QLT Inc announced encouraging interim data from an ongoing Phase II clinical trial and a device study for the punctal plug delivery system. These studies are part of a development program that is being conducted by QLT’s wholly-owned subsidiary, QLT Plug Delivery, Inc.
Preliminary interim results from the ongoing Phase II clinical trial of the 44-µg Latanoprost Punctal Plug Delivery System (L-PPDS) show that the mean change in intraocular pressure (IOP) from baseline was -3.5 mmHg at the Week 4 visit with 36% of patients having an IOP decrease from baseline =5 mmHg. The 44-µg L-PPDS employs an early, proprietary punctal plug prototype, and based on a review of the preliminary data, it was well tolerated.
These results from the ongoing Phase II clinical trial evaluating the safety, efficacy, and dosing of the L-PPDS for the treatment of open angle glaucoma (OAG) and ocular hypertension (OH) are based on IOP data from 47 patients treated with the 44-µg L-PPDS for four weeks. The objective of this trial is to evaluate two doses of latanoprost (44 µg and 81 µg) to contribute data to identify the most promising formulations for a Phase II dose-ranging and a subsequent Phase III registration trial. Subjects are currently enrolling to receive the 81-µg dose formulation, and the Company plans to initiate clinical evaluations of two to three additional higher dose formulations later this year. The goal of these studies is to identify novel formulations that achieve a =5 mmHg drop in mean IOP.
The 44-µg L-PPDS is roughly equivalent to 29 latanoprost eye drops, or about one-third the amount of drug in eye drops given continuously over three months. The 81-µg L-PPDS is roughly equivalent to 54 latanoprost eye drops, or about 60% of the amount of drug in eye drops given continuously over three months.
Concurrent with the Phase II clinical trial, punctal plug prototype designs for the sustained delivery system are being tested in an ongoing multicenter study in more than 500 healthy volunteers. Safety, tolerability, comfort, ease of handling and insertion/removal, and retention are being assessed in this study. The overall goal for development is to achieve 90% retention for 90 days. Based on currently available data, preliminary results for one family of designs show an overall retention rate of 75% after eight weeks of follow-up. While this does not yet meet the Company’s retention criteria, designs are continuing to be refined and evaluated, with longer-term follow-up on the improved designs anticipated by year-end.
“We are pleased with the progress of our Phase II clinical trial and device program,” said Bob Butchofsky, President and Chief Executive Officer of QLT. “The interim data we announced are encouraging and are in line with the data we reported from our earlier CORE study. The results observed at Week 4 are clinically meaningful and similar to the IOP decrease we saw in the CORE study at the same time point. We believe there is sufficient room to increase the dose of latanoprost to further increase reduction in IOP while maintaining a favorable safety profile, and we look forward to updating you on the clinical progress of our higher dose evaluations. We continue to refine our designs for punctal plugs and anticipate that these will lead to improved retention rates in ongoing clinical trials.”