The Japanese Ministry of Health, Labor and Welfare has approved the combination of daclatasvir (Daklinza, Bristol-Myers Squibb) and asunaprevir (Sunvepra, Bristol-Myers Squibb) for treatment of patients with genotype 1 chronic hepatitis C virus infection (HCV), including those with compensated cirrhosis, the company announced today.

Daclatasvir is a potent, pan-genotypic NS5A replication complex inhibitor, and asunaprevir is a NS3/4A protease inhibitor.

The combination is the first all-oral interferon-free and ribavirin-free hepatitis C treatment approved in Japan.

About 70% of the 1.2 million people living with HCV in Japan have genotype 1b, Bristol-Myers Squibb says in a news release.

"Japan has a unique hepatitis C patient population, many of whom are older and have been unable to take, or respond to, traditional therapies, so we have a real sense of urgency to treat these patients now," said Kazuaki Chayama, MD, PhD, from Hiroshima University, Japan.

The approval of the daclatasvir plus asunaprevir regimen "offers for the first time a treatment option that addresses many of the unmet needs for our HCV patients," Dr. Chayama said.

In Japan, the daclatasvir plus asunaprevir combination is indicated for the improvement of viremia in patients with chronic HCV genotype 1 with or without compensated cirrhosis who are ineligible or intolerant to interferon-based therapy, as well as patients who have failed to respond to interferon-based therapy.

In a phase 3 study led by Dr. Chayama, 84.7% of Japanese HCV patients with genotype 1b treated with the daclatasvir/asunaprevir combination achieved sustained virologic response 24 weeks after the end of treatment (SVR24).

Among patients 65 years of age or older who were either interferon-ineligible or intolerant, 91.9% achieved SVR24. Patients with compensated cirrhosis present at baseline had overall SVR24 rates of 90.9%, the company notes.

Only 5% of study subjects discontinued therapy because of adverse events. The rate of serious adverse events was low (5.9%), and few serious adverse events were experienced by more than 1 patient, the company says. Nasopharyngitis was the most common adverse effect (30.2%).

In February 2014, the US Food and Drug Administration gave the daclatasvir plus asunaprevir regimen breakthrough therapy designation for use as a combination therapy in the treatment of genotype 1b HCV infection.

Daclatasvir is also being studied in combination with sofosbuvir (Sovaldi, Gilead Sciences) in different patient populations including pre- and posttransplant patients, HIV/HCV coinfected patients, and patients with genotype 3.