Inclusion Criteria:

• All individuals with documented initiation of oral PrEP (daily or event-driven regimens), who have collected the medication at least once and have taken at least one pill, will be included in the study.

The approved criteria for the use of oral PrEP in Spain, as recommended by the Spanish Gesida guidelines (GeSIDA. Recomendaciones sobre la Profilaxis Pre-Exposición para la Prevención de la Infección por VIH en España. Marzo 2023. Available at http://.gesida-seimc.org/category/guias-clinicas/otras-guias-vigentes/), are as follows:

• People without HIV infection at the time of cohort inclusion
• Age ≥ 16 yr who meet the following criteria:
• MSM and transgender women with at least two of the following criteria during the last year: > 10 sexual partners; Condomless anal sex; Chemsex; PEP; ≥ 1 STI
• Sex worker women who report non-habitual use of condoms.
• Cisgender males/females, who report condomless and present at least two of the same criteria as MSM and transgender.
• PWID with unsafe injection practices

Exclusion Criteria: none

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