Glaukos announced that its iDose TR sustained-release travoprost implant continued to provide sustained substantial reductions in IOP in a 24-month interim analysis of the ongoing 36-month phase 2b clinical trial conducted under a U.S. investigational new drug (IND) protocol.
Administered during a micro-invasive procedure, the iDose TR contains a novel formulation of travoprost, a prostaglandin analog used to reduce IOP, and was designed to continuously release therapeutic levels of the medication for at least 1 year. Once all travoprost is released, the iDose TR was designed to be removed and replaced with a new iDose TR, thus offering an alternative to daily eye drop treatment.
The 154-subject, multicenter, randomized, double-blind phase 2b trial was designed to evaluate a single administration of one of two iDose TR models with different travoprost release rates compared to topical timolol ophthalmic solution, 0.5% BID (twice a day). The primary efficacy endpoint agreed on with the FDA is the noninferiority comparison to timolol over the first three months after a single implantation of iDose TR. The currently reported phase 2b results are based on an interim analysis conducted at 24 months for all 154 subjects randomized into the trial, with 51, 54 and 49 subjects randomized to iDose TR fast-release arm, iDose TR slow-release arm and timolol active comparator arm, respectively. All IOP analyses were calculated using all IOP observations over 24 months weighted equally with no imputations for protocol-mandated medications. The subjects randomized to either iDose TR arm received a single intracameral implant while the subjects randomized to the timolol active comparator received twice-daily eye drops over the 24-month evaluation period, which equates to approximately 1,460 eye drops per eye, per protocol.
Topline summary results and observations from the interim analysis of the iDose TR phase 2b clinical trial at 24 months are as follows:
- Average IOP reductions from baseline observed during the first 24 months were 7.9 mmHg and 7.4 mmHg in the fast- and slow-release iDose TR arms, respectively, versus 7.8 mmHg in the timolol control arm.
- Average IOP reductions from baseline observed during the first 24 months were 29% and 28% in the fast- and slow-release iDose TR arms, respectively, versus 30% in the timolol control arm.
- Over the first 24 months, 23% and 20% of subjects in the fast- and slow-release iDose TR arms reported average IOP reductions from baseline of at least 40%, respectively, versus 13% in the timolol control arm.
- Subjects who had been on a single pre-study IOP-lowering medication at the screening visit had greater average IOP reduction over 24 months on iDose TR versus the pre-study IOP-lowering eye drops.
- The iDose TR arms progressed at a similar number of protocol-mandated medications compared to the timolol control arm, with all arms requiring an average of less than one medication added through two years.
- The 24-month phase 2 data also continued to demonstrate a favorable safety profile for iDose TR, with no clinically significant corneal endothelial cell loss, no serious corneal adverse events and no adverse events of conjunctival hyperemia reported to date in either elution arm.
“These latest phase 2 results further underscore the potential of iDose TR to safely provide multiple years of sustained glaucoma pharmaceutical therapy and tackle the significant problem of patient non-adherence to topical glaucoma medication regimens,” Thomas Burns, Glaukos president and chief executive officer, said in a company news release. “We believe there is an important unmet clinical need and strong appetite within the ophthalmic community for safe, effective and durable sustained-release pharmaceutical alternatives to traditional topical medications. These data reaffirm our excitement about the potential commercial prospects of iDose TR. Our near-term focus remains on completing enrollment in our ongoing iDose TR Phase 3 clinical program, which will mark another critical step forward in the advancement of our novel and comprehensive product pipeline designed to transform glaucoma therapy.”
Glaukos continues to progress toward enrollment completion in its ongoing phase 3 clinical program for iDose TR despite the ongoing impact of the COVID-19 pandemic on enrollment. The phase 3 program consists of two prospective, randomized, double-masked clinical trials designed to compare the safety and efficacy of iDose TR to topical timolol ophthalmic solution, 0.5%, in reducing elevated IOP in subjects with open-angle glaucoma (OAG) or ocular hypertension. The primary efficacy endpoint of the phase 3 studies is noninferiority comparison to topical timolol 0.5% BID over the first 3 months, and safety evaluations for up to 12 months. The phase 3 trials are expected to randomize a total of approximately 1,100 subjects across approximately 100 clinical sites, the majority of which are in the United States. The 12-month iDose TR phase 3 trial results are expected to support Glaukos’ NDA submission in 2022 and the company is now targeting FDA approval for iDose TR in 2023.