By Lisa Seachrist
Following promising Phase II results from two separate clinical trials, CoCensys, Inc., has decided to develop its lead drug candidate, ganaxolone, for the treatment of epilepsy and migraine.
In making the decision to proceed, the Irvine, Calif., company also has begun looking for development partners to complete clinical development and market ganaxolone, should it ultimately gain FDA approval.
"We are extremely pleased to find this efficacy with a less than optimal formulation," said Joann Data, senior vice president of clinical development and regulatory affairs at CoCensys. "These studies demonstrate a proof of concept for this new class of compounds."
Ganaxolone is a synthetic version of the naturally occurring neuroactive steroids called epalons. These molecules bind to specific sites on the GABA-A (gamma-aminobutyric acid) receptor complex in the brain and have a calming effect on neurological activity in the brain.
The company tested ganaxolone in 52 epilepsy patients who no longer responded to antiseizure medications and were suffering from such debilitating seizures they were scheduled for surgery to remove the portion of their brains that was instigating the seizures.
The patients were taken off all antiseizure medications and ganaxolone was given to them during the period prior to their surgeries. Each participant was given an oral suspension of either ganaxolone or placebo for up to eight days or until a predefined seizure frequency or type caused them to drop out of the study. Patients receiving placebo were twice as likely to suffer a seizure as compared to those on ganaxolone.
Following animal studies that showed naturally occurring epalons also could relieve migraines, CoCensys decided to test ganaxolone in 252 women who suffer migraine headaches.
The women were divided into five groups that received either one of four doses of ganaxolone or a placebo. The company found that patients who achieved drug levels in their blood of 80 nanograms per milliliter or more were more likely to begin experiencing pain relief in two hours and more likely to achieve complete pain relief in four hours than women who had a lower concentration of the drug in their bloodstreams.
Data said the company still is analyzing the findings from the two trials, and they need to conduct toxicology and carcinogenesis studies on the compound as well as developing a better formulation.
"Ganaxolone represents a potentially breakthrough class of compounds to treat diseases that are just waiting for new options," Data said.
CoCensys has a partnership with G.D. Searle & Co., of Skokie, Ill., to develop an epalon for insomnia and a deal with the Wyeth-Ayerst division of American Home Products Corp., of Madison, N.J., to develop an epalon for the treatment of anxiety. Searle is a subsidiary of St. Louis-based Monsanto Co.
CoCensys' stock (NASDAQ:COCN) closed Friday at $4.64, down $0.61. *