Gilead Sciences announced that the US Food and Drug Administration (FDA) has approved supplemental indications for Harvoni (ledipasvir 90 mg/sofosbuvir 400 mg) tablets and Sovaldi (sofosbuvir 400 mg) tablets for the treatment of chronic hepatitis C virus (HCV) infection in adolescents without cirrhosis or with compensated cirrhosis, 12 years of age and older, or weighing at least 35kg. Harvoni was approved for paediatric patients with genotype 1, 4, 5 or 6 chronic HCV infection. Sovaldi was approved for paediatric patients with genotype 2 or 3 chronic HCV infection, in combination with ribavirin. There are an estimated 23,000-46,000 pediatric HCV patients in the United States, most of whom were infected with the virus at birth.

"The approvals of Sovaldi and Harvoni for pediatric patients will enable adolescents to finally benefit from interferon-free treatment for HCV infection," said Karen Murray, M.D., professor of paediatrics at the University of Washington School of Medicine and Seattle Children's. "These therapies address a significant unmet medical need and represent an important advance for HCV-infected adolescents."

"Gilead's goal is to develop and deliver treatments that provide all patients with HCV the potential to be cured," said Norbert Bischofberger, Ph.D., executive vice president of research and development and chief scientific officer at Gilead. "For the first time, children 12 and older in the United States with genotypes 1 through 6 chronic HCV infection now have options of two direct-acting antiviral regimens that offer high cure rates while eliminating the need for interferon injections."

Harvoni and Sovaldi each have a boxed warning in their respective product labels regarding the risk of hepatitis B virus reactivation in HCV/HBV co-infected patients. See below for important safety information.

The supplemental new drug application (sNDA) approval is supported by data from an open-label clinical trial (Study 1116), which evaluated 12 weeks of treatment with Harvoni once-daily in genotype 1 treatment-naïve and treatment-experienced HCV-infected adolescents 12 years of age and older without cirrhosis or with compensated cirrhosis. The SVR12 rate was 98 percent overall (98/100). No subject experienced on-treatment virologic failure or relapse. Two subjects were lost to follow-up.

Adverse events were consistent with those observed in clinical studies of Harvoni in adults. The most common adverse reactions (=10 percent, all grades) observed with treatment with Harvoni in HCV-infected paediatric patients were fatigue, headache and asthenia.

The sNDA approval is supported by data from an open-label clinical trial (Study 1112), which evaluated 12 or 24 weeks of treatment with Sovaldi and weight-based ribavirin in adolescents 12 years of age and older with HCV genotype 2 or 3. The SVR12 rate was 100% (13/13) in genotype 2 patients and 97% (36/37) in genotype 3 patients. No subject experienced on-treatment virologic failure or relapse. One patient was lost to follow up.

Adverse events were consistent with those observed in clinical studies of Sovaldi in adults. The most common adverse reactions (=15 percent, all grades) observed with treatment with Sovaldi and ribavirin for 12 or 24 weeks in HCV-infected paediatric patients were fatigue, headache and nausea.