Table 1.
Efficacy data for HIV PrEP in women
Study | Year | Location | No of women enrolled | Regimen(s) tested* | Efficacy for women | Adherence |
---|---|---|---|---|---|---|
TDF24 | 2012 | Botswana | 557 | Daily oral TDF/FTC | 49% (95% CI −22% to 81%)† | Detectable plasma tenofovir levels in 80% of women who did not acquire HIV vs 50% of women who acquired HIV |
Partners PrEP3 | 2012 | Kenya, Uganda | 4,758 couples, 1,164 with women as HIV-uninfected partner assigned to use PrEP (598 assigned to use TDF, 566 assigned to use TDF/FTC) | Daily oral TDF or TDF/FTC | TDF: 71% (95% CI 37% to 87%) TDF/FTC: 66% (95% CI 28% to 84%) | Detectable plasma tenofovir levels in 83% of women who did not acquire HIV vs 31% of women who acquired HIV |
FEM-PrEP12 | 2012 | Kenya, South Africa | 2,120 | Daily oral TDF/FTC | 6% (95% CI −52% to 41%) | Detectable plasma levels tenofovir in <40% of women |
VOICE13 | 2015 | South Africa, Uganda, Zimbabwe | 5,029 | Daily oral TDF or TDF/FTC, or daily intravaginal 1% tenofovir gel | TDF: −49% (95% CI −129% to 3%) TDF/FTC: −4% (95% CI -50% to 27%) Tenofovir gel: 15% (95% CI −21% to 39%) | Detectable plasma levels in 30% of women assigned to oral TDF and 29% of women assigned to oral TDF/FTC. 41% of women assigned to tenofovir gel had no tenofovir detected in any vaginal samples |
CAPRISA-00477 | 2010 | South Africa | 889 | Pericoital intravaginal 1% tenofovir gel | 39% (95% CI 6% to 60%) | 54% efficacy when adherence >80%; 38% efficacy when adherence 50%–80%; 28% efficacy when adherence <50% |
FACTS-00178 | 2015 | South Africa | 2,029 | Pericoital intravaginal 1% tenofovir gel | 0% (95% CI -40% to 30%) | 13% of women with consistent use of gel (≥80% of sex acts). 22% of women with tenofovir detected in cervicovaginal samples at all quarterly visits; detectable levels of tenofovir associated with 52% efficacy |
ASPIRE79 | 2016 | Malawi, South Africa, Uganda, Zimbabwe | 2,629 | Monthly intravaginal ring (DPV) | 27% (95% CI 1% to 46%) (56% risk reduction among women >21 years) | Drug levels in 82% of plasma samples and 84% of returned rings consistent with use of intravaginal rings. Lowest levels of adherence and no efficacy demonstrated among women <21 years old |
The Ring Study80 | 2016 | South Africa, Uganda | 1,959 | Monthly intravaginal ring (DPV) | 31% (95% CI 1% to 51%) | Drug levels in 83% of plasma samples and 84% of returned rings consistent with use of intravaginal rings. 38% efficacy among women >21 years old; no efficacy among women ≤21 years old. 65% efficacy when ≤20 mg residual dapivirine in ring |
Bangkok Tenofovir Study6 | 2013 | Thailand | 489 | Daily oral TDF | 79% (95% CI 17% to 97%) | 66% of women with detectable plasma TDF |
Notes:
All studies represent placebo-controlled efficacy trials.
The small number of study endpoints among women participants limited the statistical power to detect significant effect sizes for women.
Abbreviations: TDF, tenofovir disoproxil fumarate; FTC, emtricitabine; DPV, dapivirine; PrEP, pre-exposure prophylaxis; CI, confidence interval.