Table 1Risk-benefit table

FactorExplanation / EvidenceJudgment
Quality of EvidenceOne multi-country RCT without serious limitations. Additional studies from other populations at various stages of completion.High
Balance of Benefits vs. HarmsHIV infection
Oral PrEP was associated with reduced risk of HIV in both intention-to-treat analysis (HR: 0.53, 95% CI 0.36-0.78, p=0.001) and modified intention-to-treat analysis (HR: 0.56, 95% CI 0.37-0.85, p=0.005).

Adverse events
There was no significant difference in reported adverse events between the FTC-TDF and control arms for either any adverse event (RR: 0.99, 95% CI 0.94-1.04) or grade 3 and 4 adverse events (RR: 0.92, 95% CI 0.75-1.13). Preliminary analyses from ongoing studies show no major differences in adverse events across treatment and control groups.

Condom use
Both the FTC-TDF and control study arms reported increased condom use (defined as the percent of partners using condoms during receptive intercourse) from baseline to follow-up over the course of the study; however, there was no significant difference in condom use rates between study arms over time (p=0.36).

Number of sexual partners
Both the FTC-TDF and control study arms reported reduced number of receptive sexual intercourse partners from baseline to follow-up over the course of the study; however, there was no significant difference in the reported number of sexual partners between study arms over time (p=0.97).
Benefits outweigh harms
Values and PreferencesStudies examining MSM-TG knowledge and attitudes towards PrEP have been conducted in several settings. U.S. studies report increasing awareness of PrEP among MSM over time. Between 44% and 74% of MSM said they would consider taking PrEP themselves across studies. Positive aspects of PrEP include user-friendliness and potential benefits for use in serodiscordant relationships. Concerns include potential side-effects, potential sexual risk disinhibition, stigma and discrimination associated with PrEP use, and mistrust of healthcare professionals. Factors affecting PrEP acceptability included efficacy (most studies were conducted before iPrEx trial results), potential side-effects and out of pocket costs.Acceptable to many MSM- TG
ResourceUseOne cost-effectiveness study from Australia estimated that if continuous PrEP was 90% effective and the program covered only HIV-negative MSM having high risk sex, it would cost $47,745 per quality adjusted life year (QALY) gained (Anderson & Cooper, 2009).

Another cost-effectiveness study found PrEP to be cost-effective under 75% of the 80 scenarios tested at a threshold of US$50,000 per QALY gained (Desai et al. 2008).

Another cost-effectiveness study from the USA estimated that if PrEP was 90% effective and the program covered only HIV-negative MSM having high risk sex, it would cost US$107,000 per QALY gained. If PrEP was 50% effective, it would cost US$298,000 per QALY gained. Sensitivity analyses showed that the cheaper and more efficacious PrEP is and the more high risk the population, the more cost-effective it will be, with a range of estimates from cost-saving to over US$300,000 per QALY saved (Paltiel et al., 2009).

Cost-effectiveness estimates vary widely depending on model parameter estimates, including efficacy, cost of PrEP, and HIV incidence and age of the target population. Results range from being cost-saving to costing over US$300,000 per QALY saved.
Consideration in certain settings
FeasibilityOral PrEP for MSM has proven feasible in various trial settings. Issues of criminalization, stigma and discrimination, and violence should be considered during implementation, especially where MSM-TG behavior is illegal.Consideration in certain settings

From: Annex 4, Pre-exposure prophylaxis (PrEP) for men and transgender women who have sex with men (MSM and TG): a systematic review

Cover of Guidance on Pre-Exposure Oral Prophylaxis (PrEP) for Serodiscordant Couples, Men and Transgender Women Who Have Sex with Men at High Risk of HIV
Guidance on Pre-Exposure Oral Prophylaxis (PrEP) for Serodiscordant Couples, Men and Transgender Women Who Have Sex with Men at High Risk of HIV: Recommendations for Use in the Context of Demonstration Projects.
Geneva: World Health Organization; 2012 Jul.
Copyright © 2012, World Health Organization.

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