While clinical trials have demonstrated the efficacy of
treatment as prevention, pre-exposure prophylaxis and vaginal microbicides,
researchers and policy makers lack clarity on the conditions that affect the
effectiveness of these strategies in the ‘real world’. Local factors, such as available resources, affected populations, the wider health system and the
cultural context are crucial but poorly understood,
according to stakeholders.
“Looking at the exact same data and reports, stakeholders in
India, South Africa and the US often came to very different conclusions about
their implications and relevance”, say the authors of the Mapping Pathways
report, published this week. This may mean that strategies are implemented in
very different ways – or not at all – in different parts of the world.
As part of a wider project, the researchers interviewed 41
stakeholders (9 in India, 13 in South Africa and 19 in the US) and conducted
two further focus groups in the US. Stakeholders had influence on HIV/AIDS
prevention policy in their country, through their role in clinical care, policy, research or advocacy. Interviews explored participants’ perceptions of
antiretroviral-based prevention strategies – testing, linkage to care and
treatment; pre-exposure prophylaxis (PrEP) and microbicides.
Questions of costs and resources were often central to
participants’ perceptions of the relevance of these strategies. Because many
people with HIV cannot currently get the drugs they need, it was hard for
stakeholders to justify delivering ARVs to HIV-negative people, even those at
high risk. Many did not accept that cheaper prevention options, such as condoms,
would not be sufficient.
“We already have a shortage of resources… And now we’re
talking about a massive roll-out in negatives? [I’ve been] one of the people
who was centrally involved in arguing the case for the affordability of ARVs in
South Africa in the 2000s, but even [I] think there just aren’t the resources –
This applied in all three countries, and in relation to each
Many were concerned about diverting resources away from existing
behavioural prevention approaches, as explained by this American respondent.
“This is ridiculous. Only 2-3% of the AIDS portfolio is
spent on prevention. Prevention money continues to go down. Switching funds [to
treatment as prevention] would result in total elimination of prevention funds.”
Especially in South Africa, the concern was not just about
financial resources, but the logistical capacity, human resources and political
backing that a health system would require to deliver these interventions.
While Indian stakeholders were generally the most sceptical
about the relevance of ARV-based strategies, they had some interest in 'treatment as prevention' as it was perceived to enable better access to
HIV treatment (that is needed anyway) for individuals with HIV.
Across all countries, there was generally more support
for this strategy than the other two.
Stakeholders from the United States were consistently the most
positive about all three ARV-based prevention strategies and least worried
about the nature of the science. They had questions about available resources,
but less concern about applicability and generalisability of the findings from
clinical trials. Whereas most American stakeholders supported changes in
treatment guidelines following the HPTN 052 trial, Indian and South African respondents
The greatest scepticism and uncertainty was expressed in
relation to PrEP. Respondents who felt it had applicability saw it as a tool
for high-risk groups, but there were disagreements about which populations
should be included, particularly in the light of disappointing results with
young African women. And there were concerns about how clinicians could
identify and reach the individuals at greatest risk.
“I am sceptical about how to use the PrEP results. I
think the guidelines could be modified to include the examples above (abused
women, sex workers, couples wanting to conceive, MSM who self- identify as high
risk) – but how do you put that in the guidelines – at the discretion of the
“In an Indian culture that still struggles to accept condoms, it would be difficult to get the general population to accept PrEP. While risk categories based on global norms are feasible to define and accept, it will be hard for an individual to accept that he or she is ‘high risk’ and should take this treatment.”
While participants were generally interested in vaginal
microbicides because of their potential to empower women, the mixed results of
the CAPRISA 004 trial raised a number of question about adherence and the very
high rate of new infections seen in the study. Respondents from South Africa (where
CAPRISA 004 was conducted) also raised questions about how microbicides should
be described and presented.
“The only way there will be more of a chance of them ever
being taken up by communities is if they are marketed as a sex toy or
lubricant. If you call them microbicides, you’ll sell 3 in 20 years... They now
need to be handed over to a marketing company to consider how to advertise them
as a sex toy. But [I] wonder how this could ever be done in practice. Grumpy
old nurses are funny about condoms so [they] would struggle with marketing a
product as sex enhancing.”
In relation to all methods, Indian stakeholders spoke of
mitigating local circumstances or politics as major obstacles to adoption. They
wanted to ground knowledge in their own setting and were often unwilling to
accept outside views or study results at face value.
The available data on the
prevention interventions come from randomised control trials (RCTs), which focus on
efficacy rather than effectiveness. RCTs provide evidence that is robust, but
rather narrow, the authors say.
Efficacy refers to whether the strategy has a beneficial
effect in a clinical trial setting, which typically has extra resources and
recruits a slightly atypical group of individuals to take part. Effectiveness
refers to evidence about whether the strategy works in day-to-day medical
practice. Here, variables such as individuals’ risk behaviour, adherence,
resources and health systems can effect whether the strategy works or not in
“Context matters,” say the authors. Future studies “need to
explore how the strategy would be implemented in a local context and what
social arrangements are needed to support it,” they say. The research found
that without such data, many stakeholders (especially in India and South
Africa) would be unwilling to recommend any implementation of treatment as
prevention, PrEP or microbicides.