Conditional Economic Incentives Could Be Effective in Improving Adherence to Long-Acting PrEP in Transgender Adults

Young adults in Washington state who identified as transgender were incentivized to continue using pre-exposure prophylaxis (PrEP) when offered prescriptions for injectable hormones during in-person care visits and cash incentives, according to a study published in Medical Decision Making.1

Cash incentives and prescriptions to injectable hormones can help increase adherence to PrEP in transgender adults. | Image credit: Olga Tsikarishvili - stock.adobe.com

HIV was diagnosed in 36,801 individuals living in the US in 2019, of which 671 were among transgender people, making it a prevalent subgroup to curb incidence of HIV.2 PrEP is a means of preventing the spread of HIV but adherence needs to be high in order to curb the incidence of the virus. Adherence in transgender individuals has been lower than needed to prevent HIV in this population, with only 32% of transgender women without HIV using PrEP despite 92% knowing about the treatment. Conditional economic incentives may be able to increase adherence in this population and help them engage in treatment. This study aimed to use a discrete-choice experiment to figure out which factors mattered when it came to increasing adherence to long-acting injectable PrEP (LA-PrEP) in transgender adults who are HIV-negative.1

The Washington Priority Assessment in Trans Health Project was used to embed the discrete-choice experiment. Participants had to be self-reported transgender and/or nonbinary, older than 18 years, and living in Washington state. All participants completed a survey that collected data on demographics, administered the experiment, and collected data on health care experiences and needs.They received a gift card for completing the survey.

The experiment included 5 attributes of 3 levels each to assess the amount of incentive to get high LA-PrEP adherence, the format of the incentive, the method of incentive, the hormone prescription type given during the visit for LA-PrEP, and counsel to increase adherence. Participants were asked to choose between hypothetical options for each attribute, including the amount of cash incentive and the means of testing the level of adherence.

There were 385 participants in the study who had a mean (SD) age of 29 (4.1) years and the majority were White (62.9%). A total of 99% of the participants were covered by health insurance but 79.2% had not taken PrEP. Annual income was less than $50,000 for more than half of those who responded to the survey.

Participants had a positive response to yearly incentives, with a positive coefficient of 0.013, with the increase of incentive increasing the probability of choosing an intervention program. Electronic cash card was the preferred method of receiving the incentive, with a coefficient of 0.090. Injectable hormones were the preferred coprescription over oral hormones or no prescription at all should the participants come in for their LA-PrEP. All participants preferred blood testing for measuring their adherence rather than blood and hair testing, and they preferred to receive counselling in person.

The maximum yearly incentive would be $1200. Participants were willing to part with $547 to receive a coprescription for injectable hormones, $112 to confirm adherence through blood test, and $689 to get a cash incentive rather than a voucher. Participants younger than 38 years chose the option for no incentive program less often than other age groups.

Programs that provided incentives for free gender-affirming care and LA-PrEP had a probability of being chosen of 45% in young adults who are transgender, but the probability decreased in adults who were older and had more income. This indicates that programs with cash incentives should be aimed toward individuals who are younger and less economically stable compared with older adults.

There were some limitations to this study. Pilot testing was limited in individuals who were not affiliated with the research, and specificity could have been lacking when participants were asked to make choices. All participants were from the Pacific Northwest and were primarily White, which could limit generalizability, and the sample having a preference to receiving hormone therapy may not be representative of all transgender people in the US. Also, time and effort are needed for participants to complete the experiment, and randomized controlled trials will be needed to confirm the finding.

The authors concluded that cash incentives and offering prescriptions for injectable hormones could help to increase adherence to PrEP in transgender young adults in the US. “Findings from this [discrete-choice experiment] can help already committed decision makers allocate available funding to programs that have the greatest likelihood of success,” the authors concluded.

References

1. Wilson-Barthes MG, Restar AJ, Operario D, Galárraga O. Incentivizing adherence to gender-affirming PrEP programs: a stated preference discrete-choice experiment among transgender and gender nonbinary adults. Med Decis Making. Published online August 16, 2025. doi:10.1177/0272989X251355971

2. Fast facts: HIV and transgender people. CDC. March 28, 2024. Accessed August 18, 2025. https://www.cdc.gov/hiv/data-research/facts-stats/transgender-people.html