Allergan has continued its recent mega spending spree snapping up exclusive global rights to a migraine programme in development at Merck & Co.

The Irish group said it is paying $250 million upfront for access to Merck's experimental oral calcitonin gene-related peptide (CGRP) receptor antagonists, just a day after announcing its purchase of eye disease gene therapy group Oculeve. 

MK-1602 is being developed for the acute treatment of migraines and is due to be tested in Phase III in 2016. MK-8031 is destined for the prevention of migraines, for which a Phase II study is also due to start next year.

Under the deal, Allergan takes full responsibility for development of the CGRP programs, as well as manufacturing and commercialisation upon approval and launch of the products. Merck stands to bag development and commercial milestone payments and tiered double-digit royalties based on commercialisation of the programs.

Migraine affects around 36 million people in the US.