Could disparities in PrEP uptake limit the public health benefit?

The need for a health equity framework in next-generation pre-exposure prophylaxis implementation

Pre-exposure prophylaxis (PrEP) is highly effective for prevention of HIV transmission and plays an important role in efforts to end the HIV epidemic within the next decade. However, disparities in access to PrEP might be fuelling disparities in the burden of HIV in the USA. The advent of next-generation PrEP formulations that do not involve daily regimens (eg, long-acting cabotegravir) holds potential to facilitate medication adherence, but if the roll-out of these formulations does not consider disparities in access, HIV disparities might be further widened. On the basis of US epidemiological data and informed by the Theory of Fundamental Causes of Health Disparities, we propose an equity-promoting framework to guide the implementation of daily oral and next-generation PrEP. Multilevel efforts to bolster equity in PrEP care include generating demand for next-generation PrEP formulations among marginalised groups, expanding the availability of health services providing oral and next-generation PrEP, and addressing structural and financial barriers to HIV prevention care. The aim of these strategies is to realise the potential of next-generation PrEP to provide people at high risk with effective options to prevent HIV acquisition, thereby helping to reduce both overall HIV transmission and health disparities in the USA.

Antiretroviral Drugs for Treatment and Prevention of HIV Infection in Adults: 2022 Recommendations of the International Antiviral Society-USA Panel

Importance

Recent advances in treatment and prevention of HIV warrant updated recommendations to guide optimal practice.

Objective

Based on a critical evaluation of new data, to provide clinicians with recommendations on use of antiretroviral drugs for the treatment and prevention of HIV, laboratory monitoring, care of people aging with HIV, substance use disorder and HIV, and new challenges in people with HIV, including COVID-19 and monkeypox virus infection.

Evidence Review

A panel of volunteer expert physician scientists were appointed to update the 2020 consensus recommendations. Relevant evidence in the literature (PubMed and Embase searches, which initially yielded 7891 unique citations, of which 834 were considered relevant) and studies presented at peer-reviewed scientific conferences between January 2020 and October 2022 were considered.

Findings

Initiation of antiretroviral therapy (ART) is recommended as soon as possible after diagnosis of HIV. Barriers to care should be addressed, including ensuring access to ART and adherence support. Integrase strand transfer inhibitor-containing regimens remain the mainstay of initial therapy. For people who have achieved viral suppression with a daily oral regimen, long-acting injectable therapy with cabotegravir plus rilpivirine given as infrequently as every 2 months is now an option. Weight gain and metabolic complications have been linked to certain antiretroviral medications; novel strategies to ameliorate these complications are needed. Management of comorbidities throughout the life span is increasingly important, because people with HIV are living longer and confronting the health challenges of aging. In addition, management of substance use disorder in people with HIV requires an evidence-based, integrated approach. Options for preexposure prophylaxis include oral medications (tenofovir disoproxil fumarate or tenofovir alafenamide plus emtricitabine) and, for the first time, a long-acting injectable agent, cabotegravir. Recent global health emergencies, like the SARS-CoV-2 pandemic and monkeypox virus outbreak, continue to have a major effect on people with HIV and the delivery of services. To address these and other challenges, an equity-based approach is essential.

Conclusions and Relevance

Advances in treatment and prevention of HIV continue to improve outcomes, but challenges and opportunities remain.

Spillover benefit of pre-exposure prophylaxis for HIV prevention: evaluating the importance of effect modification using an agent-based model

We developed an agent-based model using a trial emulation approach to quantify effect measure modification of spillover effects of pre-exposure prophylaxis (PrEP) for HIV among men who have sex with men (MSM) in the Atlanta-Sandy Springs-Roswell metropolitan area, Georgia. PrEP may impact not only the individual prescribed, but also their partners and beyond, known as spillover. We simulated a two-stage randomised trial with eligible components (≥3 agents with ≥1 HIV+ agent) first randomised to intervention or control (no PrEP). Within intervention components, agents were randomised to PrEP with coverage of 70%, providing insight into a high PrEP coverage strategy. We evaluated effect modification by component-level characteristics and estimated spillover effects on HIV incidence using an extension of randomisation-based estimators. We observed an attenuation of the spillover effect when agents were in components with a higher prevalence of either drug use or bridging potential (if an agent acts as a mediator between ≥2 connected groups of agents). The estimated spillover effects were larger in magnitude among components with either higher HIV prevalence or greater density (number of existing partnerships compared to all possible partnerships). Consideration of effect modification is important when evaluating the spillover of PrEP among MSM.

Estimating the percentage of European MSM eligible for PrEP: insights from a bio-behavioural survey in thirteen cities

OBJECTIVES

This paper aims to estimate the percentage of European men who have sex with men (MSM) who may benefit from pre-exposure prophylaxis (PrEP), applying the three most widely used HIV risk indices for MSM (MSM Risk Index, Menza score, San Diego Early Test (SDET) score) and drawing on a large-scale multisite bio-behavioural survey (Sialon II).

METHODS

The Sialon II study was a bio-behavioural survey among MSM implemented in 13 European cities using either time-location sampling or respondent-driven sampling. Biological and behavioural data from 4901 MSM were collected. Only behavioural data of HIV-negative individuals were considered. Three widely used risk indices to assess HIV acquisition risk among MSM were used to estimate individual HIV risk scores and PrEP eligibility criteria.

RESULTS

4219 HIV-negative MSM were considered. Regardless the HIV risk score used and the city, percentages of MSM eligible for PrEP were found to range between 5.19% and 73.84%. Overall, the MSM Risk Index and the Menza score yielded broadly similar percentages, whereas the SDET Index provided estimates constantly lower across all cities. Although all the three scores correlated positively (r>0.6), their concordance was highly variable (0.01<CCC<0.62).

CONCLUSION

Our findings showed the impact of different scoring systems on the estimation of the percentage of MSM who may benefit from PrEP in European cities. Although our primary aim was not to compare the performance of different HIV risk scores, data show that a considerable percentage of MSM in each city should be offered PrEP in order to reduce HIV infections. As PrEP is highly effective at preventing HIV among MSM, our findings provide useful, practical guidance for stakeholders in implementing PrEP at city level to tackle HIV infections in Europe.