patients treated with timolol 0.5 per cent twice daily and a non-medicated insert. In a seven month open-label single-arm extension, patients received a second insert and maintained IOP reductions of 4-6mmHg for the entire 13 months. Adverse events were similar to those seen with bimatoprost eye drops and mostly resolved without complications, Dr Brandt reported. A third insert was then placed, which will extend the ongoing study to 19 months.

The ring inserts are larger than punctal plugs which gives them a greater medication reservoir and makes them less likely to fall out unnoticed, Dr Brandt said. They can be re-inserted if they do dislodge, can be inserted by most eye care providers and can easily be removed if necessary. Nearly 90 per cent of patients retained the ring without assistance for the first six months, and 97 per cent for the second cycle of seven months.

The manufacturer, ForSight Vision5, has received guidance from the US FDA on a trial design needed to bring the ring to market, Dr Brandt said. The phase 3 program is planned for later this year.