Inhibitex has initiated a Phase 1b clinical trial of INX-189, its nucleotide polymerase inhibitor, for the treatment of chronic infections caused by the hepatitis C virus (HCV).

The trial, which is being conducted in the US, will consist of a double-blind, dose escalation and placebo-controlled study.

The trial is designed to assess the safety, tolerability and pharmacokinetics of INX-189 administered orally once-daily for seven days in patients with HCV genotype 1 who have not received previous treatment.

Each cohort will enroll ten patients, in which eight will receive INX-189 and two will receive placebo, and the first cohort will receive 9mg of INX-189, once daily.

In addition to evaluating INX-189 as a monotherapy, the company plans to evaluate two dose levels of INX-189 in combination with ribavirin – the currently approved drug for HCV treatment.

The INX-189 dose levels to be evaluated in combination with ribavirin will be determined depending on the results of the monotherapy cohorts.