{
  "abstract": "Background DoxyPEP has demonstrated high effectiveness against bacterial sexually transmitted infections (bSTI); however, its utilisation among PrEP users in everyday clinical practice remains unclear. Aims of this study were to: (i) describe the characteristics of individuals who chose to use doxyPEP, (ii) explore the contexts in which it is most frequently used, and (iii) describe its real-life safety, tolerability, and efficacy.Methods This retrospective analysis included all individuals with at least two visits between January 2024 and September 2025 to a community-based service providing free medical assistance to PrEP users. Participants were prescribed doxyPEP, with recommendations for its use specifically during sexual exposures involving a high number of partners within a short timeframe. Descriptive and nonparametric statistics were used to characterise the study population. Logistic regression was applied to identify individual and behavioural factors associated with doxyPEP uptake. Poisson regression was used to evaluate its effect on bSTI incidence.Results The study included 975 individuals, representing a total of 4,187 visits; 382 of these individuals reported using doxyPEP at least once ( table 1). The median number of doses administered between visits was 2 (IQR 1-3). The majority (92.9%) adhered to the prescribed schedule. Factors associated with doxyPEP use were chemsex (aOR 2.18, 95%CI 1.63-2.90), years on PrEP (aOR 1.17, 95%CI 1.12-1.23), and a higher number of sexual intercourses (aOR 1.06 per 10 more, 95%CI 1.03-1.08). DoxyPEP was primarily used during groupsex (57.1%) and when attending cruising venues (48.6%). Adverse events were uncommon (13.9%), predominantly gastrointestinal (93.0%). After adjusting for age, chemsex use, and number of sexual intercourses, the effect of doxyPEP on the risk of bSTIs acquisition was not protective (IRR 1.15, 95%CI 1.05-1.26).Discussion In our population, doxyPEP was utilised by individuals at significant risk of exposure for a limited number of sexual encounters. Although employed in high-risk contexts, it did not demonstrate a protective effect, likely due to the infrequent use and to risk compensation issues. Substantial efforts regarding counselling and prescription are required to achieve a significant protective effect at both the individual and population levels.Abstract OC30 Table 1Demographic, clinical, and behavioral features of study population",
  "authors": [
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy"
      ],
      "name": "E Caruso"
    },
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy",
        "San Raffaele Scientific Institute, Milan, Italy"
      ],
      "name": "C Muccini"
    },
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy"
      ],
      "name": "P Russo"
    },
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy",
        "ASST Santi Paolo e Carlo, Milan, Italy"
      ],
      "name": "A De Bona"
    },
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy",
        "ASST Fatebenefratelli-Sacco, Milan, Italy"
      ],
      "name": "D Moschese"
    },
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy"
      ],
      "name": "N Frattini"
    },
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy"
      ],
      "name": "L Nekrasova"
    },
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy",
        "ASST Santi Paolo e Carlo, Milan, Italy"
      ],
      "name": "D Tesoro"
    },
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy",
        "ASST Fatebenefratelli-Sacco, Milan, Italy"
      ],
      "name": "V Iannone"
    },
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy"
      ],
      "name": "P Vinti"
    },
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy"
      ],
      "name": "M Cernuschi"
    },
    {
      "affiliations": [
        "Milano Checkpoint ETS, Milan, Italy",
        "ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy"
      ],
      "name": "R Rossotti"
    }
  ],
  "title": "OC30 DoxyPEP remains underutilised to exert its full protection: data from a cohort of PrEP users",
  "uid": "23f3d27f-4145-54ba-977b-be33a3ac1ae8"
}