Sovaldi, a once-daily nucleotide analog polymerase inhibitor, is indicated for use in combination with ribavirin (RBV) for 12 weeks and the combination is the first all-oral, interferon-free treatment regimen for genotype 2 HCV infection.
The approval is based on data from a Phase III trial conducted in Japan (Study GS-US-334-0118) among treatment-naïve and treatment-experienced genotype 2 patients.
In the trial, 96% of genotype 2 HCV-infected patients received 12 weeks of an all-oral regimen of Sovaldi plus RBV 600-1,000mg/day achieving a sustained virologic response 12 weeks after completing therapy (SVR12).
Gilead Research and Development executive vice-president and chief scientific officer Norbert Bischofberger said: "There is a need in Japan for new HCV treatment options that are more effective and better tolerated and we have been pleased to partner with the medical community here in Japan to demonstrate the efficacy and safety of Sovaldi.
"We look forward to making Sovaldi available in Japan as quickly as possible, while simultaneously continuing to work with the agency on its review of our second application for an all-oral sofosbuvir-based regimen for the treatment of genotype 1 HCV infection."
The Japanese approval is also supported by SVR12 results from four international Phase III trials FISSION, FUSION, POSITRON and VALENCE, which included genotype 2 HCV patients.
The company said that patients who achieve SVR12 are considered cured of HCV infection.
In September 2014, the company filed a new drug application (NDA) in Japan for a single-tablet regimen of sofosbuvir and the NS5A inhibitor ledipasvir to treat genotype 1 HCV infected patients.