One of the big concerns for European governments considering whether and how to make Truvada available as pre-exposure prophylaxis for HIV (PrEP) is the cost. The medication itself is expensive, and it also requires on-going support from medical providers. In many European countries these costs will be borne largely or entirely by state-funded health systems.
Studies have consistently found that to be cost-effective PrEP, needs to be used by those at the highest risk of acquiring HIV. How high? The World Health Organization suggests that giving PrEP to people in groups with an incidence of 3% per year would be cost effective, while estimates in the UK suggest a minimum incidence of 5%.
Although gay and bisexual men generally are at elevated risk of infection, not every gay or bisexual man is at equally significant risk of acquiring HIV. In the US, the Centers for Disease Control and Prevention recently estimated that about 1 in 4 sexually active HIV-negative gay and bisexual men would benefit from PrEP.
One of the most important results of the PROUD trial in the UK was that the men in the study who were not using PrEP had an extremely high incidence of 9%. The French IPERGAY trial also found that men in the control group had a high rate of incidence (6.75%). This meant not only that Truvada as PrEP was (yet again) confirmed to be extremely effective at preventing HIV, but, crucially, that both studies had been extremely successful at recruiting men at very high risk of acquiring HIV.
But these studies were relatively small, and it’s not clear that simply applying the same criteria used for participation in the studies on a wider scale will be as effective at targeting the right people, or what criteria will be appropriate in other countries. While people at the highest risk of infection have been shown to be the most motivated to seek out and use PrEP, cost-conscious health systems want to have an idea of where to draw the line for eligibility so that those at low risk of infection do not use resources that could benefit others more.
So how do health authorities make sure they can reach those at higher risk, that the people who most need PrEP get it first?
A recent study conducted at Barcelona’s BCN Checkpoint sexual health centre for gay and bisexual men attempted to identify factors that could be used to assess risk of infection and help identify who could benefit most from PrEP and who should be prioritised for access. NAM/aidsmap has an excellent write up of the study results that were presented at the recent European AIDS Conference. I won’t attempt to summarise the results but recommend reading through the article.
What’s impressive to me here is that a trove of existing data about men at elevated risk of infection was analysed to provide detailed evidence to inform the development of practical guidelines in a particular local context.
Specific and neutral criteria for eligibility for PrEP are important from a cost-effectiveness perspective, but such criteria also help provide a basis for providers to recommend PrEP to those who might not consider themselves candidates for PrEP. A study based on surveys conducted among men attending commercial sex venues in New York found that among men who met study criteria for being prescribed PrEP, 78 percent said they did not consider their risk high enough to warrant using PrEP.
While he focus on people at elevated risk of acquiring HIV makes sense from a fiscal perspective, it’s important to take care to avoid creating or enhancing stigmatising language about PrEP and its users. It’s very easy to imagine the relevant questions about sexual behaviours (number of partners, condom use, specific sexual practices) being asked in ways that reinforce shame and discourage honesty. Likewise if these discussions reinforce perceptions that people on PrEP are inherently “risky” “reckless” or “promiscuous” it could all too easily discourage people from seeking it.
Here in Ireland, the process of developing and implementing guidelines for the use of anti-retroviral medication to prevent HIV is just getting underway. There is a sexual health service here in Dublin that is in some ways similar to Barcelona’s Checkpoint, the Gay Men’s Health Service, and a fair amount of data is collected about the men who attend there. Unfortunately it never seems to be put to much use.
To its credit, the GMHS does issue annual reports each year, but the data in those reports is presented in a rather haphazard fashion and is inconsistent from year to year, making it impossible to independently observe trends. Other than the jumble of top-level statistics, no real attempt at analysis ever seems to be made. Perhaps with the new evidence-focussed efforts being initiated as part of the National Sexual Health Strategy some of that data might be accessed and put to greater use. I’m not holding my breath though.