US regulators have expanded the approved indications for AbbVie’s hepatitis C therapy Viekira Pak, offering a potential cure to a difficult-to-treat sub-population of patients.

The US Food and Drug Administration has cleared use of Viekira Pak (ombitasvir, paritaprevir, and ritonavir tablets; dasabuvir tablets) without ribavirin (RBV) in patients with genotype 1b (GT1b) chronic hepatitis C (HCV) infection who also have compensated cirrhosis (Child-Pugh A). 

The therapy was approved in the US in December last year for use - with or without RBV - to treat adults with GT1 chronic forms of the disease, after clinical trials showed 95%-100% cure rates and a good tolerability profile.

Its expanded approval comes after data from the TURQUOISE-III study demonstrated 100 percent sustained virologic response at 12 weeks post-treatment (SVR12) in patients with GT1b and compensated cirrhosis, with none discontinuing treatment due to adverse events. 

"This approval is especially significant because patients with chronic HCV with compensated cirrhosis are among the tough to treat, and in our study VIEKIRA PAK demonstrated 100 percent cure rates in GT1b patients without the use of ribavirin,’ noted Michael Severino, AbbVie’s chief scientific officer.

“The ability to cure these individuals with just 12 weeks of treatment and without the need for ribavirin is a great benefit," said TURQUOISE-III lead investigator Jordan Feld, research director and clinician scientist at the Toronto Center for Liver Disease, Canada. "The outstanding 100 percent cure rate from the study confirms that this is likely to be a very effective strategy."

The Centers for Disease Control and Prevention estimates that around 2.7 million people are chronically infected with HCV in the US, with GT1 the most common form, of which 77 percent are GT1a and 23 percent GT1b.