Aqueous Humor Concentrations of Travoprost Free Acid and Residual Drug in Explanted Implants from Patients...

To determine the aqueous humor (AH) exposure to travoprost free acid (TFA) and the in vivo elution rate of travoprost over a 24-month period in subjects with open-angle glaucoma administered a travoprost intracameral implant, 75 µg.

In this prospective, single-center, open-label study, 210 subjects (7 cohorts of 30 subjects each) were administered a travoprost intracameral implant and followed for 3-24 months. At pre-determined timepoints (3, 6, 12, 15, 18, 21, and 24 months), AH was collected, a new implant was administered, and the prior implant removed. AH samples were assayed for TFA concentrations using a validated liquid chromatography-tandem mass spectrometry method. Explants were analyzed for remaining travoprost using a validated high-performance liquid chromatography method.

Mean AH concentrations of TFA were 5.0, 3.7, 5.6, 2.0, 2.2, 3.8, and 3.3 ng/mL at 3, 6, 12, 15, 18, 21, and 24 months, respectively, post-administration. Mean percent travoprost remaining in explants was approximately 79%, 70%, 50%, 39%, 35%, 28%, and 16% at 3, 6, 12, 15, 18, 21 and 24 months, respectively, post-administration.

Concentrations of TFA in AH through month 24 were above the established efficacious concentration of 0.1 ng/mL for intracameral implants, indicating that adequate TFA levels were achieved to elicit maximal intraocular pressure (IOP)-lowering efficacy, and supported by low levels of IOP in subjects through 24 months. The remaining dose of travoprost in explants at 24 months (i.e., 16%) indicates the potential for efficacious drug delivery beyond 2 years.

Clinical Trials.gov Identifier: NCT06582732 (31 August 2024: retrospectively registered).