Preparing for NPTs: Learning from the Past and Preparing for

the Future

Anthony Lombardo, PhD

July 27, 2011

Biomedical Approaches to HIV Prevention Vaccines Microbicides Pre-exposure Prophylaxis (PrEP) Post-exposure Prophylaxis (PEP)

Socio-Behavioural Issues of New Biomedical HIV Prevention Technologies Anthony Lombardo, January 2011, CATIE http://bit.ly/npt_sb

Partial Efficacy and the Uptake of New Biomedical HIV Prevention Technologies Anthony Lombardo, January 2011, CATIE http://bit.ly/npt_pe

Agenda Utilizing the technologies

Awareness Access Acceptability Adherence

Key socio-behavioural considerations Understanding risk Risk compensation Context of use Stigma

NPTs and the landscape of HIV prevention

Biomedical Prevention: Benefits Potential impact

Greater reach than behavioural interventions “Easier” to implement

Empowerment Women Men

But what are the “real life” challenges?

Importance of Social Science in Understanding NPTs and their Use Need to understand why people use

technologies – and why they don’t As with any other technology

Condoms, HAART

Need to understand how NPTs may change risk behaviour

Need to address these issues to support individuals’ use of the technologies

(Imrie et al., 2007; Kippax, 2008; Rosengarten et al., 2008)

Awareness of NPTs Awareness is key to uptake/use

Awareness of the technologies tends to vary by technology and population PEP: MSM, tends to be below 60% PEP: HIV+ women in London clinic, 80% had not

heard of PEP PrEP: MSM, approximately 20 – 25%

Awareness improved by campaigns

Acceptability of NPTs NPTs overall

Tend to be seen as acceptable…but a number of important considerations for acceptability: Efficacy of NPT at preventing HIV Side effects caused by NPT Cost of NPT

Microbicides Generally found acceptable by women, but concerns

about: Physical characteristics of the microbicide

Leakage, time of use, contraceptive properties Delivery method

Gels, rings, tablets Similar concerns about rectal microbicides, for both men and

women

Partial Efficacy Condoms &

microbicides

Partial Efficacy Condoms and Microbicides

Partial Efficacy Condoms and Microbicides

Acceptability of NPTs Gender/power relations play a role

Women’s use of microbicides in context of relationships

NPTs may be most acceptable to those most at risk for HIV infection NPT studies suggest people with higher sexual risk

more likely to use or be interested in using NPTs

Access to NPTs Access to NPTs impacted by individual and

structural factors Testing

Knowledge of HIV status Availability

Technologies themselves Someone who can prescribe them

Timely access e.g., clinic hours, clinician awareness, awareness of risk

Cost

Access to NPTs Disparities impact access to NPTs

Race, gender, socio-economic status Similar to disparities in access to HAART

Concurrent HIV risk behaviours may impact access e.g., drug use: stigma, social exclusion, housing

instability, health care system access (Krüsi et al., 2010)

Adherence to NPTs HAART adherence as guide Barriers and motivators at individual and

structural levels Fear of disclosure, depression, forgetting to take

medications, scheduling Stigma, social isolation, social networks

Side effects may be significant barrier HIV-negative people may not tolerate side effects

Adherence rates iPrEX trial: 2,499 HIV- MSM, 95% adherence CAPRISA 004 trial: 72% of sex acts (past 30 days)

covered by two doses of gel 40% of 889 women had less than 50% adherence

Key Socio-Behavioural Issues Understandings of Risk Risk Compensation Gender, Agency and Empowerment

Understandings of Risk How individuals think about their own “risk”

behaviour will impact use of technologies How do people decide if they have been at risk,

and therefore attempt to access an NPT? Understandings of risk influenced at numerous

levels Individual: decisions about the “safety” of a sexual

partner or a sexual act e.g., serosorting, strategic positioning

Community: setting the “criteria” for what makes a safe partner or a safe sexual act

Understandings of Risk People at risk for HIV may not realize that

they are, and may not access NPTs PEP

Sayer et al. (2008): MSM in Brighton, UK Men accessed PEP because of “unusual” or “rare” sexual

encounters Sex with a casual partner deemed ‘unsafe’, sex at a certain type

of venue, sex under the influence Schechter et al. (2004): Brazilian MSM

Top reasons for not using PEP: sex with steady partner and encounters considered ‘low risk’

Vaccine Low perceived risk for HIV associated with less uptake of

potential vaccine, among diverse populations Newman, et al., 2008; Ravert & Zimet, 2009; Rhodes &

Hergenrather, 2002; Rudy et al., 2005; Salazar et al., 2005

Understandings of Risk People may think they are at greater risk than

they actually are, leading to potential misuse of NPTs

The “worried well” Poynten et al. (2007): PEP requests in an Australian

cohort, 1998-2004 “relatively large number” of requests unnecessary because

HIV status of partner in the exposure known in only about 1/3 of cases

Pinkerton et al. (1998) Priority of PEP: partners of HIV+ people; receptive anal

intercourse; likely HIV+ partner; extenuating circumstances (violent sex, partner with other STDs)

“provision of PEP to individuals with low-risk of exposures would diminish overall cost-effectiveness of the program”

Ethics?

Risk Compensation People may increase their risk behaviour

because of the perceived protection from NPTs

Evidence is mixed But evidence is also “early”

Few NPTs in real-world application

Risk Compensation PrEP

Early evidence does not suggest an increase in risk behaviour iPrEX trial: no evidence of risk compensation Ghanaian PrEP trial showed no increase in risk behaviour

among women in the trial (Guest et al., 2008) Californian studies of MSM show under 10% of men would be

less safe with efficacious PrEP (AIDS Partnership California, 2009; Al-Tayyib et al., 2009)

Intentions to use PrEP not associated with HIV risk factors (Mimiaga et al, 2009)

Reports of ‘off-label’ use of ARVs for PEP/PrEP among MSM concerning (Mansergh et al., 2010) Compromising preventive and treatment aspects of ARVs Reliance on unproven technologies (Kellerman et al., 2006)

Risk Compensation Microbicides

Little direct evidence, but some suggestion of an inclination towards increased risk behaviour CAPRISA 004: no evidence of risk compensation Possible decreasing condom use with highly effective

microbicide (Thurman et al., 2009) Belief in protection of microbicide in clinical trial,

despite warnings about unknown efficacy (Mantell et al., 2006)

MSM use of dangerous/unproven rectal microbicides, such as nonoxynol-9 (Carballo-Diéguez et al., 2007; Mansergh et al., 2003)

Risk Compensation Vaccine

Trials show mixed evidence of risk compensation Early San Francisco trials showed increase in insertive

unprotected anal intercourse among participants (Chesney et al., 1997)

Other trials have found no increase in risk behaviours among participants (Bartholow et al., 2005; Lampinen et al., 2005; van Griensven et al., 2004)

Hypothetical vaccine studies suggest potential increase in risk behaviour Concerns that “others” would increase their risk

behaviour (Salazar et al., 2005; Webb et al., 1999) Individuals themselves suggesting they would increase

risk behaviour with efficacious HIV vaccine (Barrington et al., 2008; Crosby et al., 2006; Newman et al., 2009)

Risk Compensation Definitive statements about the impact of

NPTs on risk behaviour are not possible at present Available evidence has some shortcomings…

Must account for the role of risk reduction counseling in controlled NPT trials, which may not reflect “real life”

Studies of hypothetical use and/or risk compensation may not reflect “real life”

Promotion of NPTs must account for the possibility of risk compensation

NPTs will not provide protection against other STIs

Gender, Agency and Empowerment NPTs may offer choice for people – especially

women – who cannot control men’s use of condoms

Use of NPTs still impacted by gender inequalities and power relations Severy et al. (2005): microbicide acceptability in

context Individual-level

Beliefs about susceptibility to HIV impact use Relationship-level

New relationships vs. established ones; difficulties in bringing the subject up with partner; male partner views on microbicides

Socio-cultural level Gender/economic inequalities mean women’s dependence on

men; cultural norms about intravaginal practices

Gender, Agency and Empowerment Female-controlled prevention options may

have unintended consequences (Koo et al., 2005; Mantell et al., 2006; Woodsong, 2004) Repercussions if secretive use is discovered Discontinuation of condoms with women’s

microbicide use Emphasis on women’s responsibility for sexual

health, rather than shared responsibility NPTs can empower other groups with

difficulties in sexual negotiation

NPTs and Landscape of HIV Prevention Combination prevention

NPTs alone are not enough NPTs will likely not be 100% effective Behavioural strategies still necessary

Need to go “beyond the individual” NPTs used by individuals, but within a broader

context Use of NPTs needs to be understood from different

levels in which it will be used Individual, community, society

(Cohen et al., 2008; Padian et al., 2008; Vermund et al., 2009)

NPTs in ContextIndividual Relationship/

CommunitySociety

(Social, Political, Economic)

Awareness Social relations Social networks Mass media

Marketing strategies

Acceptability Others’ evaluations of microbicides

Agency to negotiate microbicide use

Side effects

Norms about NPTs in social networks

Meanings of sex and drug use

Power relations in sexual encounters

Gender inequality Social constructions of

masculinity Social constructions of

sexuality

Access Subjective risk calculations based on the type of partner or risk event

Barriers to HIV testing Barriers to timely

treatment Barriers to health care

access generally

Norms about “risk” and “safety” in social networks

Stigma about testing; HIV diagnosis; accessing NPTs

Availability of NPTs in local setting

Availability of NPTs NPT distribution

policies Public health care

coverage of NPTs Medical culture

surrounding NPTs Racial and gender

disparitiesAdherence Influence of

relationship partner Negotiation skills Cost of treatments Convenience of

treatments

Social support networks

Stigma

Availability of NPTs Public health care

coverage of NPTs

Implementing NPTs Connected and complementary services

Risk reduction counseling STI screening Hepatitis vaccinations Counseling Ongoing HIV-status monitoring

e.g., PrEP: side effects; HIV infection; increases in risk behaviour

(Clauson, 2009; Paxton et al., 2007; Pozniak, 2004)

Messaging and Marketing NPTs Emphasizing benefits and limitations of NPTs Address/discourage risk compensation Culturally- and gender-appropriate Communicating partial effectiveness

How to encourage uptake with technologies that are not 100% protective…and discourage risk compensation?

Utilize social theory to increase uptake of messages Use particular health behaviour change models

e.g., health belief model, stages of change, etc. But must still account for contextual issues(Access Working Group; Cassell et al., 2006; Eaton &

Kalichman, 2007; Global HIV Prevention Working Group, 2006; Nodin et al., 2008)

Messaging and Marketing NPTs Framing approaches

Downplaying focus on HIV prevention PEP as ‘morning after pill,’ PrEP as ‘birth control’ Microbicide as sexual enhancement rather than

HIV prevention Caution of unintended consequences

“Female-controlled” marketing may alienate men Marketing to high-risk groups may stigmatize the

NPT and reduce access Marketing a product to be used covertly?

(Access Working Group; Cassell et al., 2006; Eaton & Kalichman, 2007; Global HIV Prevention Working Group,

2006; Nodin et al., 2008)

Messaging and Marketing NPTs Whom to message?

Individual users Mass media

Social networks Partners, friends, families

Health care practitioners How are people talking about NPTs?

“Education” may not be the complete answer How people talk about NPTs may have a big

impact on how if and/or how they are used e.g., controversy over MMR (measles, mumps, rubella)

vaccinations Require grounding in local understandings

Need formative research

In Conclusion… NPTs must be understood within a broader

context Many issues involved in NPT access and use

depending on factors beyond the individual Messaging/marketing NPTs must account for

this broader context Risk compensation must be monitored,

especially in real-world application Behavioural approaches should not be

abandoned for biomedical interventions

HIV Prevention: The Bigger Picture

What does all of this mean for HIV prevention? Need to acknowledge shortcomings of three

different approaches Behavioural

Lack of coverage Biomedical

Science and uptake Structural

Difficult to implement Difficult to evaluate

Prevention needs to encompass all three levels

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