In
an attempt to overcome this limitation, researchers have studied a ribavirin pro-drug,
taribavirin
(Viramidine), which appears to cause less red blood cell destruction.
In
a study published in the July 2007 Journal of Hepatology, researchers sought
to determine the efficacy and safety of taribavirin versus ribavirin combined
with pegylated interferon in patients with chronic hepatitis C.
In this
Phase 2 open-label study, 180 participants were randomly assigned to receive 180
mcg/week pegylated interferon alfa-2a (Pegasys) plus either taribavirin at doses
of 800, 1200, or 1600 mg or ribavirin at doses of 1000 or 1200 mg once daily.
Results
• The proportions of patients with undetectable
HCV RNA at 12 weeks did not differ significantly between the taribavirin and ribavirin
arms:
• The highest proportions of patients with undetectable
HCV RNA at end of treatment occurred in the taribavirin 1200 mg and ribavirin
groups (63% and 62%, respectively).
• The same held true for sustained virological
response (SVR) rates (37% and 44%, respectively).
• SVR rates were 23%, 37%, and 29% in the 3 taribavirin
dose groups, compared with 44% for ribavirin.
• Significantly fewer patients taking any dose
of taribavirin had severe anemia (hemoglobin <10 g/dL) compared with those
taking ribavirin (4% vs 27%).
Conclusion
In
conclusion, the authors wrote, "Given with interferon, taribavirin produced
SVR rates comparable to those of ribavirin, with a lower occurrence of anemia."
Departments
of Medicine and Transplantation, Division of Hepatology and Complex GI, Physicians
Foundation, California Pacific Medical Center, San Francisco, CA, USA.
08/10/07
Reference RG
Gish, S Arora, KR Reddy, and others. Virological response and safety outcomes
in therapy-naive patients treated for chronic hepatitis C with taribavirin or
ribavirin in combination with pegylated interferon alfa-2a: A randomized, phase
2 study. Journal of Hepatology 47(1): 51-59. July 2007.
