The FDA has given the green light to Descovy (emtricitabine 200 mg/tenofovir alafenamide 25 mg [F/TAF], Gilead Sciences), a fixed-dose combination for the treatment of human immunodeficiency virus-1 (HIV-1) infection. Descovy is indicated for use in combination with other antiretroviral agents in adults and pediatric patients 12 years of age and older. Descovy is not indicated for use as pre-exposure prophylaxis to reduce the risk of sexually acquired HIV-1 infection in adults at high risk.
The label for Descovy includes a boxed warning regarding the risks of lactic acidosis or severe hepatomegaly with steatosis, and post-treatment acute exacerbation of hepatitis B.
TAF is a targeted prodrug of tenofovir that has demonstrated high antiviral efficacy similar to and at a dose less than one-tenth that of Viread (tenofovir disoproxil fumarate [TDF], Gilead). TAF has also demonstrated improvement in surrogate laboratory markers of renal and bone safety compared with TDF in clinical trials in combination with other antiretroviral agents. Data have shown that because TAF enters cells, including HIV-infected cells, more efficiently than TDF, it can be given at a much lower dose, and there is 90% less tenofovir in the bloodstream, according to Gilead.
The approval of Descovy was supported by data from two pivotal phase 3 studies in which an F/TAF-based regimen (administered as Genvoya; elvitegravir 150 mg/cobicistat 150 mg/emtricitabine 200 mg/tenofovir alafenamide 10 mg [E/C/F/TAF], Gilead) met its primary objective of noninferiority compared with an F/TDF-based regimen (administered as Stribild; elvitegravir 150 mg/cobicistat 150 mg/emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg [E/C/F/TDF], Gilead) in treatment-naïve adults after 48 weeks of treatment. Tests of certain renal and bone laboratory parameters favored the F/TAF-based regimen over the F/TDF-based regimen.
The FDA’s decision was also supported by a phase 3 study evaluating an F/TAF-based regimen (administered as Genvoya) in virologically suppressed adults who switched from F/TDF-based regimens. In this study, the F/TAF-based regimen was found to be statistically noninferior to the F/TDF-based regimens and demonstrated improvements in certain bone and renal laboratory parameters compared with the F/TDF-based regimens.
In addition, the FDA’s approval of Descovy was supported by data from phase 3 studies evaluating an F/TAF-based regimen (administered as Genvoya) in virologically suppressed adults with mild-to-moderate renal impairment and in treatment-naïve adolescents.
Finally, bioequivalence studies demonstrated that Descovy achieved the same drug levels of TAF and emtricitabine in the blood as Genvoya.
Descovy does not cure HIV infection or acquired immune deficiency syndrome (AIDS).
Source: Gilead Sciences; April 4, 2016.