Partner Services Pre-exposure Prophylaxis (PS-PrEP)

The investigators will enroll 150 human immunodeficiency virus (HIV) seronegative contacts presenting to sexually transmitted infections (STI) clinics for HIV testing and referrals from the Chicago Center for HIV Elimination (CCHE) network-based projects, ages 18 - 35, in this study over a period of 18 months referred from University of Chicago clinics and outreach space that perform HIV Partner Services as well as Expanded HIV testing and Linkage to Care (XTLC) and Chicago Department of Public Health (CDPH) partner notification services on the South Side of Chicago.

Eligible participants will undergo consent and complete the baseline assessment within 14 days of eligibility. Subjects will be taken through the baseline assessment includes survey modules described in detail below (demographics, substance use, mental health and stigma). At the baseline visit, the investigators will collect data on demographics and sex and drug-using risk variables. From the common electronic medical record at both clinics, the investigators will collect data on participants' care providers and health care utilization. Subjects will be asked to sign a medical release form.

Whenever possible, the investigators selected measures: (1) previously tested in HIV implementation studies, particularly among younger and minority populations and (2) to maximize comparability to other studies.

Randomization Following the baseline assessment, study participants will be randomized into one of two groups: the Partner Services Pre-exposure Prophylaxis (PS-PrEP) intervention group or the standard of care practice PrEPLine control condition. Study staff will discuss pros and cons, ethical basis of assigning participants to different arms of a study, of control and intervention with participants (equipoise induction) to balance the desirability of the two intervention conditions. Block randomization will be used for allocation to ensure balanced representation in the two treatment arms (control and intervention) as recruitment progresses. The randomization assignment will be generated using the R program. Once randomized, each participant will be given a study identification number and will be allocated to their respective study condition to begin the trial. Due to the nature of this intervention, complete masking of participants, investigators, and interventionist is not possible. The research staff will work directly with the linkage and support group. To help mitigate possible bias in interviewing, baseline data collection will occur prior to randomization.

After randomization, those who are in the intervention group will be taken through the Session I of the intervention. This may take place on the same day as the consent and baseline visit, or it may be scheduled at a different time depending the subject's availability.