TORREYPINES INITIATES STUDY OF AK RECEPTOR ANTAGONIST

TorreyPines Therapeutics has initiated a second Phase I clinical trial of NGX426, a novel product candidate intended to treat chronic pain conditions such as migraine and neuropathic pain. NGX426 is an oral prodrug of tezampanel, the company's parenteral product candidate currently in a Phase IIb clinical trial for acute migraine.

The double-blind, placebo-controlled, clinical trial will evaluate the safety, tolerability and pharmacokinetics of NGX426 to determine the maximum safe and well-tolerated oral dose. Approximately 60 healthy adult volunteers, enrolled in sequential, dose-escalating cohorts, will receive placebo or a single dose of NGX426. The trial is intended to evaluate doses of NGX426 ranging from 40 mg up to the maximum tolerated dose. In a previous Phase I trial, completed in November 2006, NGX426 was well tolerated at doses up to 30 mg, and pharmacokinetic analyses confirmed that it was rapidly converted to tezampanel.

Tezampanel and NGX426 are AMPA/kainate (AK) receptor antagonists that potentially offer a non-narcotic, nonvascular approach to the treatment of chronic pain, including migraine. As AK receptor antagonists, tezampanel and NGX426 may effectively relieve severe and persistent pain through a novel mechanism of action without imparting the side effects and risks associated with currently available treatment options for chronic pain. Five Phase IIa, double-blind, placebo-controlled trials have demonstrated that tezampanel, administered intravenously, was more effective than placebo in relieving pain symptoms across multiple pain models, according to the company.