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ARV-based
Prevention
Cindra Feuer and Marc-André LeBlanc
HRCF, 21 April 2010
33 million people now
live with HIV/AIDS
2.7 million new infections annually
Among newly infected people:
50% are women (higher in some areas)
95% live in developing countries
80–90% of all HIV+ people in southern
Africa do not know they have HIV
Percentage of at-risk people with
access to HIV prevention
<20% Sex workers with access to behaviour change
programmes
11% HIV+ pregnant women with access to PMTCT
Rose to 45%
recently
10–12% Adults in Africa accessing HIV testing
9% Men who have sex with men with access to appropriate
behaviour change programmes
9% Sexually active people with access to male condoms
8% Injection drug users with access to harm reduction
programmes
0
20
40
60
80
Global HIV Prevention Working Group 2008; WHO/UNAIDS/UNICEF 2007
100
HIV prevention
Not ARV-based





Male & female
condoms
Circumcision
Clean injecting
equipment
Vaccines
VCT


ARV-based
Vaginal and
rectal
microbicides
Preventing
vertical
transmission



PEP
PrEP
Treatment for
HIV+
partner
Why test ARVs to prevent HIV?

ARVs already are used to prevent vertical
transmission (or PMTCT).

PEP already is used to prevent infection after
medical accidents or rape.

Some evidence that lower viral load among HIV+
people on ARVs for treatment reduce risk of
transmission to HIV-negative partners

Monkeys that get ARVs prior to exposure are less
likely to be infected.
Strategies being researched

Oral Pre-Exposure Prophylaxis (PrEP): ARVs
taken regularly or before and after exposure
might reduce the risk of HIV infection

ARV-based microbicides: ARVs used in gels or
vaginal rings or other products that would be
inserted in the vagina or rectum to reduce the risk
of HIV infection
Pre-exposure prophylaxis (PrEP)
Experimental HIV prevention strategy that would use
ARVs to protect HIV-negative people from HIV
infection
Taking medicine to prevent rather than to treat a
disease or condition.
For example:
 Taking pills to prevent malaria when you travel.
 Using hormonal contraceptives (injections or pills) to
prevent pregnancy.
 Taking pills to avoid pneumonia, if you are at risk.
Safety concerns?




Safety is a critical issue for PrEP use
Look carefully at people with pre-existing
conditions: hepatitis B and C, kidney problems,
bone density
Pregnancy, post-menopause (osteoporosis),
adolescents (bone formation)
Look carefully at drug clearance in people with
low body weight, including women and Asians
PrEP: When will we know?
Where
Who
What
When
US (CDC)*
Men who have sex with
men
tenofovir
2010
Thailand (CDC)
Injection drug users
tenofovir
2010
Brazil, Ecuador,
Peru, US, Thailand,
South Africa (iPrEX)
Men who have sex with
men
Truvada
2010
Botswana (CDC)
Heterosexual men
and women
Truvada
2011
Uganda, Kenya
(Partners PrEP)
Serodiscordant couples
(men and women)
tenofovir, Truvada
2012
Kenya, Tanzania, South
Africa (FEMPrEP)
Women
Truvada
2012
South Africa, Uganda,
Zambia, Zimbabwe
(VOICE)
Women
tenofovir (pill &
gel), Truvada
2012
What is a microbicide?
A suppository or a gel
applied with an applicator
before sex
A vaginal ring that stays in
place for up to a month
We need microbicides that:






Are both contraceptive and not contraceptive.
Help reduce the risk of getting other sexually
transmitted infections.
Are inexpensive and easily available.
Can be used without a partner’s active
cooperation.
Can be used vaginally or rectally.
Can be used by HIV+ people (products not based
on ARVs).
Microbicides: When will we know?
Product
Trial sponsor
# participants
to be enrolled
Location(s)
First results
expected
Tenofovir gel
CAPRISA/CONRAD/
USAID/FHI
Tenofovir gel
MTN
980 women
South Africa
Early 2010
1,680 (in gel arms
of trial)
South Africa, Uganda,
Zambia, Zimbabwe
2012
Dapivirine
(TMC 120)
IPM
Tenofovir gel
MRC/UVRI
TBD
Various
TBD
TBD
Mozambique, South
Africa, Tanzania,
Uganda, Zambia
TBD
UC781
CONRAD/NIH/MTN
TBD
US
TBD
MIV-150
Population Council
TBD
US
TBD
If PrEP and ARV-based
microbicides work
1. Only take if you KNOW you are HIV negative.

Regular testing is necessary.
2. May be available by prescription only.

Access to a qualified health care provider is necessary.
3. Only the dosing used in trials is known to work.


PrEP: only daily dosing for now.
ARV-based microbicides: for now, applied daily or shortly
before sex.
Drug resistance

HIV makes thousands of copies of itself
daily.

Every time HIV copies itself, errors can
occur, like typing errors on a page.

These are mutations – changes that can
make the virus weaker or stronger.

If a mutation makes HIV able to resist an
ARV drug, it is called drug-resistant HIV.
Drug resistance





More likely if taking only one drug
(or one type of ARV)
Can still become HIV+ using
ARV-based prevention
Use by people who don’t know they
are HIV+ might lead to resistance?
Options for treatment may be more limited,
might pass on resistant virus
Unanswered questions at this point
Treatment as prevention
HIV+ people taking ARVs regularly


Does it work at individual level?
 Treatment = less virus = less transmission?
Can it work at population level?
 Increased testing = more knowledge of status = less
risk-taking
 Increased testing = more HIV+ people on treatment =
less virus
 Less risk-taking + less virus = less transmission?
Treatment as prevention
Test and treat (TNT) / Test, Link to Care Plus Treat
TLC-Plus: Theoretical model suggesting that
widespread HIV testing and treatment of all those
identified as HIV-positive would greatly reduce HIV
incidence and improve their health outcomes.
 HPTN 065, TLC-Plus: A Study to Evaluate the
Feasibility of an Enhanced Test, Link to Care Plus
Treat Approach for HIV Prevention in the United
States

Treatment as prevention
HPTN 052: Phase III, two-arm, multi-site, randomized
trial to determine the effectiveness of two
treatment strategies in preventing the sexual
transmission of HIV in HIV-serodiscordant couples.

CROI 2010. ART and Risk of Heterosexual HIV-1
Transmission in HIV-1 Serodiscordant African
Couples: A Multinational Prospective Study.
Advocates are calling for:





Better access to existing proven prevention
options.
Research into new prevention options, both ARV
based and not based on ARVs.
Research into drug resistance, alternate dosing,
pregnancy and breastfeeding, and a greater
variety of drugs.
Attention to access hurdles: more uptake of HIV
testing, access to prescribers.
Increased community engagement.
Questions?
What you can do:

Become better informed.
 Check

Tell your colleagues.
 Send

out the resources on the next slide.
them a link or a fact sheet.
Host a discussion forum.
 Use
this presentation at work or in your
community.

Join advocacy efforts.
 Contact
region.
other HIV prevention advocates in your
Stay informed
Join the Advocates’ Network: For regular HIV
prevention research updates join the AN at
www.avac.org/advocatesnetwork
Visit us at www.avac.org
For more information…
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PEP: http://tinyurl.com/hivpep
PMTCT: http://tinyurl.com/pmtct
PrEP: www.prepwatch.org
Microbicides
 www.global-campaign.org
 www.rectalmicrobicides.org
 www.ipm-microbicides.org
 www.microbicide.org (Alliance for Microbicide Development)

Treatment of HIV+ partner
 www.hptn.org
(look under HPTN052)
Why condoms are not enough