Intervention Research to Reduce HIV Sexual Transmission Among HIV Positive Men Who Have Sex With Men

The randomized control trial (RCT) component will test the efficacy of GPS, an HIV prevention intervention for HIV+ men who have sex with men (MSM). The present study is intended to be a rigorous evaluation, with the ultimate aim of testing the scale-up of the GPS program using a Phase IV effectiveness trial, per standard procedures for evaluating health interventions. The study hypothesis is that the study intervention will result in reduced prevalence of unprotected anal intercourse (UAI) acts among HIV+ MSM at 6-month follow-up with partners who are negative or of unknown HIV status. The secondary hypotheses are that the intervention will result in (1) reduced prevalence of UAI at 6-months follow-up with partners who are HIV+, and (2) a reduction in the number of sexual partners.

This is a 2-site, 2-arm, randomized controlled trial that will randomize 180 participants to either a 8 session group motivational interviewing intervention (GPS) starting within 2 weeks after randomization, or to a wait-list control group. For ethical reasons, participants randomized to the control group will have the option to attend a GPS session after a 6-month wait period. Participants will complete 8 sessions of a small-group sexual health intervention to reduce sexual risk behaviour. Assessments will be conducted prior to the 8-session group, at the completion of the sessions and at 3-month and 6-month follow up post-intervention. The wait-list control group will complete 3- and 6-month follow-up assessments during their waiting period as well as after completing their GPS session. The 6 month follow-up assessment during their waiting period will be considered to be the baseline measure for their GPS session. Participants in both groups will complete interviews at the end of the 8 sessions and at the 6-month follow up.

GPS takes the form of a small counseling group, since this is one of the most common intervention forms for similar populations. Participants will be organized into 15 groups per arm of approximately 6 participants, each of which will be led by 2 facilitators who are HIV+ MSM. This study builds upon a one-armed open-label Canadian Institutes for Health Research (CIHR)-funded grant that demonstrated that GPS is feasible to administer and appears to result in significant risk reduction. The study also showed that GPS results in promising reductions in UAI, thus forming a solid foundation for moving toward an RCT. In preliminary GPS data (n=25), we found a reduction in UAI from 88% at baseline to 60% at 3-month follow-up. More importantly for HIV prevention, we found a reduction in UAI with partners of HIV-negative or unknown HIV status from 56% at baseline to 36% at 6 month follow-up. Participants reported high satisfaction with the GPS program and our initial study site has found GPS to be highly feasible in their community organization.

The proposed study will provide data on the efficacy of a motivational interviewing behavioural intervention for HIV+ MSM. Although research among primarily American samples documents moderate effect sizes for HIV prevention interventions among MSM, none have found a significant effect of an HIV prevention intervention for HIV+ MSM in Canada, nor have any studies examined the effect of a small-group based intervention using HIV+ MSM peers who are trained to administer motivational interviewing for HIV+ MSM. Armed with the data from the present study demonstrating the efficacy of the intervention, we will design and implement the next stage of the research program, which will be a Phase IV study to examine the effectiveness of the intervention in Toronto, Vancouver, and at least 2 other sites serving HIV+ MSM in Canada.

The intervention should result in a decreased likelihood of having risky sex versus being on a waitlist. Previous data from formative research with this same intervention indicates promising findings that indicate a decreased prevalence of risky sex amongst GPS participants.