Yesterday drugmaker ViroPharma (NASDAQ:VPHM) announced that it had completed enrolling the initial treatment groups in a phase 2 study of its hepatitis C treatment HCV-796.

Finishing enrollment means that the clock can start ticking on when these patients will complete treatment. ViroPharma and partner Wyeth (NYSE:WYE) expect to release interim data after four weeks of drug treatment in the third quarter of this year; the twelve-week data is expected to come out in the fourth quarter.

Keep in mind that the data that ViroPharma will announce later in the year is only preliminary. The study is slated to run a total of 72 weeks. More arms of the study, using different dosages of the drug, will open up after the interim results are released.

The nice thing about hepatitis C therapies is that early results of a drug's efficacy are generally highly predictive of the long-term outcomes for patients on these compounds. Therefore investors should have a much better idea of the potential for HCV-796 by the time 2008 rolls around.

In late 2006, HCV-796 produced very positive phase 1b study results when compared against the current standard of care for hepatitis C. After fourteen days of treatment, when HCV-796 was added to pegylated interferon, patients had significantly lower amounts of hepatitis C in their bodies compared to those who didn't get HCV-796.

With multiple new treatment options for hepatitis C from different biopharmas in mid- and late-stage clinical studies, the treatment landscape for this disease is going to change dramatically over the next several years. If the HCV-796 phase 2 study results are as strong as the phase 1 results were, the drug stands a good chance of being one of these novel treatment options.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool has a disclosure policy.