Irvine-based Allergan Inc. is in advanced talks to buy Salix Pharmaceuticals Ltd. after turning down a buyout offer from Actavis PLC, according to a report today in the Wall Street Journal.

The maker of Botox and other drugs is looking for a deal to thwart a hostile bid valued at around $50.1 billion from Canada-based Valeant Pharmaceuticals International Inc. and activist investor Bill Ackman’s Pershing Square Capital Management LP.

Allergan could announce an all-cash deal for Raleigh, N.C.-based Salix this week or early next, according to the report. The report also added that New Jersey-based Actavis is still interested in buying Allergan through a friendly deal and would keep Allergan’s research and development intact—something that Valeant has said it would cut.

Salix’s shares were up 10% in after-hours trading after closing down 3% to a market value of $10.2 billion. Allergan shares were up 1% in after-hours trading after closing down 1% to a market value of $49.3 billion.

Valeant closed down 1% to a market value of $39 billion.

See “View of Allergan as Buyer Revived” in this week’s edition of the Business Journal for more.