The US Food and Drug Administration (FDA) has approved Gilead Sciences Inc's Harvoni (ledipasvir/sofosbuvir) for expanded use in patients with genotype 4, 5 and 6 chronic hepatitis C virus (HCV) infection and in patients co-infected with HIV. In addition, Harvoni plus ribavirin (RBV) for 12 weeks was approved as an alternate therapy to 24 weeks of Harvoni for treatment-experienced, genotype 1 patients with cirrhosis. Harvoni received regulatory approval for the treatment of chronic HCV genotype 1 infection in adults in the United States in October 2014.

“Harvoni – the first and only single-tablet regimen for the treatment of HCV – continues to demonstrate high cure rates and a tolerable side effect profile across a range of patient populations, including those who have historically been considered among the most difficult to cure,” said Norbert Bischofberger, Ph.D., executive vice president of research and development and chief scientific officer at Gilead.

“We are pleased that the Harvoni label and prescribing information now includes guidance for health care providers on its use in these important HCV patient populations.”

The supplemental new drug application (sNDA) approval for HCV genotypes 4-6 was supported by data from the open-label trials 1119 and ELECTRON-2. Study 1119 evaluated Harvoni for 12 weeks in patients with HCV genotype 4 or 5 who were treatment-naïve and treatment-experienced with or without cirrhosis. Results showed that 93 per cent (41/44) of those with genotype 4 and 93 per cent (38/41) of those with genotype 5 achieved SVR12. ELECTRON-2 evaluated Harvoni for 12 weeks in treatment-naïve or previously-treated patients with genotype 6 HCV infection with or without cirrhosis. In this study, 96 per cent (24/25) of patients achieved SVR12.

The most common adverse events (in at least 10 per cent of subjects) were asthenia (18 per cent), headache (14 per cent) and fatigue (10 per cent).

Patients with HCV/HIV co-infection represent approximately 30 per cent of the total HIV-infected population in the United States. Compared with HCV infection alone, HIV/HCV co-infection is associated with an increased risk of cirrhosis and the subsequent complications of end-stage liver disease and hepatocellular carcinoma (liver cancer).

The sNDA approval for patients with HCV/HIV-1 co-infection was supported by data from the phase 3 open-label ION-4 study, which evaluated Harvoni for 12 weeks for the treatment of genotypes 1 or 4 chronic HCV infection among patients co-infected with HIV. Data demonstrate that 96 per cent (321/335) of patients achieved SVR12. The study included HCV treatment-naïve (45 per cent) and treatment-experienced (55 per cent) patients, including patients with compensated cirrhosis (20 per cent). The majority of patients were taking one of three HIV antiretroviral (ARV) regimens: tenofovir disoproxil fumarate (TDF) and emtricitabine with efavirenz (Atripla), raltegravir or rilpivirine (Complera).

The most common adverse events (in at least 10 per cent of subjects) were headache (20 per cent) and fatigue (17 per cent).

The sNDA approval of Harvoni with RBV for 12 weeks for genotype 1 treatment-experienced HCV patients with cirrhosis was supported by data from the phase 2 SIRIUS study, which evaluated Harvoni plus RBV for 12 weeks or Harvoni without RBV for 24 weeks in genotype 1 HCV-infected patients with compensated cirrhosis who failed prior therapy. Ninety six per cent (74/77) of patients treated with Harvoni plus RBV for 12 weeks, and 97 per cent (75/77) of patients treated with Harvoni for 24 weeks without RBV, achieved SVR12.

The most common adverse reactions (occurring in at least 10 per cent of subjects) among patients receiving Harvoni plus RBV for 12 weeks were asthenia (36 per cent), headache (13 per cent) and cough (11 per cent). In patients receiving Harvoni for 24 weeks, these were asthenia (31 per cent), headache (29 per cent) and fatigue (18 per cent).

The European Medicines Agency also recently approved updates to the Harvoni label to allow for the use of shorter durations of therapy with Harvoni in combination with RBV. Specifically, these include the use of Harvoni plus RBV for 12 weeks in genotypes 1 and 4 HCV-infected patients with compensated cirrhosis, decompensated cirrhosis and post-liver transplant patients. The new label also includes data further supporting use of Harvoni for 12 weeks in patients with genotypes 1 or 4 who are co-infected with HIV and in patients who had previously failed treatment with sofosbuvir plus RBV with or without pegylated interferon.