In the nine months since the Food and Drug Administration approved Descovy for pre-exposure prophylaxis (PrEP), more than one in three people who began PrEP did so using Descovy, according to data presented at the virtual Conference on Retroviruses and Opportunistic Infections 2021 (CROI).   

That appears to mean that Descovy (tenofovir alafenamide/emtricitabine) is on track to make up 45% of PrEP market share in 2020, approaching that of Truvada (tenofovir disoproxil fumarate/emtricitabine).

This comes despite continued pushback from activists and providers who have challenged Gilead Science’s patents, its timing strategy for releasing Descovy, its price and even the claim that Descovy is safer than Truvada for PrEP. Among people on HIV treatment, tenofovir alafenamide (TAF) is less likely than tenofovir disoproxil fumarate (TDF) to cause kidney and bone problems; it is unclear whether this is also the case for people on PrEP. 

In the data released at CROI, Karen Hoover, MD, of the Centers for Disease Control and Prevention, and colleagues analyzed data from retail pharmacies reporting to the IQVIA database. The database comprises data for more than 90% of retail pharmacies. The researchers looked at prescriptions for Truvada and Descovy PrEP from 2014 through September 2020.

Just 27% of people on PrEP were using Descovy at the beginning of 2020, three months after the Food and Drug Administration (FDA) approved the combination pill for people having anal sex. By June 2020, 36% of people who started PrEP did so using Descovy.

Meanwhile, 29% of those already taking Truvada for HIV prevention switched to Descovy by September 2020. Truvada became available as a generic in October 2020.

Those who switched to Descovy from Truvada were more likely to be older, three times as likely to be men and more likely to live outside the Northeast (an area where clinicians and activists have been pushing hard against the new version of PrEP). People living in the South were 56% more likely to switch to Descovy, for instance, while people in the Midwest were 17% more likely to switch to Descovy from Truvada than their Northeastern counterparts.

People were less likely to switch if they were paying cash or using a payer other than public or private insurance for their PrEP drugs—29% and 43% less likely than privately or publicly insured people, respectively.

“New patented and generic PrEP drugs will become available in upcoming years in the United States,” the researchers noted. “Ongoing monitoring can help understand implications for U.S. health care expenditures.”

Click here to read the study abstract.
Click here to learn more about the differences between TDF and TAF.