(Reuters] -Pfizer Inc stated Tuesday that it was buying Biohaven Pharmaceutical Company Ltd, a manufacturer of migraine drugs for approximately $11.6 billion.

Pfizer (NYSE:) will buy all outstanding Biohaven shares not owned by Pfizer at $148.50 per share cash. This is a 78.6% discount to Biohaven’s closing price.

Biohaven shareholders including Pfizer will receive 0.5 shares of a newly traded company. This new company will keep Biohaven’s non-migraine therapies that are still in development.

Pfizer purchased overseas rights for two Biohaven migraine medications in November. Pfizer also took a 2.6% equity share of the small company.