100 percent SVR4 in 8 weeks

NEW HAVEN, Conn.—Achillion Pharmaceuticals, Inc. today announced interim results from an ongoing Phase 2 proxy study evaluating ACH-3102, Achillion's second-generation NS5A inhibitor, in combination with sofosbuvir, without ribavirin, for eight weeks of treatment in patients with treatment-naive genotype 1 chronic hepatitis C virus (HCV) infection. Of the 12 patients treated, 100 percent (n=12/12) remained HCV RNA undetectable four weeks after completing therapy (SVR4). Based upon these results, 12 additional patients will begin treatment with six weeks of once daily ACH-3102 and sofosbuvir.

"ACH-3102 continues to demonstrate good safety and tolerability through three Phase 2 studies. We believe these studies also confirm a differentiated efficacy profile for an NS5A inhibitor. Achieving 100 percent SVR4 with eight weeks of treatment with sofosbuvir serving as a nucleotide proxy indicate that dosing 50 mg once daily of ACH-3102 plus a nucleotide inhibitor has the potential to achieve commercially competitive results for curing HCV in a short duration, ribavirin-free doublet," stated David Apelian, M.D., Ph.D., executive vice president and chief medical officer at Achillion. "In addition, understanding how ACH-3102 performs with sofosbuvir provides valuable insight for the design of our proprietary combination trial with ACH-3102 and ACH-3422, a uridine-analog nucleotide that continues to advance through its Phase 1 clinical development program."

Milind Deshpande, Ph.D., president and CEO of Achillion commented, "As we continue to achieve clinical milestones, we remain focused on execution of the broader clinical development strategy for our HCV portfolio. We expect that Phase 1 proof-of-concept results with ACH-3422 will be reported during the fall of this year, which we anticipate will lead to the start of a Phase 2 combination program to evaluate our proprietary doublet regimen for an eight week, or potentially shorter, treatment regimen for HCV that will begin before the end of 2014."

Achillion is conducting a Phase 2, open-label, randomized, partial-crossover study to evaluate the efficacy, safety, and tolerability of eight weeks or six weeks of ACH-3102 and sofosbuvir, a marketed nucleotide polymerase inhibitor, without ribavirin, in treatment-naive genotype 1 HCV-infected patients. The primary objective of the study is determination of sustained viral response 12 weeks (SVR12) after the completion of therapy. Eighteen patients were enrolled, including six observational patients. Twelve patients completed eight weeks of treatment consisting of 50 mg of ACH-3102 and 400 mg of sofosbuvir administered once daily while observational patients received no drug during this phase of the trial. Ten of the 12 patients receiving eight weeks of treatment had genotype 1a HCV with median HCV RNA at baseline of 7.22 log10 (range 5.5 - 7.8 log10). No on-treatment viral breakthrough or post-treatment viral relapse has been observed to date. ACH-3102 and sofosbuvir were well tolerated with no significant adverse events, ECG findings, or lab abnormalities observed during treatment.

Following achievement of the pre-specified response rate of 100 percent, the six observational patients plus six additional patients will be enrolled and receive six weeks of treatment consisting of 50 mg of ACH-3102 and 400 mg of sofosbuvir administered once daily. Achillion anticipates that SVR4 results from the crossover cohort will be reported by the end of 2014.

The hepatitis C virus is the most common cause of viral hepatitis. It is currently estimated that more than 150 million people are infected with HCV worldwide including more than 5 million people in the United States. Three-fourths of the HCV patient population is undiagnosed; it is a silent epidemic and a major global health threat. Chronic hepatitis, if left untreated, can lead to permanent liver damage that can result in the development of liver cancer, liver failure or death.

Achillion is an innovative pharmaceutical company dedicated to bringing important new treatments to patients with infectious disease. Achillion's discovery, clinical development, and commercial teams have advanced multiple novel product candidates with proven mechanisms of action into studies and toward the market. Achillion is focused on solutions for the most challenging problems in infectious disease including HCV and resistant bacterial infections.

Source: Achillion Pharmaceuticals