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ACH-1625 HCV Protease Inhibitor Starts Phase 2 Trial

Achillion Pharmaceuticals recently announced that the first patients have started treatment in a Phase 2 clinical trial of the experimental HCV protease inhibitor ACH-1625 plus pegylated interferon and ribavirin.

Below is an edited excerpt from an Achillion press release describing the study.

Achillion Initiates 12-Week Dosing in Phase 2 Trial of ACH-1625 for the Treatment of Chronic Hepatitis C

New Haven, Conn. -- June 22, 2011 -- Achillion Pharmaceuticals, Inc. (Nasdaq:ACHN) today announced that the Company has initiated patient dosing in segment 2 of its Phase 2 clinical trial of ACH-1625 for the treatment of hepatitis C virus (HCV) for genotype 1 treatment-naive HCV-infected patients. ACH-1625, discovered and advanced by Achillion, is a potent small molecule inhibitor of HCV protease, an enzyme necessary for viral replication.

The clinical trial has advanced into the second segment of a Phase 2a, randomized, double-blind trial evaluating the safety, tolerability and antiviral activity of oral ACH-1625 in combination with standard of care (SOC) consisting of pegylated interferon alfa-2a and ribavirin. Patients will be randomized to receive once daily doses of 200 mg, 400 mg or 800 mg of ACH-1625 in combination with SOC for 12 weeks of dosing. Patients will continue to receive an additional 12 weeks of pegylated interferon alfa-2a and ribavirin and eligible to discontinue treatment at week 24 if they achieve extended rapid virologic response (eRVR) at week 12. Patients who do not achieve an eRVR will continue to receive SOC until week 48.

The trial will take place in the United States and Europe and is designed to enroll approximately 60 HCV-infected patients. The 12-week complete early virologic response (cEVR) trial results are anticipated to be announced in the fourth quarter of 2011.

"Initiating the second segment of this Phase 2 clinical trial allows us to build upon the robust RVR results we observed with ACH-1625, and to further augment the safety and efficacy database by taking the opportunity to study multiple doses of ACH-1625," commented Elizabeth A. Olek, DO, Vice President and Chief Medical Officer of Achillion. "We expect that the results will provide important insight to benchmark the activity of our once-daily protease inhibitor and we look forward to reporting cEVR results by the end of this year."

"This next study segment with ACH-1625 is yet another important milestone achieved for this potentially best-in-class protease inhibitor and for Achillion's broader HCV pipeline," said Michael D. Kishbauch, President and Chief Executive Officer of Achillion. "It should be recalled that, very recently, we announced the start of Phase 1 on Achillion's high-potency, pan-genotypic protease inhibitor, ACH-2684, and with the upcoming start of Phase 1 on our first NS5A inhibitor, ACH-2928, Achillion remains poised to deliver on a number of clinical milestones over the next few quarters that we believe will significantly enhance our overall position within the important and promising HCV market."

About ACH-1625

ACH-1625 is a HCV protease inhibitor designed and synthesized based on crystal structures of enzyme/inhibitor complex. ACH-1625 is an open chain, non-covalent, reversible inhibitor of NS3 protease. In preclinical studies, ACH-1625 demonstrated high potency, unique pharmacokinetic properties and an excellent safety profile at high drug exposures. ACH-1625 has rapid and extensive partitioning to the liver, as well as high liver/plasma ratios. ACH-1625 has shown low single-digit nanomolar potency that is specific to HCV. It is equipotent against HCV genotypes 1a and 1b at IC50 of approximately 1nM.

In the first segment of a Phase 2a clinical study, HCV-infected patients receiving doses of 200 mg, 400 mg, or 800 mg of ACH-1625 in combination with SOC achieved a rapid viral response of 75 -- 81% compared to an RVR of 20% for patients receiving SOC only. ACH-1625 was well tolerated at all doses with no serious adverse events reported and adverse events which were reported as mild to moderate and transient.

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 including hepatitis C and resistant bacterial infections. For more information on Achillion Pharmaceuticals, please visit www.achillion.com or call 1-203-624-7000.

7/8/11

Source
Achillion Pharmaceuticals. Achillion Initiates 12-Week Dosing in Phase 2 Trial of ACH-1625 for the Treatment of Chronic Hepatitis C. Press release. June 22, 2011.