PrEP

PrEP2 – Crossover study

Attention: PrEP2 study has ended. Interested person may contact ceidstudy@cuhk.edu.hk for updates on new projects.

Aim and objectives

The project aims to explore the usage patterns and related determinants of on-demand versus daily mode of PrEP in MSM with substantial risk of HIV infection.

The objectives are, to:

1. compare the adherence to PrEP and associated protection of sex acts between on-demand and daily mode of delivery
2. examine the preferred mode of PrEP before and following exposure to periods of two modes of delivery
3. characterise pattern of risk compensation following PrEP
4. project transmission dynamics of HIV infection under the influence of different modes of PrEP delivery

The Joint Chinese University of Hong Kong – New Territories East Cluster Clinical Research Ethics Committee has approved this study (Ref. No.: 2016.719) and is authorised to access the participants’ records related to the study for ethics review purpose. For enquiry regarding clinical research ethics, please contact the Committee at crec@cuhk.edu.hk and phone at 2632 3935.

Study design

Participants will be followed up for a total of 50 weeks. PrEP will be prescribed to participants free. For half of the participants, a 16-week course of daily PrEP will be provided, followed by another 16 weeks of on-demand treatment. For the other half of the participants, the sequence is reversed. Participants begin with on-demand PrEP for 16 weeks then switch to daily PrEP in the remaining 16 weeks. All participants are asked to visit the clinic regularly for body check-up, HIV and STI tests, complete questionnaire and collect prescription. At week 50, participants will be contacted for follow-up questionnaire.

Eligibility criteria

To join the study, you must:

1. be male, aged 18 or above, and had anal sex with another man, with the most recent sex act in the last 6 month; and
2. normally reside in Hong Kong; and
3. be inclined to have unprotected anal sex in the coming months; and
4. be HIV negative (HIV antibody test negative within last 3 months); and
5. be HBsAg negative; and
6. have normal renal function

Flow chart of the study

Body check-up & tests:

• Renal function
• HBsAg
• HIV
• Syphilis, NG/CT

Urine and other samples will be collected.
Fingerprick rapid tests will be performed.