"12 weeks' stopping rule" in the treatment of genotype 1 chronic hepatitis C: two prognostic categories under the same label?

Objective: The current guidelines recommend maintenance of combined therapy for hepatitis C virus (HCV) genotype-1 chronic hepatitis when HCV-RNA is undetectable or < or = 2 log10 of baseline after 12 weeks of therapy. The aim of this study was to investigate whether the probability of obtaining sustained viral (SVR) response is similar when HCV-RNA is undetectable or is present at < or = 2 log10 level after 12 weeks of therapy.

Material And Methods: Retrospective analysis was carried out in 208 HCV genotype-1 chronic hepatitis patients treated with pegylated interferon and ribavirin with available data on HCV viral load after 12 weeks of therapy and definite data on the results of therapy.

Results: Seventy-six (68.5%) out of 111 patients with undetectable HCV-RNA and 4 (11.8%) out of 34 patients with HCV-RNA < or = 2 log10 from baseline at week 12 reached SVR (odds ratio 16.29, 95% CI 5.08-67.12; p < 0.001). Sixty-three patients did not meet any of these criteria and therapy was discontinued.

Conclusions: The "12-week stopping rule" includes two different categories of responders considered candidates for maintained therapy, but the probability of obtaining SVR is very low in patients with HCV-RNA that is still detectable at this time of treatment. We suggest that, in these partial responders, the prolongation of therapy should be decided on an individual basis.