New data from 4 phase III trials for the treatment of viral hepatitis C (HCV) with sofosbuvir (SOF) and ribavirin (RBV) have shown that a 12-week regimen is effective in the treatment of 1 to 6 genotypes of HCV. The 24-week persistent virological response (CBO) was found to be essentially identical to the 12-week CBO, maintaining the confidence that this combination of drugs leads to recovery. Patients with the 3rd genotype of the virus are better assisted by a 16-week treatment.

The new data are the results of observations exceeding 24 weeks after stopping treatment. 24 weeks is the traditional milestone for treating HCV, but in recent years the U.S. Food and Drug Administration (FDA) and pharmaceutical companies have lobbied for a further 12 weeks. However, since the new drug significantly affects the end result of HCV therapy, an earlier endpoint should be considered. The results of this study were presented at the annual scientific conference of the American College of Gastroenterology (ACG).

According to the researchers, the results are an important next step in the treatment of HCV and the researchers very quickly achieved pronounced positive treatment results. A study is also underway on possible late relapses and questions on the development of resistance in the virus are being treated.

The results of this work were obtained from 4 phase III studies:

In all studies, the primary endpoint evaluated was a persistent virologic response (HCV RNA less than 25 IU / ml) 12 weeks after treatment (CBO12).

In these studies, the average age of participants was 53 years (19 to 77 years) and the average body mass index was 28 kg / m²; (17-56 kg / m²;). The patient demographics coincided with the average population of HCV patients in the United States.

Compensated cirrhosis was detected during the initial visit in 17% of patients in the NEUTRINO study, 21% in the FISSION study, 18% in the POSITRON study and 33% in the FUSION study.

In all studies, CBO12 was higher in patients without cirrhosis. Patients with the 2nd genotype of the virus showed a higher frequency of CBO12 compared to patients with the 3rd genotype.

The frequency of the persistent virological response 24 weeks after the end of treatment was comparable to that obtained 12 weeks after the end of treatment.

These results suggest that doctors will soon receive new treatment options for HCV with sofosbuvir and other new drugs.

On October 25, 2013, the FDA Advisory Committee unanimously recommended approval of sofosbuvir based on 12-week results. A final FDA decision on this matter is expected by December 8, 2013.