Achillion Pharmaceuticals, Inc. is a biopharmaceutical company focused on the discovery, development and commercialization of treatments for infectious diseases. The Company is engaged in the development of antivirals for the treatment of chronic hepatitis C infection (HCV), and the development of antibacterials for the treatment of resistant bacterial infections. The Company focuses on the development of four drug candidates for the treatment of HCV: ACH-1625, a NS3 protease inhibitor for the treatment of HCV, which is being tested in a phase IIa clinical trial, ACH-2684, a NS3 protease inhibitor for the treatment of HCV, which is being tested in a phase I clinical trial; ACH-2928, a NS5A inhibitor for the treatment of HCV, which is being tested in a phase I clinical trial, and ACH-3102, a NS5A inhibitor for the treatment of HCV, which is being prepared for investigational new drug (IND), filing and initiation of a phase I clinical trial.