- The Food and Drug Administration has greenlit another Gilead drug to prevent HIV infections, granting it a broad label that includes adults and adolescents at risk of sexually acquiring the disease.
- Regulators didn't, however, approve Gilead's Descovy for cisgender women at risk of contracting HIV through vaginal sex. The company had been pushing for that group to be included on the drug's label, arguing that data from a study of cisgender men and transgender women who have sex with men could be extrapolated.
- Until Thursday, Gilead's Truvada was the only pill approved for HIV pre-exposure prophylaxis, or PrEP. The drug could face generic competition as early as next year, providing an incentive for Gilead to transition patients onto Descovy to protect a $2 billion revenue stream.
It's unclear whether Descovy (emtricitabine/tenofovir alafenamide), which was previously approved to treat patients with HIV, will increase PrEP use with its expanded label.
Of the 1.2 million U.S. patients eligible for HIV PrEP, RBC Capital Markets estimates 200,000 are actually receiving it. Access to preventative HIV drugs has been a challenge for many of them due to cost and insurance barriers. The list prices for Descovy and Truvada (emtricitabine/tenofovir disoproxil fumarate) were each $1,758 per month.
One group of particular concern for healthcare providers is women. The Centers for Disease Control and Prevention says women comprised 19% of the 38,739 new HIV diagnoses in 2017; yet, according to estimates from Jefferies, they account for less than 7% of PrEP use.
At an August meeting with one of the FDA's advisory committees, some Descovy for PrEP advocates argued that excluding cisgender women from the drug's label could put the group's health at greater risk.
Gilead didn't provide data on cisgender women in its Descovy for PrEP approval application, something that frustrated committee members. "We have failed women," Committee Chairperson Lindsey Baden, an infectious disease physician, said during the meeting. "To be at this point and not have the data to guide decision-making is a shame on all of us."
The committee ultimately voted 10 to 8 against recommending approval in cisgender women, citing the lack of data. Gilead representatives at the time said the company was committed to running Descovy for PrEP trials in cisgender women, regardless of the approval outcome.
Conversely, the committee was almost unanimous on Descovy for PrEP's use in men and transgender women, voting 16 to 2 in favor of clearing the drug for those patients at high risk of contracting HIV. The vote hinged on data from DISCOVER, a Phase 3 study that enrolled 5,400 of these patients and found Descovy was non-inferior to Truvada in preventing HIV infection.
Notably, 99% of the DISCOVER participants were men, which the committee said made it difficult to evaluate Descovy for PrEP in transgender women.
While the FDA isn't bound to follow advisory committee recommendations, it usually does. Wall Street analysts therefore anticipated Descovy for PrEP's approval to shake out the way it did.
They now expect Gilead's focus will be switching PrEP patients from Truvada to Descovy before the former goes generic.
Opponents of Descovy for PrEP have argued that Gilead is seeking approval because of business interests, not patient needs. They have highlighted how one of Descovy's active ingredients is nearly 20 years old, and say they're worried Gilead will market the drug as superior, rather than non-inferior, to Truvada, which could influence doctors' prescribing decisions and lead to higher costs for patients.