Because of this high response
rate, some experts have hypothesized that shorter treatment duration than the
standard 24 weeks may be adequate for some genotype 2/3 patients.
An international
team of researchers conducted a large, randomized non-inferiority trial to determine
whether 16 weeks of treatment would work as well as 24 weeks in this population.
Results were reported in the July 12, 2007 New England Journal of Medicine.
Rapid virological response (RVR) was
defined as undetectable HCV RNA by week 4 of therapy. SVR was defined as undetectable
serum HCV RNA (< 50 IU/mL) 24 weeks after the end of treatment. Relapse was
defined as detectable HCV RNA during follow-up in patients who had undetectable
HCV RNA at the end of treatment.
Results
• The study failed to demonstrate
that the 16-week regimen was non-inferior to the 24-week regimen.
•
The overall SVR rate was significantly lower in
patients treated for 16 weeks compared with those treated for 24 weeks (62% vs
70%; P < 0.001).
•
The relapse rate was significantly higher in the
16-week group compared with the 24-week group (31% vs 18%; P<0.001).
•
Looking only at the subset of patients with pre-treatment
serum HCV RNA levels of 400,000 IU/mL or less, however, the SVR rates were similar
in the 16-week and 24-week arms (82% vs 81%).
•
Among patients who achieved rapid virological response,
SVR rates were 79% in the 16-week group and 85% in the 24-week group (P = 0.02).
Conclusion
In
conclusion, the authors wrote, "Treatment with peginterferon and ribavirin
for 16 weeks in patients infected with HCV genotype 2 or 3 results in a lower
overall sustained virologic response rate than treatment with the standard 24-week
regimen." However, the results suggest that a 16-week course of therapy
may be adequate for a carefully selected subgroup of patients.
Virginia
Commonwealth University Medical Center, Richmond, VA; Ospedali Riuniti, Bergamo,
Italy; Saint Louis University, St. Louis, MO; University of Florida, Gainesville,
FL; Royal Adelaide Hospital, Adelaide, Australia; Universitat Autònoma
de Barcelona, Barcelona, Spain; University of Alberta Hospital, Edmonton, Canada;
Hôpital Purpan, Toulouse, France; Saarland University Hospital, Homburg/Saar,
Germany; Roche, Nutley, NJ; Roche, Welwyn, UK.
7/20/07
Reference ML
Shiffman, F Suter, BR Bacon, and others. Peginterferon Alfa-2a and Ribavirin for
16 or 24 Weeks in HCV Genotype 2 or 3. New England Journal of Medicine
357(2): 124-134. July 12, 2007.
