The Effect of Disclosure of PrEP Use on Adherence Among African Young Women in an Open-Label PrEP Study: Findings from HPTN 082

To develop effective PrEP adherence interventions, it is important to understand the interplay between disclosure of pre-exposure prophalxis (PrEP) use, social support, and PrEP adherence. We leveraged the HPTN 082 study conducted among 451 adolescent girls and young women (AGYW) (ages 16 to 25 years, 2016 to 2019) in South Africa and Zimbabwe. Among the 349 who had month three disclosure and PrEP adherence data, 60% (n = 206) felt supported by adults, and 89% (n = 309) disclosed PrEP use to at least one person. PrEP disclosure was not associated with increased adherence, measured by intracellular tenofovir-diphosphate concentrations in dried blood spots. Women who reported having supportive adults, and disclosed to their parents, had higher adherence at 6 months with an increase of 177 fmol/punch (95% CI 12 to 343, t = 2.11, p = 0.04). PrEP interventions that help AGYW identify supportive relationships and effectively communicate the benefits of PrEP may improve PrEP adherence.Clinicaltrials.gov ID number: NCT02732730.

Adaptive Time-Location Sampling for COMPASS: A SARS-CoV-2 Prevalence Study in Fifteen Diverse Communities in the United States

BACKGROUND

COVID-19 has placed a disproportionate burden on underserved racial and ethnic groups, community members working in essential industries, those living in areas of high population density, and those reliant on in-person services such as transportation. The goal of this study was to estimate the cross-sectional prevalence of SARS-CoV-2 (active SARS-CoV-2 or prior SARS-CoV-2 infection) in children and adults attending public venues in 15 sociodemographically diverse communities in the United States and to develop a statistical design that could be rigorously implemented amidst unpredictable stay-at-home COVID-19 guidelines.

METHODS

We used time-location sampling with complex sampling involving stratification, clustering of units, and unequal probabilities of selection to recruit individuals from selected communities. We safely conducted informed consent, specimen collection, and face-to-face interviews outside of public venues immediately following recruitment.

RESULTS

We developed an innovative sampling design that adapted to constraints such as closure of venues, changing infection hotspots, and uncertain policies. We updated both the sampling frame and the selection probabilities over time using information acquired from prior weeks. We created site-specific survey weights that adjusted sampling probabilities for nonresponse and calibrated to county-level margins on age and sex at birth.

CONCLUSIONS

Although the study itself was specific to COVID-19, the strategies presented in this article could serve as a case study that can be adapted for performing population-level inferences in similar settings and could help inform rapid and effective responses to future global public health challenges.

Doxycycline post-exposure prophylaxis for sexually transmitted infections impacts the gut antimicrobial resistome

Doxycycline post-exposure prophylaxis (doxy-PEP) reduces bacterial sexually transmitted infections (STIs) among men who have sex with men and transgender women. While poised for widespread clinical implementation, the impact of doxy-PEP on antimicrobial resistance remains a primary concern as its effects on the gut microbiome and resistome, or the antimicrobial resistance genes (ARGs) present in the gut microbiome, are unknown. To investigate these effects, we studied participants from a randomized clinical trial who either received doxy-PEP as a one-time doxycycline 200 mg taken after condomless sex (DP arm, n = 100) or standard of care treatment (SOC arm, n = 50). From self-collected rectal swabs at enrollment (day-0) and after 6 months (month-6), we performed metagenomic DNA sequencing (DNA-seq) or metatranscriptomic RNA sequencing (RNA-seq). DNA-seq data was analyzable from 127 samples derived from 89 participants, and RNA-seq data from 86 samples derived from 70 participants. We compared the bacterial microbiome and resistome between the two study arms and over time. Tetracycline ARGs were detected in all day-0 DNA-seq samples and 85% of day-0 RNA-seq samples. The proportional mass of tetracycline ARGs in the resistome increased between day-0 and month-6 in DP participants from 46-51% in the metagenome (p = 0.02) and 4-15% in the metatranscriptome (p < 0.01), but no changes in other ARG classes were observed. Exposure to a higher number of doxycycline doses correlated with proportional enrichment of tetracycline ARGs in the metagenome (Spearman's ρ = 0.23, p < 0.01) and metatranscriptome (Spearman's ρ = 0.55, p < 0.01). Bacterial microbiome alpha diversity, beta diversity, and total bacterial mass did not differ between day-0 and month-6 samples from DP participants when assessed by either DNA-seq or RNA-seq. In an abundance-based correlation analysis, we observed an increase over time in the strength of the correlation between tetracycline ARGs and specific bacterial taxa, including some common human pathogens. In sum, doxy-PEP use over a 6-month period was associated with an increase in the proportion of tetracycline ARGs comprising the gut resistome, and an increase in the expression of tetracycline ARGs. Notably, doxy-PEP did not significantly alter alpha diversity or taxonomic composition of the gut microbiome, and did not demonstrate significant increases in non-tetracycline ARG classes. Further studies and population level surveillance are needed to understand the implications of these findings as doxy-PEP is implemented as a public health strategy.

Estimating the Effect of PrEP in Black Men Who Have Sex with Men: A Framework to Utilize Data from Multiple Non-Randomized Studies to Estimate Causal Effects

Black men who have sex with men (MSM) are disproportionately burdened by the HIV epidemic in the US. The effectiveness of pre-exposure prophylaxis (PrEP) in preventing HIV infection has been demonstrated through randomized placebo-controlled clinical trials in several populations. Importantly, no such trial has been conducted exclusively among Black MSM in the US, and it would be unethical and infeasible to do so now. To estimate the causal effects of PrEP access, initiation, and adherence on HIV risk, we utilized causal inference methods to combine data from two non-randomized studies that exclusively enrolled Black MSM. The estimated relative risks of HIV were: (i) 0.52 (95% confidence interval: 0.21, 1.22) for individuals with versus without PrEP access, (ii) 0.48 (0.12, 0.89) for individuals who initiated PrEP but were not adherent versus those who did not initiate, and (iii) 0.23 (0.02, 0.80) for individuals who were adherent to PrEP versus those who did not initiate. Beyond addressing the knowledge gap around the effect of PrEP in Black MSM in the US, which may have ramifications for public health, we have provided a framework to combine data from multiple non-randomized studies to estimate causal effects, which has broad utility.

Estimating counterfactual placebo HIV incidence in HIV prevention trials without placebo arms based on markers of HIV exposure

INTRODUCTION

Developing alternative approaches to evaluating absolute efficacy of new HIV prevention interventions is a priority, as active-controlled designs, whereby individuals without HIV are randomized to the experimental intervention or an active control known to be effective, are increasing. With this design, however, the efficacy of the experimental intervention to prevent HIV acquisition relative to placebo cannot be evaluated directly.

METHODS

One proposed approach to estimate absolute prevention efficacy is to use an HIV exposure marker, such as incident rectal gonorrhea, to infer counterfactual placebo HIV incidence. We formalize a statistical framework for this approach, specify working regression and likelihood-based estimation approaches, lay out three assumptions under which valid inference can be achieved, evaluate finite-sample performance, and illustrate the approach using a recent active-controlled HIV prevention trial.

RESULTS

We find that in finite samples and under correctly specified assumptions accurate and precise estimates of counterfactual placebo incidence and prevention efficacy are produced. Based on data from the DISCOVER trial in men and transgender women who have sex with men, and assuming correctly specified assumptions, the estimated prevention efficacy for tenofovir alafenamide plus emtricitabine is 98.1% (95% confidence interval: 96.4%-99.4%) using the working model approach and 98.1% (95% confidence interval: 96.4%-99.7%) using the likelihood-based approach.

CONCLUSION

Careful assessment of the underlying assumptions, study of their violation, evaluation of the approach in trials with placebo arms, and advancement of improved exposure markers are needed before the HIV exposure marker approach can be relied upon in practice.

Measuring HIV Acquisitions Among Partners of Key Populations: Estimates From HIV Transmission Dynamic Models

BACKGROUND

Key populations (KPs), including female sex workers (FSWs), gay men and other men who have sex with men (MSM), people who inject drugs (PWID), and transgender women (TGW) experience disproportionate risks of HIV acquisition. The UNAIDS Global AIDS 2022 Update reported that one-quarter of all new HIV infections occurred among their non-KP sexual partners. However, this fraction relied on heuristics regarding the ratio of new infections that KPs transmitted to their non-KP partners to the new infections acquired among KPs (herein referred to as "infection ratios"). We recalculated these ratios using dynamic transmission models.

SETTING

One hundred seventy-eight settings (106 countries).

METHODS

Infection ratios for FSW, MSM, PWID, TGW, and clients of FSW were estimated from 12 models for 2020.

RESULTS

Median model estimates of infection ratios were 0.7 (interquartile range: 0.5-1.0; n = 172 estimates) and 1.2 (0.8-1.8; n = 127) for acquisitions from FSW clients and transmissions from FSW to all their non-KP partners, respectively, which were comparable with the previous UNAIDS assumptions (0.2-1.5 across regions). Model estimates for female partners of MSM were 0.5 (0.2-0.8; n = 20) and 0.3 (0.2-0.4; n = 10) for partners of PWID across settings in Eastern and Southern Africa, lower than the corresponding UNAIDS assumptions (0.9 and 0.8, respectively). The few available model estimates for TGW were higher [5.1 (1.2-7.0; n = 8)] than the UNAIDS assumptions (0.1-0.3). Model estimates for non-FSW partners of FSW clients in Western and Central Africa were high (1.7; 1.0-2.3; n = 29).

CONCLUSIONS

Ratios of new infections among non-KP partners relative to KP were high, confirming the importance of better addressing prevention and treatment needs among KP as central to reducing overall HIV incidence.

Comparison of Empirically Derived and Model-Based Estimates of Key Population HIV Incidence and the Distribution of New Infections by Population Group in Sub-Saharan Africa

BACKGROUND

The distribution of new HIV infections among key populations, including female sex workers (FSWs), gay men and other men who have sex with men (MSM), and people who inject drugs (PWID) are essential information to guide an HIV response, but data are limited in sub-Saharan Africa (SSA). We analyzed empirically derived and mathematical model-based estimates of HIV incidence among key populations and compared with the Joint United Nations Programme on HIV/AIDS (UNAIDS) estimates.

METHODS

We estimated HIV incidence among FSW and MSM in SSA by combining meta-analyses of empirical key population HIV incidence relative to the total population incidence with key population size estimates (KPSE) and HIV prevalence. Dynamic HIV transmission model estimates of HIV incidence and percentage of new infections among key populations were extracted from 94 country applications of 9 mathematical models. We compared these with UNAIDS-reported distribution of new infections, implied key population HIV incidence and incidence-to-prevalence ratios.

RESULTS

Across SSA, empirical FSW HIV incidence was 8.6-fold (95% confidence interval: 5.7 to 12.9) higher than total population female 15-39 year incidence, and MSM HIV incidence was 41.8-fold (95% confidence interval: 21.9 to 79.6) male 15-29 year incidence. Combined with KPSE, these implied 12% of new HIV infections in 2021 were among FSW and MSM (5% and 7% respectively). In sensitivity analysis varying KPSE proportions within 95% uncertainty range, the proportion of new infections among FSW and MSM was between 9% and 19%. Insufficient data were available to estimate PWID incidence rate ratios. Across 94 models, median proportion of new infections among FSW, MSM, and PWID was 6.4% (interquartile range 3.2%-11.7%), both much lower than the 25% reported by UNAIDS.

CONCLUSION

Empirically derived and model-based estimates of HIV incidence confirm dramatically higher HIV risk among key populations in SSA. Estimated proportions of new infections among key populations in 2021 were sensitive to population size assumptions and were substantially lower than estimates reported by UNAIDS.

Study design approaches for future active-controlled HIV prevention trials

Objectives

Vigorous discussions are ongoing about future efficacy trial designs of candidate human immunodeficiency virus (HIV) prevention interventions. The study design challenges of HIV prevention interventions are considerable given rapid evolution of the prevention landscape and evidence of multiple modalities of highly effective products; future trials will likely be 'active-controlled', i.e., not include a placebo arm. Thus, novel design approaches are needed to accurately assess new interventions against these highly effective active controls.

Methods

To discuss active control design challenges and identify solutions, an initial virtual workshop series was hosted and supported by the International AIDS Enterprise (October 2020-March 2021). Subsequent symposia discussions continue to advance these efforts. As the non-inferiority design is an important conceptual reference design for guiding active control trials, we adopt several of its principles in our proposed design approaches.

Results

We discuss six potential study design approaches for formally evaluating absolute prevention efficacy given data from an active-controlled HIV prevention trial including using data from: 1) a registrational cohort, 2) recency assays, 3) an external trial placebo arm, 4) a biomarker of HIV incidence/exposure, 5) an anti-retroviral drug concentration as a mediator of prevention efficacy, and 6) immune biomarkers as a mediator of prevention efficacy.

Conclusions

Our understanding of these proposed novel approaches to future trial designs remains incomplete and there are many future statistical research needs. Yet, each of these approaches, within the context of an active-controlled trial, have the potential to yield reliable evidence of efficacy for future biomedical interventions.

Doxycycline Prophylaxis to Prevent Sexually Transmitted Infections in Women

BACKGROUND

Doxycycline postexposure prophylaxis (PEP) has been shown to prevent sexually transmitted infections (STIs) among cisgender men and transgender women, but data from trials involving cisgender women are lacking.

METHODS

We conducted a randomized, open-label trial comparing doxycycline PEP (doxycycline hyclate, 200 mg taken within 72 hours after condomless sex) with standard care among Kenyan women 18 to 30 years of age who were receiving preexposure prophylaxis against human immunodeficiency virus (HIV). The primary end point was any incident infection with Chlamydia trachomatis, Neisseria gonorrhoeae, or Treponema pallidum. Hair samples were collected quarterly for objective assessment of doxycycline use.

RESULTS

A total of 449 participants underwent randomization; 224 were assigned to the doxycycline-PEP group and 225 to the standard-care group. Participants were followed quarterly over 12 months. A total of 109 incident STIs occurred (50 in the doxycycline-PEP group [25.1 per 100 person-years] and 59 in the standard-care group [29.0 per 100 person-years]), with no significant between-group difference in incidence (relative risk, 0.88; 95% confidence interval [CI], 0.60 to 1.29; P = 0.51). Among the 109 incident STIs, chlamydia accounted for 85 (78.0%) (35 in the doxycycline-PEP group and 50 in the standard-care group; relative risk, 0.73; 95% CI, 0.47 to 1.13). No serious adverse events were considered by the trial investigators to be related to doxycycline, and there were no incident HIV infections. Among 50 randomly selected participants in the doxycycline-PEP group, doxycycline was detected in 58 of 200 hair samples (29.0%). All N. gonorrhoeae-positive isolates were resistant to doxycycline.

CONCLUSIONS

Among cisgender women, the incidence of STIs was not significantly lower with doxycycline PEP than with standard care. According to hair-sample analysis, the use of doxycycline PEP among those assigned to receive it was low. (Funded by the National Institutes of Health; dPEP ClinicalTrials.gov number, NCT04050540.).

Durability of single-dose HPV vaccination in young Kenyan women: randomized controlled trial 3-year results

Cervical cancer burden is high where prophylactic vaccination and screening coverage are low. We demonstrated in a multicenter randomized, double-blind, controlled trial that single-dose human papillomavirus (HPV) vaccination had high vaccine efficacy (VE) against persistent infection at 18 months in Kenyan women. Here, we report findings of this trial through 3 years of follow-up. Overall, 2,275 healthy women aged 15-20 years were recruited and randomly assigned to receive bivalent (n = 760), nonavalent (n = 758) or control (n = 757) vaccine. The primary outcome was incident-persistent vaccine type-specific cervical HPV infection. The primary evaluation was superiority analysis in the modified intention-to-treat (mITT) HPV 16/18 and HPV 16/18/31/33/45/52/58 cohorts. The trial met its prespecified end points of vaccine type-specific persistent HPV infection. A total of 75 incident-persistent infections were detected in the HPV 16/18 mITT cohort: 2 in the bivalent group, 1 in the nonavalent group and 72 in the control group. Nonavalent VE was 98.8% (95% CI 91.3-99.8%, P < 0.0001) and bivalent VE was 97.5% (95% CI 90.0-99.4%, P < 0.0001). Overall, 89 persistent infections were detected in the HPV 16/18/31/33/45/52/58 mITT cohort: 5 in the nonavalent group and 84 in the control group; nonavalent VE was 95.5% (95% CI 89.0-98.2%, P < 0.0001). There were no vaccine-related severe adverse events. Three years after vaccination, single-dose HPV vaccination was highly efficacious, safe and conferred durable protection. ClinicalTrials.gov no. NCT03675256 .

Efficacy and safety of long-acting cabotegravir compared with daily oral tenofovir disoproxil fumarate plus emtricitabine to prevent HIV infection in cisgender men and transgender women who have sex with men 1 year after study unblinding: a secondary analysis of the phase 2b and 3 HPTN 083 randomised controlled trial

BACKGROUND

Injectable cabotegravir was superior to daily oral tenofovir disoproxil fumarate plus emtricitabine for HIV prevention in two clinical trials. Both trials had the primary aim of establishing the HIV prevention efficacy of long-acting injectable cabotegravir pre-exposure prophylaxis (PrEP) compared with tenofovir disoproxil fumarate plus emtricitabine daily oral PrEP. Long-acting PrEP was associated with diagnostic delays and integrase strand-transfer inhibitor (INSTI) resistance. This report presents findings from the first unblinded year of the HIV Prevention Trials Network (HPTN) 083 study.

METHODS

The HPTN 083 randomised controlled trial enrolled HIV-uninfected cisgender men and transgender women at elevated HIV risk who have sex with men, from 43 clinical research sites in Africa, Asia, Latin America, and the USA. Inclusion criteria included: a negative HIV serological test at the screening and study entry, undetectable HIV RNA levels within 14 days of study entry, age 18 years or older, overall good health as determined by clinical and laboratory evaluations, and a creatinine clearance of 60 mL/min or higher. Participants were randomly allocated to receive long-acting injectable cabotegravir or daily oral tenofovir disoproxil fumarate plus emtricitabine PrEP. After study unblinding, participants remained on their original regimen awaiting an extension study. HIV infections were characterised retrospectively at a central laboratory. Here we report the secondary analysis of efficacy and safety for the first unblinded year. The primary outcome was incident HIV infection. Efficacy analyses were done on the modified intention-to-treat population using a Cox regression model. Adverse events were compared across treatment groups and time periods (blinded vs unblinded). This trial is registered with ClinicalTrials.gov, NCT02720094.

FINDINGS

Of the 4488 participants who contributed person-time to the blinded analysis, 3290 contributed person-time to the first unblinded year analysis between May 15, 2020, and May 14, 2021. Updated HIV incidence in the blinded phase was 0·41 per 100 person-years for long-acting injectable cabotegravir PrEP and 1·29 per 100 person-years for daily oral tenofovir disoproxil fumarate plus emtricitabine PrEP (hazard ratio [HR] 0·31 [95% CI 0·17-0·58], p=0·0003). HIV incidence in the first unblinded year was 0·82 per 100 person-years for long-acting PrEP and 2·27 per 100 person-years for daily oral PrEP (HR 0·35 [0·18-0·69], p=0·002). Adherence to both study products decreased after study unblinding. Additional infections in the long-acting PrEP group included two with on-time injections; three with one or more delayed injections; two detected with long-acting PrEP reinitiation; and 11 more than 6 months after their last injection. Infection within 6 months of cabotegravir exposure was associated with diagnostic delays and INSTI resistance. Adverse events were generally consistent with previous reports; incident hypertension in the long-acting PrEP group requires further investigation.

INTERPRETATION

Long-acting injectable cabotegravir PrEP retained high efficacy for HIV prevention in men and transgender women who have sex with men during the first year of open-label follow-up, with a near-identical HR for HIV risk reduction between long-acting injectable cabotegravir and daily oral tenofovir disoproxil fumarate plus emtricitabine PrEP during the first year after unblinding compared with the blinded period. Extended follow-up further defined the risk period for diagnostic delays and emergence of INSTI resistance.

FUNDING

Division of AIDS at the National Institute of Allergy and Infectious Diseases, ViiV Healthcare, and Gilead Sciences.

Adults on pre-exposure prophylaxis (tenofovir-emtricitabine) have faster clearance of anti-HIV monoclonal antibody VRC01

Broadly neutralizing monoclonal antibodies (mAbs) are being developed for HIV-1 prevention. Hence, these mAbs and licensed oral pre-exposure prophylaxis (PrEP) (tenofovir-emtricitabine) can be concomitantly administered in clinical trials. In 48 US participants (men and transgender persons who have sex with men) who received the HIV-1 mAb VRC01 and remained HIV-free in an antibody-mediated-prevention trial (ClinicalTrials.gov #NCT02716675), we conduct a post-hoc analysis and find that VRC01 clearance is 0.08 L/day faster (p = 0.005), and dose-normalized area-under-the-curve of VRC01 serum concentration over-time is 0.29 day/mL lower (p < 0.001) in PrEP users (n = 24) vs. non-PrEP users (n = 24). Consequently, PrEP users are predicted to have 14% lower VRC01 neutralization-mediated prevention efficacy against circulating HIV-1 strains. VRC01 clearance is positively associated (r = 0.33, p = 0.03) with levels of serum intestinal Fatty Acid Binding protein (I-FABP), a marker of epithelial intestinal permeability, which is elevated upon starting PrEP (p = 0.04) and after months of self-reported use (p = 0.001). These findings have implications for the evaluation of future HIV-1 mAbs and postulate a potential mechanism for mAb clearance in the context of PrEP.

Efficacy, safety, tolerability, and pharmacokinetics of long-acting injectable cabotegravir for HIV pre-exposure prophylaxis in transgender women: a secondary analysis of the HPTN 083 trial

BACKGROUND

The HIV Prevention Trials Network (HPTN) 083 trial showed that long-acting injectable cabotegravir was more effective than tenofovir disoproxil fumarate plus emtricitabine in preventing HIV in cisgender men and transgender women who have sex with men. We aimed to characterise the cohort of transgender women included in HPTN 083.

METHODS

HPTN 083 is an ongoing, phase 2b/3, randomised, multicentre, double-blind, double-dummy clinical trial done at 43 sites in seven countries (Argentina, Brazil, Peru, the USA, South Africa, Thailand, and Viet Nam). HIV-negative participants were randomly assigned (1:1) to receive injectable cabotegravir or tenofovir disoproxil fumarate plus emtricitabine. The study design and primary outcomes of the blinded phase of HPTN 083 have already been reported. An enrolment minimum of 10% transgender women was set for the trial. Here we characterise the cohort of transgender women enrolled from Dec 6, 2016, to May 14, 2020, when the study was unblinded. We report sociodemographic characteristics, use of gender affirming hormone therapy, and behavioural assessments of the transgender women participants. Laboratory testing and safety evaluations are also reported. The trial is registered at ClinicalTrials.gov, NCT02720094.

FINDINGS

HPTN 083 enrolled 570 transgender women (304 tenofovir disoproxil fumarate plus emtricitabine; 266 injectable cabotegravir). Transgender women were primarily from Asia (225 [39%]) and Latin America (205 [36%]); 330 (58%) reported using gender affirming hormone therapy. Intimate partner violence was common (270 [47%] reported emotional abuse and 172 [30%] reported physical abuse) and 323 (57%) reported a history of childhood sexual abuse. 159 (28%) transgender women disagreed that they were at risk for HIV, and 142 (25%) screened positive for depressive symptoms. During study follow-up, incidence of syphilis was 16·25% (95% CI 13·28-19·69), rectal gonorrhoea was 11·66% (9·14-14·66), and chlamydia was 20·61% (17·20-24·49). Frequency of adverse events was similar between the treatment groups. Nine seroconversions occurred among transgender women during the blinded phase of the study (seven in the tenofovir disoproxil fumarate plus emtricitabine group and two in the injectable cabotegravir group); overall incidence was 1·19 per 100 person-years (95% CI 0·54-2·25): 1·80 per 100 person-years (0·73-3·72) in the tenofovir disoproxil fumarate plus emtricitabine group and 0·54 per 100 person-years (0·07-1·95) in the injectable cabotegravir group (hazard ratio 0·34 [95% CI 0·08-1·56]). Cabotegravir concentrations did not differ by gender affirming hormone therapy use.

INTERPRETATION

HIV prevention strategies for transgender women cannot be addressed separately from social and structural vulnerabilities. Transgender women were well represented in HPTN 083 and should continue to be prioritised in HIV prevention studies. Our results suggest that injectable cabotegravir is a safe and effective pre-exposure prophylaxis option for transgender women.

FUNDING

National Institute of Allergy and Infectious Diseases and ViiV Healthcare.

High prevalence and incidence of gonorrhoea and chlamydia in young women eligible for HIV pre-exposure prophylaxis in South Africa and Zimbabwe: results from the HPTN 082 trial

INTRODUCTION

We investigated the prevalence, incidence and factors associated with sexually transmitted infections (STIs) among young African women seeking HIV pre-exposure prophylaxis (PrEP).

METHODS

HPTN 082 was a prospective, open-label PrEP study enrolling HIV-negative sexually active women aged 16-25 years in Cape Town and Johannesburg, South Africa, and Harare, Zimbabwe. Endocervical swabs from enrolment, months 6 and 12 were tested for Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) by nucleic acid amplification, and Trichomonas vaginalis (TV) by a rapid test. Intracellular tenofovir-diphosphate (TFV-DP) concentrations in dried blood spots were measured at months 6 and 12. Associations between risk characteristics and STI outcomes were assessed using Poisson regression.

RESULTS

Of 451 enrolled participants, 55% had an STI detected at least once. CT incidence was 27.8 per 100 person-years (py) (95% CI 23.1, 33.2), GC incidence was 11.4 per 100 py (95% CI 8.5, 15.0) and TV incidence was 6.7 per 100 py (95% CI 4.5, 9.5). 66% of incident infections were diagnosed in women uninfected at baseline. Baseline cervical infection (GC or CT) risk was highest in Cape Town (relative risk (RR) 2.38, 95% CI 1.35, 4.19) and in those not living with family (RR 1.87, 95% 1.13, 3.08); condom use was protective (RR 0.67, 95% CI 0.45, 0.99). Incident CT was associated with baseline CT (RR 2.01; 95% CI 1.28, 3.15) and increasing depression score (RR 1.05; 95% CI 1.01, 1.09). Incident GC was higher in Cape Town (RR 2.40; 95% CI 1.18, 4.90) and in participants with high PrEP adherence (TFV-DP concentrations ≥700 fmol/punch) (RR 2.04 95% CI 1.02, 4.08).

CONCLUSION

Adolescent girls and young women seeking PrEP have a high prevalence and incidence of curable STIs. Alternatives to syndromic management for diagnosis and treatment are needed to reduce the burden of STIs in this population.

TRIAL REGISTRATION NUMBER

NCT02732730.

Population-level analysis of natural control of HIV infection in Zambia and South Africa: HPTN 071 (PopART)

INTRODUCTION

HIV controllers have low viral loads (VL) without antiretroviral treatment (ART). We evaluated viraemic control in a community-randomized trial conducted in Zambia and South Africa that evaluated the impact of a combination prevention intervention on HIV incidence (HPTN 071 [PopART]; 2013-2018).

METHODS

VL and antiretroviral (ARV) drug testing were performed using plasma samples collected 2 years after enrolment for 4072 participants who were HIV positive at the start of the study intervention. ARV drug use was assessed using a qualitative laboratory assay that detects 22 ARV drugs in five drug classes. Participants were classified as non-controllers if they had a VL ≥2000 copies/ml with no ARV drugs detected at this visit. Additional VL and ARV drug testing was performed at a second annual study visit to confirm controller status. Participants were classified as controllers if they had VLs <2000 with no ARV drugs detected at both visits. Non-controllers who had ARV drugs detected at either visit were excluded from the analysis to minimize potential confounders associated with ARV drug access and uptake.

RESULTS

The final cohort included 126 viraemic controllers and 766 non-controllers who had no ARV drugs detected. The prevalence of controllers among the 4072 persons assessed was 3.1% (95% confidence interval [CI]: 2.6%, 3.6%). This should be considered a minimum estimate, since high rates of ARV drug use in the parent study limited the ability to identify controllers. Among the 892 participants in the final cohort, controller status was associated with biological sex (female > male, p = 0.027). There was no significant association between controller status and age, study country or herpes simplex virus type 2 (HSV-2) status at study enrolment.

CONCLUSIONS

To our knowledge, this report presents the first large-scale, population-level study evaluating the prevalence of viraemic control and associated factors in Africa. A key advantage of this study was that a biomedical assessment was used to assess ARV drug use (vs. self-reported data). This study identified a large cohort of HIV controllers and non-controllers not taking ARV drugs, providing a unique repository of longitudinal samples for additional research. This cohort may be useful for further studies investigating the mechanisms of virologic control.

Perspectives on Design Approaches for HIV Prevention Efficacy Trials

The challenge of designing future HIV prevention efficacy trials in a rapidly evolving HIV prevention landscape was explored through a series of virtual stakeholder's engagement meetings convened online between October 2020 and April 2021. A broad array of stakeholders from the HIV prevention research community reviewed current trial designs and lessons learned, explored issues specific to unique product classes, and concluded with specialist-focused examinations of statistical design concepts and the importance of community engagement in research. The aim was to reflect on current approaches and evaluate new trial design approaches for evaluating efficacy of a candidate prevention strategy in the context of an active-controlled trial, which does not include a placebo arm. In this report, we provide a summary of the discussion points that included gaps in understanding and logical next steps in the prevention research pathway. The technical challenges involved in the statistical design approaches are described in a companion article.

Partner testing with HIV self-test distribution by Ugandan pregnant women living with HIV: a randomized trial

INTRODUCTION

Secondary distribution of HIV self-tests (HIVST) by HIV-negative pregnant women to male partners increases men's testing rates. We examined whether this strategy promotes male partner testing for pregnant women living with HIV (PWLHIV).

METHODS

We conducted an open-label individually randomized trial in Kampala, Uganda, in which PWLHIV ≥18 years who reported a partner of unknown HIV status were randomized 2:1 to secondary distribution of HIVST for male partner(s) or standard-of-care (SOC; invitation letter to male partner for fast-track testing). Women were followed until 12 months post-partum. Male partners were offered confirmatory HIV testing and facilitated linkage to antiretroviral treatment (ART) or oral pre-exposure prophylaxis (PrEP). Using intention-to-treat analysis, primary outcomes were male partner testing at the clinic and initiation on PrEP or ART evaluated through 12 months post-partum (ClinicalTrials.gov, NCT03484533).

RESULTS

From November 2018 to March 2020, 500 PWLHIV were enrolled with a median age of 27 years (interquartile range [IQR] 23-30); 332 were randomized to HIVST and 168 to SOC with 437 PWLHIV (87.4%) completing 12 months follow-up post-partum. Of 236 male partners who tested at the clinic and enrolled (47.2%), their median age was 31 years (IQR 27-36), 45 (88.3%) men with HIV started ART and 113 (61.1%) HIV-negative men started PrEP. There was no intervention effect on male partner testing (hazard ratio [HR] 1.04; 95% confidence interval [CI]: 0.79-1.37) or time to ART or PrEP initiation (HR 0.96; 95% CI: 0.69-1.33). Two male partners and two infants acquired HIV for an incidence of 0.99 per 100 person-years (95% CI: 0.12-3.58) and 1.46 per 100 person-years (95% CI: 0.18%-5.28%), respectively. Social harms related to study participation were experienced by six women (HIVST = 5, SOC = 1).

CONCLUSIONS

Almost half of the partners of Ugandan PWLHIV tested for HIV with similar HIV testing rates and linkage to ART or PrEP among the secondary distribution of HIVST and SOC arms. Although half of men became aware of their HIV serostatus and linked to services, additional strategies to reach male partners of women in antenatal care are needed to increase HIV testing and linkage to services among men.

Community- and individual-level correlates of HIV incidence in HPTN 071 (PopART)

INTRODUCTION

Universal HIV testing and treatment aims to identify all people living with HIV and offer them treatment, decreasing the number of individuals with unsuppressed HIV and thus reducing HIV transmission. Longitudinal follow-up of individuals with and without HIV in a cluster-randomized trial of communities allowed for the examination of community- and individual-level measures of HIV risk and HIV incidence.

METHODS

HPTN 071 (PopART) was a three-arm cluster-randomized trial conducted between 2013 and 2018 that evaluated the use of two combination HIV prevention strategies implemented at the community level to reduce HIV incidence compared to the standard of care. The trial, conducted in 21 communities in Zambia and South Africa, measured HIV incidence over 36 months in a population cohort of ∼2000 randomly selected adults per community aged 18-44. Multilevel models were used to assess the association between HIV incidence and community- and individual-level socio-demographic and behavioural risk factors, as well as prevalence of detectable virus (PDV) defined as the estimated proportion of the community with unsuppressed viral load.

RESULTS

Overall HIV incidence was 1.49/100 person-years. Communities with less financial wealth and communities with more individuals reporting having sex partners outside of the community or two or more sexual partners had higher HIV incidence. PDV at 2 years of study was 6.8% and was strongly associated with HIV incidence: for every 50% relative reduction in community PDV, there was a 49% (95% confidence interval [CI]: 37%-58%, p < 0.001) relative decrease in HIV incidence. At the individual level; socio-economic status, AUDIT score, medical male circumcision and certain sexual behaviours were associated with HIV risk.

CONCLUSIONS

Using data from the PopART randomized trial, we found several associations of HIV incidence with community-level measures reflecting the sexual behaviour and socio-economic make-up of each community. We also found a strong association between community PDV and HIV incidence supporting the use of PDV as a tool for monitoring progress in controlling the epidemic. Lastly, we found significant individual-level factors of HIV risk that are generally consistent with previous HIV epidemiological research. These results have the potential to identify high high-incidence communities, inform structural-level interventions, and optimize individual-level interventions for HIV prevention.

CLINICAL TRIAL NUMBER

ClinicalTrials.gov number, NCT01900977, HPTN 071 [PopArt].

A decision support tool has similar high PrEP uptake and increases early PrEP persistence in adolescent girls and young women in South Africa: results from a randomized controlled trial

INTRODUCTION

African adolescent girls and young women (AGYW) have high rates of HIV acquisition and are a priority population for HIV pre-exposure prophylaxis (PrEP). PrEP implementation has been limited by AGYW's low perceived HIV risk and provider demands. A decision support tool (DST) with information about PrEP could improve clients' risk perception, knowledge about PrEP, informed decision-making and motivation to use PrEP based on their risk, facilitating PrEP delivery in primary healthcare (PHC) clinics.

METHODS

We designed MyPrEP, a client-facing DST about PrEP and HIV prevention, with youth-friendly information and images. The impact of the MyPrEP tool was assessed among HIV-negative women aged 18-25 years presenting to a PHC clinic in Johannesburg, South Africa from March 2019 to 2020. AGYW were randomized by day to the DST or a general health website as the control condition. A clinician blinded to DST versus control allocation provided standard of care counselling about PrEP, offered PrEP, administered a questionnaire and conducted sexually transmitted infection testing. The primary outcome was PrEP initiation and the secondary outcome was PrEP persistence at 1 month, determined by pharmacy dispensation records.

RESULTS

Of 386 AGYW screened, 353 were randomized (DST n = 172, control n = 181) with a median age of 21 years (interquartile range [IQR] 20, 23) and 56% (199/353) attending the clinic for HIV testing, 46% (164/353) using contraception, 15% (53/353) using condoms consistently and 37% (108/353) with a curable sexually transmitted infection. PrEP was initiated by 97% in the DST group and 94% in the control group (OR 1.79; 95% confidence interval, CI = 0.79-1.53), of whom two-thirds planned to continue PrEP until they decided if they liked PrEP. At 1 month, PrEP persistence was 19% in the DST and 10% in the control group (OR 1.97, 95% CI 1.08-3.69). Ninety-nine percent randomized to the DST reported satisfaction with MyPrEP.

CONCLUSIONS

Among AGYW attending a South African PHC clinic, PrEP uptake was >90% with two-fold higher PrEP persistence at 1 month in those randomized to use the MyPrEP DST. Given the need for strategies to support PrEP implementation and improve low PrEP persistence among African AGYW, a PrEP DST warrants further evaluation.

Predictors of participant retention in a community-based HIV prevention cohort: perspectives from the HPTN 071 (PopART) study

INTRODUCTION

In 2021, there were 38.4 million people living with HIV (PLHIV) globally, of which 20.6 million (54%) were living in Eastern and Southern Africa. Longitudinal studies, inclusive of community randomized trials (CRTs), provide critical evidence to guide a broad range of health care interventions including HIV prevention. In this study, we have used an individual-level cohort study design to evaluate the association between sex and other baseline characteristics and participant retention in the HPTN 071 (PopART) trial in Zambia and South Africa.

METHODS

HPTN 071 (PopART) was a community randomized trial (CRT) conducted from 2013 to 2018, in 21 communities. The primary outcome was measured in a randomly selected population cohort (PC), followed up over 3 to 4 years at annual rounds. PC retention was defined as completion of an annual follow-up questionnaire. Baseline characteristics were described by study arm and Poisson regression analyses used to measure the association between baseline factors and retention. In addition, we present a description of researcher-documented reasons for study withdrawal by PC participants.

RESULTS

Of the 38,474 participants enrolled during the first round of the trial (PC0), most were women (27,139, 71%) and 73% completed at least one follow-up visit. Retention was lower in men (adj RR: 0.90; 95% CI: 0.88, 0.91) and higher among older participants (adj RR: 1.23; 95% CI 1.20, 1.26) when comparing ages 35-44 to 18-24 years. Retention was higher among individuals with high socioeconomic status (SES) (adj RR 1.16; 95% CI 1.14, 1.19) and medium SES (adj RR 1.12; 95% CI 1.09, 1.14) compared to low SES. The most common reasons for study withdrawal were study refusal (23%) and relocation outside the CRT catchment area (66%).

CONCLUSION

Despite challenges, satisfactory retention outcomes were achieved in PopART with limited variability across study arms. In keeping with other studies, younger age, male sex, and lower SES were associated with lower levels of retention. Relocation outside of catchment area was the most common reason for non-retention in this CRT.

Characteristics of Kenyan women using HIV PrEP enrolled in a randomized trial on doxycycline postexposure prophylaxis for sexually transmitted infection prevention

INTRODUCTION

The global incidence of sexually transmitted infections (STIs) has been rapidly increasing over the past decade, with more than one million curable STIs being acquired daily. Young women in sub-Saharan Africa have a high prevalence and incidence of both curable STIs and HIV. The use of doxycycline as a prophylaxis to prevent STIs is promising; however, clinical trials, to date, have only been conducted among men who have sex with men (MSM) in high-income settings. We describe the characteristics of participants enrolled in the first trial to determine the efficacy of doxycycline post-exposure prophylaxis (PEP) to reduce STI incidence among women taking daily, oral HIV pre-exposure prophylaxis (PrEP).

METHODS

This is an open-label 1:1 randomized clinical trial on the efficacy of doxycycline PEP compared with standard of care (e.g., quarterly STI screening and treatment) to reduce incident bacterial STIs - Neisseria gonorrhoeae, Chlamydia trachomatis, and Treponema pallidum - among Kenyan women aged ≥18 and ≤30 years. All were also taking HIV pre-exposure prophylaxis (PrEP). We describe the baseline characteristics, STI prevalence, and STI risk perception of participants.

RESULTS

Between February 2020 and November 2021, 449 women were enrolled. The median age was 24 years (IQR 21-27), the majority were never married (66.1%), 370 women (82.4%) reported having a primary sex partner, and 33% had sex with new partners in the three months prior to enrolment. Two-thirds (67.5%, 268 women) did not use condoms, 36.7% reported transactional sex, and 43.2% suspected their male partners of having sex with other women. Slightly less than half (45.9%, 206 women) were recently concerned about being exposed to an STI. The prevalence of STIs was 17.9%, with C. trachomatis accounting for the majority of infections. Perceived risk of STIs was not associated with the detection of an STI.

CONCLUSION

Young cisgender women using HIV PrEP in Kenya and enrolled in a trial of doxycycline postexposure prophylaxis had a high prevalence of curable STIs and represent a target population for an STI prevention intervention.

Counterfactual estimation of efficacy against placebo for novel PrEP agents using external trial data: example of injectable cabotegravir and oral PrEP in women

INTRODUCTION

Multiple antiretroviral agents have demonstrated efficacy for human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP). As a result, clinical trials of novel agents have transitioned from placebo- to active-controlled designs; however, active-controlled trials do not provide an estimate of efficacy versus no use of PrEP. Counterfactual placebo comparisons using other data sources could be employed to provide this information.

METHODS

We compared the active-controlled study (HPTN 084) of injectable cabotegravir (CAB-LA) versus daily oral emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) among women from seven countries in Africa to three external, contemporaneous randomized HIV prevention trials from which we constructed counterfactual placebo estimates. We used direct standardization via analysis weights to achieve the same distribution of person-years between the external study and HPTN 084, across strata predictive of HIV risk (country and selected risk covariates). We estimated prevention efficacy against a counterfactual placebo to provide information on the use of CAB-LA and FTC/TDF compared to no intervention. We compared the counterfactual placebo findings for FTC/TDF to previous placebo-controlled trials, adjusted for observed adherence to daily pills.

RESULTS

Distribution of age and baseline prevalence of gonorrhoea and chlamydia were similar among matched counterfactual placebo and observed HPTN 084 arms after standardization. Counterfactual estimates of CAB-LA versus placebo in all three settings showed a consistent risk reduction of 93%-94%, with lower bounds of the confidence intervals above 72%. Observed adherence (quantifiable tenofovir in plasma) in HPTN 084 was 54%-56%, and estimated efficacy of daily oral FTC/TDF against a counterfactual placebo was consistent with a predicted risk reduction of 39%-40% for this level of daily pill use.

CONCLUSIONS

Counterfactual placebo rates of HIV acquisition derived from external trial data in similar locations and time can be used to support estimates of placebo-based efficacy of a novel HIV prevention agent. External trial data must be standardized to be representative of the clinical trial cohort testing the novel HIV prevention agent, accounting for confounders.

Trust in the provider and accurate self-reported PrEP adherence among adolescent girls and young women in South Africa and Zimbabwe: HPTN 082 study

BACKGROUND

Trust is an important cornerstone of patient-provider communication. Accurate reporting of pre-exposure prophylaxis (PrEP) adherence is vital for providers to determine who needs adherence support, especially adolescent girls and young women (AGYW) disproportionately affected by newly diagnosed HIV.

METHODS

This is a secondary analysis of the HPTN 082 open-label PrEP demonstration trial. From 2016-2018, 451 AGYW aged 16-25 years were enrolled in South Africa (Cape Town and Johannesburg) and Zimbabwe (Harare). PrEP was initiated by 427, and 354 (83%) had month three patient-reported adherence responses and intracellular tenofovir diphosphate (TFV-DP) measurements. The patient-reported adherence response to 'In the past month, how often did you take the tablet?' was dichotomized as 'high' if the response was every day or most days, and 'low' if some days or not many days or never. The biomarker marker evidence of adherence in dried blood spots was defined as 'high' if TFV-DP ≥ 700, and 'low' if < 350 fmol/punch. We used multinomial logistic regression to examine if trust in the PrEP provider was associated with concordance between patient-reported adherence and intracellular tenofovir-diphosphate (TFV-DP).

RESULTS

AGYW who reported trust in their providers were almost four-fold (aOR 3.72, 95% CI 1.20-11.51) more likely to have concordant adherence (high self-reported adherence and high TFV-DP concentrations) compared to discordant non-adherence (high self-reported adherence and low TFV-DP concentrations).

CONCLUSION

Education and training of providers to build trusting relationships with AGYW may lead to more accurate reporting of PrEP adherence. With accurate reporting, adequate support can be provided to bolster adherence.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02732730.

Postexposure Doxycycline to Prevent Bacterial Sexually Transmitted Infections

BACKGROUND

Interventions to reduce sexually transmitted infections (STIs) among men who have sex with men (MSM) are needed.

METHODS

We conducted an open-label, randomized study involving MSM and transgender women who were taking preexposure prophylaxis (PrEP) against human immunodeficiency virus (HIV) infection (PrEP cohort) or living with HIV infection (persons living with HIV infection [PLWH] cohort) and who had had Neisseria gonorrhoeae (gonorrhea), Chlamydia trachomatis (chlamydia), or syphilis in the past year. Participants were randomly assigned in a 2:1 ratio to take 200 mg of doxycycline within 72 hours after condomless sex (doxycycline postexposure prophylaxis) or receive standard care without doxycycline. STI testing was performed quarterly. The primary end point was the incidence of at least one STI per follow-up quarter.

RESULTS

Of 501 participants (327 in the PrEP cohort and 174 in the PLWH cohort), 67% were White, 7% Black, 11% Asian or Pacific Islander, and 30% Hispanic or Latino. In the PrEP cohort, an STI was diagnosed in 61 of 570 quarterly visits (10.7%) in the doxycycline group and 82 of 257 quarterly visits (31.9%) in the standard-care group, for an absolute difference of -21.2 percentage points and a relative risk of 0.34 (95% confidence interval [CI], 0.24 to 0.46; P<0.001). In the PLWH cohort, an STI was diagnosed in 36 of 305 quarterly visits (11.8%) in the doxycycline group and 39 of 128 quarterly visits (30.5%) in the standard-care group, for an absolute difference of -18.7 percentage points and a relative risk of 0.38 (95% CI, 0.24 to 0.60; P<0.001). The incidences of the three evaluated STIs were lower with doxycycline than with standard care; in the PrEP cohort, the relative risks were 0.45 (95% CI, 0.32 to 0.65) for gonorrhea, 0.12 (95% CI, 0.05 to 0.25) for chlamydia, and 0.13 (95% CI, 0.03 to 0.59) for syphilis, and in the PLWH cohort, the relative risks were 0.43 (95% CI, 0.26 to 0.71), 0.26 (95% CI, 0.12 to 0.57), and 0.23 (95% CI, 0.04 to 1.29), respectively. Five grade 3 adverse events and no serious adverse events were attributed to doxycycline. Of the participants with gonorrhea culture available, tetracycline-resistant gonorrhea occurred in 5 of 13 in the doxycycline groups and 2 of 16 in the standard-care groups.

CONCLUSIONS

The combined incidence of gonorrhea, chlamydia, and syphilis was lower by two thirds with doxycycline postexposure prophylaxis than with standard care, a finding that supports its use among MSM with recent bacterial STIs. (Funded by the National Institutes of Health; DoxyPEP ClinicalTrials.gov number, NCT03980223.).

Uptake of medical male circumcision with household-based testing, and the association of traditional male circumcision and HIV infection

OBJECTIVES

Voluntary medical male circumcision (VMMC) is an important component of combination HIV prevention. Inclusion of traditionally circumcised HIV negative men in VMMC uptake campaigns may be important if traditional male circumcision is less protective against HIV acquisition than VMMC.

METHODS

We used data from the HIV Prevention Trials Network (HPTN) 071 (PopART) study. This cluster-randomized trial assessed the impact of a combination prevention package on population-level HIV incidence in 21 study communities in Zambia and South Africa. We evaluated uptake of VMMC, using a two-stage analysis approach and used discrete-time survival analysis to evaluate the association between the types of male circumcision and HIV incidence.

RESULTS

A total of 10 803 HIV-negative men with self-reported circumcision status were included in this study. At baseline, 56% reported being uncircumcised, 26% traditionally circumcised and 18% were medically circumcised. During the PopART intervention, 11% of uncircumcised men reported uptake of medical male circumcision. We found no significant difference in the uptake of VMMC in communities receiving the PopART intervention package and standard of care {adj. rate ratio=1·10 [95% confidence interval (CI) 0.82, 1.50, P  = 0.48]}. The rate of HIV acquisition for medically circumcised men was 70% lower than for those who were uncircumcised adjusted hazard ratio (adjHR) = 0.30 (95% CI 0.16-0.55; P  < 0.0001). There was no difference in rate of HIV acquisition for traditionally circumcised men compared to those uncircumcised adjHR = 0.84 (95% CI 0.54, 1.31; P  = 0.45).

CONCLUSIONS

Household-based delivery of HIV testing followed by referral for medical male circumcision did not result in substantial VMMC uptake. Traditional circumcision is not associated with lower risk of HIV acquisition.

ADAPTIVE TIME LOCATION SAMPLING FOR COMPASS, A SARS-COV-2 PREVALENCE STUDY IN FIFTEEN DIVERSE COMMUNITIES IN THE UNITED STATES

The COVPN 5002 (COMPASS) study aimed to estimate the prevalence of SARS-CoV-2 (active SARS-CoV-2 or prior SARS-CoV-2 infection) in children and adults attending public venues in 15 socio-demographically diverse communities in the United States. To protect against potential challenges in implementing traditional sampling strategies, time-location sampling (TLS) using complex sampling involving stratification, clustering of units, and unequal probabilities of selection was used to recruit individuals from neighborhoods in selected communities. The innovative design adapted to constraints such as closure of venues; changing infection hotspots; and uncertain policies. Recruitment of children and the elderly raised additional challenges in sample selection and implementation. To address these challenges, the TLS design adaptively updated both the sampling frame and the selection probabilities over time using information acquired from prior weeks. Although the study itself was specific to COVID-19, the strategies presented in this paper could serve as a case study that can be adapted for performing rigorous population-level inferences in similar settings and could help inform rapid and effective responses to future global public health challenges.

Facilitating Next-Generation Pre-Exposure Prophylaxis Clinical Trials Using HIV Recent Infection Assays: A Consensus Statement from the Forum HIV Prevention Trial Design Project

Standard-of-care HIV pre-exposure prophylaxis (PrEP) is highly efficacious, but uptake of and persistence on a daily oral pill is low in many settings. Evaluation of alternate PrEP products will require innovation to avoid the unpractically large sample sizes in noninferiority trials. We propose estimating HIV incidence in people not on PrEP as an external counterfactual to which on-PrEP incidence in trial subjects can be compared. HIV recent infection testing algorithms (RITAs), such as the limiting antigen avidity assay plus viral load used on specimens from untreated HIV positive people identified during screening, is one possible approach. Its feasibility is partly dependent on the sample size needed to ensure adequate power, which is impacted by RITA performance, the number of recent infections identified, the expected efficacy of the intervention, and other factors. Screening sample sizes to support detection of an 80% reduction in incidence for 3 key populations are more modest, and comparable to the number of participants in recent phase III PrEP trials. Sample sizes would be significantly larger in populations with lower incidence, where the false recency rate is higher or if PrEP efficacy is expected to be lower. Our proposed counterfactual approach appears to be feasible, offers high statistical power, and is nearly contemporaneous with the on-PrEP population. It will be important to monitor the performance of this approach during new product development for HIV prevention. If successful, it could be a model for preventive HIV vaccines and prevention of other infectious diseases.

Viral suppression and self-reported ART adherence after 3 years of universal testing and treatment in the HPTN 071 (PopART) community-randomised trial in Zambia and South Africa: a cross-sectional analysis

BACKGROUND

In 2014, UNAIDS set the target that 90% of individuals on antiretroviral therapy (ART) be virally suppressed. Here, we use data from the HPTN 071 (PopART) trial to report whether the introduction of universal testing and treatment has affected viral suppression or treatment adherence among individuals who self-reported they were taking ART, and identify risk factors for these outcomes.

METHODS

This was a cross-sectional study nested within the randomly selected population cohort of the PopART trial. The trial took place in 21 communities in Zambia and South Africa. Analyses included 3570 HIV-positive participants who were seen at the second follow-up visit in 2016-17 and who self-reported that they were currently taking ART. Viral suppression was defined as HIV RNA of less than 400 copies per mL from a blood sample collected during the cohort visit, and ART adherence was measured using self-reporting (reported as no missed pills in last 7 days). Prevalences of these outcomes were compared across three trial arms using a two-stage approach suitable for clustered data. Each arm consisted of seven communities, with one arm receiving a combination HIV prevention package including immediate ART initiation, one receiving a combination HIV prevention package excluding immediate ART initiation and one arm receving standard of care. Risk factors for each of the outcomes were assessed using logistic regression.

FINDINGS

Among the 3570 participants who self-reported that they were currently on ART, 416 (11·7%) of 3554 were not virally suppressed (16 were missing viral suppression status) and 345 (9·7%) of 3566 reported being non-adherent to ART (four were missing adherence status). The proportion not virally suppressed was higher in communities in South Africa (195 [16·4%] of 1191) than in Zambia (221 [9·4%] of 2363). There was no evidence that the prevalence of the outcomes differed between trial arms. There was evidence that men, younger individuals, individuals who reported participating in harmful alcohol use, and those who reported internalised stigma were more likely to be non-adherent, and not virally suppressed.

INTERPRETATION

The results assuaged concerns that early ART initiation in a universal testing and treatment setting could lead to reduced adherence and viral suppression.

FUNDING

US National Institute of Allergy and Infectious Diseases (which is a part of the National Institutes of Health), the International Initiative for Impact Evaluation with support from the Bill & Melinda Gates Foundation, US President's Emergency Plan for AIDS Relief, and Medical Research Council UK.

Impact of universal testing and treatment on sexual risk behaviour and herpes simplex virus type 2: a prespecified secondary outcomes analysis of the HPTN 071 (PopART) community-randomised trial

BACKGROUND

Comprehensive HIV prevention strategies have raised concerns that knowledge of interventions to reduce risk of HIV infection might mitigate an individual's perception of risk, resulting in riskier sexual behaviour. We investigated the prespecified secondary outcomes of the HPTN 071 (PopART) trial to determine whether a combination HIV prevention strategy, including universal HIV testing and treatment, changed sexual behaviour; specifically, we investigated whether there was evidence of sexual risk compensation.

METHODS

HPTN 071 (PopART) was a cluster-randomised trial conducted during 2013-18, in which we randomly assigned 21 communities with high HIV prevalence in Zambia and South Africa (total population, approximately 1 million) to combination prevention intervention with universal antiretroviral therapy (ART; arm A), prevention intervention with ART provided according to local guidelines (universal since 2016; arm B), or standard of care (arm C). The trial included a population cohort of approximately 2000 randomly selected adults (aged 18-44 years) in each community (N=38 474 at baseline) who were followed up for 36 months. A prespecified secondary objective was to evaluate the impact of the PopART intervention compared with standard of care on herpes simplex virus type 2 (HSV-2) and sexual behaviour (N=20 422 completed final visit). Secondary endpoints included differences in sexual risk behaviour measures at 36 months and were assessed using a two-stage method for matched cluster-randomised trials. This trial is registered with ClinicalTrials. gov, number NCT01900977.

FINDINGS

The PopART intervention did not substantially change probability of self-reported multiple sex partners, sexual debut, or pregnancy in women at 36 months. Adjusted for baseline community prevalence, reported condomless sex was significantly lower in arm A versus arm C (adjusted prevalence ratio 0·80 [95% CI 0·64-0·99]; p=0·04) but not in arm B versus arm C (0·94 [0·76-1·17]; p=0·55). 3-year HSV-2 incidence was reduced in arm B versus arm C (adjusted risk ratio 0·76 [95% CI 0·63-0·92]; p=0·010); no significant change was shown between arm A versus arm C (0·89 [0·73-1·08]; p=0·199).

INTERPRETATION

We found little evidence of any change in sexual behaviour owing to the PopART interventions, and reassuringly for public health, we saw no evidence of sexual risk compensation. The findings do not help to explain the differences between the two intervention groups of the HPTN 071 (PopART) trial.

FUNDING

National Institute of Allergy and Infectious Diseases, the National Institutes of Health, the International Initiative for Impact Evaluation (3ie), the Bill & Melinda Gates Foundation, the US President's Emergency Plan for AIDS Relief, and the Medical Research Council UK.

Antiretroviral Drug Detection in a Community-Randomized Trial of Universal HIV Testing and Treatment: HPTN 071 (PopART)

Background

Antiretroviral therapy (ART) reduces human immunodeficiency virus (HIV) transmission risk. The primary aim of this study was to evaluate ART uptake in a trial in Zambia and South Africa that implemented a community-wide universal testing and treatment package to reduce HIV incidence.

Methods

Study communities were randomized to 3 arms: A, combination-prevention intervention with universal ART; B, combination-prevention intervention with ART according to local guidelines; and C, standard of care. Samples were collected from people with HIV (PWH) during a survey visit conducted 2 years after study implementation: these samples were tested for 22 antiretroviral (ARV) drugs. Antiretroviral therapy uptake was defined as detection of ≥1 ARV drug. Resistance was evaluated in 612 randomly selected viremic participants. A 2-stage, cluster-based approach was used to assess the impact of the study intervention on ART uptake.

Results

Antiretroviral drugs were detected in 4419 of 6207 (71%) samples (Arm A, 73%; Arm B, 70%; Arm C, 60%); 4140 (94%) of samples with ARV drugs had viral loads <400 copies/mL. Drug resistance was observed in 237 of 612 (39%) viremic participants (95 of 102 [93%] with ARV drugs; 142 of 510 [28%] without drugs). Antiretroviral therapy uptake was associated with older age, female sex, enrollment year, seroconverter status, and self-reported ART (all P < .001). The adjusted risk ratio for ART uptake was similar for Arm A versus C (1.21; 95% confidence interval [CI], .94-1.54; P = .12) and Arm B versus C (1.14; 95% CI, .89-1.46; P = .26).

Conclusions

At the 2-year survey, 71% of PWH were on ART and 94% of those participants were virally suppressed. Universal testing and treatment was not significantly associated with increased ART uptake in this cohort.

Alignment of PrEP adherence with periods of HIV risk among adolescent girls and young women in South Africa and Zimbabwe: a secondary analysis of the HPTN 082 randomised controlled trial

BACKGROUND

Adolescent girls and young women in southern and eastern Africa have adherence challenges with daily oral HIV pre-exposure prophylaxis (PrEP). High adherence is most important during periods of HIV risk (prevention-effective adherence). We aimed to describe HIV risk behaviour and to understand patterns in PrEP adherence during periods of risk among adolescent girls and young women from sub-Saharan Africa.

METHODS

We did a secondary analysis of the HPTN 082 trial, an open-label, interventional, randomised controlled trial of sexually active adolescent girls and young women (aged 16-25 years) testing negative for HIV in Johannesburg and Cape Town, South Africa, and in Harare, Zimbabwe. The primary outcomes were high cumulative PrEP adherence, dichotomised as intracellular tenofovir diphosphate concentrations of at least 700 fmol/punch in dried blood spots at weeks 13, 26, and 52, and high recent PrEP adherence, dichotomised as plasma tenofovir concentrations of at least 40 ng/mL at weeks 13, 26, and 52, among participants who accepted PrEP. We collected data on sexual behaviour every 3 months. We categorised visits into a binary variable of any HIV risk based on condomless sex, more than one sexual partner, primary partner's HIV status and antiretroviral use, transactional sex, drug or alcohol use around sexual activity, and laboratory-diagnosed STIs. We used generalised estimating equations to evaluate associations between HIV risk (reflecting behaviour during the previous 3 months) and high cumulative and recent adherence to PrEP and any PrEP use (quantifiable drug concentrations). The trial is registered with ClinicalTrials.gov, NCT02732730.

FINDINGS

Between Oct 12, 2016, and Oct 25, 2018, 451 women were recruited, and 427 participants (median age 21·0 years [IQR 19·0-22·0]) were eligible for inclusion in this analysis. The proportion of participants reporting at least one HIV risk factor decreased significantly over follow-up, from 364 (85%) participants at enrolment, 226 (60%) at week 13, and 243 (65%) at week 26, to 224 (61%) at week 52 (p<0·0001). Any HIV risk was significantly associated with high PrEP adherence, measured by both tenofovir diphosphate concentrations of at least 700 fmol/punch (adjusted relative risk 1·57 [95% CI 1·09-2·25]; p=0·014) and plasma tenofovir concentrations of at least 40 ng/mL (1·36 [1·11-1·65]; p=0·0025). Any HIV risk was also associated with quantifiable concentrations of tenofovir diphosphate (1·15 [1·03-1·29]; p=0·013) and tenofovir (1·27 [1·09-1·49]; p=0·0022). We observed significant dose-response relationships between number of HIV risk factors and PrEP drug concentrations.

INTERPRETATION

The association between any HIV risk and high PrEP adherence suggests that adolescent girls and young women were able to use PrEP during periods of risk, an indicator of prevention-effective PrEP adherence. Our findings support a shift in the PrEP framework to acknowledge prevention-effective adherence practices, which might improve PrEP delivery and adherence support for adolescent girls and young women in HIV-endemic settings.

FUNDING

US National Institutes of Health.

How Can Progress Toward Ending the Human Immunodeficiency Virus Epidemic in the United States Be Monitored?

The plan for Ending the HIV (human immunodeficiency virus) Epidemic (EHE) in the United States aims to reduce new infections by 75% by 2025 and by 90% by 2030. For EHE to be successful, it is important to accurately measure changes in numbers of new HIV infections after 5 and 10 years (to determine whether the EHE goals have been achieved) but also over shorter timescales (to monitor progress and intensify prevention efforts if required). In this viewpoint, we aim to demonstrate why the method used to monitor progress toward the EHE goals must be carefully considered. We briefly describe and discuss different methods to estimate numbers of new HIV infections based on longitudinal cohort studies, cross-sectional incidence surveys, and routine surveillance data. We particularly focus on identifying conditions under which unadjusted and adjusted estimates based on routine surveillance data can be used to estimate changes in new HIV infections.

HIV drug resistance in a community-randomized trial of universal testing and treatment: HPTN 071 (PopART)

INTRODUCTION

Universal HIV testing and treatment (UTT) has individual and public health benefits. HPTN 071 (PopART), a community-randomized trial in Zambia and South Africa, demonstrated that UTT decreased HIV incidence. This endpoint was assessed in a cohort of >48,000 randomly selected adults in the study communities. We evaluated the impact of UTT on HIV drug resistance in this cohort and compared other resistance-related outcomes in participants with recent versus non-recent HIV infection.

METHODS

Two years after the start of HPTN 071 (2016-2017), 6259 participants were HIV positive and 1902 were viremic (viral load >400 copies/ml). HIV genotyping and antiretroviral (ARV) drug testing were performed for viremic participants in three groups: seroconverters (infected <1 year), non-seroconverters (infected >1 year, random subset) and participants with unknown duration of infection (random subset). A two-stage cluster-based approach was used to assess the impact of the study intervention on drug resistance. Treatment failure was defined as being viremic with ARV drugs detected. Participants were classified as ARV naïve based on self-report and ARV drug testing.

RESULTS

Genotyping results were obtained for 758 participants (143 seroconverters; 534 non-seroconverters; and 81 unknown duration of infection). The estimated prevalence of resistance in the study communities was 37% for all viremic persons and 11% for all HIV-positive persons. There was no association between UTT and drug resistance. Resistance was detected in 14.0% of seroconverters and 40.8% of non-seroconverters (non-nucleoside reverse transcriptase inhibitor resistance: 14.0% and 39.9%; nucleoside/nucleotide reverse transcriptase inhibitor resistance: 0.7% and 15.5%; protease inhibitor resistance: 0% and 1.9%; multi-class resistance: 0.7% and 16.1%, respectively). ARV drugs were detected in 2/139 (1.4%) of seroconverters and 94/534 (17.6%) of non-seroconverters tested. These participants were classified as failing ART; 88 (93.6%) of the non-seroconverters failing ART had resistance. Mutations used for surveillance of transmitted drug resistance were detected in 10.5% of seroconverters and 15.1% of non-seroconverters who were ARV naive.

CONCLUSIONS

UTT was not associated with an increase in drug resistance in this cohort. Higher rates of drug resistance and multi-class resistance were observed in non-seroconverters compared to seroconverters.

The association between HIV stigma and HIV incidence in the context of universal testing and treatment: analysis of data from the HPTN 071 (PopART) trial in Zambia and South Africa

INTRODUCTION

To investigate the association between individual and community-level measures of HIV stigma and HIV incidence within the 21 communities participating in the HPTN (071) PopART trial in Zambia and South Africa.

METHODS

Secondary analysis of data from a population-based cohort followed-up over 36 months between 2013 and 2018. The outcome was rate of incident HIV infection among individuals who were HIV negative at cohort entry. Individual-level exposures, measured in a random sample of all participants, were: (1) perception of stigma in the community, (2) perception of stigma in health settings and (3) fear and judgement towards people living with HIV. Individual-level analyses were conducted with adjusted, individual-level Poisson regression. Community-level HIV stigma exposures drew on data reported by people living with HIV, health workers and community members. We used linear regression to explore the association between HIV stigma and community-level HIV incidence.

RESULTS

Among 8172 individuals who were HIV negative and answered individual-level stigma questions at enrolment to the cohort, there was no evidence of a statistically significant association between any domain of HIV stigma and risk of incident HIV infection. Among the full cohort of 26,110 individuals among whom HIV incidence was measured, there was no evidence that community-level HIV incidence was associated with any domain of HIV stigma.

CONCLUSIONS

HIV stigma is often cited as a barrier to the effectiveness of HIV prevention programming. However, in the setting for the HPTN 071 "PopART trial," measured stigma alone was not associated with the risk of HIV infection.

PrEP use and HIV seroconversion rates in adolescent girls and young women from Kenya and South Africa: the POWER demonstration project

INTRODUCTION

HIV incidence remains high among African adolescent girls and young women (AGYW). The primary objective of this study is to assess pre-exposure prophylaxis (PrEP) initiation, use, persistence and HIV acquisition among African AGYW offered PrEP in order to inform PrEP scale-up.

METHODS

POWER was a prospective implementation science evaluation of PrEP delivery for sexually active HIV-negative AGYW ages 16-25 in family planning clinics in Kisumu, Kenya and youth and primary healthcare clinics in Cape Town and Johannesburg, South Africa. Follow-up visits occurred at month 1 and quarterly for up to 36 months. PrEP users were defined based on the month 1 refill. PrEP persistence through month 6 was assessed using Kaplan-Meier survival analysis among AGYW with a month 1 visit, defining non-persistence as an ≥15 day gap in PrEP availability for daily dosing. PrEP execution was evaluated in a subset with PrEP supply from the prior visit sufficient for daily dosing by measuring blood tenofovir diphosphate (TFV-DP) levels.

RESULTS

From June 2017 to September 2020, 2550 AGYW were enrolled (1000 in Kisumu, 787 in Cape Town and 763 in Johannesburg). Median age was 21 years, 66% had a sexual partner of unknown HIV status, and 29% had chlamydia and 10% gonorrhoea. Overall, 2397 (94%) initiated PrEP and 749 (31%) had a refill at 1 month. Of AGYW who could reach 6 months of post-PrEP initiation follow-up, 128/646 (20%) persisted with PrEP for 6 months and an additional 92/646 (14%) had a gap and restarted PrEP. TFV-DP levels indicated that 47% (91/193) took an average of ≥4 doses/week. Sixteen HIV seroconversions were observed (incidence 2.2 per 100 person-years, 95% CI 1.2, 3.5); 13 (81%) seroconverters either did not have PrEP dispensed in the study interval prior to seroconversion or TFV-DP levels indicated <4 doses/week in the prior 6 weeks.

CONCLUSIONS

In this study of PrEP integration with primary care and reproductive health services for African AGYW, demand for PrEP was high. Although PrEP use decreased in the first months, an important fraction used PrEP through 6 months.  Strategies are needed to simplify PrEP delivery, support adherence and offer long-acting PrEP options to improve persistence and HIV protection.

Doxycycline post-exposure prophylaxis for prevention of sexually transmitted infections among Kenyan women using HIV pre-exposure prophylaxis: study protocol for an open-label randomized trial

BACKGROUND

Women in Africa face disproportionate risk of human immunodeficiency virus (HIV) acquisition, accounting for more than half of new infections in Africa and similarly face a disproportionate burden of sexually transmitted infections (STIs). Very high STI prevalence is being observed globally, especially among people taking pre-exposure prophylaxis (PrEP) for HIV prevention. Doxycycline post-exposure prophylaxis (dPEP) has been proposed as an STI prevention strategy to reduce chlamydia, syphilis, and possibly gonorrhea, and trials are ongoing among cisgender men who have sex with men (MSM) and transgender women who are taking PrEP in high-income settings. We designed and describe here the first open-label trial to determine the effectiveness of dPEP to reduce STI incidence among cisgender women.

METHODS

We are conducting an open-label 1:1 randomized trial of dPEP versus standard of care (STI screening and treatment and risk-reduction counseling without dPEP) among 446 Kenyan women aged ≥ 18 and ≤ 30 years old women taking PrEP. Women are followed for 12 months, with quarterly STI testing, treatment, and adherence counseling. The primary trial outcome will be the combined incidence of Chlamydia trachomatis, Neisseria gonorrhoeae, and Treponema pallidum, compared between the randomized groups. We will also assess dPEP acceptability, tolerability, safety, impact on sexual behavior, adherence, and occurrence of antimicrobial resistance (AMR) in N. gonorrhoeae and C. trachomatis isolates. Finally, we will estimate cost per incident STI case and complications averted accounting for nonadherence and benefits relative AMR or side effects.

DISCUSSION

The results of this trial may have immediate implications for the global epidemic of STIs and sexual health. If effective, dPEP could put STI prevention into women's hands. While dPEP may be able to prevent STIs, it carries important risks that could counter its benefits; global debate about the balance of these potential risks and benefits requires data to inform policy and implementation and our study aims to fill this gap.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04050540 .

High HIV incidence among young women in South Africa: Data from a large prospective study

Introduction

South Africa has the highest national burden of HIV globally. Understanding drivers of HIV acquisition in recently completed, prospective studies in which HIV was an endpoint may help inform the strategy and investments in national HIV prevention efforts and guide the design of future HIV prevention trials. We assessed HIV incidence and correlates of incidence among women enrolled in ECHO (Evidence for Contraceptive Options and HIV Outcomes), a large, open-label randomized clinical trial that compared three highly effective. reversible methods of contraception and rates of HIV acquisition.

Methods

During December 2015 to October 2018, ECHO followed sexually active, HIV-seronegative women, aged 16–35 years, seeking contraceptive services and willing to be randomized to one of three contraceptive methods (intramuscular depot medroxyprogesterone acetate, copper intrauterine device, or levonorgestrel implant) for 12–18 months at nine sites in South Africa. HIV incidence based on prospectively observed HIV seroconversion events. Cox proportional hazards regression models were used to define baseline cofactors related to incident HIV infection.

Results

5768 women were enrolled and contributed 7647 woman-years of follow-up. The median age was 23 years and 62.5% were ≤24 years. A total of 345 incident HIV infections occurred, an incidence of 4.51 per 100 woman-years (95%CI 4.05–5.01). Incidence was >3 per 100 woman-years at all sites. Age ≤24 years, baseline infection with sexually transmitted infections, BMI≤30, and having new or multiple partners in the three months prior to enrollment were associated with incident HIV.

Conclusions

HIV incidence was high among South African women seeking contraceptive services. Integration of diagnostic management of sexually transmitted infections alongside delivery of HIV prevention options in health facilities providing contraception services are needed to mitigate ongoing risks of HIV acquisition for this vulnerable population.

Clinical trial registration

ClinicalTrials.gov, number NCT02550067 was the main Clinical Trial from which this secondary, non-randomized / observational analysis was derived with data limited to just South African sites.

Efficacy of single-dose HPV vaccination among young African women

Background

Single-dose HPV vaccination, if efficacious, would be tremendously advantageous; simplifying implementation and decreasing costs.

Methods

We performed a randomized, multi-center, double-blind, controlled trial of single-dose nonavalent (HPV 16/18/31/33/45/52/58/6/11) or bivalent (HPV 16/18) HPV vaccination compared to meningococcal vaccination among Kenyan women aged 15-20 years. Enrollment and six monthly cervical swabs and a month three vaginal swab were tested for HPV DNA. Enrollment sera were tested for HPV antibodies. The modified intent-to-treat (mITT) cohort comprised participants who tested HPV antibody negative at enrollment and HPV DNA negative at enrollment and month three. The primary outcome was incident persistent vaccine-type HPV infection by month 18.

Results

Between December 2018 and June 2021, 2,275 women were randomly assigned and followed; 758 received the nonavalent HPV vaccine, 760 the bivalent HPV vaccine, and 757 the meningococcal vaccine; retention was 98%. Thirty-eight incident persistent infections were detected in the HPV 16/18 mITT cohort: one each among participants assigned to the bivalent and nonavalent groups and 36 among those assigned to the meningococcal group; nonavalent Vaccine Efficacy (VE) was 97.5% (95%CI 81.7-99.7%, p=<0.0001), and bivalent VE was 97.5% (95%CI 81.6-99.7%, p=<0.0001). Thirty-three incident persistent infections were detected in the HPV 16/18/31/33/45/52/58 mITT cohort: four in the nonavalent group and 29 in the meningococcal group; nonavalent VE for HPV 16/18/31/33/45/52/58 was 88.9% (95%CI 68.5-96.1%, p<0.0001). The rate of SAEs was 4.5-5.2% by group.

Conclusions

Over the 18 month time-frame we studied, single-dose bivalent and nonavalent HPV vaccines were each highly effective in preventing incident persistent oncogenic HPV infection, similar to multidose regimens.

Adaptive HIV pre-exposure prophylaxis adherence interventions for young South African women: Study protocol for a sequential multiple assignment randomized trial

INTRODUCTION

Pre-exposure prophylaxis (PrEP) is a highly effective HIV prevention strategy and is recommended for populations at risk of HIV, including adolescent girls and young women (AGYW) in HIV endemic settings. However, PrEP continuation and high adherence remain challenges to its impact. Existing PrEP adherence interventions can be time- and cost-intensive. Widescale PrEP delivery will require the identification of layered PrEP support strategies for AGYW with diverse prevention needs. We describe the design of a sequential multiple assignment randomized trial (SMART) to evaluate a PrEP adherence support model using scalable, stepped interventions in AGYW in South Africa.

METHODS

"PrEP SMART" is a randomized trial in Johannesburg, South Africa, enrolling AGYW who are between 18 and 25 years of age, sexually active, newly initiating PrEP, and have regular access to a mobile phone. Participants are randomized 1:1 to standard-of-care PrEP counseling with either two-way SMS or WhatsApp group adherence support. Adherence is assessed at three months using tenofovir diphosphate (TFV-DP) levels from dried blood spots collected at month 2 to categorize participants as "responders" (TFV-DP ≥500 fmol/punch) or "non-responders" (TFV-DP <500 fmol/punch). AGYW defined as 'non-responders' undergo a secondary 1:1 randomization to either quarterly drug-level feedback counseling or monthly issue-focused counseling, in addition to their first-level intervention. The primary outcome is PrEP adherence at nine months (TFV-DP ≥700 fmol/punch). We will assess the effect of our two initial interventions on TFV-DP levels among responders, assess the effect of our intensified interventions on TFV-DP levels among non-responders, and identify the optimal sequence of adherence interventions through nine months.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04038060. Registered on 30 July 2019.

Practical issues in operationalizing the design and outcome evaluation of cluster randomized trials

Trial designs using cluster-level randomization are necessary when interventions have intended effects that cannot be measured with individual randomization. When an intervention is intrinsically only able to be delivered to a cluster or when implementation of an individual level intervention is only feasibly implemented at a cluster level, cluster-level randomization is required. In designing the strategy for evaluation of the primary outcome of a cluster randomized trial, there are a multitude of important decisions to consider. While these decisions are guided primarily by the intervention-who benefits, what is the intended effect and when will it be achieved-there are important detailed choices that affect potential bias and statistical power, and implementation considerations that require compromise for considerations of feasibility and practicality. Through the lens of three large completed cluster randomized trials in HIV prevention, we present specific choices made for the overall evaluation plan, together with some of the detailed considerations, compromises and modifications that occurred during trial implementation.

Evaluation of multi-assay algorithms for identifying individuals with recent HIV infection: HPTN 071 (PopART)

Background

Assays and multi-assay algorithms (MAAs) have been developed for population-level cross-sectional HIV incidence estimation. These algorithms use a combination of serologic and/or non-serologic biomarkers to assess the duration of infection. We evaluated the performance of four MAAs for individual-level recency assessments.

Methods

Samples were obtained from 220 seroconverters (infected <1 year) and 4,396 non-seroconverters (infected >1 year) enrolled in an HIV prevention trial (HPTN 071 [PopART]); 28.6% of the seroconverters and 73.4% of the non-seroconverters had HIV viral loads ≤400 copies/mL. Samples were tested with two laboratory-based assays (LAg-Avidity, JHU BioRad-Avidity) and a point-of-care assay (rapid LAg). The four MAAs included different combinations of these assays and HIV viral load. Seroconverters on antiretroviral treatment (ART) were identified using a qualitative multi-drug assay.

Results

The MAAs identified between 54 and 100 (25% to 46%) of the seroconverters as recently-infected. The false recent rate of the MAAs for infections >2 years duration ranged from 0.2%-1.3%. The MAAs classified different overlapping groups of individuals as recent vs. non-recent. Only 32 (15%) of the 220 seroconverters were classified as recent by all four MAAs. Viral suppression impacted the performance of the two LAg-based assays. LAg-Avidity assay values were also lower for seroconverters who were virally suppressed on ART compared to those with natural viral suppression.

Conclusions

The four MAAs evaluated varied in sensitivity and specificity for identifying persons infected <1 year as recently infected and classified different groups of seroconverters as recently infected. Sensitivity was low for all four MAAs. These performance issues should be considered if these methods are used for individual-level recency assessments.

Association between rectal gonorrhoea and HIV incidence in men who have sex with men: a meta-analysis

BACKGROUND

Incidence of rectal gonorrhoea (GC) has been hypothesised as a correlate of HIV exposure in prevention trials of men who have sex with men (MSM). High rectal GC incidence in MSM trials of new biomedical prevention drugs may provide supportive evidence for ongoing HIV risk. Empirical evidence of correlation between rectal GC and HIV incidence is needed to assess whether high rectal GC rates reliably correlate with high risk of HIV.

METHODS

Rectal GC and HIV are routinely tested in sexual health clinics (SHCs) throughout England. Through routine surveillance data collected at visits to SHCs, we assessed HIV incidence and new rectal GC diagnoses in repeat visits by HIV-negative MSM between 2011 and 2018, predating widespread roll-out of pre-exposure prophylaxis. Meta-analysis regression assessed population-level association between HIV and rectal GC incidence over time.

FINDINGS

Between 2011 and 2018, HIV and rectal GC incidence was assessed in 541 056 HIV-negative MSM attending SHCs in England. HIV incidence among MSM attending SHCs fell from 1.26/100 person-years (PYs) in 2011 to 0.28/100 PYs in 2018. Rectal GC rates increased from 3.5/100 PYs to 11.1/100 PYs over the same period. The rate of HIV incidence decreased by 22.3% for each percent increase in rectal GC (95% CI -30.8 to -14.7, p<0.001).

INTERPRETATION

Among the population of MSM attending SHCs in England, rectal GC rates increased substantially while HIV incidence rates decreased between 2011 and 2018. HIV incidence likely decreased through expanded HIV testing, prompt antiretroviral treatment (ART) initiation and increased viral suppression in persons living with HIV, interventions that did not decrease rectal GC. Rectal GC may not be an ideal proxy for HIV incidence in trials, as HIV exposure risk is complex and context dependent, given effective HIV prevention interventions in MSM.

INTRODUCTION

Incidence of Herpes Simplex Virus Type 2 Infection Among African Women Using Depot Medroxyprogesterone Acetate, a Copper Intrauterine Device, or a Levonorgestrel Implant for Contraception: A Nested Randomized Trial

BACKGROUND

Globally, women have higher herpes simplex virus type 2 (HSV-2) prevalence than men; data from observational studies suggest a possible association of HSV-2 acquisition with use of intramuscular depot medroxyprogesterone acetate (DMPA-IM).

METHODS

Within a randomized trial of the effect of 3 contraceptive methods-DMPA-IM, a copper intrauterine device (IUD), and a levonorgestrel (LNG) implant-on human immunodeficiency virus (HIV) acquisition, we assessed HSV-2 acquisition. HSV-2 and HIV seronegative women, aged 16-35 years, and seeking effective contraception were followed for 12-18 months at 12 sites in Eswatini, Kenya, South Africa, and Zambia from 2015 to 2018. HSV-2 serologic testing was done at enrollment and final study visits. Intention-to-treat analysis using Poisson regression with robust standard errors compared HSV-2 incidence by contraceptive method.

RESULTS

At baseline, 4062 randomized women were HSV-2 seronegative, of whom 3898 (96.0%) had a conclusive HSV-2 result at their final study visit. Of these, 614 (15.8%) acquired HSV-2, at an incidence of 12.4/100 person-years (p-y): 10.9/100 p-y among women assigned DMPA-IM, 13.7/100 p-y the copper IUD, and 12.7/100 p-y the LNG implant. Incidence rate ratios (IRR) for HSV-2 acquisition were 0.80 (95% confidence interval [CI], .65-.97) for DMPA-IM compared with copper IUD, 0.86 (95% CI, .71-1.05) for DMPA-IM compared with LNG implant, and 1.08 (95% CI, .89-1.30) for copper IUD compared with LNG implant. HSV-2 acquisition risk was significantly increased among women who also acquired HIV during follow-up (IRR 3.55; 95% CI, 2.78-4.48).

CONCLUSIONS

In a randomized trial, we found no association between HSV-2 acquisition and use of 3 contraceptive methods.

TRIAL REGISTRATION

ClinicalTrials.gov number NCT02550067.

Validation of population-level HIV-1 incidence estimation by cross-sectional incidence assays in the HPTN 071 (PopART) trial

Introduction

Cross‐sectional incidence testing is used to estimate population‐level HIV incidence and measure the impact of prevention interventions. There are limited data evaluating the accuracy of estimates in settings where antiretroviral therapy coverage and levels of viral suppression are high. Understanding cross‐sectional incidence estimates in these settings is important as viral suppression can lead to false recent test results. We compared the accuracy of multi‐assay algorithms (MAA) for incidence estimation to that observed in the community‐randomized HPTN 071 (PopART) trial, where the majority of participants with HIV infection were virally suppressed.

Methods

HIV incidence was assessed during the second year of the study, and included only individuals who were tested for HIV at visits 1 and 2 years after the start of the study (2016–2017). Incidence estimates from three MAAs were compared to the observed incidence between years 1 and 2 (MAA‐C: LAg‐Avidity <2.8 ODn + BioRad Avidity Index <95% + VL >400 copies/ml; LAg+VL MAA: LAg‐Avidity <1.5 ODn + VL >1000 copies/ml; Rapid+VL MAA: Asanté recent rapid result + VL >1000 copies/ml). The mean duration of recent infection (MDRI) used for the three MAAs was 248, 130 and 180 days, respectively.

Results and discussion

The study consisted of: 15,845 HIV‐negative individuals; 4406 HIV positive at both visits; and 221 who seroconverted between visits. Viral load (VL) data were available for all HIV‐positive participants at the 2‐year visit. Sixty four (29%) of the seroconverters and 3227 (72%) prevelant positive participants were virally supressed (<400 copies/ml). Observed HIV incidence was 1.34% (95% CI: 1.17–1.53). Estimates of incidence were similar to observed incidence for MAA‐C, 1.26% (95% CI: 1.02–1.51) and the LAg+VL MAA, 1.29 (95% CI: 0.97–1.62). Incidence estimated by the Rapid+VL MAA was significantly lower than observed incidence (0.92%, 95% CI: 0.69–1.15, p<0.01).

Conclusions

MAA‐C and the LAg+VL MAA provided accurate point estimates of incidence in this cohort with high levels of viral suppression. The Rapid+VL significantly underestimated incidence, suggesting that the MDRI recommended by the manufacturer is too long or the assay is not accurately detecting enough recent infections.

Integration of pre-exposure prophylaxis services into public HIV care clinics in Kenya: a pragmatic stepped-wedge randomised trial

BACKGROUND

Successful and sustainable models for HIV pre-exposure prophylaxis (PrEP) delivery in public health systems in Africa are needed. We aimed to evaluate the implementation of PrEP delivery integrated in public HIV care clinics in Kenya.

METHODS

As part of Kenya's national PrEP roll-out, we conducted a stepped-wedge cluster-randomised pragmatic trial to catalyse scale-up of PrEP delivery integrated in 25 public HIV care clinics. We selected high-volume clinics in these regions (ie, those with a high number of people living with HIV enrolled in HIV care and treatment). Clinics (each representing a cluster) were stratified by region and randomly assigned to the order in which clinic staff would receive PrEP training and ongoing technical support using numbered opaque balls picked from a bag. There was no masking. PrEP provision was done by clinic staff without additional financial support. Data were abstracted from records of individuals initiating PrEP. The primary outcome was the number of people initiating PrEP per clinic per month comparing intervention to control periods. Other outcomes included PrEP continuation, adherence, and incident HIV infections. This trial is registered with ClinicalTrials.gov, NCT03052010.

FINDINGS

After the baseline period, which started in January, 2017, every month two to six HIV care clinics crossed over from control to intervention, until August, 2017, when all clinics were implementing the intervention. Of 4898 individuals initiating PrEP (27 during the control period and 4871 during the intervention period), 2640 (54%) were women, the median age was 31 years (IQR 25-39), and 4092 (84%) reported having a partner living with HIV. The mean monthly number of PrEP initiations per clinic was 0·1 (SD 0·5) before the intervention and 7·5 (2·7) after intervention introduction (rate ratio 23·7, 95% CI 14·2-39·5, p<0·0001). PrEP continuation was 57% at 1 month, 44% at 3 months, and 34% at 6 months, and 12% of those who missed a refill returned later for PrEP re-initiation. Tenofovir diphosphate was detected in 68 (96%) of 71 blood samples collected from a randomly selected subset of participants. Six HIV infections were observed over 2531 person-years of observation (incidence 0·24 cases per 100 person-years), three of which occurred at the first visit after PrEP initiation.

INTERPRETATION

We observed high uptake, reasonable continuation with high adherence, frequent PrEP restarts, and low HIV incidence. Integration of PrEP services within public HIV care clinics in Africa is feasible.

FUNDING

National Institute of Mental Health and Bill & Melinda Gates Foundation.

Single-dose HPV vaccination efficacy among adolescent girls and young women in Kenya (the KEN SHE Study): study protocol for a randomized controlled trial

BACKGROUND

HPV infection is the primary cause of cervical cancer, a leading cause of cancer among women in Kenya and many sub-Saharan African countries. High coverage of HPV vaccination is a World Health Organization priority to eliminate cervical cancer globally, but vaccine supply and logistics limit widespread implementation of the current two or three dose HPV vaccine schedule.

METHODS

We are conducting an individual randomized controlled trial to evaluate whether a single dose of the bivalent (HPV 16/18) or nonavalent (HPV 16/18/31/33/45/52/58/6/11) HPV vaccine prevents persistent HPV infection, a surrogate marker for precancerous lesions and cervical cancer. The primary objective is to compare the efficacy of immediate, single-dose bivalent or nonavalent vaccination with delayed HPV vaccination. Kenyan women age 15-20 years old are randomized to immediate bivalent HPV and delayed meningococcal vaccine (group 1), immediate nonavalent HPV vaccine and delayed meningococcal vaccine (group 2), or immediate meningococcal vaccine and delayed HPV vaccine (group 3) with 36 months of follow-up. The primary outcome is persistent vaccine-type HPV infection by month 18 and by month 36 for the final durability outcome. The secondary objectives include to (1) evaluate non-inferiority of antibody titers among girls and adolescents (age 9 to 14 years) from another Tanzanian study, the DoRIS Study (NCT02834637), compared to KEN SHE Study participants; (2) assess the memory B cell immune response at months 36 and 37; and (3) estimate cost-effectiveness using the trial results and health economic models.

DISCUSSION

This study will evaluate single-dose HPV vaccine efficacy in Africa and has the potential to guide public health policy and increase HPV vaccine coverage. The secondary aims will assess generalizability of the trial results by evaluating immunobridging from younger ages, durability of the immune response, and the long-term health benefits and cost of single-dose HPV vaccine delivery.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03675256 . Registered on September 18, 2018.

PopART-IBM, a highly efficient stochastic individual-based simulation model of generalised HIV epidemics developed in the context of the HPTN 071 (PopART) trial

Mathematical models are powerful tools in HIV epidemiology, producing quantitative projections of key indicators such as HIV incidence and prevalence. In order to improve the accuracy of predictions, such models need to incorporate a number of behavioural and biological heterogeneities, especially those related to the sexual network within which HIV transmission occurs. An individual-based model, which explicitly models sexual partnerships, is thus often the most natural type of model to choose. In this paper we present PopART-IBM, a computationally efficient individual-based model capable of simulating 50 years of an HIV epidemic in a large, high-prevalence community in under a minute. We show how the model calibrates within a Bayesian inference framework to detailed age- and sex-stratified data from multiple sources on HIV prevalence, awareness of HIV status, ART status, and viral suppression for an HPTN 071 (PopART) study community in Zambia, and present future projections of HIV prevalence and incidence for this community in the absence of trial intervention.

In this paper we present PopART-IBM, an individual-based model used to simulate HIV transmission in communities in high prevalence settings. We show that PopART-IBM can simulate transmission over a span of decades in a large community in less than a minute. This computational efficiency allows us to calibrate the model within an inference framework, and we show an illustrative example of calibration using an adaptive population Monte Carlo Approximate Bayesian Computation algorithm for a community in Zambia that was part of the HPTN-071 (PopART) trial. We compare the detailed model output to real-world data collected during the trial from this community. Finally, we project how the HIV epidemic would have changed over time in this community if no intervention from the trial had occurred.

Cabotegravir for HIV Prevention in Cisgender Men and Transgender Women

BACKGROUND

Safe and effective long-acting injectable agents for preexposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) infection are needed to increase the options for preventing HIV infection.

METHODS

We conducted a randomized, double-blind, double-dummy, noninferiority trial to compare long-acting injectable cabotegravir (CAB-LA, an integrase strand-transfer inhibitor [INSTI]) at a dose of 600 mg, given intramuscularly every 8 weeks, with daily oral tenofovir disoproxil fumarate-emtricitabine (TDF-FTC) for the prevention of HIV infection in at-risk cisgender men who have sex with men (MSM) and in at-risk transgender women who have sex with men. Participants were randomly assigned (1:1) to receive one of the two regimens and were followed for 153 weeks. HIV testing and safety evaluations were performed. The primary end point was incident HIV infection.

RESULTS

The intention-to-treat population included 4566 participants who underwent randomization; 570 (12.5%) identified as transgender women, and the median age was 26 years (interquartile range, 22 to 32). The trial was stopped early for efficacy on review of the results of the first preplanned interim end-point analysis. Among 1698 participants from the United States, 845 (49.8%) identified as Black. Incident HIV infection occurred in 52 participants: 13 in the cabotegravir group (incidence, 0.41 per 100 person-years) and 39 in the TDF-FTC group (incidence, 1.22 per 100 person-years) (hazard ratio, 0.34; 95% confidence interval, 0.18 to 0.62). The effect was consistent across prespecified subgroups. Injection-site reactions were reported in 81.4% of the participants in the cabotegravir group and in 31.3% of those in the TDF-FTC group. In the participants in whom HIV infection was diagnosed after exposure to CAB-LA, INSTI resistance and delays in the detection of HIV infection were noted. No safety concerns were identified.

CONCLUSIONS

CAB-LA was superior to daily oral TDF-FTC in preventing HIV infection among MSM and transgender women. Strategies are needed to prevent INSTI resistance in cases of CAB-LA PrEP failure. (Funded by the National Institute of Allergy and Infectious Diseases and others; HPTN 083 ClinicalTrials.gov number, NCT02720094.).

Incorporating oral PrEP into standard prevention services for South African women: a nested interrupted time-series study

BACKGROUND

As oral pre-exposure prophylaxis (PrEP) becomes the standard of prevention globally, its potential effect on HIV incidence in clinical trials of new prevention interventions is unknown, particularly for trials among women. In a trial measuring HIV incidence in African women, oral PrEP was incorporated into the standard of prevention in the trial's last year. We assessed the effect of on-site access to PrEP on HIV incidence in this natural experiment.

METHODS

We did a nested interrupted time-series study using data from the ECHO trial. At 12 sites in four countries (Eswatini, Kenya, South Africa, and Zambia), women (aged 16-35 years) were randomly assigned to receive one of three contraceptives between Dec 14, 2015, and Sept 12, 2017, and followed up quarterly for up to 18 months to determine the effect of contraceptive method on HIV acquisition. Women were eligible if they wanted long-acting contraception, were medically qualified to receive study contraceptives, and had not used any of the study contraceptives in the past 6 months. The present analyses are limited to nine South African sites where on-site access to oral PrEP was implemented between March 13 and June 12, 2018. Using an interrupted time-series design, we compared HIV incidence before versus after PrEP access, limited to quarterly study visits at which on-site PrEP access was available to at least some participants and, in a sensitivity analysis, to the 180 days before and after access. The outcome was incident HIV infection, detected using two rapid HIV tests done in parallel for each participant at every scheduled follow-up visit. This study is registered on ClinicalTrials.gov, NCT02550067.

FINDINGS

2124 women were followed up after on-site PrEP access began, of whom 543 (26%) reported PrEP use. A total of 12 HIV seroconversions were observed in 556 person-years (incidence 2·16%) after on-site PrEP access, compared with 133 HIV seroconversions in 2860 person-years (4·65%) before PrEP access (adjusted incidence rate ratio [IRR] 0·45, 95% CI 0·25-0·82, p=0·0085). Similar results were also observed when limiting the analysis to 180 days before versus after PrEP access. A total of 46 HIV seroconversions were observed in 919 person-years within 180 days before PrEP access, compared with 11 seroconversions in 481 person-years in the 180 days following PrEP access (incidence 5·00 vs 2·29 per 100 person-years; IRR 0·43, 95% CI 0·22-0·88, p=0·012).

INTERPRETATION

On-site access to PrEP as part of standard of prevention in a clinical trial among women in South Africa was associated with halving HIV incidence, when approximately a quarter of women started PrEP. Providing access to on-site PrEP could decrease incidence in HIV prevention trials. These data are also among the first to show in any setting that access to PrEP is associated with decreased HIV acquisition among South African women.

FUNDING

Bill & Melinda Gates Foundation, United States Agency for International Development, President's Emergency Plan for AIDS Relief, the Swedish International Development Cooperation Agency, South African Medical Research Council, and United Nations Population Fund.