Valeant Starts CEO Search, Adds Bill Ackman to Board

Valeant Pharmaceuticals International Inc. said Monday that it has begun a search for a new chief executive to succeed J. Michael Pearson and named William Ackman to its board.

The moves come after Valeant shares plunged last week following the drugmaker's reduced earnings guidance, warning about a potential debt default and contentious call that turned off analysts and investors.

Mr. Pearson will continue to serve as CEO and a director until his replacement is appointed.

Write to Tess Stynes at tess.stynes@wsj.com