CollaGenex Pharmaceuticals has entered into a definitive merger agreement with an affiliate of Galderma Pharma pursuant to which Galderma’s US holding company, Galderma Laboratories, Inc., will acquire all of the outstanding shares of CollaGenex at a price of $16.60 per share in cash, representing approximately $420 million for the equity of CollaGenex. The transaction was unanimously approved by the boards of directors of CollaGenex and Galderma.