Glaxo, Valeant Epilepsy Drug Wins U.S. Backing as Add-On

GlaxoSmithKline Plc (GSK) and Valeant Pharmaceuticals International Inc. (VRX) won U.S. approval for an epilepsy drug designed as an add-on therapy for patients who aren’t helped by current treatments.

The Food and Drug Administration cleared the medicine, chemically known as ezogabine, the companies said today in a statement. The FDA delayed a decision on the product, to be marketed as Potiga, twice last year.

More than 2 million people in the U.S. have been diagnosed with epilepsy or suffered from an unprovoked seizure, according to the National Institute of Neurological Disorders and Stroke. London-based Glaxo and Valeant estimate that a third of patients can’t control seizures with current epilepsy medicines, leading to disability and an unsatisfactory quality of life.

“We are so pleased to reach such an important milestone with the U.S. approval of Potiga by the FDA,” said Susan Hall, Valeant’s head of research and development. “This product will play a needed role in the management of partial onset seizures in appropriate patients who are uncontrolled on their current medications.”

Glaxo, the U.K.’s biggest drugmaker, bought global marketing rights to ezogabine from Valeant in 2008. The medicine acts on the brain’s potassium channel, controlling nerve cells so they don’t become over-stimulated and cause a seizure. Most current drugs regulate sodium or calcium channels.

Controlled Substance

Valeant, based in Mississauga, Ontario, fell 97 cents, or 1.8 percent, to close at $52.83 in New York Stock Exchange composite trading on June 10. Glaxo shares fell 4 pence, or 0.3 percent, to 1,272.5 pence at 8:10 a.m. in London. Meda AB (MEDAA), of Solna, Sweden, which discovered the drug and is entitled to royalties, climbed 1.30 kronor, or 2 percent, to 67.30 kronor.

The FDA recommended that ezogabine be considered a controlled substance, so the U.S. Drug Enforcement Administration is reviewing how the drug should be classified, the companies said. Ezogabine won’t be available until that process is finished, though it should be in pharmacies by the end of the year, according to the statement.

An FDA advisory panel recommended in August that ezogabine worked as an add-on treatment and that bladder blockage, a side effect seen in studies, could be controlled by monitoring patients. The medicine won the backing of a European Union regulatory panel in January.

Ezogabine may bring in sales of $235 million for Glaxo in 2015, according to the average estimate of four analysts surveyed by Bloomberg. One analyst projected $40 million in revenue for Valeant that year. The drug is known as retigabine outside the U.S.

To contact the reporter on this story: Catherine Larkin in Washington at

To contact the editor responsible for this story: Adriel Bettelheim at

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