This study aims to describe the safety, tolerability and adherence to the coformulated anti-HIV drug tenofovir-emtricitabine-rilpivirine (eviplera) when given to men who have sex with men (MSM) following an actual or potential sexual exposure to HIV. This biomedical intervention is known as nonoccupational post-exposure prophylaxis (NPEP). Patients receive NPEP if they meet the criteria outlined in the 2007 National Australian NPEP Guidelines. Three or two anti-HIV drugs are administered for 28-days depending on the severity of the the assessed HIV acquisition risk. In this study eviplera would constitute 3-drug NPEP. Tenofovir-emtricitabine (truvada) a component of eviplera has been used in NPEP at SVH since 2006.

This is a multi site, prospective, open-label, non-randomised trial. Participants will be MSM who present at the various recruitment sites requesting NPEP. Initially, 50 eligible participants will be assigned to receive eviplera 25mg once daily taken with food for 28-days according to established Australian guidelines for the use of 3-drug NPEP. There will be 7 visits over a 12-week period. Follow-up post NPEP is for 8 weeks. If an interim analysis demonstrates acceptable safety, it is proposed to seek ethics approval to increase the samples size to 100 patients to gain more accurate information on regimen completion rate and on-drug adherence.

The primary study objectives are:

1. To describe the safety of 28 days of NPEP using co-formulated FTC-RPV-TDF
2. To describe the tolerability of 28 days of NPEP using FTC-RPV-TDF
3. To describe on-drug adherence and regimen completion rates of 28 days of NPEP using FTC-RPV-TDF

Inclusion Criteria:

1. Man who has sex with men

2. Age at least 18 years

3. Eligible for 3-drug NPEP according to Australian guidelines for the use of 3-drug NPEP following an actual or potential sexual exposure to HIV or receptive anal intercourse with an unknown source

4. Able to provide written, informed consent

5. Able to commit to the study visits

   Exclusion Criteria:

6. Non-sexual exposure

7. Exposure occurring during sex between a man and a woman

8. HIV infection diagnosed on day 1 serological testing including indeterminate serology consistent with possible primary HIV infection

9. Use of any medication contraindicated with FTC-RPV-TDF

10. Serum hepatic transaminase (alanine aminotransferase [ALT] greater than 5 times the upper limit of the normal range

11. Serum estimated Glomerular Filtration Rate (eGFR) <60mL/min/ BSAc

12. Current therapy for hepatitis B

13. Day 1 serological evidence of chronic/active hepatitis B

14. Previous NPEP containing FTC-RPV-TDF

15. A patient with a history or current evidence of any condition, therapy, or laboratory abnormality, or other circumstance that might confound the results of the study, or interfere with the patient's participation for the full duration of the study