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Introduction: HIV pre-exposure prophylaxis (PrEP) significantly reduces the risk of HIV acquisition. However, studies have demonstrated discordance between self-reported measures and biomedical benchmarks of PrEP adherence. We estimated the correlation between self-reported PrEP adherence and PrEP biomarkers and explored factors associated with adherence among men who have sex with men (MSM) in Nigeria., Methods: TRUST-PrEP, an open-label, prospective study; conducted in Abuja between April 2018 and May 2019. MSM ≥ 18 years with substantial HIV risk were enrolled. Participants reported PrEP adherence in the last month using a 4-point scale from "poor" to "perfect" and serum samples for PrEP biomarkers were collected at months 3 and 9. Serum tenofovir concentration was measured by liquid chromatography-tandem mass spectrometry and considered protective for adherence if ≥ 4.2 ng/ml. Spearman's rank correlation was used to estimate correlation between self-reported adherence and measured tenofovir levels. Generalized estimating equations with a logit link was used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for associations between self-reported adherence and laboratory-measured adherence., Results: A total of 219 MSM with median age 23 (interquartile range 20-27) years had at least one PrEP biomarker assay. Only 66/219 (30%) had at least one record of protective tenofovir concentration. Correlation between tenofovir and self-reported adherence at 3 and 9 months were 0.1 and 0.02 respectively. Furthermore, 17/219 (8%,) and 49/219 (22%) had serum tenofovir of 4.2-35.4 ng/mL and ≥ 35.5 ng/mL, corresponding to at least 4 and 7 days' PrEP use in a week, respectively. PrEP adherence was higher among participants introduced to PrEP in the clinics compared with communities (aOR: 8.35, 95%CI: [3.24, 21.5]) and those with same-sex practices family disclosure (aOR: 3.60 95% CI: [1.73, 7.51])., Conclusion: Self-reported PrEP adherence poorly correlated with biomarkers. Facilitating clinic-based PrEP introduction and disclosure of same-sex practices to family among MSM may improve PrEP adherence., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Adeyemi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: As pre-exposure prophylaxis (PrEP) becomes more widely used in heterosexual populations, an important consideration is its safety in infants who are breastfed by women taking PrEP. We investigated whether tenofovir and emtricitabine are excreted into breast milk and then absorbed by the breastfeeding infant in clinically significant concentrations when used as PrEP by lactating women., Methods and Findings: We conducted a prospective short-term, open-label study of daily oral emtricitabine-tenofovir disoproxil fumarate PrEP among 50 HIV-uninfected breastfeeding African mother-infant pairs between 1-24 wk postpartum (ClinicalTrials.gov Identifier: NCT02776748). The primary goal was to quantify the steady-state concentrations of tenofovir and emtricitabine in infant plasma ingested via breastfeeding. PrEP was administered to women through daily directly observed therapy (DOT) for ten consecutive days and then discontinued thereafter. Non-fasting peak and trough samples of maternal plasma and breast milk were obtained at drug concentration steady states on days 7 and 10, and a single infant plasma sample was obtained on day 7. Peak blood and breast milk samples were obtained 1-2 h after the maternal DOT PrEP dose, while maternal trough samples were obtained at the end of the PrEP dosing interval (i.e., 23 to 24 h) after maternal DOT PrEP dose. Tenofovir and emtricitabine concentrations were quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS) assays. Of the 50 mother-infant pairs enrolled, 48% were ≤12 wk and 52% were 13-24 wk postpartum, and median maternal age was 25 y (interquartile range [IQR] 22-28). During study follow-up, the median (IQR) daily reported frequency of infant breastfeeding was 15 times (12 to 18) overall, 16 (14 to 19) for the ≤12 weeks, and 14 (12 to 17) for the 13-24 wk infant age groups. Overall, median (IQR) time-averaged peak concentrations in breast milk were 3.2 ng/mL (2.3 to 4.7) for tenofovir and 212.5 ng/mL (140.0 to 405.0) for emtricitabine. Similarly, median (IQR) time-averaged trough concentrations in breast milk were 3.3 ng/mL (2.3 to 4.4) for tenofovir and 183.0 ng/mL (113.0 to 250.0) for emtricitabine, reflecting trough-to-peak breast milk concentration ratios of 1.0 for tenofovir and 0.8 for emtricitabine, respectively. In infant plasma, tenofovir was unquantifiable in 46/49 samples (94%), but emtricitabine was detectable in 47/49 (96%) (median [IQR] concentration: 13.2 ng/mL [9.3 to 16.7]). The estimated equivalent doses an infant would ingest daily from breastfeeding were 0.47 μg/kg (IQR 0.35 to 0.71) for tenofovir and 31.9 μg/kg (IQR 21.0 to 60.8) for emtricitabine, translating into a <0.01% and 0.5% relative dose when compared to the 6 mg/kg dose that is proposed for therapeutic treatment of infant HIV infection and for prevention of infant postnatal HIV infection; a dose that has not shown safety concerns. No serious adverse effects were recorded during study follow-up. The key study limitation was that only a single infant sample was collected to minimize venipunctures for the children. However, maternal daily DOT and specimen collection at drug concentration steady state provided an adequate approach to address the key research question. Importantly, there was minimal variation in breast milk concentrations of tenofovir and emtricitabine (respective median trough-to-peak concentration ratio ~1), demonstrating that infants were exposed to consistent drug dosing via breast milk., Conclusion: In this short-term study of daily directly observed oral PrEP in HIV-uninfected breastfeeding women, the estimated infant doses from breast milk and resultant infant plasma concentrations for tenofovir and emtricitabine were 12,500 and >200-fold lower than the respective proposed infant therapeutic doses, and tenofovir was not detected in 94% of infant plasma samples. These data suggest that PrEP can be safely used during breastfeeding with minimal infant drug exposure., Trial Registration: ClinicalTrials.gov, Identifier: NCT02776748., Competing Interests: I have read the journal's policy, and the authors of this manuscript have the following competing interests: FTC-TDF was donated by Gilead Sciences. CWH reports a prior contract from Gilead Sciences outside the submitted work and a patent pending, both managed by Johns Hopkins. MM has grant funding via the NIH. GJS has research grants from NIH (unrelated), CDC (unrelated), Thrasher Foundation (unrelated), Bill and Melinda Gates Foundation (sponsor), royalties from UpToDate (unrelated), and salary support from the University of Washington. All authors declare no other conflicts of interest.

Background: National Institute of Mental Health Project Accept (HIV Prevention Trials Network [HPTN] 043) is a large, Phase III, community-randomized, HIV prevention trial conducted in 48 matched communities in Africa and Thailand. The study intervention included enhanced community-based voluntary counseling and testing. The primary endpoint was HIV incidence, assessed in a single, cross-sectional, post-intervention survey of >50,000 participants., Methods: HIV rapid tests were performed in-country. HIV status was confirmed at a central laboratory in the United States. HIV incidence was estimated using a multi-assay algorithm (MAA) that included the BED capture immunoassay, an avidity assay, CD4 cell count, and HIV viral load., Results: Data from Thailand was not used in the endpoint analysis because HIV prevalence was low. Overall, 7,361 HIV infections were identified (4 acute, 3 early, and 7,354 established infections). Samples from established infections were analyzed using the MAA; 467 MAA positive samples were identified; 29 of those samples were excluded because they contained antiretroviral drugs. HIV prevalence was 16.5% (range at study sites: 5.93% to 30.8%). HIV incidence was 1.60% (range at study sites: 0.78% to 3.90%)., Conclusions: In this community-randomized trial, a MAA was used to estimate HIV incidence in a single, cross-sectional post-intervention survey. Results from this analysis were subsequently used to compare HIV incidence in the control and intervention communities., Trial Registration: ClinicalTrials.gov NCT00203749.