More CCO stuff
48 vs 72 Weeks of Peginterferon alfa-2b/Ribavirin in Slow Responders Infected with Genotype 1 HCV
Stefan Zeuzem, MD:
Several studies evaluated strategies for optimizing or individualizing the duration of HCV therapy. In Europe, but not in the United States, peginterferons are approved for 24 weeks of treatment in patients who are infected with genotype 1 HCV with a low baseline HCV RNA level and rapid virologic response.[21,22] Several studies have shown shorter treatment durations are effective in subsets of genotype 1 patients.[23,24] However, the recommendation for patients with genotype 1 HCV who are standard responders (defined as patients achieving undetectable HCV RNA at Week 12) is 48 weeks of therapy, and there have been various studies—a large German multicenter study,[25] a large Spanish multicenter study,[26] and a large US study[27]—showing that it can be beneficial to continue treatment for 72 weeks in slow responders (defined as patients achieving a > 2 log decline in HCV RNA at Week 12 of therapy, but detectable HCV RNA).
At 2009 EASL, Buti and colleagues[28] presented data from the SUCCESS study, a trial investigating 48 vs 72 weeks of therapy in treatment-naive genotype 1 HCV–infected slow responders to peginterferon alfa-2b/ribavirin but with a different design compared with the previous trials (Capsule Summary). The current study enrolled 1428 treatment-naive patients, but only the 159 slow responders were randomized at Week 24 to receive 48 or 72 weeks of therapy. Patients with complete early virologic response (n = 816) received 48 weeks of treatment. Slow response was defined as detectable HCV RNA at Week 12, but with a ≥ 2 log10 IU/mL decrease from baseline, followed by undetectable HCV RNA at Week 24. By contrast, the previous German multicenter study randomized all patients to either 48 or 72 weeks of treatment, and the post hoc analysis showed that slow responders benefited from extended therapy.[25]
In the SUCCESS study, the intent-to-treat analysis showed that the SVR rate was slightly higher at 48% vs 43% with 72 vs 48 weeks of treatment, respectively, but the difference was not statistically significant (P = .6445). Of note, relapse rates were also not statistically significantly different between the 2 arms (33% vs 47% with 72 vs 48 weeks of therapy, respectively; P = .1699).