After seven months of bids, bluster and lawsuits, hedge fund manager William Ackman and Valeant Pharmaceuticals appear to be giving up their pursuit of Allergan, the maker of Botox, as another big drugmaker has trumped their hostile bid.

Allergan agreed on Monday to be acquired for $66 billion by Actavis in a deal worth $219 a share in cash and stock. The deal would be the biggest ever for Actavis and the largest acquisition in a year full of big deals, eclipsing Comcast’s $45 billion takeover of Time Warner Cable and AT&T’s $48.5 billion purchase of DirecTV. It would be the third-largest health care deal ever in the United States, according to Standard & Poor’s Capital IQ.

The deal capitalizes on a previous inversion deal by Actavis and presents a monumental roadblock for Valeant and Ackman, the unlikely consortium that teamed up in April to start what became the hostile campaign for Allergan.

In a statement after the announcement of the Actavis deal, Valeant’s chief executive, J. Michael Pearson, said, “While we will review any such agreement in determining our course of action, Valeant cannot justify to its own shareholders paying a price of $219 or more per share for Allergan.”