The Food and Drug Administration (FDA) has approved Descovy for HIV preexposure prophylaxis (PrEP). PrEP is taken by HIV-negative individuals to reduce their risk of contracting the retrovirus if exposed. Descovy is the second drug to be approved for this indication; Truvada, a daily fixed-dose combination of emtricitabine 200 mg and tenofovir disoproxil fumarate 300 mg, approved in 2012, was the first. Descovy is a combination of emtricitabine (200 mg) and tenofovir alafenamide (25 mg), both HIV nucleoside analog reverse transcriptase inhibitors. Originally approved in 2016 for the treatment of HIV in combination with other antiretroviral drugs, Descovy is now approved for use as PrEP in at-risk adults and adolescents who weigh 35 kg or more. It is not approved for women who have vaginal sex with an infected partner (referred to as receptive vaginal sex) because there is a lack of study data in this population.

The efficacy of Descovy was determined in a randomized, double-blind, multinational clinical trial of 5,387 HIV-negative men and transgender women who have sex with men with HIV-1 infection. Descovy was compared with Truvada, and both drugs were found to be similarly effective.

The most common adverse effect of Descovy is diarrhea. The drug also carries a boxed warning that patients who have hepatitis B virus (HBV) can experience exacerbations of HBV upon discontinuing Descovy. Immune reconstitution syndrome, new onset or worsening of renal impairment, and lactic acidosis and severe hepatomegaly with steatosis are also possible with Descovy.

Prior to starting therapy with Descovy, nurses should confirm that the patient has been tested for HIV-1 and is negative. Nurses should teach patients they need to be tested every three months while taking Descovy to confirm continued HIV-negative status. Nurses should also teach patients to practice consistent and correct condom use; use a water- or silicone-based lubricant with the condom; engage in less risky sexual practices, such as oral sex; be aware of partners' HIV-1 status, including viral suppression status; and undergo regular testing for sexually transmitted infections that can facilitate HIV-1 transmission. If the patient is an injection drug user, nurses should teach them never to share needles. Nurses can refer individuals who want to know more about decreasing their HIV risk to a customizable risk reduction tool from the Centers for Disease Control and Prevention (CDC; http://www.cdc.gov/hivrisk) or to the CDC site on basic HIV prevention information (http://www.cdc.gov/hiv/basics/prevention.html).

For complete prescribing information for Descovy, go to http://www.accessdata.fda.gov/drugsatfda_docs/label/2019/208215s012lbl.pdf.