Pfizer circles Botox-maker Allergan for possible $300 billion merger

Drugmaking giant Pfizer is on the prowl again and has Botox-maker Allergan in its sights, in what could become the biggest merger in a bumper year for deals.

Pfizer, which makes blockbuster drugs Lipitor and Viagra, has recently approached Dublin-based Allergan about combining to create a $300 billion (£196 billion) firm.

The move follows Pfizer’s failed hostile attempt to buy Britain’s AstraZeneca for £69.4 billion last year.

A deal with Allergan, which is valued at about £74 billion, could offer some of what Pfizer missed out on in the collapse of the AstraZeneca deal — a way to cut its tax bill by switching its headquarters to a lower tax regime.

It would also strengthen Pfizer’s stable of patent-protected drugs.