Men who have sex with men (MSM) can successfully take pre-exposure prophylaxis (PrEP) only during the short period surrounding and during a vacation, a recent study shows.

Researchers at the University of Pittsburgh Graduate School of Public Health, The Fenway Institute in Boston and Harvard University sought to determine the feasibility of prescribing PrEP to MSM with instructions to start taking the daily pill regimen seven days before leaving for vacation and to conclude the regimen seven days after returning home.

Previous research has found that gay, bisexual and other men who have sex men are more likely to contract HIV while traveling or on vacation, after moving to a new city or following a breakup.

The central question of the study was the degree to which the men adhered to the daily regimen. This study used Truvada (tenofovir disoproxil fumarate/emtricitabine) as PrEP. In 2019, Descovy (tenofovir alafenamide/emtricitabine) was also approved as HIV prevention for MSM.

As described in the Journal of Acquired Immune Deficiency Syndromes, the investigators enrolled 54 MSM in Pittsburgh and Boston. Before prescribing PrEP, the researchers provided the participants with a brief counseling session to introduce them to this form of HIV prevention.

Forty-eight of the men attended the scheduled study visit three months following their vacation and were included in the study’s analysis. Directly after returning from vacation, 94% of these men had concentrations of tenofovir—one of the two drugs in Truvada—in their blood that were consistent with daily use of the pill.

Nearly three quarters of the men reported engaging in condomless sex during vacation, and about one in three reported using recreational drugs during that time.

None of the men contracted HIV while on vacation. However, one man contracted the virus during the three months following his return home following a lapse in his continued access to PrEP due to the loss of his health insurance and his relocation to a new city.

Seventy percent of the men said they were interested in continuing on PrEP long-term.

The study is limited by the fact that the participants were all very motivated to participate. The researchers did not address key questions about providing short-term access to PrEP in real-world settings, including whether physicians would feel comfortable writing abbreviated PrEP prescriptions for use during vacations. Nor did they examine the impact of the study’s brief counseling session about PrEP.

“We started this as a feasibility study to see if we could identify barriers to short-term PrEP use and make adjustments. But we were excited when we got the results and discovered that almost all the participants were adherent to the point of protection against HIV,” the study’s lead author, James Egan, PhD, MPH, an assistant professor of behavioral and community health sciences at Pitt Public Health, said in a press release. “This gives us a promising strategy to pursue in engaging at-risk men in HIV prevention efforts that work for them.”

“That really stood out to us,” added senior author Kenneth Mayer, MD, medical research director at Fenway and a professor of medicine at Harvard. “It shows us that introducing short-term use of PrEP before a vacation could lead to longer-term use. This presents an enticing opportunity to reduce HIV transmission.”

To read the study abstract, click here.

To read a press release about the study, click here.

To learn more about PrEP, click here.