SALEM, Mass.--(BUSINESS WIRE)--Commonwealth Laboratories, Inc. ("Commonwealth") announced today that it has reached an agreement with Valeant Pharmaceuticals International, Inc. ("Valeant") for the acquisition by Valeant of Commonwealth's business in the United States (U.S.) and Canada. This includes rights to IBSchek , a breakthrough blood test designed to help physicians quickly and reliably diagnose irritable bowel syndrome (IBS). Commonwealth's existing management team will remain in place