Pfizer secured formal board approval on Sunday for its acquisition of Botox maker Allergan for more than $150 billion, a deal that will create the world's biggest drug maker, according to people familiar with the matter.
The deal, the largest ever in the healthcare sector, will be announced on Monday and is sure to draw political ire in a U.S. presidential election year because Pfizer would redomicile to Ireland, where Allergan is registered, in a so-called "inversion" that would slash its corporate tax rate.
It will also reignite debate in the pharmaceutical industry over the role of research and development, with Allergan Chief Executive Brent Saunders, a prolific dealmaker and a skeptic of in-house drug discovery, joining the combined company in a position to influence its strategy.
The deal would involve Pfizer paying with 11.3 of its shares for each Allergan share, the people said. There will also be a small cash component, accounting for less than 10 percent of the value of the deal, the people said.
Pfizer's Chief Executive Ian Read, 62, will be CEO of the combined company, with Allergan's CEO Brent Saunders, 45, serving in a very senior role focused on operations and the integration, the people added.
Saunders will also have a seat on the combined company's board, one of the people said.
The sources asked not to be identified because the terms of the deal are not yet public. Pfizer and Allergan declined to comment.