Allergan Asked for More Evidence on Botox for Migraines by U.K. Agency

Allergan Inc. (AGN) needs to provide more information on its wrinkle-smoother Botox as a treatment for chronic migraine headaches, the U.K.’s health-cost agency said.

More information is needed because the benefit demonstrated by clinical trials is small and the results may have been biased, the National Institute for Health and Clinical Excellence said in a statement today. Trial participants may have known they were getting Botox rather than a placebo because of the muscle paralysis it causes, the agency said.

“Without this additional evidence, potentially we will be unable to advise the National Health Service that this drug is good value for money,” Carole Longson, director of NICE’s Health Technology Evaluation Centre, said in the statement.

Allergan of Irvine, California won U.S. regulatory approval to sell Botox for chronic migraine headaches in October, which may help almost double the drug’s annual sales to $2.3 billion, according to Sanford C. Bernstein & Co. The drug, a purified form of the poison botulinum, is given as an injection. It was cleared for those who have migraines at least 15 days a month and whose pain lasts at least four hours.

NICE will accept comments through March 8 and will issue final guidance in June, it said.

To contact the reporters on this story: Makiko Kitamura in London at

To contact the editor responsible for this story: Phil Serafino at

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