Pfizer to Acquire Biohaven Pharma for $11.6 Billion in Cash, Sending Biohaven Shares up 71% Premarket

Pfizer Inc. said Tuesday it has entered a definitive agreement to acquire Biohaven Pharmaceutical Holding Company Ltd.  for $11.6 billion in cash.

Biohaven is the maker of NURTEC ODT, a dual-acting migraine therapy approved for both acute treatment and episodic prevention of migraine in adults. Under the terms of the deal, Pfizer will pay $148.50 for each Biohaven share, and shareholders will also receive 0.5 of a share of New Biohaven, a new publicly traded company that will retain Biohaven's non-calcitonin gene-related peptide, or CGRP, development stage pipeline compounds.

Pfizer will also make payments at closing -- expected by 2023 -- to settle Biohaven's third-party debt and to redeem preferred stock. The $148.50 cash consideration is equal to a 33% premium over Biohaven's volume weighted average selling price of $111.70 over the three months prior to the announcement of the transaction.

Biohaven shares immediately soared 71% premarket; the stock closed at $83.14 on Monday.

"Today's announcement builds on our legacy of delivering breakthroughs for patients living with complex pain disorders and diseases that disproportionately impact women," said Nick Lagunowich, global president, Pfizer internal medicine. Pfizer had already announced a collaboration with Biohaven and had invested $350 million to buy 2.6% of its common stock at $173 a share in November of 2021.