CROI 2014A combination of low-dose daclatasvir and Olysio (simeprevir) cured a relatively high proportion of people with genotype 1b of hepatitis C virus (HCV), but just two thirds of a small group of genotype 1a's. Findings from the LEAGUE-1 trial were presented at the Conference on Retroviruses and Opportunistic Infections (CROI) in Boston and reported by aidsmap.

The safety and efficacy study included 147 participants with genotype 1b, including 104 treatment-naive participants and 43 prior null responders. Another part of the study included 21 people with genotype 1a.

Those with genotype 1b randomly received 30 milligrams a day of Bristol-Myers Squibb's NS5A inhibitor daclatasvir and 150 mg a day of Janssen's Olysio, with or without ribavirin. Twelve weeks into treatment they were randomized again, this time either to stop therapy or to continue for an additional 12 weeks.

All of the participants with genotype 1a took daclatasvir, Olysio and ribavirin for 24 weeks.

Eighty-one percent of the treatment-naive 1b's who received 12 weeks of two-drug treatment and 89 percent who received 24 weeks achieved a sustained virologic response 12 weeks after completing therapy (SVR12, considered a cure). The cure rates for those who received three drugs were 75 percent in the 12-week group and 74 percent in the 24-week group.

Among the null responder participants with genotype 1b, 65 percent of those who took the two-drug regimen and 95 percent who took the three-drug cocktail achieved an SVR12.

Sixty-seven percent of the participants with genotype 1a were cured. The four people, comprising the remaining 33 percent, who were not cured experienced viral breakthrough.

Daclatasvir and Olysio proved generally safe and well tolerated, with 9 percent of those taking the two-drug regimen and 4 percent who also took ribavirin experiencing serious side effects. A respective 3 and 2 percent stopped treatment as a result of side effects.

To read the aidsmap story, click here.

To watch a webcast of the CROI presentation, click here.