Tomas Navratil

Credit: Glaukos Corporation

A travoprost intraocular implant may effectively lower intraocular pressure (IOP) over the course of 36 months after a single administration, according to new findings, substantially diminishing the necessity of topical IOP-lowering medications and helping to lessen problems with adherence and side effects.¹

These findings on the implant’s sustained-release drug delivery system were the results of a phase 2 trial conducted to look at the long-term safety and the effectiveness of travoprost intraocular implant. The investigators noted prior to their research that IOP is the only known modifiable risk factor for glaucoma, with many studies pointing to the essential role of IOP lowering in the practice of decreasing glaucoma development.²

The overall goal of the investigators was to find a way to reduce treatment burden for patients and to improve adherence to IOP-lowering treatments, and this particular system was assessed in this analysis. The research into this implant for IOP was authored by Tomas Navratil, from the Glaukos Corporation in Aliso Viejo, California.

“The objective of the current study was to report on the 3 year safety of the implant, and percentage of patients who reduced or maintained their topical IOP-lowering medication burden relative to pre-study medications,” Navratil and colleagues wrote.

Background and Findings

The travoprost intraocular implant, a minute titanium container measuring 1.84 mm—including its anchor—by 0.494 mm in outer diameter. The implant releases travoprost through the use of a thin membrane, held by a titanium cap and preloaded into a single-use inserter for internal advancement by the patient’s surgeon into the anterior chamber, anchoring the device in the sclera.

The investigators implemented a phase 2 clinical trial, carrying out their research from March 2016 - July 2020. They involved 154 total subjects in the age 18 and older bracket, with these individuals having diagnoses of open-angle glaucoma (OAG) or ocular hypertension (OHT).

The trial’s design was prospective, randomized, double-blinded, and placebo-controlled, and the research team conducted their analysis at 23 sites found in the US and a single site in the Philippines.

The team sought to examine the safety and efficacy of 2 travoprost intraocular implants that each used different elution rates compared to timolol eye drops (Timolol Maleate Ophthalmic Solution, USP, 0.5%) for those with OAG or OHT who were already on 0–3 topical medications that were IOP-lowering.

Individuals who had been diagnosed with open-angle glaucoma or with ocular hypertension were assigned to be placed into 1 of 3 groups:

• A fast-eluting implant (FE implant, n = 51) and twice-daily (BID) placebo eye drops
• A slow-eluting implant (SE implant, n = 54) and BID placebo eye drops
• A sham surgical procedure with BID timolol 0.5% (n = 49)

IOP measurements were done at several different intervals up to 36 months. The investigators looked at efficacy by assessing the mean change from the 8:00 AM unmedicated baseline IOP throughout the total study period.

The research team also looked into the percentage of subjects using the same or fewer topical IOP-lowering treatments as they had at screening. They evaluated safety data by monitoring the reported adverse events and using different ophthalmic parameters.

The intraocular implant was shown to have strong efficacy in its reduction of IOP, with the investigators finding major decreases in subjects’ need for topical medications designed for IOP-lowering. This decrease lasted for a duration of up to 36 months following a single administration.

“These results suggest that the travoprost intraocular implant may represent a meaningful addition to the interventional glaucoma armamentarium, demonstrating safe and well-tolerated IOP lowering for up to 36 months after a single administration and addressing the key shortcomings of topical IOP-lowering medications defined by low adherence and adverse impact on ocular surface health,” they wrote.

References

1. ^{Berdahl, J.P., Sarkisian, S.R., Ang, R.E. et al. Efficacy and Safety of the Travoprost Intraocular Implant in Reducing Topical IOP-Lowering Medication Burden in Patients with Open-Angle Glaucoma or Ocular Hypertension. Drugs (2023). https://doi.org/10.1007/s40265-023-01973-7.}
2. ^{Gordon MO, Beiser JA, Brandt JD, et al. The Ocular Hypertension Treatment Study: baseline factors that predict the onset of primary open-angle glaucoma. Arch Ophthalmol. 2002;120(6):714–20. https://doi.org/10.1001/archopht.120.6.714.}