Developing the evidence base for biomedical prevention strategies
1. Developing the evidence
base for biomedical
prevention strategies
BACKGROUND METHODS
The world has made great progress in containing HIV since the epidemic peaked in the late 1990s. But there are still more than 2 Mapping Pathways used four multimodal, complementary methodologies to
million new infections a year. The current toolkit of prevention options is clearly not sufficient: a broader portfolio of approaches, or develop a comprehensive understanding of the evidence base, focusing on India,
pathways, to prevention is needed. Recent trial data shows great promise in four antiretroviral (ARV) prevention strategies: South Africa, and the United States. A (1) structured literature review and (2)
§ Testing, Linkage to Care Plus Treatment (TLC+): earlier treatment for HIV-positive people Delphi 'ExpertLens' on key faultlines provided a foundation for (3) semi-structured
§ Pre-exposure prophylaxis (PrEP): providing HIV-negative people with ARVs to prevent HIV interviews with 'grass tops' policy perspectives and (4) 'grass roots' opinions from
§ Vaginal and rectal microbicides: topical applications for HIV-negative people to prevent HIV an online community survey.
§ Post-exposure prophylaxis (PEP): providing ARVs to HIV-negative people with a potential recent exposure to HIV.
Such an adaptive approach to policy development, where “grasstops”
Though ARV-based prevention strategies show promise, they raise complex challenges, including access, cost, behavioral impacts, and stakeholders and experts and ”grassroots” communities are engaged in reflexive
drug resistance. The broader empirical evidence base for approval and implementation is still under development. and iterative exchanges of knowledge about the evidence needed for policy
development, is a methodological innovation in itself.
Mapping Pathways is a unique, community-led, study which is providing a multi-layered (scientific and stakeholder-based) synthesis of
the evidence base for ARV-based prevention strategies which tackle the HIV epidemic.
RESULTS
3. Forty-three stakeholders (India – 9; South Africa – 13; United States – 19, plus two small focus groups
in the US) were interviewed across the three countries in order to understand the decisionmaking
1.
The literature review retrieved 5,811 articles: 302 selected abstracts were needs of “grasstops” policy experts. The disciplines represented by the stakeholders varied
mapped and 100 articles analysed for efficacy, cost-effectiveness, indirect considerably and were not mutually exclusive, but could generally be distilled into one of five categories:
outcomes, and epidemiological impact data. Twenty-one clinical trials were clinical, advocacy, research/academician, political, or administrative.
reviewed, 31 modelling and cost studies (of which 9 examined cost-effectiveness and Even when looking at the exact same data, stakeholders in India, South Africa, and the United States often
14 looked at epidemiological modelling) and 30 cross-sectional, longitudinal, or came to very different conclusions about the implications of the findings and their relevance for HIV prevention
other intervention studies. We observe gaps in the empirical evidence base and and treatment policies in their countries.
argue it is still under development in critical areas (see Poster MOPE 591).
Do HPTN 052 trial findings support
changing treatment guidelines?
2. Thirty-two HIV/AIDS experts participated in a
RAND-developed, online Delphi-based discussion
called ExpertLens. Views were solicited on a
range of topics, including the comparative strengths
United States
(N=10)
South Africa
(N=13)
of the strategies. Experts generally thought TLC+ had
the strongest evidence, was most ready for
implementation, and most deserving of funds. India
(N=8)
Agreement varied on these comparative strengths,
though, and consensus only emerged for the TLC+ Mixed
Positive Skeptical
strategy in three areas: strength of the science, readiness
for implementation, and allocation of funds (see Poster
MOPE 591 for more information).
When looking across all strategies, stakeholders in each country had very different views about which
ExpertLens comparative assessment of would be most appropriate for their country. There is a wide divergence in views about whether
scientific data alone is necessary but not sufficient to bring about policy change. This range highlights
biomedical prevention strategies the importance of context in decisionmaking. Additional nuances were collected through qualitative
analysis of responses. Discussions and decisions are taking place, but expert stakeholders need more
1
information, particularly to
Percent of positive/mixed stakeholder review
Relative assessment
0.8 help contextualise the
scientific data. responses by biomedical prevention
0.6
0.4 strategy and country
0.2
100%
0
n
s
e
of tion
ty
sc of
nd
tio
India
nc
as t
en ss
ili
fe os
fu
gy h
ie
ib
ta
em ne
ca
C
te gt
lo
pl di
ra n
st Stre
Al
m ea
South Africa
riR
fo
United States
TLC+, Test & Treat, etc. Microbicides
PrEP PEP
50%
“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 “Well, from a programmatic perspective, there's a problem of
“high-risk” and should take this treatment.” (Indian stakeholder demand as we have low resources. We are having problems reaching
discussing PrEP) people who don't know they are positive now.. That is one of the
main concerns, there's no indication that as good idea as it is; that
implementation is feasible due to a lack of resources.” (US
“The only way there will be more of a chance of them ever being stakeholder discussing TLC+) 0%
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; if you PEP Topical PrEP TLC+ PrEP
call them applicators, you'll sell 2 in 20 years… they now need to be
handed over to a marketing company to consider how to advertise
4.
them as a sex toy” (South African stakeholder discussing Relative importance of biomedical prevention 1069 respondents participated
microbicides)
strategies from all survey respondents in the survey: 47.7% (USA),
32.3% (South African), and
100% 9.4% (India). A majority of the
respondents were male (53%), and
59% identified themselves as
work
Can ARVs and PEP
straight/heterosexual, 29.7% as gay,
ly
biological event, TLC+, Test & Treat, etc. 50%
and 6% as bisexual. Though country-
to pr
clinically treat? PrEP specific demographics of participants
not just Microbicides varied, the majority were
activists/advocates, worked for AIDS
0%
service organisations/NGOs, were
doctors, and/or were people living with
e gi t,
te en
n
HIV/AIDS. The majority of participants
at giv ,
n
po are
te en
te n
t
n
n
of e g d
no be ant
im gs t
or e n
an
io
io
at ve
or in bu
io
io
ts b n
m d b rta
at iv
in
lo ld nta
nt
nt
rt
nt
t
or
m r th nt,
op
ul po
felt that TLC+ was the most important
ou rta
ou p
he ta
ho im
sh im
o
RVs
ld
po
ot or
N
t s all
e
d all
p
im
er A of strategy, followed by microbicides.
im
the role
sh
bu at
an at
ry
eliv
is
How will fect policy?
ot
ot
Ve
It
N
e d tion?
N
w af
do even ‘publics’
How for pr nge
s
wed
a
cial
t so novat
Wh ect in
cha n?
io
ing
? negotia
e be rene
Will ther over patents?
tion CONCLUSIONS
aff ork e needed Findings underscore broad, often divergent views regarding the viability of ARV-based prevention, with TLC+
tw stems ar
isn’ What sy delivery? garnering the most optimism. However, Mapping Pathways findings provide empirical support for the argument
W hat for that an adaptive approach to policy development is required. This will enable understanding of the scientific data
behind the strategies (the physical technologies in red, on the left), but also knowing what 'social technologies'
(in grey) are needed to shape their implementation in culturally appropriate ways. An important series of
questions are raised about the systems in which these strategies might be introduced (in purple), and the
pathways needed to guide them.
Mapping Pathways has six partner organisations: AIDS Foundation of Chicago, AIDS United, Baird's CMC, Desmond Tutu HIV Foundation, Naz India and RAND. Mapping Pathways is funded by an initial grant from
Merck & Co., as well as an additional NIH ‘Be the Generation Bridge’ grant for dissemination and community engagement activities.
Blog: www.mappingpathways.blogspot.com
Facebook: www.facebook.com/MappingPathways
Twitter: @MappingPathways
DESMOND TUTU
HIV FOUNDATION
BAIRD’S CMC