QLT Announces Phase II Clinical Trial Results For The Olopatadine Punctal Plug Delivery System (O-PPDS)

VANCOUVER, British Columbia, Feb. 9, 2011 (GLOBE NEWSWIRE) -- QLT Inc. (Nasdaq:QLTI) (TSX:QLT) ("QLT" or the "Company") today announced results from a Phase II proof-of-concept clinical trial for the olopatadine punctal plug delivery system (O‑PPDS).

Interim results from the randomized, placebo-controlled, double-masked Phase II proof-of-concept trial have shown that O-PPDS is generally safe and well tolerated in subjects with allergic conjunctivitis. An analysis has been performed on data from subjects in Group 1 of the study, in which the PPDS (O-PPDS or placebo-PPDS) was placed in subjects' lower puncta bilaterally for 4 days. Subjects were then exposed to ragweed allergen for 4 hours in an environmental exposure chamber (EEC). Itching and other signs and symptoms of allergic conjunctivitis were assessed during the 4-hour EEC session. Following a twelve-day washout period, the subjects were then assessed during an EEC session after treatment with Patanol® (commercially available olopatadine eye drops) or placebo eye drops.

The data demonstrate that there were no significant differences noted between the O-PPDS and placebo‑PPDS subjects with respect to reduction in the signs and symptoms of allergic conjunctivitis with both cohorts showing similar improvements. Internal study controls, including the olopatadine (Patanol®) and placebo eye drop cohort responses, also failed to confirm the model's efficacy relative to the trial design.

"These equivocal results from the first trial examining the potential utility of sustained low dose olopatadine delivery in the eye support the notion that the EEC model, as utilized in the conduct of this trial, was not sufficiently sensitive to adequately demonstrate the potential benefit of the O‑PPDS in patients suffering from allergic conjunctivitis," said Dipak Panigrahi, MD, Senior Vice President, Research and Development and Chief Medical Officer of QLT. "Given these findings, we have decided to stop the current study at this time." 

"We are disappointed that the O-PPDS study model could not generate definitive clinical results, however we plan to continue to evaluate alternative study designs for the O-PPDS," said Bob Butchofsky, President and Chief Executive Officer of QLT. "We do not plan to begin further clinical trials of the O-PPDS pending the outcome of our ongoing Latanoprost-PPDS trial in glaucoma."