The State Of The Science: Combination Prevention Technologies Perry N. Halkitis, PhD, MSProfessor of Applied Psychology, Public Health, and Medicine Director, CHIBPS New York University Presentation for HealthHIV SYNChronicty Conference April 20, 2012
Biomedical Approaches to HIV Prevention• Anti-HIV Microbicides – advantage of being receptive-partner controlled – vaginally or rectally applied gels, foams, and creams – HIV-specific and nonspecific compounds• Male Circumcision – cost and infrastructure limitations especially in developing world – operational, religious, political, and logistic factors• Vaccines – Still under development• PEP – Long history of use in medical settings
Biomedical Approaches to HIV Prevention• Pre-exposure Prophylaxis (PrEP)• Treating/HIV Treatment (including after Targeting and Testing)
Treating• HPTN 052 trials (NIAID, 2011) – HIV+ individuals initiating ART decreased transmission rates to sexual partners by 96%• The Swiss Statement/Swiss Federal Commission for HIV/AIDS – “An HIV-infected person on antiretroviral therapy with completely suppressed viraemia (“effective ART”) is not sexually infectious, i.e. cannot transmit HIV through sexual contact.” – Contingencies • the person adheres to antiretroviral therapy, the effects of which must be evaluated regularly by the treating physician, and • the viral load has been suppressed (< 40 copies/ml) for at least six months, • there are no other sexually transmitted infections.
Treating• Uganda Couples Study (Quinn, 2000) – 415 heterosexual serodicsordant couples in Uganda – Viral load above 50,000 copies in the HIV-positive partner was most strongly associated with the risk of transmission: 23 infections per 100 person years – Viral load between 400 and 3499: 2.2 infections per 100 person years – Viral load < 1500: 0 infections
PrEP• CAPRISA 004 trials (Karim et al. 2010) – women receiving tenofovir gel were 39% less likely to contract HIV than those receiving placebo• Pre-exposure Prophylaxis Initiative (iPrEx) trials (Grant et al. 2010) – HIV-negative gay men given Truvada had 44% lower infection rates than men given placebo
PrEP• Partners PrEP Trial (Baeten, 2011 ) • HIV-negative partners in serodiscordant couples • HIV-negative partners taking tenofovir had 62% less risk for infection • those taking, tenofovir plus emtricitabine (Truvada) had 73% less chance of infection – Tenofovir: 68% in women 58% in men – Truvada : 62% in women, 83% in men
Biomedical Approaches to Prevention• Research supports the efficacy of some biomedical interventions!!!
Biomedical Interventions• Research also indicates less than optimal results for other biomedical interventions – FEM-PrEP study was halted in April 2011 • Failures related to adherence • Among those who were on Truvada and seroconverted • 26% had detectable levels of tenofovir in their blood in the last visit before they tested HIV positive
What is Wrong with Behavioral Interventions?• There is questionable effectiveness of behavioral interventions – Focus on reducing risk for infection – Focus on person-level factors such as motivation, efficacy, temptation etc. – Focus on rational decision making--social cognitive frames • Rational operators – Perhaps unsustainable
But is the solution to HIV prevention acomplete shift from the behavioral to thebiomedical without any consideration to psychological or social processes?
What Do the Biomedical Studies Teach Us?• Biomedical interventions despite their high level of effectiveness, involve a critical human component• Biomedical interventions only work when uptake and adherence are optimized• We cannot separate the person from the intervention
What is the Solution?• Combining the best of biomedical treatment (e.g., PrEP or initiating HIV treatment) with behavioral components• Biomedical interventions would likely yield even better outcomes if combined with appropriate behavioral and /or social interventions• “Don’t throw out the baby with the bath water!”
Why an Integrated Approach to HIV Prevention1. The success of biomedicalinterventions is dependent on behavioralfactors affecting medication adherenceand treatment uptake (i.e., treatmentacceptability and use) (Weiss et al. 2008)
2. Treatment adherence “sticking to theregimen”) plays central role in biomedicalinterventions including treatment for HIV (U.S., DHHS, 2011) PrEP (e.g., Grant et al. 2010) PEP (e.g., Chacko et al, 2012)
3. Adherence is influenced by a variety of bio-psycho-social factors that may both enhance and diminish this behavior – Patient based factors – Providers based factors – Treatment based factor – Contextual factors
4. Biomedical interventions withoutcombined behavioral approaches haveshown suboptimal medication adherenceand treatment uptake – only 27 %of drug users in need of the Hepatitis B vaccine completed the required three dose regimen (McGregor et al. 2003) – and only 28.2% of young women at a clinic who were offered the human papillomavirus vaccine accepted and of those who accepted only 55.7% completed all three required doses (Moore, et al. 2010)
5. Medication adherence and treatmentuptake of biomedical interventions can beaddressed by behavioral interventionsthat enhance knowledge and build skills
Application to HIV Prevention• Biological factors: the virus (e.g., PrEP and treatment) – emerging• Psychological factors: the person (behavioral intervention) – established• Social factors: the context (structural intervention) – only scratching the surface
The Social Factors• Science clearly shows that HIV disease isfueled by… –Poverty –Discrimination –Homophobia –Victimization –Gender bias •EXPLAIN THE PATTERNS OF INFECTION IN GAY AND BISEXUAL MEN AND AFRICAN AMERICANS
• The development of interventions and social policies to address these social ills are critical to HIV prevention – Behavioral interventions: INSUFFICIENT – PrEP/Biological interventions: INSUFFICIENT – Behavioral + Biological: ALSO LIKELY INSUFFICINET
A NEW GENERATION OF HIV PREVENTION BIOMEDICAL APPROACHES +BEHAVIORAL SUPPORT/PROGRAMS + SOCIAL POLICIES/STRUCTURAL INTERVENTIONS
• PREP OR TREATING to deter infection from the virus• BEHAVIORAL SUPPORT to (1) support uptake, adherence and maintenance (2) develop and understanding of PREP, and (3) to reinforce condom use and safer sex strategies• SOCIAL POLICY to combat social inequalities and decrease vulnerability to HIV infections
A 3-ProngedApproach• biological, psychological, social• just like we approach HIV treatment with combinations of drugs across classes• The most effective HIV prevention program and policy will marry all 3 components