Nested within the SwissPrEPared Program, the "SwissPrEPared Study" - a large, multicentric, nation-wide cohort study - aims to longitudinally follow individuals asking for PrEP prescription over a period of 3 years.

The main aims of the study will be:

1. To obtain epidemiological data on individuals asking for PrEP in Switzerland. We are particularly interested in:

   • Determining the extent of PrEP use in Switzerland;
   • Assessing and monitoring the occurrence of sexually transmitted infections (STIs) in this particular population.

2. To assess sexual health and sexual well-being in individuals asking for PrEP using a questionnaire specifically designed for the SwissPrEPared program.

Inclusion Criteria:

• Participation in the SwissPrEPared program
• Aged ≥16 years
• HIV negative

Exclusion Criteria:

• Individuals unable to follow program procedures (e.g. language barriers, mental or psychiatric disorders)

All individuals aged >16 years asking for PrEP prescription at one of the participating centers will be asked to participate to the SwissPrEPared study (consecutive ongoing recruitment). Only HIVnegative individuals will be deemed eligible. Participants for whom PrEP is not indicated or individuals declining PrEP will still be offered to participate in the study.

Individual participant data that underlie the results reported in the study protocol (including the statistical plan) will be available after de-identification of participants following article publication. Data will be provided to investigators whose proposed use of the data has been approved by the study team and the Scientific Board of the Swiss HIV Cohort Study. Proposals should be directed to jan.fehr@usz.ch.