DRUG-DELIVERY SYSTEMS COULD HELP SOLVE PATIENT NONADHERENCE ISSUES

MANY GLAUCOMA patients say they always take their drops. But the data tell a different story. For example, a 2009 Ophthalmology study reveals that nearly 45% of patients used their drops less than 75% of the time, even though they received free drops and knew their drop use was being monitored.

Intraocular drug delivery systems, now in clinical trials, and discussed here, could solve the patient nonadherence issue.

BIMATOPROST SR

This biodegradable sustained-release intracameral implant (Allergan) releases bimatoprost consistently through a six-month period. The implant resides in the anterior chamber and is currently in Phase 1, 2 and 3 clinical trials.

After 75 patients had a 6 ug, 10 ug, 15 ug or 20 ug bimatoprost pellet placed in one eye and had received daily topical bimatoprost 0.03% in the other eye for 16 weeks, IOP reduction ranged from 7.2 mmHg to 9.5 mmHg in the implant group, compared with 8.4 mmHg in the topical group, reports the American Journal of Ophthalmology. Further, the IOP reduction was sustained in 71% of these patients through six months.

In addition, 66.7% and 23.8% of 21 patients in a Phase 1 and 2 clinical trial receiving a 10 ug or a 15 ug bimatoprost pellet had their IOP controlled for up to six months and 24 months, respectively, reports a paper presented at the 2018 American Glaucoma Society meeting. It is possible that the sustained-release implant could provide longer IOP reduction and control than initially thought.

Adverse events: mild conjunctival hyperemia

iDOSE

This 1.8 mm x 0.5 mm titanium implant (Glaukos) is placed in the eye’s anatomical angle through a clear corneal incision and allows for the controlled elution of travoprost into the anterior chamber, via a capped membrane.

A Phase 2 randomized clinical trial is ongoing comparing two different elution rates to topical timolol maleate 0.5%. Thus far, 12-month efficacy results reveal average IOP reductions from baseline through 12 months ranging from 7.9 mmHg to 8.5 mmHg in the implant groups. This represents a 32% to 33% reduction in the implant groups. Also, both implant groups are showing greater IOP reductions than the timolol 0.5% group.

Adverse events: none

ENV515

This biodegradable nanotechnology polymer intracameral drug-delivery system (Aerie) releases travoprost in the anterior chamber for six months.

Five patients achieved about 7 mmHg (25%) IOP-lowering effects from their washout baseline IOPs of 26.1 mmHG at 11 months, reveals a 12-month Phase 2a clinical trial. (The patients, with 19.7 mmHg entering IOPs, took either bimatoprost ophthalmic solution 0.01% (Lumigan, Allergan) or latanoprost ophthalmic solution 0.005% (Xalatan, Pfizer).)

Adverse events: early onset transient hyperemia related to the dosing procedure OM

DR. SCHWEITZER specializes in advanced glaucoma, refractive surgical clinical care and anterior segment pathology at Vance Thompson Vision. He has had multiple articles published and has delivered lectures on glaucoma, anterior segment pathology, refractive surgical clinical care and surgical management. Email him at justin.schweitzer@vancethompsonvision.com.