
While some countries have already shifted to less intensive monitoring requirements for PrEP users, a Dutch study has now provided evidence that it’s OK to test for sexually transmitted infections (STIs) every six months, to have clinic appointments at the same rhythm and for services to be delivered online. Simplified, less burdensome services had just as good outcomes as the standard of care. (In research terminology, they were ‘non-inferior’.)
The latest data were presented by Marije Groot Bruinderink of the Public Health Service of Amsterdam at the Conference on Retroviruses and Opportunistic Infections (CROI 2025) last week. The findings on testing for STIs were presented last summer at AIDS 2024 in Munich.
The EZI-PrEP study recruited 469 PrEP users – 99% were gay and bisexual men, their median age was 36, 68% were born in the Netherlands, 81% were university educated and 19% had a bacterial STI at baseline.
They were randomly allocated to one of four types of service delivery:
- In-person monitoring at a sexual health centre every three months (the standard of care)
- In-person monitoring every six months
- Online monitoring every three months
- Online monitoring every six months.
The online service involved the user providing some medical and behavioural information on a phone app; visiting a high-street or hospital laboratory for testing of HIV, STIs and kidney function; having a video consultation with a clinician (optional after the first six months); and receiving their PrEP tablets at a pick-up point or by post.
For the purposes of the study, participants were asked each day to respond to questions on a phone app about whether they had taken PrEP, had anal sex with a casual partner and used condoms. This allowed the researchers to measure the study’s primary outcome, which was the number of unprotected sex acts (i.e. condomless anal sex, not covered by PrEP, with a casual partner).
With a little over one year of follow-up per participant, there was an average of 1.3 unprotected sex acts per year per participant. This figure was slightly lower in those receiving online monitoring, but similar between those monitored every three or six months. In other words, the outcomes were ‘non-inferior’.
One of the study’s secondary outcomes was the incidence of STIs. An analysis presented last summer compared incidence according to the frequency of monitoring (but not according to whether it was in-person or online).
STIs were detected at 29.1% of visits in the six-monthly arm and at 25.6% of visits in the three-monthly arm, a difference that was not statistically significant. For asymptomatic STIs specifically, there was a slightly higher rate in the six-monthly arm (27.0% vs 22.5%, p=0.038).
In addition to scheduled visits, PrEP users could attend a sexual health centre at other times – for example, if they had symptoms of an STI. PrEP users monitored every six months had more additional STI visits (274) than those monitored every three months (157), but had fewer visits overall (862 vs 1288).
The researchers say that more frequent, face-to-face appointments add to the burden for PrEP users and costs for health services. Their findings suggest that simplified services don’t have negative impacts in relation to taking PrEP when it’s needed or the incidence of STIs.
Groot Bruinderink ML et al. Online and Less Frequent Monitoring of Oral HIV PrEP Use Are Noninferior to Standard of Care. Conference on Retroviruses and Opportunistic Infections, San Francisco, poster 1206, 2025.
View the abstract on the conference website.
Download the poster from the conference website.
Groot Bruinderink ML et al. STI testing rates among PrEP users randomized to 3-monthly (standard of care) or 6-monthly monitoring within the EZI-PrEP trial, the Netherlands: preliminary results. 25th International AIDS Conference, Munich, abstract OAE3902, 2024.