First Approvals For Zeneca, Glaxo Wellcome Migraine Products

The migraine market has seen a phenomenal rate of growth over the lastfew years to become a billion dollar-plus market in 1996, stimulated mainly by the introduction of Glaxo Wellcome's Imigran/Imitrex (sumatriptan) in 1991, which revitalized the sector. And this trend looks set to continue with several new compounds coming to market.

In the latest development, Glaxo Wellcome has been granted its first approval, in Sweden, for naratriptan, a follow-up to sumatriptan which will be marketed as Naramig. In addition, Zeneca has gained approval in the UK for Zomig (zolmitriptan; formerly 311C90), the migraine drug it acquired last year from GW on antitrust grounds after the merger of Glaxo and Wellcome. Both drugs are registered for the acute treatment of migraine attacks, with or without aura.

Both the drugs are 5-HT1 receptor agonists and are said to offer activity distinct from the lead drug in this class, sumatriptan. Of particular importance, the two companies note, is naratriptan and zolmitriptan's ability to act centrally, within the brain, by constricting blood vessels, and also to act peripherally at the site of the trigeminal nucleus within the brain stem, which is thought to be a critical area in pain generation during a migraine. The recommended dose of both the drugs is one 2.5mg tablet per attack.