FDA rejects a new epilepsy drug from Valeant, GSK

The FDA has rejected a new epilepsy drug from Valeant Pharmaceuticals ($VRX) and GlaxoSmithKline ($GSK), saying that the drug companies have to meet some "non-clinical" demands from regulators for further information. But anyone trying to glean what the regulatory issues are would find little insight from their terse release.

The companies' only comment on the rejection of ezogabine is outlined in a short release noting that the companies believe they can address these items and "are working for a timely response to the FDA as soon as possible in 2011." There are close to three million people in the U.S. who suffer from epilepsy, and the therapy is designed to treat a large subset whose seizures can't be controlled with currently available drugs. It's potentially a big market, which analysts have estimated is worth anywhere from $200 million to more than $800 million in peak annual sales.

GSK was staying tight-lipped on the rejection and a Valeant spokesperson would only tell Bloomberg that the complete response letter from the agency included "some end-of-approval type requirements."

The FDA had already delayed its decision on the drug once. But with unanimous votes from the expert advisory panel on efficacy--in combination with currently approved drugs--and a manageable side effect profile, the companies may well be on their way to a 2011 approval. Investors, left with little real insight into the cause of this latest delay, largely remained on the sidelines as Valeant's shares slipped about three percent on the news.

- here's the Valeant release
- read the Bloomberg story
- see the Reuters report