A large, in-depth look at US patients taking HIV-prevention drug therapy found strong adherence soon after patients get the prescription, but less consistent use thereafter, particularly among groups considered to be high-priority.
The study, published in JAMA Network Open, examined data from 13 906 members of Kaiser Permanente referred for pre-exposure prophylaxis, or PrEP, therapy between 2012 and 2019. The study found certain groups were more likely to stop taking PrEP: young people, Black and Latino individuals, women, and people with substance use disorders.
The findings suggest targeted strategies are needed to support use of this effective prevention in high-risk groups, said lead author Carlo Hojilla, RN, PhD, a research fellow with the Kaiser Permanente Northern California Division of Research.
“The findings have important implications that suggest access to health care is a great way to get people in the door, but we need more effective strategies for making sure people who have an ongoing need for PrEP stay on the medication,” said Dr Hojilla. “These are groups we want to reach, and we need innovative approaches to keep them engaged in PrEP care.”
Some 88% of patients referred for HIV prevention care received a PrEP prescription, and most (98%) of them filled their initial prescriptions. “These findings were encouraging,” Dr Hojilla said. “Kaiser Permanente has managed to do really well increasing uptake of PrEP therapy.”
However, significant inconsistency in use was seen with about half of users discontinuing PrEP at least once; 60% of those filled a prescription again though the study did not explore the reasons for this. Some users may have discontinued PrEP because of a decrease in risk for HIV acquisition, the authors speculated. Medical mistrust, stigma, homophobia, and transphobia as barriers to PrEP uptake and persistence in some communities have been documented in prior studies. Cost was known to be a concern for some, and the study was done before PrEP was provided at no cost, Dr Hojilla said.
The study was also done before the introduction of a new dosing scheme known as 2-1-1, or on-demand, which allows the user to take PrEP only around the time of a potential exposure to HIV, with a similar level of effectiveness as daily dosing. It’s possible that some of the discontinuation reflected in the study was from patients who opted to not take the drug daily because they had only occasional risk exposure, even prior to 2-1-1 dosing being formally recommended, said senior author Jonathan Volk, MD, an infectious disease specialist with The Permanente Medical Group.
No new HIV infections were seen in those remaining on PrEP, the study found. “This shows how incredibly well PrEP works when taken,” Dr Volk said. “But there are important opportunities for us to maximise the population level impact of this vital therapy. To do this, we need to avoid attrition along the care continuum, especially by assisting patients to stay on PrEP throughout periods of risk for HIV acquisition.”
Source: Kaiser Permanente