This article is more than 5 years old. Information may no longer be current.

Interferon-free therapy effective in treatment-naive patients with HCV genotype 1

An interferon-free treatment regimen was effective in treatment-naive patients with HCV genotype 1, but less beneficial for nonresponders to prior interferon-based therapy, in a recent preliminary study.

In the multicenter, phase 2a, open-label study, researchers administered 400 mg nonnucleoside NS5B polymerase inhibitor ABT-333 twice daily and a split dose of 1,000-mg or 1,200-mg weight-based ribavirin per day to noncirrhotic patients with HCV genotype 1 for 12 weeks. In addition, patients were assigned either 250 mg (n=19) or 150 mg (n=31) HCV NS3 protease inhibitor ABT-450 plus 100 mg ritonavir (ABT-450/r). All 250-mg recipients were treatment-naive, while 17 of the 150-mg recipients had experienced no or partial response to previous pegylated interferon/ribavirin treatment.

Extended rapid virologic response (RVR) between weeks 4 and 12 occurred in 89% of the 250-mg recipients and 79% of treatment-naive 150-mg recipients. Sustained virologic response (SVR) at 12 weeks after treatment occurred in 95% and 93% of these participants, respectively. At 48 weeks after treatment, all 250-mg recipients and 11 of 13 treatment-naive 150-mg patients who completed therapy had undetectable HCV RNA levels. None underwent virologic breakthrough or relapse during the study.

Among patients with prior treatment experience, 59% had extended RVR and 47% had SVR. Six patients in this group experienced virologic breakthrough during treatment, and three relapsed 2 weeks after therapy.

No patients died or experienced serious adverse events. Common events included fatigue, nausea, headache, dizziness, insomnia and elevated bilirubin levels.

“This preliminary study suggests that the all-oral combination of ABT-450/r, ABT-333 and ribavirin for 12 weeks is associated with [SVR] in a high proportion of previously untreated patients with HCV genotype 1 infection,” the researchers wrote. “ABT-450/r-based regimens that include additional or more-potent agents may have applicability across a broader range of patients with HCV infection, and studies are needed to assess safety and efficacy in patients with a null or partial response to previous therapy, those with cirrhosis and those who also have HIV type 1 infection.”

Disclosure: See the study for a full list of relevant disclosures.