Allergan Inc. has entered into a long-term agreement with GlaxoSmithKline (GSK) to develop and promote Allergan's Botox (botulinum toxin type A) in Japan and China and to co-promote GSK's products Imitrex Statdose System (sumatriptan succinate) and Amerge (naratriptan hydrochloride) in the United States.

Under the terms of the agreement, Allergan will license to GSK all clinical development and commercial rights to Botox in Japan and China, markets in which GSK has extensive commercial, regulatory and R&D resources, as well as expertise in neurology, informs a company release.

In addition, Allergan has obtained the right to co-promote GSK's products Imitrex Statdose System and Amerge in the US to neurologists for a 5-year period.

Botox has treated millions of patients with serious or debilitating disorders as well as cosmetic needs, added the release.

Imitrex Statdose System is approved for the treatment of acute migraine in adults and for the acute treatment of cluster headache episodes. Amerge tablets are approved for the acute treatment of migraine attacks with and without an aura in adults.