Italian
Rome, August 13, 2026. The National Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCS in Rome has presented new evidence on the use of PrEP (Pre-exposure Prophylaxis) at the 26th International AIDS Conference in Rio de Janeiro.
The two scientific works – dedicated respectively to adherence to PrEP and its continuity over time – were conducted and presented by Dr. Valentina Mazzotta.
The two analyses of the EPI-PrEP study, conducted on the Italian multicenter cohort PrIDE, provide a snapshot of PrEP usage in Italy during a phase characterized by the expansion of prevention options. In fact, alongside the now reimbursable oral PrEP, the long-acting injectable formulation, long-acting PrEP, has also been introduced.
“PrEP – explains Dr. Mazzotta – is one of the most effective available tools for preventing HIV infection. However, for the preventive strategy to fully express its potential, both correct adherence and continuity of prophylaxis over time play a central role.”
The EPI-PrEP study is a retrospective epidemiological analysis that involved 1,298 PrEP users enrolled between 2024 and 2025 in the Italian multicenter observational cohort PrIDE, with at least one follow-up visit after the start of prophylaxis.
The analyzed population was predominantly composed of cisgender men, with a median age of 39 years, while about one in four participants was experiencing PrEP for the first time.
The analyses presented at AIDS 2026 evaluated two complementary aspects: on one hand, the risk of PrEP interruption, and on the other, the likelihood of suboptimal adherence (i.e., use of PrEP not fully compliant with the prescribed regimen), comparing different administration schedules.
The discontinuation rate was 33.8% for daily oral PrEP, 24.5% for on-demand PrEP, and 29.8% among those who modified their dosing schedule during the considered period. The lowest value was observed among users of long-acting injectable PrEP: 6.3%. A lower likelihood of discontinuation was also observed among individuals followed in community-based centers compared to the hospital setting.
The second study presented by Dr. Mazzotta analyzed the ability of individuals to correctly follow the prescribed PrEP regimen. The estimated cumulative probability of suboptimal adherence after one year was 34.6% in the overall population. However, in this case as well, statistically significant differences were recorded among the various administration schemes: 54.9% for daily oral PrEP, 22.6% for on-demand PrEP, 22.3% for those who switched administration methods, and 9.4% for users of long-acting injectable PrEP.
“The two studies – Mazzotta further explains – indicate how the mode of administration can represent one of the elements associated with the ability to correctly follow and continue over time the prevention pathway. Long-acting injectable PrEP has been associated with a lower likelihood of suboptimal adherence and a lower likelihood of discontinuation among the analyzed regimens. Thus, it appears to be a more functional and effective approach. However, it is important to clarify the importance of not adopting a one-size-fits-all approach to HIV prevention. Differentiated and person-centered pathways are necessary, along with targeted strategies to promote adherence and retention in PrEP programs, in order to maximize its preventive impact in the long term.”
