The FDA has approved a second drug to help prevent human immunodeficiency virus (HIV) infection among adults and teens at risk for the illness.
Emtricitabine/tenofovir alafenamide, 200 mg/25 mg (Descovy, Gilead Sciences), adds a new option for pre-exposure prophylaxis (PrEP) among patients weighing at least 35 kg (about 77 pounds). Although the drug can reduce the risk of HIV-1 infection from sex, it isn’t indicated for people who have receptive vaginal sex because its effectiveness hasn’t been tested in this population.
Under PrEP, people who do not have HIV take daily medicine to reduce their risk of getting HIV if they are exposed to the virus. PrEP should be part of a comprehensive strategy, including adherence to daily administration and safer sex practices, including condoms, to reduce the risk of sexually acquired infections.
The safety and efficacy of emtricitabine/tenofovir alafenamide for PrEP were evaluated in a randomized, double-blind, multinational trial in 5,387 HIV-negative men and transgender women who have sex with men and were at risk of HIV-1 infection. The trial compared once-daily emtricitabine/tenofovir alafenamide to emtricitabine/tenofovir disoproxil fumarate, 200 mg/300 mg (Truvada, Gilead Sciences), which won FDA approval in 2012 to prevent sexual transmission of HIV; participants were followed for 48 to 96 weeks. The two medications had similar results in reducing the risk of acquiring HIV-1 infection. The most common adverse reaction in people without HIV who were taking emtricitabine/tenofovir alafenamide for PrEP was diarrhea.
A boxed warning notes that people with the hepatitis B virus (HBV) who take emtricitabine/tenofovir alafenamide should be alert to the risk of HBV exacerbations if they discontinue products with emtricitabine or tenofovir disproxil fumarate. The drug should only be prescribed to people confirmed to be HIV-negative immediately prior to initiating it and at least every three months during use.
The FDA approved Descovy in 2016 in combination with other antiretoviral drugs to treat HIV-1 infection in adult and pediatric patients.
Source: FDA, October 3, 2019