HIV-1 Vaccine Development Clinical Trials and Public Health Benefits Chaiyos Kunanusont HIV/AIDS Adviser United Nations Population Fund

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1 The 2 nd Advanced Vaccinology course (NVCO) DDC, Radisson Bangkok June 2010 HIV-1 Vaccine Development Clinical Trials and Public Health Benefits Chaiyos Kunanusont HIV/AIDS Adviser United Nations Population Fund

2 What will be discussed here Before discussing public health benefits, what are public health risks? Public health benefits Prepare to use an HIV-1 vaccine the meeting in Korea 2000 Societal benefits Where should we put an HIV-1 vaccine in the current public health interventions?

3 Public Health Risks False expectations Individual level: Increased risky behaviours Authority level: Irrational investment in vaccine, re-allocating resources from other HIV prevention Guinea pig phenomenon Feeling betrayal among subjects and communities Barriers to subsequent vaccine development Different access due to economic status Expensive vaccines e.g. Hepatitis B, HPV

4 Public Health Benefits Reduce HIV transmission Reduce susceptibility less likely to be infected Reduce infectiousness less likely to transmit Delay disease progression Prolong disease free duration Reduce incidence rates of AIDS related illnesses Reduce AIDS related mortality (This can cause negative effects if infectiousness is not reduced)

5 From clinical trials to implementation Efficacy versus Effectiveness Clinical trial subjects are selected and are more disciplined than general populations (RV144 involves community people with low 47.5% or moderate risks 28.4%) Field factors (RV144 is a community based study) Co-administration with other vaccines Economic determinants Efficiency and Affordability Cost effectiveness and total impacts (direct, indirect) (RV144 does not provide these data)

6 Possible number of HIV prevented if RV144 were implemented in Thailand Group Pop size Reached Prevalence PLHIV No vacc No vacc VE 31.2% VE 31.2% reached 32% TX 4% TX 32% TX 4% TX Female SW 111,611 78, ,906 1, Male SW 5,922 4, IDU 15,000 76, ,400 12,288 1,536 3, MSM 680, , ,210 19,587 2,448 6, Male migrants 727, , ,094 2, Female migrants 546, , ,099 1, Conscript 50,000 50, ANC 800, , ,600 2, Youth - boys 4,834,968 3,867, ,868 1, Youth - girls 4,681,105 3,744, ,745 1, A few thousands will be prevented among ten millions immunized

7 The meeting in Korea 2000

8 Modeling the benefits 1. Health benefits i.e. saving medical expenditures as the results of infections and diseases prevented (incidence x medical expenditures per case) 2. Societal benefits i.e. saving losses of productive capacity among populations involved in vaccine programme

9 Health benefits of a new HIV vaccine Higher benefits in countries with higher medical expenditures (expensive care) Higher benefits in countries with higher incidence (new cases)

10 HIV/AIDS increases needs for health services in the aspects of quantity and price The more expensive health care is, the more benefit a vaccine will cause Source: Mead Over Impact of the HIV/AIDS Epidemic on the Health Sectors of Developing Countries

11 Estimated saving per case A new HIV vaccine is likely to benefit higher income countries due to medical benefits

12 HIV transmissibility 120% Thailand HIV Transmission Rates Incidence:Prevalence Ratio 100% 80% 60% Transmission rate in Thailand has decreased from 32 percent in early nineties to 4 percent recently Transmission rate 96% CI lower limit 95% CI upper limit 40% 20% 0% Year

13 HIV epidemic in Asia is also stabilized As HIV epidemic is more stabilized, health benefits of an HIV vaccine becomes limited

14 Societal benefits Similar to health benefits, societal benefits are a composite result of incidence (prevalence) of HIV and per individual productivity. Societal benefits are: Higher in high prevalence countries Higher in high production countries Higher where life expectancy is high

15 RV144 raises a critical question Should HIV-1 vaccine be applied among higher risk or lower risk populations or both? RV144 Efficacy is higher among populations with low and medium risk what is the estimated number of HIV prevented per index case by groups? Female SW 111,611 Male SW 5,922 IDU 15,000 MSM 680,106 Male migrants 727,531 Female migrants 546,497 Conscript 50,000 ANC 800,000 Youth - boys 4,834,968 Youth - girls 4,681,105 VE # prev Per index case High Risk 812, , Medium Risk 2,124, ,011, Low Risk 9,516, ,844,

16 Where to slot an HIV vaccine in Generally thinking administer a preventive HIV vaccine among populations with high risks RV144 reminds us to re-think about groups of populations. RV144 opens doors to more studies on immunology, regimen (frequency) and vaccine design (combination) RV144 demonstrates immediate benefits of community involvement