AbbVie Releases Results of Hepatitis C Drug Trial in Japan

A clinical trial conducted by drug maker AbbVie resulted in a 95% cure rate of hepatitis C among Japanese patients who were treated with an all-oral, interferon-free combination drug, the company announced.

The phase 3 trial tested the efficacy and safety of AbbVie’s investigational drug regimen ofombitasvir, paritaprevir and ritonavir, AbbVie said in a release. The drug is an all-oral, two-direct-acting antiviral treatment that is ribavirin free.

Top-line results from the GIFT-I study indicate that the primary endpoint was achieved with a 95% (n=106/112) sustained virologic response rate at 12 weeks after treatment in a subgroup of patients who had not previously been treated for genotype 1b chronic hepatitis C infection, according to AbbVie.Study participants were adult Japanese patients without cirrhosis who were eligible for therapy with interferon and had a high viral load, the release states.

"AbbVie is committed to advancing HCV care with the goal of evaluating our treatment in a broad range of patients around the world," said Scott Brun, M.D., AbbVie’s vice president of pharmaceutical development. "The GIFT-I results are encouraging and support moving forward with our Japan development program, with a local regulatory submission anticipated in the first quarter of 2015.”

AbbVie said it would publish detailed results from the GIFT-I study at a later date.

A version of this AbbVie drug regimen has already been approved in the United States under the brand Viekira Pak. Regulatory approvals have also been granted in Canada and, more recently, by the European Commission under the brand name Viekirax + Exviera.

Roughly 2 million people in Japan are infected with hepatitis C, according to the release. The World Health Organization estimates that globally there could be as many as 15 million people infected with the virus.

Some people simultaneously clear the virus with the help of their own immune system. For those who develop a chronic hepatitis C virus infection, the risk of cirrhosis of the liver is 15% to 30% within a 20-year span, according to WHO.

The Japanese study involved 363 adult patients who were given a 12 week-regimen of ombitasvir/paritaprevir/ritonavir. It included patients without cirrhosis and some with compensated cirrhosis who had either never been treated or had failed previous treatment with interferon with or without ribavirin, according to the release.

Nasopharyngitis, headache, and edema peripheral were the most common adverse events among the patients without cirrhosis. Among that group two patients discontinued the study because the events.

Within the primary efficacy patient population, there were no on-treatment virologic failures and 2.8% of patients (n=3/109) experienced relapse, the release states.

The direct-acting antiviral treatment targets and inhibits viral-replicating proteins. The treatment being tested in Japan for people with genotype 1b of the virus is a once daily fixed-dosed combination of 150 mg of paritaprevir and 100 mg ritonavir with 25 mg of ombitasvir.