UK for J&J's epilepsy drug Topamax in migraine

The US Food and Drug Administration has approved Johnson & Johnson'sepilepsy drug Topamax (topiramate) in tablet and sprinkle capsule form for the prophylaxis of migraine headaches in adults.

For its existing indication of epilepsy, Topamax achieved sales of over $1 billion in 2003. The new approval is not expected to add significantly to the drug's turnover as it is already being used off-label for migraine prevention; analyst Bruce Cranna at Leerink Swann believes additional annual sales will be only around $100 million, reports Reuters.

In clinical studies with Topamax, many people with migraines experienced significantly fewer attacks, enabling them to help manage their condition, says J&J. Clinical trials found that patients receiving the recommended daily dose of the drug experienced a significant reduction in monthly migraine attacks compared with placebo. In one study, a 100mg-200mg daily dose reduced the frequency of migraines by 2.1-2.4 days per month.