November 11, 2016
The FDA approved Vemlidy at 25 mg for the treatment of chronic hepatitis B virus infection in adults with compensated liver disease, according to a press release from the manufacturer.
Vemlidy (tenofovir alafenamide, Gilead Sciences; TAF) — a nucleoside analog reverse transcriptase inhibitor — is a prodrug of tenofovir that has demonstrated similar efficacy rates at a dose less than one-tenth that of Gilead’s other antiviral for HBV, Viread (tenofovir disoproxil fumarate, Gilead Sciences; TDF), which is given at 300 mg. Clinical data showed TAF improved renal and bone laboratory safety parameters compared with tenofovir disoproxil fumarate.
TAF has a boxed warning in its product label regarding the risks for lactic acidosis/severe hepatomegaly with steatosis and posttreatment severe acute exacerbation of HBV, according to Gilead. It is not recommended for the treatment of HIV-1 infection since safety and efficacy has not been established in patients with HBV/HIV-1 coinfection.
“Chronic hepatitis B is a life-threatening illness that affects up to 2.2 million people in the U.S.,” Calvin Pan, MD, clinical professor of medicine, New York University Langone Medical Center, and investigator in the TAF clinical trials, said in the press release. “Clinical trials demonstrated Vemlidy is efficacious with improved renal and bone safety parameters compared to Viread, representing an important development for people living with this chronic disease.”
The approval is based on data from two international phase 3 clinical studies, where 1,298 treatment-naive and treatment-experienced adult patients with chronic HBV were randomly assigned either TAF or TDF. Both studies met their primary endpoint of noninferiority to TDF based on the percentage of patients with chronic HBV with plasma HBV DNA levels below 29 IU/mL at 48 weeks of therapy, according to Gilead.
TAF and TDF were generally well-tolerated by patients in both studies and discontinuations due to adverse events were 1% and 1.2%. The most common adverse events included headache, abdominal pain, fatigue, cough, nausea and back pain. These events occurred at similar rates in patients receiving either drug.
“Since the mid-1990s, Gilead has been working to improve and simplify care for people living with chronic hepatitis B,” John Milligan, PhD, president and CEO of Gilead Sciences, said in the release. “Vemlidy is the first medication approved to treat this disease in nearly a decade, and we are excited to offer a new, effective option to help advance long-term care for patients.”
Disclosures: Milligan is employed by Gilead Sciences. Pan is an investigator in the TAF clinical trials.