Olopatadine punctal plug trial halted

Vancouver, British Columbia-QLT Inc. has halted a randomized, placebo-controlled, double-masked phase II proof-of-concept trial of an olopatadine (Patanol, Alcon) punctal plug delivery system (O-PPDS) after the study model “could not generate definitive clinical results,” according to company officials.

Interim results demonstrated that the O-PPDS generally was safe and well-tolerated in patients with allergic conjunctivitis. No significant differences were noted between patients receiving the O-PPDS and those receiving a placebo PPDS with respect to reduction in the signs and symptoms of allergic conjunctivitis. Both cohorts saw similar improvements. Internal study controls, including the olopatadine and placebo eye-drop cohort responses, also did not 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 environmental exposure chamber model, as utilized in the conduct of this trial, was not sufficiently sensitive to demonstrate the potential benefit of the O-PPDS adequately in patients suffering from allergic conjunctivitis,” said Dipak Panigrahi, MD, senior vice president of research and development and chief medical officer of QLT. “Given these findings, we have decided to stop the current study.”

Bob Butchofsky, president and chief executive officer of QLT, said, “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. We do not plan to begin further clinical trials of the O-PPDS pending the outcome of our ongoing latanoprost (Xalatan, Pfizer) PPDS trial in glaucoma.”