Reuters Health Information (2007-05-15): New HCV protease inhibitor effective against hepatitis C
Drug & Device Development
New HCV protease inhibitor effective against hepatitis C
Last Updated: 2007-05-15 13:22:16 -0400 (Reuters Health)
NEW YORK (Reuters Health) - A new, oral HCV protease inhibitor, SCH 503034, is well tolerated and may be effective against hepatitis C (HCV) genotype 1 that is refractory to interferon treatment, according to a report in the April issue of Gastroenterology.
SCH 503034 is a specific inhibitor of NS3 protease, which plays an essential role in the replication of HCV, the authors explain.
Dr. Christoph Sarrazin from Saarland University Hospital, Hamburg, Germany and associates evaluated the safety and tolerability of SCH 503034, alone and in combination with pegylated interferon-alpha-2b (IFN), in 26 patients with chronic HCV infection that had not responded to treatment with IFN with or without ribavirin.
Both as monotherapy and in combination with IFN, SCH 503034 was generally well tolerated, the authors report.
One week of treatment with SCH 503034 alone resulted in a mean maximal reduction in HCV RNA of 1.08 log10 at 200 mg 3 times daily, and 1.61 log10 at 400 mg 3 times daily, the investigators say.
Combination therapy with SCH 503034 and IFN resulted in greater decreases in HCV RNA than with IFN alone, the researchers note. The best results (a mean decrease in HCV RNA of 2.68 log10 after 2 weeks) were seen with the combination of SCH 503034 400 mg 3 times daily and IFN.
"Evaluation of virologic response during monotherapy and combination therapy suggests that combination SCH 503034 plus IFN was associated with anti-HCV activity in these patients who had previously not responded to IFN with or without ribavirin," the authors report.
"Phase II clinical trials with HCV genotype 1 nonresponders are underway to determine the optimum dosing and exposure levels for this potentially important therapeutic regimen," the researchers add.
"Novel oral antiviral approaches are exciting and fashionable," writes Dr. Jean-Michel Pawlotsky from Hopital Henri Mondor, Creteil, France in a related editorial. "The spectacular antiviral efficacy of some of these drugs should not, however, be allowed to mask the specific new problems they raise."
"Although adjunction of an oral HCV inhibitor may give interesting results, other options are already available for the treatment of chronic hepatitis C, including optimization of the current pegylated IFN-alpha-ribavirin combination," the editorial concludes. "All these options should be explored, as they may benefit patients in the near future."