Large connected components in sexual networks and their role in HIV transmission in Sub-Saharan Africa: A model-based analysis of HPTN 071(PopART) data.

The HIV epidemic in sub-Saharan Africa is historically characterised by high levels of prevalence and incidence. With the global effort to reach UNAIDS 95-95-95 targets, the scaling-up of HIV treatment, and focused preventive interventions, incidence has been declining over the past decade, albeit non-consistently across different sex and age groups. Two questions remain to be addressed to help tailor setting-specific interventions and allocate resources optimally.

Estimated impact of long-acting injectable PrEP in South Africa: a model comparison analysis.

Introduction: Long-acting injectable cabotegravir (CAB-LA) demonstrated superiority to daily tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) for human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) in two clinical trials. This analysis projects the impact of expanding PrEP coverage with CAB-LA in South Africa between 2022 and 2042.

Methods: Three independently calibrated models of HIV transmission in South Africa (Synthesis, EMOD-HIV, Thembisa) projected HIV acquisitions and effective coverage (average PrEP coverage across exposure groups, weighted by HIV incidence in the absence of PrEP in each group) over 20 years under multiple scenarios of PrEP expansion compared to no PrEP expansion.

The science at HIVR4P 2024: The era of choice in biomedical HIV prevention.

Introduction: HIVR4P 2024, the 5th HIV Research for Prevention Conference, took place in Lima, Peru, 6-10 October 2024. The conference focused on new developments in HIV prevention from basic research to new product development and implementation science.

Methods: Sessions were assigned to one of five tracks: basic science; pre-exposure prophylaxis (PrEP) and antiretroviral (ARV)-based prevention; vaccines and broadly neutralizing antibodies (bNAbs); applied and implementation science; and other prevention modalities and cross-cutting issues.

Research designs to generate evidence of HIV post-exposure prophylaxis effectiveness for new long-acting agents.

Introduction: New longer-acting antiretroviral (ARV) drugs-that is single doses with antiviral activity for at least a month-are being utilized for HIV treatment and pre-exposure prophylaxis (PrEP) but have not been explored for post-exposure prophylaxis (PEP). A "one-and-done" simplification of PEP has the potential to serve the HIV prevention needs of individuals not being met with traditional services and expand overall biomedical HIV prevention coverage. We discuss challenges with the assessment of PEP effectiveness in human trials and potential study designs that could generate evidence needed to inform the use of new, single-administered, long-acting ARVs for PEP.

Fixed dosing versus weight-based dosing of HIV-1 prophylactic monoclonal antibodies in adults: a post-hoc, cross-protocol pharmacokinetics modelling study.

Background: Pharmacokinetic (PK) modelling and simulations have been used to support label changes of dosing levels or strategies for multiple marketed therapeutic monoclonal antibodies (mAbs). Using data from early-phase clinical trials in adults without HIV-1, we compared fixed and weight-based dosing strategies for three HIV-1 broadly neutralising mAbs planned for prevention efficacy evaluation: PGDM1400LS, PGT121.414.

Doxycycline to prevent bacterial sexually transmitted infections in the USA: final results from the DoxyPEP multicentre, open-label, randomised controlled trial and open-label extension.

Background: Doxycycline post-exposure prophylaxis (doxy-PEP) is a promising intervention to reduce bacterial sexually transmitted infections (STIs). We evaluated the effect of doxy-PEP on STI incidence and antimicrobial resistance in men who have sex with men and transgender women for up to 12 months of follow-up, inlcuding an open-label extension.

Methods: DoxyPEP, an open-label trial in Seattle (WA, USA) and San Francisco (CA, USA) among men who have sex with men and transgender women with at least one bacterial STI in the past year, randomly assigned participants by clinic (with computer-generated variable block sizes) 2:1 to doxy-PEP (200 mg doxycycline delayed-release tablets 24-72 h after condomless sex) or standard care.

Impact of male peer-led outreach on uptake of HIV testing among male partners of pregnant women in Uganda: a randomized trial.

Introduction: Male partner HIV testing and engagement in antenatal care (ANC) is associated with improved clinical outcomes for men, pregnant women and infants. However, testing rates remain low among male partners of pregnant women receiving ANC in Africa. We evaluated the impact of male peer outreach to increase HIV testing among partners of pregnant women in Uganda.

A survey weighted analysis of HPTN 071 (PopART) primary outcome of HIV incidence.

Introduction: HPTN 071 (PopART) implemented a comprehensive HIV prevention package which aimed to reduce HIV incidence within 21 communities of Zambia and South Africa: Arm A, PopART intervention of universal HIV testing and treatment; Arm B, PopART intervention of universal HIV testing with ART provided according to local guidelines; and Arm C, standard of care. Analyses so far have not accounted for the sampling design of the enrolled cohort. We performed a sample-weighted re-analysis of the primary outcome of the PopART trial to derive a population-based estimate of the intervention effect.

Active-Controlled Trial Design for HIV Prevention Trials With a Counterfactual Placebo.

In the quest for enhanced HIV prevention methods, the advent of antiretroviral drugs as pre-exposure prophylaxis (PrEP) has marked a significant stride forward. However, the ethical challenges in conducting placebo-controlled trials for new PrEP agents against a backdrop of highly effective existing PrEP options necessitate innovative approaches. This manuscript delves into the design and implementation of active-controlled trials that incorporate a counterfactual placebo estimate-a theoretical estimate of what HIV incidence would have been without effective prevention.

Estimating the effect of pre-exposure prophylaxis in Black men who have sex with men.

Background: Black men who have sex with men (MSM) are disproportionately burdened by the HIV epidemic in the USA. 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 USA, and it would be unethical and infeasible to do so now.

Adaptive HIV pre-exposure prophylaxis adherence interventions for young women in Johannesburg, South Africa: a sequential multiple-assignment randomised trial.

Background: Adherence to daily oral pre-exposure prophylaxis (PrEP) is low among African young women, and layered support strategies are needed to improve PrEP adherence in this population. We aimed to evaluate potentially scalable adherence-support strategies for young women aged 18-25 years who initiated PrEP in Johannesburg, South Africa.

Methods: We conducted a sequential multiple-assignment randomised trial at Ward 21 of the Wits Reproductive Health and HIV Institute clinical research site, affiliated with University of the Witwatersrand, Johannesburg, South Africa.

High recent PrEP adherence with point-of-care urine tenofovir testing and adherence counselling among young African women: results from the INSIGHT cohort.

Introduction: Adolescent girls and young women (AGYW) account for two-thirds of new HIV infections in Africa. African AGYW have had high uptake of oral HIV pre-exposure prophylaxis (PrEP) but low adherence, which might be improved by point-of-care adherence monitoring with tailored counselling.

Methods: From August 2022 to July 2023, we conducted a PrEP demonstration project with sexually active AGYW ages 16-30 years from 20 sites in South Africa, Eswatini, Kenya, Malawi, Uganda and Zambia.

Evidence-Informed Provision of Doxycycline Post-Exposure Prophylaxis for Prevention of Bacterial Sexually Transmitted Infections.

Doxycycline post-exposure prophylaxis (doxy-PEP) reduces the risk of bacterial sexually transmitted infections (STIs) among men who have sex with men and transgender women. In the United States, doxy-PEP is in an early stage of integration into clinical practice, and national guidelines for its use were recently released. The goal of this manuscript is to provide practical guidance for clinicians who are considering or currently prescribing doxy-PEP.

Establishing adherence-concentration-efficacy thresholds of TDF-FTC pre-exposure prophylaxis for HIV prevention in African women: a protocol for the Women TDF-FTC Benchmark Study.

Background: Oral pre-exposure prophylaxis (PrEP) using co-formulated emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF) is a potent HIV prevention method for men and women, with its efficacy highly dependent on adherence. A pivotal HIV efficacy study combined with a directly observed pharmacological study defined the thresholds for HIV protection in men who have sex with men (MSM), which are the keys to PrEP promotion and development of new PrEP agents. For African women at risk for HIV and belonging to a priority group considered due to disproportionately high incident HIV infections, the variable adherence in PrEP clinical trials and the limited pharmacologic data have resulted in a lack of clarity about the PrEP adherence required for HIV protection.

Associations between HIV stigma and health-related quality-of-life among people living with HIV: cross-sectional analysis of data from HPTN 071 (PopART).

People living with HIV (PLHIV) report lower health-related quality-of-life (HRQoL) than HIV-negative people. HIV stigma may contribute to this. We explored the association between HIV stigma and HRQoL among PLHIV.

An enhanced cross-sectional HIV incidence estimator that incorporates prior HIV test results.

Incidence estimation of HIV infection can be performed using recent infection testing algorithm (RITA) results from a cross-sectional sample. This allows practitioners to understand population trends in the HIV epidemic without having to perform longitudinal follow-up on a cohort of individuals. The utility of the approach is limited by its precision, driven by the (low) sensitivity of the RITA at identifying recent infection.

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).

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.

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.