VIDI SYMPOSIUM

Criteria Influencing Potential Impact of HIV Prevention Interventions

January 14, 2008

Thomas Fleming, PhDUniversity of Washington

Fred Hutchinson Cancer Center

1. Percent of HIV transmission risk being addressed

~ Size of the risk group: fraction of the incidence ~ Attributable risk of transmission pathway addressed ~ Potential for reduction in secondary transmission

2. Intervention: Plausible Reduction in Relative Risk

~ Strength of “proof of concept” data ~ Likelihood for effect on secondary transmission

3. Feasible level of coverage of the target population ~ Affordability, Acceptability, Practicality

Criteria Influencing Potential Impact of HIV Prevention Interventions

~ 27% : Black/Hispanic MSM ~ 16% : Black/Hispanic Non-MSM

→ 7% heterosexual ; 9% IDU ~ 24% : White MSM ~ 3% : White Non-MSM Men

→ 1% heterosexual ; 2% IDU

~ 19% : Black/Hispanic Women (Heterosexual) ~ 5% : Black/Hispanic Women (Non-Heterosex)

→ IDU ~ 4% : White Women (Heterosexual) ~ 2% : White Women (Non-Heterosexual)

Size of the Risk Groups Fraction of the US Incidence

1. Percent of HIV transmission risk being addressed

~ Size of the risk group: fraction of the incidence ~ Attributable risk of transmission pathway addressed ~ Potential for reduction in secondary transmission

2. Intervention: Plausible Reduction in Relative Risk

~ Strength of “proof of concept” data ~ Likelihood for effect on secondary transmission

3. Feasible level of coverage of the target population ~ Affordability, Acceptability, Practicality

Criteria Influencing Potential Impact of HIV Prevention Interventions

Hypothetical Example ↓ in Substance Use in MSM

1. % of Tx risk addressed 11.25K (25% US incidence)

~ Size of risk group ~ 22.5K MSM ~ Attributable risk ~ 50% of MSM Tx ~ ↓ in secondary tx ( + )

2. Plausible ↓ in RR 4.5K (10% US incidence)

~ Established POC? ~ Expect 40% ↓ in risk ~ ↓ in secondary tx ( ─ )

3. Feasible coverage 2.25K (5% US Incidence) ~ Practical, Affordable? ~ Expect 50% coverage

Criteria Influencing Potential Impact of HIV Prevention Interventions

1. Percent of HIV transmission risk being addressed

~ Size of the risk group: fraction of the incidence ~ Attributable risk of transmission pathway addressed ~ Potential for reduction in secondary transmission

2. Intervention: Plausible Reduction in Relative Risk

~ Strength of “proof of concept” data ~ Likelihood for effect on secondary transmission

3. Feasible level of coverage of the target population ~ Affordability, Acceptability, Practicality

Criteria Influencing Potential Impact of HIV Prevention Interventions

Hypothetical Example ↓ in Substance Use in MSM

1. % of Tx risk addressed 11.25K (25% US incidence)

~ Size of risk group ~ 22.5K MSM ~ Attributable risk ~ 50% of MSM Tx ~ ↓ in secondary tx ( + )

2. Plausible ↓ in RR 4.5K (10% US incidence)

~ Established POC? ~ Expect 40% ↓ in risk ~ ↓ in secondary tx ( ─ )

3. Feasible coverage 2.25K (5% US Incidence) ~ Practical, Affordable? ~ Expect 50% coverage

Criteria Influencing Potential Impact of HIV Prevention Interventions

1. Percent of HIV transmission risk being addressed

~ Size of the risk group: fraction of the incidence ~ Attributable risk of transmission pathway addressed ~ Potential for reduction in secondary transmission

2. Intervention: Plausible Reduction in Relative Risk

~ Strength of “proof of concept” data ~ Likelihood for effect on secondary transmission

3. Feasible level of coverage of the target population ~ Affordability, Acceptability, Practicality

Criteria Influencing Potential Impact of HIV Prevention Interventions

Hypothetical Example ↓ in Substance Use in MSM

1. % of Tx risk addressed 11.25K (25% US incidence)

~ Size of risk group ~ 22.5K MSM ~ Attributable risk ~ 50% of MSM Tx ~ ↓ in secondary tx ( + )

2. Plausible ↓ in RR 4.5K (10% US incidence)

~ Established POC? ~ Expect 40% ↓ in risk ~ ↓ in secondary tx ( ─ )

3. Feasible coverage 2.25K (5% US Incidence) ~ Practical, Affordable? ~ Expect 50% coverage

Criteria Influencing Potential Impact of HIV Prevention Interventions

1. Percent of HIV transmission risk being addressed

~ Size of the risk group: fraction of the incidence ~ Attributable risk of transmission pathway addressed ~ Potential for reduction in secondary transmission

2. Intervention: Plausible Reduction in Relative Risk

~ Strength of “proof of concept” data ~ Likelihood for effect on secondary transmission

3. Feasible level of coverage of the target population ~ Affordability, Acceptability, Practicality

Criteria Influencing Potential Impact of HIV Prevention Interventions

Hypothetical Example ↓ in Substance Use in MSM

1. % of Tx risk addressed 11.25K (25% US incidence)

~ Size of risk group ~ 22.5K MSM ~ Attributable risk ~ 50% of MSM Tx ~ ↓ in secondary tx ( + )

2. Plausible ↓ in RR 4.5K (10% US incidence)

~ Established POC? ~ Expect 40% ↓ in risk ~ ↓ in secondary tx ( ─ )

3. Feasible coverage 2.25K (5% US Incidence) ~ Practical, Affordable? ~ Expect 50% coverage

Criteria Influencing Potential Impact of HIV Prevention Interventions

Illustrations Vaccine MCT ART 012, 046 052, 060 , Voice

1. % of Tx risk addressed

~ Size of risk group ++ + + ~ Attributable risk ++ ++ ++ ~ ↓ in secondary tx (+/─) ( ─ ) (+/─)

2. Efficacy of intervention

~ Established POC? ? ++ ? ~ ↓ in secondary tx ( ? ) ( ─ ) ( ? )

3. Feasible coverage ~ Practical, Affordable? + +/─ +

Criteria Influencing Potential Impact of HIV Prevention Interventions

~ 27% : Black/Hispanic MSM ~ 16% : Black/Hispanic Non-MSM

→ 7% heterosexual ; 9% IDU ~ 24% : White MSM ~ 3% : White Non-MSM Men

→ 1% heterosexual ; 2% IDU

~ 19% : Black/Hispanic Women: Heterosexual ~ 5% : Black/Hispanic Women: IDU

~ 4% : White Women: Heterosexual ~ 2% : White Women: IDU

Size of the Risk Groups Fraction of the US Incidence

1. Percent of HIV transmission risk being addressed

~ Size of the risk group: fraction of the incidence ~ Attributable risk of transmission pathway addressed ~ Potential for reduction in secondary transmission

2. Intervention: Plausible Reduction in Relative Risk

~ Strength of “proof of concept” data ~ Likelihood for effect on secondary transmission

3. Feasible level of coverage of the target population ~ Affordability, Acceptability, Practicality

Criteria Influencing Potential Impact of HIV Prevention Interventions

VIDI SYMPOSIUM

The Way Forward for

HIV Prevention:

Combination Strategies (HAARP)

Domestic & International

Vaccines Microbicides

ART MCT

STD IDU

Behavioral