Table 1.
Scenario sets to evaluate the impact of pre-exposure prophylaxis (PrEP) use by adolescent sexual minority males using empirical adherence and retention parameters
| Scenario seta | Data source | Study arm | Adherence (% of PrEP users adhering at each level) |
Retention |
|---|---|---|---|---|
| 1 | EPIC: N = 121; MSM (ages 18–29); recruited through the CORE center, Chicago Il.; Primary outcomes: retention - attendance at 4, 12, 24, and 36 weeks; adherence - TFV-DP levels | Standard care | 57% – High (≥4 days; >719 fmol/punch plasma tenofovir) 14.3% – Moderate (2–3 days)b 14.3% – Low (<2 days)b 14.3% – None (BLQc)b |
57% at 36 weeks |
| Intervention | 72% – High (≥4 days; > 719 fmol/punch plasma tenofovir) 9.3% – Moderate (2–3 days)b 9.3% – Low (<2 days)b 9.3% – None (BLQc)b |
80% at 36 weeks | ||
| 2 | ATN113: N = 78; ASMM (ages 15–17); recruited across the ATN cities; Primary outcomes: retentions - attendance at 4, 8, 12, 24, and 36 weeks; adherence - TFV-DP levels | Standard care (last 36 weeks of ATN113) | 27.5% – High (≥4 days; >719 fmol/punch plasma tenofovir) 9.3% – Moderate (2–3 days) 26.3% – Low (<2 days) 36.9% – None (BLQc) |
50% at 48 weeks |
| Intervention (first 12 weeks of ATN113) | 55.8% – High (≥4 days; >719 fmol/punch plasma Tenofovir) 16.9% – Moderate (2–3 days) 22.5% – Low (<2 days) 4.8% – None (BLQc) |
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| 3 | EPIC and ATN113 | Standard care (entire ATN113 study period) | 41.6% – High (≥4 days; >719 fmol/punch plasma tenofovir) 13.1% – Moderate (2–3 days) 24.4% – Low (<2 days) 20.9% – None (BLQc) |
50% at 48 weeks |
| Intervention (relative change in EPIC applied to standard care) | 52.4% – High (≥4 days; >719 fmol/punch plasma tenofovir) 10.5% – Moderate (2–3 days) 20.0% – Low (<2 days) 17.1% – None (BLQc) |
70% at 48 weeks |
ASMM = adolescent sexual minority males; MSM = men who have sex with men.
a
Estimates of sexual mixing by age were derived from RADAR, a Chicago longitudinal cohort study of AMSM and young adult MSM.
b
EPIC only reported high adherence so the remaining fraction was distributed equally across the remaining categories.
c
BLQ = below the limit of quantitation.