Safety and Efficacy of ANA598 Administered With Pegylated Interferon and Ribavirin in Genotype-1 Patients With Chronic HCV Infection

Eligible patients with chronic hepatitis C infection (HCV genotype 1) will be randomized to
treatment with 200 mg BID (total daily dose 400 mg) ANA598 or matching placebo, while
receiving co-administered pegylated interferon and ribavirin (standard-of-care, SOC). All
patients receiving ANA598 will receive a loading dose of 800 mg BID (total dose 1600 mg) on
Day 1.

Treatment-Naïve Patients:

Enrollment will include approximately 133 treatment-naïve Genotype 1 patients with chronic
HCV infection (100 randomized to receive ANA598 + SOC, and 33 randomized to receive matching
placebo + SOC).

Treatment-naïve patients will be treated for either 28 weeks or 48 weeks, depending on
response to treatment. Patients with undetectable HCV RNA at Week 8 and at subsequent
visits will complete all treatment at Week 28.

Patients with Prior SOC Treatment (All will receive 48 Weeks of therapy):

Approximately 113 patients categorized as having prior relapse , prior partial response or
prior viral breakthrough to previous treatment will be randomized to treatment with ANA598
200 mg BID + SOC or placebo + SOC (80 randomized to be treated with ANA598 + SOC, and 33
randomized to be treated with placebo + SOC).

Approximately 28 treatment-experienced patients categorized as null responders to previous
treatment will be assigned treatment for 48 weeks with ANA598 200mg BID and co-administered
pegylated interferon and ribavirin.