iDose TR Travoprost intracameral implant

 

Glaukos Corporation, the company which developed the iStent device, has announced the FDA approval of their single administration iDose TR travoprost intracameral implant.

The device is made from medical-grade titanium and measures 1.8 mm × 0.5 mm. It is implanted using a technique similar to many MIGS procedures. A gonioprism is used to identify the anterior chamber (AC) angle, a 2.2 mm incision is made in clear cornea, the AC is filled with a cohesive viscoelastic and the device is implanted through the trabecular meshwork and the back of the Schlemm’s canal directly into the scleral tissue. The device is held in place by a scleral anchor. After the end of the specified period, the device is replaced by a new one. According to some, the device can be used for 4-5 years.

The device has a membrane-bound reservoir of 75 mcg travoprost which diffuses continuously into the anterior chamber. There are two iDose TR models available, which have two different rates of drug elution (referred to as fast- and slow-release iDose TR models). This drug-delivery platform circumvents the patient compliance issue which plagues many glaucoma patients.

Contraindications:

iDose TR is contraindicated in patients with active or suspected ocular or periocular infections, patients with corneal endothelial cell dystrophy (e.g., Fuch’s Dystrophy, corneal guttatae), patients with prior corneal transplantation, or endothelial cell transplants (e.g., Descemet’s Stripping Automated Endothelial Keratoplasty [DSAEK]), patients with hypersensitivity to travoprost or to any other components of the product.

Warnings and Precautions:

iDose TR should be used with caution in patients with narrow angles or other angle abnormalities. Monitor patients routinely to confirm the location of the iDose TR at the site of administration. Increased pigmentation of the iris can occur. Iris pigmentation is likely to be permanent.

Adverse Reactions:

In controlled studies, the most common ocular adverse reactions reported in 2% to 6% of patients were increases in intraocular pressure, iritis, dry eye, visual field defects, eye pain, ocular hyperaemia, and reduced visual acuity.

Studies:

The FDA approval is based on results from two prospective, randomized, multicenter, double-masked, Phase 3 pivotal trials (GC-010 and GC-012) designed to compare the safety and efficacy of a single administration of one of two iDose TR models with different travoprost release rates (referred to as the fast- and slow-release iDose TR models, respectively) to topical timolol ophthalmic solution, 0.5% BID (twice a day), in reducing IOP in subjects with open-angle glaucoma or ocular hypertension. In total, the Phase 3 trials randomized 1,150 subjects across 89 clinical sites. The FDA approval and Phase 3 data referenced below is for the slow-release iDose TR model, consistent with the company’s NDA submission and commercialization plans.

Both Phase 3 trials successfully achieved the pre-specified primary efficacy endpoints through 3 months and demonstrated a favorable tolerability and safety profile through 12 months. IOP reductions from baseline over the first 3 months were 6.6-8.4 mmHg in the iDose TR arm, versus 6.5-7.7 mmHg in the timolol control arm.

 iDose TR demonstrated non-inferiority to timolol ophthalmic solution in IOP reduction during the first 3 months. The FDA also noted that subsequently iDose TR did not demonstrate non-inferiority over the next 9 months.

At 12 months, 81% of iDose TR subjects were completely free of IOP-lowering topical medications across both trials. In both trials, iDose TR demonstrated excellent tolerability and subject retention with 98% of iDose TR subjects continuing in the trial at 12 months, versus 95% of timolol control subjects. In controlled studies, the most common ocular adverse reactions reported in 2% to 6% of iDose TR patients were increases in intraocular pressure, iritis, dry eye, and visual field defects, most of which were mild and transient in nature.