Hepatitis; U.S. Patent granted for ACH-1625 and Related Protease Inhibitors

Achillion Granted U.S. Patent for ACH-1625 and Related Protease Inhibitors


NEW HAVEN, Conn., — Achillion Pharmaceuticals, Inc. (Nasdaq:ACHN), a leader in the discovery and development of small molecule drugs to combat the most challenging infectious diseases, today announced that the U.S. Patent & Trademark Office has granted Achillion U.S. Patent No. 7,906,619, covering composition-of-matter and method of use claims for ACH-1625 and structurally related compounds. ACH-1625 is Achillion’s phase 2 protease inhibitor to treat hepatitis C virus (HCV) infection. This new patent, entitled “4-amino-4-oxobutanoyl peptides as inhibitors of viral replication,” provides a patent term until 2029.

“This key patent grant provides a cornerstone for Achillion’s intellectual property portfolio for ACH-1625 and a number of structurally related compounds, molecules that were discovered and synthesized here by Achillion’s discovery team,” commented Michael D. Kishbauch, Achillion’s President and Chief Executive Officer. “We believe this strengthening of our patent estate, combined with our expected upcoming pipeline milestones, including 4-week rapid viral response, or RVR, results from an ongoing phase 2 clinical trial of ACH-1625, and the advancement of ACH-2684 and ACH-2928 into phase 1 clinical development during the first half of 2011, will make this a transformational year for Achillion.”

About Achillion Pharmaceuticals
Achillion is an innovative pharmaceutical company dedicated to bringing important new treatments to patients with infectious disease. Achillion’s proven 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 – hepatitis C, resistant bacterial infections and HIV. For more information on Achillion Pharmaceuticals, please visit www.achillion.com or call 1-203-624-7000 1-203-624-7000.

Forward-Looking Statements

This press release includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks, uncertainties and other factors, including statements with respect to Achillion’s expectations regarding the results of clinical trials and the timing and duration of clinical trials. Among the factors that could cause actual results to differ materially from those indicated by such forward-looking statements are: uncertainties relating to results of clinical trials, unexpected regulatory actions or delays, and Achillion’s ability to obtain additional funding required to conduct its research, development and commercialization activities. These and other risks are described in the reports filed by Achillion with the U.S. Securities and Exchange Commission, including its Annual Report on Form 10-K for the fiscal year ended December 31, 2010.

All forward-looking statements reflect Achillion’s expectations only as of the date of this release and should not be relied upon as reflecting Achillion’s views, expectations or beliefs at any date subsequent to the date of this release. Achillion anticipates that subsequent events and developments may cause these views, expectations and beliefs to change. However, while Achillion may elect to update these forward-looking statements at some point in the future, it specifically disclaims any obligation to do so.