Module 1 Basic definitions wwwicadcisdcom Objectives This workshop will Increase the capacity of media representatives to report on NPT trials with accuracy and sensitivity Build skills amongst communitybased organizations to critically analyze media discourse about HIV prevention tri ID: 208679
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New Prevention Technologies WorkshopModule 1: Basic definitions
www.icad-cisd.comSlide2
Objectives This workshop will:Increase the capacity of media representatives to report on NPT trials with accuracy and sensitivityBuild skills amongst community-based organizations to critically analyze media discourse about HIV prevention trialsIncrease the capacity of community representatives to understand and communicate NPT trial results effectivelySlide3
Warm-Up ExercisePlease read the articles that have been provided to you. They all report on the same trial results. Discuss Questions:
What is the tone of each article? (Optimistic? Pessimistic?)
What conclusion do you come to after reading each article?What information do you feel is missing? Slide4
Imagine a full spectrum of interventionsRights-focused behaviour change
Voluntary counselling &
testing
Sexually transmitted
infection screening
and treatment
Male medical circumcision
Preventative vaccines
Pre-exposure prophylaxis
(PrEP)
Male & Female condoms and lubricant
Treatment to prevent vertical transmission (PMTCT)Clean injecting equipmentPost-exposure prophylaxis (PEP)Vaginal & rectal microbicidesCervical barriers
Antiretroviral treatment
Treatment for opportunistic infections
Basic care/nutrition
Prevention for positives
Education and rights-focused
behaviour
change
Therapeutic vaccines
Functional curesSlide5
Which NPTs?Vaccines?
PrEP?
Microbicides?
Medical male circumcision?
Female condoms?
Treatment-as-prevention?Slide6
Medical male circumcisionSlide7
Medical male circumcision3 studies conducted: South Africa, Uganda, Kenya
Trials showed: circumcised men about 60% less likely to acquire HIV through unprotected vaginal intercourse
WHO published recommendation based on study resultsSlide8
Medical male circumcision60% risk reduction for HIV-negative circumcised men during unprotected vaginal intercourse with HIV+ womanTrials did not show reduction in transmission risk from circumcised HIV+ man to HIV-negative womanIn fact, one trial showed opposite trend: increased risk for wives of circumcised HIV+ husband; probably due to resuming sex too soon after circumcisionTrials did not provide information on effect of circumcision on HIV transmission during anal sex
—for either women or menSlide9
Challenges with Male CircumcisionPublic messages must be communicated very clearly: reduces but does not eliminate men’s HIV riskNeed to educate about the difference between FGC and male circumcision“Potential harmful outcomes”: condom substitution, surgical complications, inadequate healing timeReligious and cultural meanings of circumcision
Ethics of promoting circumcision for infant boysSlide10
Female condomsSlide11
Female Condomsa thin pouch that a woman can insert in her vagina before sex to prevent pregnancy and sexually transmitted infections (STIs), including HIVFC1: Polyurethane; FC2: nitrile rubber (less noisy, cheaper than FC1)the only proven, female-initiated method of HIV prevention currently on the market
can be used vaginally or anallysame efficacy as male condoms for STI prevention and contraception
Or “the internal condom”Slide12
Challenges with Female CondomsAlmost all (99.6%) condoms distributed globally are male condoms. Only a tiny fraction of women worldwide have access to female condoms. Why?
High price: US$0.60 vs. US$0.04 for male condom
Perceived and real acceptability issues: cumbersome, hard to use, partners do not like them, taboos around female sexuality
Not enough donor and policy-maker support
: low interest among some major donors and governments
Discomfort among “gatekeepers”:
health care providers and HIV and AIDS
programme
implementersSlide13
ARV-Based prevention methodsSlide14
ARV-based prevention options
PrEP
Treatment of HIV+
partner
Vaginal microbicides (rings)
Vaginal microbicides
(gels) and rectal microbicides
Preventing vertical transmission (PMTCT+)
PEPSlide15
HIV prevention
Not ARV-based ARV based
Male & female condoms
Circumcision
Clean injecting equipment
Vaccines
VCT
PEP
PrEP
Treatment for HIV+
partner
Vaginal and rectal microbicidesPreventingverticaltransmissionSlide16
PEPPreventing vertical transmission
(PMTCT)
Treat HIV+ partners
PrEP
Microbicides
Multiple ARVs
Nevirapine
; combination, if possible (AZT+3tc+
nevirapine
)
Multiple ARVs
Tenofovir and TruvadaTenofovir, TMC 120 (daviripine), UC781, MV-150Oral pills
Pills, dropper
Oral pills, injection
Oral pills
Vaginal and rectal gels with applicators, vaginal rings, film
Daily for 4 weeks
Varies from ongoing treatment to doses just before, during, after delivery
At least daily
At least daily, possible
dosing related to exposure
Before and possibly after sex, possibly daily dosing
Comparing ARV-based prevention methods
Drugs used
Delivery
formats
Frequency of useSlide17
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
Monkeys that get ARVs prior to exposure are less likely to be infected with “monkey forms” of
HIVSlide18
Treatment as preventionSlide19
Treatment as preventionCan it work at population level?Increased testing = more knowledge of status = less risk-taking
Increased testing = more HIV+ people on treatment = less virusLess risk-taking + less virus = less transmission?
HIV+ people taking ARVs regularly
Does it work at individual level?
Treatment = less virus = less
transmissionSlide20
Steps needed for“Treatment as prevention”Slide21
microbicidesVIDEOSlide22
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 monthSlide23
We need microbicides that: Are both contraceptive and not contraceptive
Help reduce the risk of getting other sexually transmitted infections
Are inexpensive and easily availableCan 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)Slide24
Why would HIV+ people want microbicides?To reduce the risk of co-infection with other HIV strains.
To reduce the risk of other sexually transmitted infections, and yeast and bladder infections
To allow conception whilst protecting partnerSlide25
2. Surfactants
3. Block binding
4. Stop replication
1. Boost vagina’s natural defences
5. Future possibility
*STDs:
sexually transmitted diseases
*Slide26
Comparing ARV-based and non-ARV-based microbicides
ARVNot ARV
Advantages
Disadvantages
More potent against HIV
May be long lasting
Not contraceptive
May be more toxic
May cause resistance
Unlikely to protect against other sexually transmitted infections
Could work against HIV and other sexually transmitted infections
Could be contraceptive
May be less potent against HIV
Must be used at time of sex Slide27
Pre-exposure prophylaxisSlide28
Pre-exposure prophylaxis (PrEP) 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
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.Slide29
What makes a drug a good candidate for PrEP?
Now being tested: tenofovir
(Viread)
Truvada
(
tenofovir+emtricitabine
combined)
Easy to use:
Only one pill required per day (maybe less)Safe: Few side effects in HIV-positive people
Powerful: Stays in the bloodstream a long time
Unique resistance profiles: If resistance develops, other treatment options still existSlide30
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 AsiansSlide31
Issues around ARV-Based prevention methodsSlide32
Drug resistanceMore 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 pointSlide33
Think of weeds in a gardenIf you use weed killer:
Some weeds dieOthers thrive, grow bigger, and take over
The weed killer accidentally helps resistant weeds – it takes away all their competition
To stop the big weeds:
Take
away the first weed
killer
Introduce other weed killers that stop all weeds – big and
small
Concept
for this slide:
Jeanne
Marrazzo
, MD
and
John
Mellors
, MD, MTNSlide34
Next steps for scienceGather more data on how PrEP works across populations
Address safety concerns through current trials and further research
Learn how to monitor widespread resistance
Study intermittent use: for example, taking it only when you expect to have sex.
Find out about impact on pregnancy and breast feeding
Test other ARVs to see if they might also work as
PrEPSlide35
Immune system, HIV and vaccinesVIDEOSlide36
VaccinesA vaccine is a substance that teaches the body to recognize and defend itself against bacteria and viruses that cause disease.
A vaccine causes a response from the immune system—the body's defense system—preparing it to fight, and also to remember how to fight, if exposed to a specific infection.
A vaccine is not a cure, but prevents infection or slows disease progression.Slide37
A vaccine primer200 years of vaccines
Common vaccinesTypes of immunity:
humoral (antibody) and cell-mediated
An ideal HIV vaccine
Preventative or therapeutic?Slide38Slide39
Immune responseSlide40
Challenges in HIV Vaccine ResearchDesigning the vaccine: need a different approach for HIV vaccinesAnimal models: have not yet accurately predicted how they will work in humansUnknown correlates of protection:
don’t know what immune responses will protect an individual from infectionHIV mutation: there are many different subtypes of HIV, may require matching vaccinesSlide41
…but on the bright side…Broadly neutralizing antibodies found
Precedent from other systems: Success against other viral infections
Precedent from animal studies: Long-term control of infection in vaccinated monkeys
Immune control of HIV-1: Infected individuals control infection
Vaccine trials: In progress
Slide42
Gender implicationsSlide43
Gender and HIVWhat do we mean by “gender”? Is it the same as “sex”?
What factors influence vulnerability to HIV?
What impact does gender have on HIV prevention?
For women?
For men?
For gay men?Slide44Slide45Slide46
What women need to protect themselves
Protection
Technology
Economic
opportunities
Social powerSlide47
Questions women have about ARV-based prevention
If I think my husband has HIV, will I be able to get PrEP?
If I use a microbicide,
how will I make my man use a condom?
Even if the doctor gives me pills, will I be able to keep them for myself?Slide48
More questions women have
Will it make me sick?
Will my husband let me go to the clinic?
People will notice if I have to go in for testing and to get my pills. What will they say about me?
Can I take PrEP when I am pregnant?
Will it hurt my baby?
What about breastfeeding?
How much
will it cost?
Where will I get it?