UK-based AstraZeneca has entered an agreement with German pharmaceutical company Grünenthal to divest the global rights to Zomig (zolmitriptan) outside Japan.

Zomig is used for the acute treatment of patients suffering from migraine or cluster headaches in the EU. The therapy is currently available as an oral tablet, an orally dispersible tablet, and a nasal spray.

AstraZeneca's global product and portfolio strategy executive vice-president Mark Mallon said: “Grünenthal is an established partner with expertise in the treatment of pain. It is well placed to ensure patients continue to benefit from Zomig and to extend the commercial potential of the medicine through its dedicated salesforce.”

Upon completion of the transaction, Grünenthal Group will pay $200m to AstraZeneca, which will also receive up to an additional $102m in future milestone payments. Grünenthal will receive the rights to the migraine treatment in all markets outside Japan, including the US, where the rights were previously licenced to Impax Pharmaceuticals.

"Migraine is a very debilitating disease with more than 75 million people worldwide suffering from attacks that can lead to sensitivity to light or sound, to nausea or even vomiting."

Grünenthal's chief executive officer (CEO) Gabriel Baertschi said: “Migraine is a very debilitating disease with more than 75 million people worldwide suffering from attacks that can lead to sensitivity to light or sound, to nausea or even vomiting.

“The acquisition of the well-established Zomig products complements our existing pain portfolio.”

Impax Pharmaceuticals will continue to market Zomig in the US, while AstraZeneca will continue to produce and supply the medicine to Grünenthal during a transition period.

Subject to customary conditions and regulatory clearances, the transaction is expected to close in Q2, 2017.