Achillion is an innovative biopharmaceutical company dedicated to bringing important new treatments to patients with infectious disease. The Company's highly skilled and experienced discovery and development teams have advanced multiple product candidates with novel mechanisms of action. Achillion is focused on solutions for the most challenging problems in infectious disease - HCV, resistant bacterial infections, and HIV.

The Company's focus is currently on developing three clinical candidates for the treatment of chronic hepatitis C infection. First, Achillion is developing ACH-1625, a proprietary NS3 protease inhibitor currently in early-stage clinical development. Second, Achillion is developing ACH-1095, a candidate from a unique class of compounds called NS4A antagonists which have been demonstrated to be synergistic or additive with other inhibitors under development for HCV infection. Finally, Achillion is developing ACH-2684, a highly potent, pan-genotypic inhibitor of HCV NS3 protease with pico-molar potency.  Achillion is also developing ACH-702, its candidate for the treatment of serious, resistant bacterial infections.  Each of these programs was discovered through Achillion's own proprietary internal drug discovery efforts.

Achillion has also completed a 96-week Phase II clinical program for elvucitabine, a novel nucleoside analog currently being evaluated for the treatment of patients with HIV. Achillion believes that elvucitabine addresses several of the limitations of currently marketed therapies and is an ideal candidate for partnerships around combination preparations and/or geographic commercialization alliances.

Achillion sees significant competitive advantages in developing anti-infective drugs compared to developing drugs in other therapeutic areas. The emergence of drug resistance seen with current antiviral and antibacterial therapies creates a continuing need for new drugs, providing a large and growing potential business opportunity. In addition, development cycle times tend to be somewhat shorter in infectious disease than other therapeutic areas, and early drug development results tend to be more predictive of longer term results.