FDA Recommends Descovy for Use as PrEP
The Antimicrobial Drug Advisory Committee of the Food and Drug Administration (FDA) has recommended the approval for this new drug for use by men and transgender women who have sex with men.
Descovy, manufactured by Gilead Sciences Inc., is a pill designed to prevent HIV in an effort called pre-exposure prophylaxis, PrEP.2-3
Gilead’s goal of bringing Descovy to market is to reduce the risk of HIV transmission in populations at increased risk of acquiring the virus.1 The combination medication was granted FDA approval in 2016 for the treatment of chronic HIV.1 The combination, emitricitabine 200 mg and tenofovir alafenamide 25 mg tablets, are taken orally.
PrEP for HIV prevention
PrEP is an HIV prevention option. PrEP is only to be used by individuals who are currently HIV negative. The purpose of this medication approach is to help prevent HIV transmission from unprotected sex or intravenous drug use from an individual who is HIV positive.
How does PrEP work?
Pre-exposure prophylaxis involves taking a daily pill that may provide up to a 99 percent level of protection from acquiring HIV infection.1 It is highly effective when taken as prescribed. Although less effective when not taken consistently, it has been demonstrated that even people who take only take 2 PrEP pills per week achieved an estimated 76 percent level of protection.1
Descovy would be Gilead’s second HIV prevention pill on the market. Currently, their other brand Truvada (emtricitabine/tenofovir disoproxil fumarate) is the only FDA-approved treatment for PrEP.2
Clinical trials for Descovy as PrEP
The global Phase 3 clinical study, DISCOVER, evaluated the efficacy and safety of Descovy compared with Truvada. The trial results reported that Descovy achieved non-inferiority to Truvada.1 This means they were similar, no worse than the medication already on the market.1 Descovy demonstrated non-treatment related improvements in renal function and bone density level biomarkers in study participants.1,5 These results indicated less toxicity in the bones and kidneys than Truvada.3
Demographic representation in clinical trials
Some critics of the study suggested that although the demographics of the DISCOVER trial were reflective of current PrEP users, educated white men in their 30s, the study population did not represent the minority populations currently at highest risk of HIV infection.5
Safety of Descovy as PrEP
The trials suggest that Descovy was both safe and well-tolerated in the population that was not HIV positive. Nausea was the most common adverse reaction, occurring in about 10 percent of the population.2 There was, however, a higher incidence of elevated fasting lipids in people taking Descovy, requiring the taking of lipid-lowering medications.5 On the positive side, Descovy remained in the body longer than Truvada, providing a protective effect even after the medication is stopped.
Concerns about cost
Patient advocacy groups have raised questions about the cost of Descovy for PrEP.3 High cost could be a barrier to access.3 Many insurance companies do not presently cover Truvada, because they see it as HIV treatment and not as a prophylactic medication. At $1,675 a month, around $20,000 a year, the medication can be out of reach for those without insurance coverage. Beginning in 2020, there will be a cheaper generic version of Truvada available.2-3
Indication for Descovy as PrEP
The FDA review of trial data was not without controversy. The panel did not support a broad indication for Descovy because of a lack of data about the drug's effectiveness in women.
Cis-gender women were not part of the DISCOVER study. Cisgender describes those whose sense of gender matches their gender at birth.6 Therefore, there was no clinical trial data available to support an indication for the use of Descovy as PrEP in cisgender women. Nor was there any trial data on adolescents.3,5
If Descovy is only approved for HIV prevention in study populations, women could still use Truvada for prophylaxis. The discussion centers around whether women should have access to new medications based on quality data surrounding the safety and efficacy testing of drugs – in the same way that men have.6
How often does someone offer you unsolicited advice on your health?