On-Demand Preexposure Prophylaxis in Men at High Risk for HIV-1 Infection

Real-time monitoring and just-in-time intervention for adherence to pre-exposure prophylaxis among men who have sex with men in China: a multicentre RCT study protocol

Background

Pre-exposure prophylaxis (PrEP) is an effective biomedical strategy to prevent transmission of HIV infection, although medication adherence remains a challenge. We present the protocol for a multicentre randomised controlled trial to measure the effectiveness of a real-time monitoring and just-in-time intervention on medication adherence among PrEP users in China.

Methods

Study participants will include 1000 men who have sex with men (MSM) from four cites in China (Shenyang, Beijing, Chongqing and Shenzhen) attending a tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) PrEP project as part of a real-world, prospective multicentre cohort study (CROPrEP). Participants will be randomised into the intervention and control arms in a 1:1 ratio. Participants in the intervention arm will be provided with remote real-time monitoring equipment that triggers twice just-in-time SMS (Short Messaging Service) medication reminders to PrEP users every half an hour when a scheduled dosage is missed, and followed with just-in-time SMS medication reminders to clinicians half an hour when there is no supplement after the second just-in-time SMS reminder to PrEP users. Clinicians will initiate individualised telephone intervention as soon as possible upon receipt of the just-in-time SMS missed dose alert. Those in the control arm will only receive generic weekly SMS reminders. The study will last 6 months. Participants will be seen at follow-up visits at three and 6 months. Trial outcomes to be measured include self-reported adherence assessed via questionnaire and pill counts, as well as drug concentration test results.

Discussion

Medication adherence is critical to achieve optimal benefits from PrEP. This study will be the first individualised behaviour intervention using real-time technology to increase adherence among MSM PrEP users globally. If found effective, a real-time monitoring and just-in-time intervention system may be utilized for improving adherence and thus effectiveness of global PrEP application.

Trial registration

This study registered at ClinicalTrials.gov (ChiCTR1900025604) on September 2, 2019.

Cost-effectiveness and budget effect of pre-exposure prophylaxis for HIV-1 prevention in Germany from 2018 to 2058

BackgroundPre-exposure prophylaxis (PrEP) is a highly effective HIV prevention strategy for men-who-have-sex-with-men (MSM). The high cost of PrEP has until recently been a primary barrier to its use. In 2017, generic PrEP became available, reducing the costs by 90%.AimOur objective was to assess cost-effectiveness and costs of introducing PrEP in Germany.MethodsWe calibrated a deterministic mathematical model to the human immunodeficiency virus (HIV) epidemic among MSM in Germany. PrEP was targeted to 30% of high-risk MSM. It was assumed that PrEP reduces the risk of HIV infection by 85%. Costs were calculated from a healthcare payer perspective using a 40-year time horizon starting in 2018.ResultsPrEP can avert 21,000 infections (interquartile range (IQR): 16,000-27,000) in the short run (after 2 years scale-up and 10 years full implementation). HIV care is predicted to cost EUR 36.2 billion (IQR: 32.4-40.4 billion) over the coming 40 years. PrEP can increase costs by at most EUR 150 million within the first decade after introduction. Ten years after introduction, PrEP can become cost-saving, accumulating to savings of HIV-related costs of EUR 5.1 billion (IQR: 3.5-6.9 billion) after 40 years. In a sensitivity analysis, PrEP remained cost-saving even at a 70% price reduction of antiretroviral drug treatment and a lower effectiveness of PrEP.ConclusionIntroduction of PrEP in Germany is predicted to result in substantial health benefits because of reductions in HIV infections. Short-term financial investments in providing PrEP will result in substantial cost-savings in the long term.

Recovery of Tenofovir-induced Nephrotoxicity following Switch from Tenofovir Disoproxil Fumarate to Tenofovir Alafenamide in Human Immunodeficiency Virus-Positive Patients

Background

Tenofovir disoproxil fumarate (TDF)-induced nephrotoxicity is related to high plasma tenofovir concentrations. Tenofovir alafenamide (TAF) is a tenofovir prodrug with 90% lower plasma tenofovir concentrations. The aim of this study was to evaluate changes in tenofovir-induced nephrotoxicity in Human Immunodeficiency Virus (HIV)-positive patients who switched from TDF to TAF.

Materials and Methods

We identified all HIV-positive patients who switched from elvitegravir/cobicistat/emtricitabine/TDF to elvitegravir/cobicistat/emtricitabine/TAF at a tertiary hospital. We assessed tubulopathy and renal dysfunction before TDF administration, at the time TAF was used following at least 3 months of TDF use, and 3 months after TAF administration. Tubulopathy was defined by the presence of at least three abnormalities in fractional excretion of phosphate, fractional excretion of uric acid, urinary β2-microglobulin, urinary N-acetyl-β-D-glucosaminidase, glucosuria or proteinuria. Renal dysfunction was defined as decreased by more than 25% in the estimated glomerular filtration rate (eGFR) relative to baseline.

Results

In 80 patients, the mean eGFR was 96.8 mL/min/1.73 m² before administration of TDF, 81.2 (P <0.001) at the time of change to TAF, 90.9 (P <0.001) after TAF administration. Renal dysfunction occurred in 19 patients (23.8%) after TDF use for a median 15 months, 11 (57.9%) of these patients recovered from renal dysfunction after TAF administration. Six patients (7.5%) had tubulopathy before TDF administration, 36 (45.0%) after TDF administration (P <0.001), 12 (15.0%) after TAF administration (P = 0.002).

Conclusion

Tenofovir-induced nephrotoxicity in HIV-positive patients receiving TDF was mostly reversible after changing to TAF. Thus, TAF-containing regimens can be administered safely to HIV-positive patients with tenofovir-induced nephrotoxicity.

What are the situational and behavioral factors associated with condomless anal sex without pre-exposure prophylaxis in MSM?

OBJECTIVE

This study aimed to identify situational and behavioral factors associated with condomless anal sex without on-demand PrEP in the open-label extension (OLE) study of the ANRS-IPERGAY trial.

METHODS

Univariable and multivariable modified Poisson regressions with a generalized estimating equation (GEE) were used. The attributable risk percentage for each explanatory variable and for condomless anal sex without PrEP was calculated.

RESULTS

In the OLE, 19% of anal intercourses were unprotected (i.e. no PrEP or condom). Of these, 85% were attributable to sexual intercourse with main partners and 47% with HIV-negative partners. The following factors were positively associated with condomless anal sex without PrEP: a depressive episode in the previous 12 months [aR (95% CI), P-value: 1.49 (1.02--2.17), 0.039], a higher number of sexual intercourses during the previous 4 weeks [1.01 [1.002--1.02], 0.014], and sexual intercourses under the influence of alcohol [1.45 (1.10--1.92), 0.008]. By contrast, condomless anal sex without PrEP was less frequent during sexual intercourses with known casual, unknown casual and multiple partners [0.20 (0.14--0.30), <0.001; 0.10 (0.05--0.20), <0.001; 0.11 (0.05--0.29), <0.001, respectively], as well as with HIV+ partners with an undetectable viral load and HIV+ partners with a detectable/unknown viral load or unknown serology status [0.57 (0.38--0.86), 0.007; 0.52 (0.32--0.87), 0.012, respectively].

CONCLUSION

Choosing to have condomless anal sex without PrEP depends primarily on the sexual partner's characteristics (level of intimacy, serological status). This reflects a form of rationality in HIV risk management. However, our results raise questions about the true efficacy of managing HIV risk using this approach.

Getting more from heterogeneous HIV-1 surveillance data in a high immigration country: estimation of incidence and undiagnosed population size using multiple biomarkers

Background

Most HIV infections originate from individuals who are undiagnosed and unaware of their infection. Estimation of this quantity from surveillance data is hard because there is incomplete knowledge about (i) the time between infection and diagnosis (TI) for the general population, and (ii) the time between immigration and diagnosis for foreign-born persons.

Methods

We developed a new statistical method for estimating the incidence of HIV-1 and the number of undiagnosed people living with HIV (PLHIV), based on dynamic modelling of heterogeneous HIV-1 surveillance data. The methods consist of a Bayesian non-linear mixed effects model using multiple biomarkers to estimate TI of HIV-1-positive individuals, and a novel incidence estimator which distinguishes between endogenous and exogenous infections by modelling explicitly the probability that a foreign-born person was infected either before or after immigration. The incidence estimator allows for direct calculation of the number of undiagnosed persons. The new methodology is illustrated combining heterogeneous surveillance data from Sweden between 2003 and 2015.

Results

A leave-one-out cross-validation study showed that the multiple-biomarker model was more accurate than single biomarkers (mean absolute error 1.01 vs ≥1.95). We estimate that 816 [95% credible interval (CI) 775-865] PLHIV were undiagnosed in 2015, representing a proportion of 10.8% (95% CI 10.3-11.4%) of all PLHIV.

Conclusions

The proposed methodology will enhance the utility of standard surveillance data streams and will be useful to monitor progress towards and compliance with the 90–90-90 UNAIDS target.

HIV Pre-Exposure Prophylaxis (PrEP) Counseling in Germany: Knowledge, Attitudes and Practice in Non-governmental and in Public HIV and STI Testing and Counseling Centers

Background: Providers of sexual health services play an important role in counseling persons at risk of acquiring HIV. The aim of the present study was to investigate the knowledge of and attitudes toward HIV pre-exposure prophylaxis (PrEP) among counselors in non-governmental counseling centers ("NG counseling centers") and in counseling centers of the local health authorities ("local health offices") in Germany and to determine the extent to which PrEP plays a role in their current counseling practice. Methods: An anonymous cross-sectional study using an online questionnaire was conducted among counselors from sexual health centers across Germany. All NG counseling centers in Germany offering HIV testing were asked to participate. For each NG counseling center, a local health office in the same city was also invited. A "knowledge score" and an "attitudes score" were calculated from single items on various relevant aspects. The association of these scores with the proportion of PrEP advice provided proactively in sessions with men who have sex with men (MSM) and trans persons who met the German and Austrian guideline criteria for being offered PrEP ('at-risk clients') was quantified. Results: From Oct. to Dec. 2018, 145 counselors completed the survey. Both self-assessed knowledge of PrEP and attitudes toward PrEP were greater or more positive among counselors from NG counseling centers compared with counselors from local health offices [Median knowledge score (range 0-20): 18.0 (IQR = 5.0) vs. 14.0 (IQR = 4.0), p < 0.001; median attitudes score (range 0-20): 18.0 (IQR = 4.0) vs. 14.0 (IQR = 6.8), p < 0.001]. The proportion of PrEP advice provided proactively in sessions with at-risk clients was larger in counseling centers than in local health offices [50.0% (IQR = 60.0) vs. 30.0% (IQR = 70.0); p = 0.003]. The results of the multiple linear regression model indicate that knowledge and attitudes of the individual counselors, but not the type of center in which they worked, were independent predictors of the proportion of proactive advice on PrEP. Conclusions: There is room for improvement in the current PrEP counseling practice of sexual health services in Germany. The findings of the present study suggest opportunities to improve the implementation of PrEP as part of a comprehensive HIV prevention strategy.

Improving the HIV PrEP continuum of care using an intervention for healthcare providers: a stepped-wedge study protocol

INTRODUCTION

Pre-exposure prophylaxis (PrEP) has demonstrated to be a highly effective method for preventing HIV; however, many individuals with PrEP indications are not receiving PrEP. Primary care settings provide an opportunity to offer PrEP to a wide range of patients. In this paper, we describe the PrEP Optimisation Intervention (PrEP-OI), which includes a PrEP Coordinator and a web-based panel management tool (called PrEP-Rx), and is targeted at healthcare providers (HCPs) to increase PrEP uptake and persistence among those at risk for acquiring HIV.

METHODS AND ANALYSIS

The PrEP-OI study evaluates the efficacy of the PrEP intervention (PrEP Coordinator + PrEP-Rx) to increase PrEP prescriptions through a stepped-wedge design among 10 primary care clinical sites in the San Francisco Department of Public Health. The number of PrEP initiation prescriptions constitute the primary outcome, and we hypothesise that the mean number of PrEP prescriptions written will significantly increase after the clinics initiate PrEP-OI versus before this intervention. Secondary objectives include: 1-differences in PrEP initiation, duration of use and reasons for discontinuation based on patient's age, race/ethnicity and sex/gender, and by clinic and HCP characteristics, 2-sustainability of the intervention during a 12-month follow-up after the stepped-wedge phase, and 3-facilitators and barriers of PrEP delivery and experiences with the proposed PrEP intervention through qualitative interviews with HCPs. The results of this study can provide valuable insight into methods to reduce the burden of PrEP care on HCPs and improve PrEP continuum of care.

ETHICS AND DISSEMINATION

This study and its protocols have been approved by the University of California, San Francisco (UCSF) Institutional Review Board. Study staff will disseminate findings locally (eg, the UCSF Centre for AIDS Prevention Studies' Community Engagement Core), statewide (eg, the California Department of Public Health's Office of AIDS) and nationally and internationally at conferences related to HIV.

TRIAL REGISTRATION NUMBER

NCT03532191.

Predicted Effectiveness of Daily and Nondaily Preexposure Prophylaxis for Men Who Have Sex With Men Based on Sex and Pill-taking Patterns From the Human Immuno Virus Prevention Trials Network 067/ADAPT Study

BACKGROUND

The HIV Prevention Trials Network (HPTN) 067/Alternative Dosing to Augment PrEP Pill Taking (ADAPT) Study evaluated the feasibility of daily and nondaily human immunodeficiency virus (HIV) preexposure prophylaxis (PrEP) regimens among high-risk populations, including men who have sex with men (MSM) and transgender women, in Bangkok, Thailand and Harlem, New York. We used a mathematical model to predict the efficacy and effectiveness of different dosing regimens.

METHODS

An individual-based mathematical model was used to simulate annual HIV incidence among MSM cohorts. PrEP efficacy for covered sex acts, as defined in the HPTN 067/ADAPT protocol, was estimated using subgroup efficacy estimates from the preexposure prophylaxis initiative (iPrEx) trial. Effectiveness was estimated by comparison of the HIV incidence with and without PrEP use.

RESULTS

We estimated that PrEP was highly protective (85%-96% efficacy across regimens and sites) for fully covered acts. PrEP was more protective for partially covered acts in Bangkok (71%-88% efficacy) than in Harlem (62%-81% efficacy). Our model projects 80%, 62%, and 68% effectiveness of daily, time-driven, and event-driven PrEP for MSM in Harlem compared with 90%, 85%, and 79% for MSM in Bangkok. Halving the efficacy for partially covered acts decreases effectiveness by 8-9 percentage points in Harlem and by 5-9 percentage points in Bangkok across regimens.

CONCLUSIONS

Our analysis suggests that PrEP was more effective among MSM in Thailand than in the United States as a result of more fully covered sex acts and more pills taken around partially covered acts. Overall, nondaily PrEP was less effective than daily PrEP, especially in the United States where the sex act coverage associated with daily use was substantially higher.

Comprehensive HIV risk reduction interventions for 2020 and beyond: product choices and effective service-delivery platforms for individual needs and population-level impact

PURPOSE OF REVIEW

This review summarizes key HIV prevention strategies in the 2020 toolkit and discusses opportunities to maximize the public health impact of these prevention interventions at a population level.

RECENT FINDINGS

HIV prevention has relied on counseling, HIV testing, and condom distribution for the past three decades. Recent exciting work has provided evidence on effective HIV prevention interventions, including antiretroviral therapy for HIV prevention, expanding preexposure prophylaxis modalities, and voluntary medical male circumcision which all reduce individual-level HIV risk. Efficient service-delivery approaches are necessary to deliver these products at scale while addressing population-specific needs. These approaches include: making it easier to get individuals HIV tested and linked to prevention services; de-medicalization to increase access to prevention products; creating welcoming clinic service-delivery environments; and integrating HIV prevention products into existing clinical platforms to support ongoing care engagement.

SUMMARY

The 2020 HIV prevention toolkit includes powerful HIV prevention options, and product choice will be increasingly imperative. Meeting ambitious global HIV reduction targets in the next decade will require improved service-delivery platforms to get prevention choices to persons at risk while layering prevention coverage to achieve population-level impact.

Impact of Case Definitions on Efficacy Estimation in Clinical Trials-A Proof-of-Principle Based on Historical Examples

Efficacy estimations in clinical trials are based on case definitions. Commonly, they are a more or less complex set of conditions that have to be fulfilled in order to define a clinical case. In the simplest variant, such a case is identical with a single positive diagnostic test result. Frequently, however, case definitions are more complex. Further, their conditions often ignore the inherent logical structure of symptoms and disease: A symptom or a set of symptoms may be necessary but not sufficient for the unambiguous identification of a case. After describing the structure of case definitions and its impact on efficacy estimations, we exemplify this impact using data from two clinical trials dealing with the effectiveness of the vaginal application of tenofovir gel for the prevention of HIV infections and with the therapeutic effects of fecal transplantation on recurrent Clostridium difficile infections. We demonstrate that the diagnostic performance of case definitions affects efficacy estimations for interventions in clinical trials. The potential risk of bias and uncertainty is high, irrespective of the complexity of the case definition. Accordingly, case definitions in clinical trials should focus on specificity in order to avoid the risk of bias.

Different guidelines for pre-exposure prophylaxis (PrEP) eligibility estimate HIV risk differently: an incidence study in a cohort of HIV-negative men who have sex with men, Portugal, 2014-2018

IntroductionGuidelines for pre-exposure prophylaxis (PrEP) provide criteria to identify individuals at higher risk of HIV infection. We compared the ability to predict HIV seroconversion of four guidelines: the World Health Organization (WHO), the United States Public Health Service and Centers for Disease Control and Prevention (US CDC), the European AIDS Clinical Society (EACS) and the Portuguese National Health Service (PNHS).AimWe aimed to measure the association between guideline-specific eligibility and HIV seroconversion.MethodsWe studied 1,254 participants from the Lisbon Cohort of men who have sex with men with at least two evaluations between March 2014 and March 2018, corresponding to 1,724.54 person-years (PY) of follow-up. We calculated incidence rates (IR) according to each guideline eligibility definition and incident rate ratios (IRR) to test the association between eligibility at baseline and HIV seroconversion.ResultsWe found 28 incident cases (IR: 1.62/100 PY; 95% confidence interval (CI) 1.12-2.35). Guidelines' sensitivity varied from 60.7% (EACS) to 85.7% (PNHS) and specificity varied from 31.8% (US CDC) to 51.5% (EACS). IR was highest among those defined as eligible by the PNHS guideline (2.46/100 PY; IRR = 4.61; 95% CI: 1.60-13.27) and lowest for the WHO guideline (1.89/100 PY; IRR = 1.52; 95% CI: 0.69-3.35).ConclusionsBeing identified as eligible for PrEP was associated with a higher risk of infection. The magnitude of risk varied according to the guideline used. However, the number of HIV infections identified among ineligible participants highlights the potential for missing people who need PrEP.

A novel method to estimate the indirect community benefit of HIV interventions using a microsimulation model of HIV disease

BACKGROUND

Microsimulation models of human immunodeficiency virus (HIV) disease that simulate individual patients one at a time and assess clinical and economic outcomes of HIV interventions often provide key details regarding direct individual clinical benefits ("individual benefit"), but they may lack detail on transmissions, and thus may underestimate an intervention's indirect benefits ("community benefit"). Dynamic transmission models can be used to simulate HIV transmissions, but they may do so at the expense of the clinical detail of microsimulations. We sought to develop, validate, and demonstrate a practical, novel method that can be integrated into existing HIV microsimulation models to capture this community benefit, integrating the effects of reduced transmission while keeping the clinical detail of microsimulations.

METHODS

We developed a new method to capture the community benefit of HIV interventions by estimating HIV transmissions from the primary cohort of interest. The method captures the benefit of averting infections within the cohort of interest by estimating a corresponding gradual decline in incidence within the cohort. For infections averted outside the cohort of interest, our method estimates transmissions averted based on reductions in HIV viral load within the cohort, and the benefit (life-years gained and cost savings) of averting those infections based on the time they were averted. To assess the validity of our method, we paired it with the Cost-effectiveness of Preventing AIDS Complications (CEPAC) Model - a validated and widely-published microsimulation model of HIV disease. We then compared the consistency of model-estimated outcomes against outcomes of a widely-validated dynamic compartmental transmission model of HIV disease, the HIV Optimization and Prevention Economics (HOPE) model, using the intraclass correlation coefficient (ICC) with a two-way mixed effects model. Replicating an analysis done with HOPE, validation endpoints were number of HIV transmissions averted by offering pre-exposure prophylaxis (PrEP) to men who have sex with men (MSM) and people who inject drugs (PWID) in the US at various uptake and efficacy levels. Finally, we demonstrated an application of our method in a different setting by evaluating the clinical and economic outcomes of a PrEP program for MSM in India, a country currently considering PrEP rollout for this high-risk group.

RESULTS

The new method paired with CEPAC demonstrated excellent consistency with the HOPE model (ICC = 0.98 for MSM and 0.99 for PWID). With only the individual benefit of the intervention incorporated, a PrEP program for MSM in India averted 43,000 transmissions over a 5-year period and resulted in a lifetime incremental cost-effectiveness ratio (ICER) of US$2,300/year-of-life saved (YLS) compared to the status quo. After applying both the direct (individual) and indirect (community) benefits, PrEP averted 86,000 transmissions over the same period and resulted in an ICER of US$600/YLS.

CONCLUSIONS

Our method enables HIV microsimulation models that evaluate clinical and economic outcomes of HIV interventions to estimate the community benefit of these interventions (in terms of survival gains and cost savings) efficiently and without sacrificing clinical detail. This method addresses an important methodological gap in health economics microsimulation modeling and allows decision scientists to make more accurate policy recommendations.

Intracellular Tenofovir-Diphosphate and Emtricitabine-Triphosphate in Dried Blood Spots Following Tenofovir Alafenamide: The TAF-DBS Study

BACKGROUND

Tenofovir alafenamide (TAF), in combination with FTC, was recently approved for PrEP in the United States. The objective of this study was to assess the relationship between tenofovir-diphosphate (TFV-DP) and emtricitabine-triphosphate (FTC-TP) in dried blood spots (DBS) with adherence to TAF/FTC.

METHODS

TAF-DBS was a randomized, crossover clinical study of TFV-DP in DBS, following directly observed dosing of 33%, 67%, or 100% of daily TAF (25 mg)/FTC (200 mg). Healthy volunteers were randomized to 2 different, 12-week dosing regimens, separated by a 12-week washout. DBS were collected weekly. TFV-DP and FTC-TP were extracted from two 7-mm punches and assayed with LC-MS/MS.

RESULTS

Thirty-seven participants (17 female, 7 African American, and 6 Hispanic) were included. TFV-DP exhibited a mean half-life of 20.8 days (95% confidence interval: 19.3 to 21.3). The slope for TFV-DP versus dosing arm was 1.14 (90% confidence interval: 1.07 to 1.21). The mean (SD) TFV-DP after 12 weeks was 657 (186), 1451 (501), and 2381 (601) fmol/2 7-mm punches for the 33%, 67%, and 100% arms. The following adherence interpretations are proposed: <450 fmol/punches, <2 doses/wk; 450-949 fmol/punches, 2-3 doses/wk; 950-1799 fmol/punches, 4-6 doses/wk; and ≥1800 fmol/punches, 7 doses/wk. FTC-TP was quantifiable for 1 week after drug cessation in 50%, 92%, and 100% of participants in the 33%, 67%, and 100% arms, respectively.

CONCLUSION

TFV-DP in DBS after TAF/FTC exhibited a long half-life and was linearly associated with dosing, similar to its predecessor tenofovir disoproxil fumarate. FTC-TP was quantifiable for up to 1 week after drug cessation. Together, these moieties provide complementary measures of cumulative adherence and recent dosing for TAF/FTC.

Pre-exposure prophylaxis among men who have sex with men in Côte d'Ivoire: a quantitative study of acceptability

This cross sectional study was conducted in 2018 in Côte d'Ivoire to assess PrEP acceptability among men who have sex with men (MSM). Two hundred and one men were asked on their intention to use PrEP if made available. Logistic regression accounting for the sampling design was used to analyze associations between high PrEP acceptability and different independent variables including barriers and facilitators. Participants were mostly young (mean age = 25 years), educated (82% with secondary/postsecondary education) and single (95.5%). On average, 3.4 episodes of anal sex were reported monthly and 37.8% of men did not use a condom at last sex. Most MSM (72.6%) had heard of PrEP before enrollment. Overall, 35.3% reported that they would use PrEP very probably if made available. In multivariate analysis, factors associated with high PrEP acceptability were condom use at last sexual intercourse (Odds ratio (OR) = 2.51; 95%Confidence interval (95%CI) = 1.45-4.33); insertive sex as compared to versatile sex (OR = 2.56; 95%CI = 1.14-5.67); free PrEP delivery (OR = 2.45; 95%CI = 1.07-5.59), concerns about side effects (OR = 0.66; 95%CI = 0.48-0.90), and being preoccupied by the fact that post-PrEP antiretroviral therapy could be inefficient (OR = 0.25; 95%CI = 0.14-0.44). PrEP implementation among MSM in Côte d'Ivoire should be accompanied by awareness raising campaigns explaining its utility.

Clinical targeting of HIV capsid protein with a long-acting small molecule

Oral antiretroviral agents provide life-saving treatments for millions of people living with HIV, and can prevent new infections via pre-exposure prophylaxis^1-5. However, some people living with HIV who are heavily treatment-experienced have limited or no treatment options, owing to multidrug resistance⁶. In addition, suboptimal adherence to oral daily regimens can negatively affect the outcome of treatment-which contributes to virologic failure, resistance generation and viral transmission-as well as of pre-exposure prophylaxis, leading to new infections^1,2,4,7-9. Long-acting agents from new antiretroviral classes can provide much-needed treatment options for people living with HIV who are heavily treatment-experienced, and additionally can improve adherence¹⁰. Here we describe GS-6207, a small molecule that disrupts the functions of HIV capsid protein and is amenable to long-acting therapy owing to its high potency, low in vivo systemic clearance and slow release kinetics from the subcutaneous injection site. Drawing on X-ray crystallographic information, we designed GS-6207 to bind tightly at a conserved interface between capsid protein monomers, where it interferes with capsid-protein-mediated interactions between proteins that are essential for multiple phases of the viral replication cycle. GS-6207 exhibits antiviral activity at picomolar concentrations against all subtypes of HIV-1 that we tested, and shows high synergy and no cross-resistance with approved antiretroviral drugs. In phase-1 clinical studies, monotherapy with a single subcutaneous dose of GS-6207 (450 mg) resulted in a mean log₁₀-transformed reduction of plasma viral load of 2.2 after 9 days, and showed sustained plasma exposure at antivirally active concentrations for more than 6 months. These results provide clinical validation for therapies that target the functions of HIV capsid protein, and demonstrate the potential of GS-6207 as a long-acting agent to treat or prevent infection with HIV.

A review of HIV pre-exposure prophylaxis (PrEP) programmes by delivery models in the Asia-Pacific through the healthcare accessibility framework

INTRODUCTION

In the Asia-Pacific, pre-exposure prophylaxis (PrEP) is a newly introduced public health intervention for minimizing HIV transmission, the coverage of which has remained limited. The best delivery models and strategies for broadening access of the vulnerable communities are not fully known. This review identified PrEP programmes reported in the Asia-Pacific, which were classified by delivery models and assessed with a healthcare accessibility framework.

METHODS

We performed a literature search on PubMed and Ovid MEDLINE using relevant search terms, manual searched grey literature by visiting relevant websites, examined reference lists and contacted authors for clarification of included PrEP programmes reported through July 2019. A structured table was used for data extraction and summarizing findings in accordance with the five constructs of approachability, acceptability, availability, affordability and appropriateness grounded in the conceptual framework of Healthcare Accessibility.

RESULTS AND DISCUSSION

This literature search yielded a total of 1308 publications; 119 full texts and abstracts were screened, and 24 publications were included in the review. We identified 11 programmes implemented in seven cities/countries in the Asia-Pacific. A typology of four PrEP delivery models was delineated: (a) fee-based public service model; (b) fee-based community setting model; (c) free public service model; and (d) free community setting model. Overall, the free community setting model was most commonly adopted in the Asia-Pacific, with the strength to boost the capacity of facility and human resources, which enhanced "approachability", "availability" and "acceptability." The free public service model was characterized by components designed in improving "approachability," "availability" and "appropriateness," with attention on equity in accessing PrEP. Among free-based models, long-term affordability both to the government and PrEP users would need to be maximized to increase accessibility. Alongside the need for raising awareness, supportive environments and ensuring timely access were means for enabling the development of a sustainable PrEP service.

CONCLUSION

PrEP programmes could be classified by delivery models through the five constructs of healthcare accessibility. While the coverage of PrEP remains limited in the Asia-Pacific, an evaluation of these models could benchmark best practices, which would in turn allow effective models to be designed.

Renal impairment: an unnecessary barrier to HIV prevention

The use of tenofovir disoproxil fumarate (TDF) in combination with emtricitabine, prescribed for pre-exposure prophylaxis (PrEP), is highly effective at reducing incident sexually transmissible HIV infection among those at risk. TDF is associated with proteinuria, Fanconi syndrome and chronic kidney disease, and is not recommended for use in patients with an estimated creatinine clearance <60 mL min-1. There are currently no Pharmaceutical Benefits Scheme (PBS)-funded PrEP options for patients at risk of HIV infection with moderate renal impairment in Australia. This report describes the case of a patient who acquired HIV soon after PrEP was suspended due to moderate renal impairment. The various clinical and regulatory issues this case raises are discussed.

Durable protection against repeated penile exposures to simian-human immunodeficiency virus by broadly neutralizing antibodies

Penile acquisition of HIV accounts for most infections among men globally. Nevertheless, candidate HIV interventions for men advance to clinical trials without preclinical efficacy data, due primarily to a paucity of relevant animal models of penile HIV infection. Using our recently developed macaque model, we show that a single subcutaneous administration of broadly neutralizing antibody (bNAb) 10-1074 conferred durable protection against repeated penile exposures to simian-human immunodeficiency virus (SHIV_SF162P3). Macaques co-administered bNAbs 10-1074 and 3BNC117, or 3BNC117 alone, also exhibited significant protection against repeated vaginal SHIV_AD8-EO exposures. Regression modeling estimated that individual plasma bNAb concentrations of 5 μg ml^-1 correlated with ≥99.9% relative reduction in SHIV infection probability via penile (10-1074) or vaginal (10-1074 or 3BNC117) challenge routes. These results demonstrate that comparably large reductions in penile and vaginal SHIV infection risk among macaques were achieved at clinically relevant plasma bNAb concentrations and inform dose selection for the development of bNAbs as long-acting pre-exposure prophylaxis candidates for use by men and women.

PrEP 1.0 and Beyond: Optimizing a Biobehavioral Intervention

Tenofovir disoproxil fumarate coformulated with emtricitabine (TDF/FTC) was shown to be effective in preventing HIV acquisition when used for pre-exposure prophylaxis (PrEP), but questions have arisen regarding optimal PrEP implementation strategies.

The dynamics of a simple, risk-structured HIV model

Many diseases, such as HIV, are heterogeneous for risk. In this paper, we study an infectious-disease model for a population with demography, mass-action incidence, an arbitrary number of risk classes, and separable mixing. We complement our general analyses with two specific examples. In the first example, the mean of the components of the transmission coefficients decreases as we add more risk classes. In the second example, the mean stays constant but the variance decreases. For each example, we determine the disease-free equilibrium, the basic reproduction number, and the endemic equilibrium. We also characterize the spectrum of eigenvalues that determine the stability of the endemic equilibrium. For both examples, the basic reproduction number decreases as we add more risk classes. The endemic equilibrium, when present, is asymptotically stable. Our analyses suggest that risk structure must be modeled correctly, since different risk structures, with similar mean properties, can produce different dynamics.

Perspectives on HIV PrEP care in Germany: qualitative insights from primary care physicians and specialists

Recently, research has shifted from investigating the effectiveness of HIV pre-exposure prophylaxis (PrEP) to strategizing its implementation. Several European studies have explored physicians' perspectives on implementing PrEP in diverse settings, yet there are no data on the situation in Germany. The purpose of this study was to explore physicians' perspectives on current PrEP care in Germany. From April to July 2018, we conducted 16 semi-structured interviews with HIV providers (HIVPs) and primary care physicians (PCPs). Transcripts were analyzed using thematic content analysis. Physicians showed varying levels of PrEP expertise. Many PCPs lacked knowledge about PrEP. Some PCPs did not support the idea of PrEP as a prophylactic option. Opinions about PCPs' role in PrEP care were diverging, yet most PCPs favored referring PrEP clients to an HIVP or opted for a shared-care arrangement. Perceived problems included stigma and lack of privacy for PrEP care in rural areas. Our findings highlight the need for tailored physician training, which should be addressed in PrEP implementation in Germany.

A Survey on HIV/AIDS-Related Knowledge, Attitudes, Risk Behaviors, and Characteristics of Men Who Have Sex with Men among University Students in Guangxi, China

In recent years, the prevalence of human immunodeficiency virus (HIV) infection among Chinese university students has increased significantly, and HIV transmission among men who have sex with men (MSM) comprises more than half of the new cases. There is still a lack of research investigating the incidence of male-to-male sex, the attitudes towards MSM, and the awareness of HIV/AIDS among university students in Guangxi, one of the HIV high-risk areas in China. Therefore, we performed a cross-sectional investigation among 578 male students, recruited by stratified sampling, in universities in Nanning, Guangxi, between January 2016 and March 2017. Researcher-administered anonymous questionnaires were completed. Self-recognition as MSM was found in 8.48% of the subjects. Compared with non-MSM, university student MSM included more people over the age of 20 (OR = 4.95), had less migration from other districts of Guangxi (OR = 0.26), and the majority were nonmedical students (OR = 8.99). In total, 63.25% of the male student participants reported a lack of acceptance of MSM, while 35.47% acknowledged barriers between themselves and acquaintances who were MSM. Overall, 67.30% of the subjects correctly answered questions related to AIDS knowledge. The proportion of MSM subjects who answered the AIDS-related questions completely correctly was significantly lower than that of non-MSM subjects (42.86% vs. 69. 57%, respectively, OR: 0.33), but the self-recognition risk of MSM was significantly higher than that of non-MSM (OR = 2.59). Risky behaviors associated with HIV infections, including smoking, alcohol consumption, drug abuse, and inconsistent condom use, were significantly higher among the MSM participants. The percentages of student's willingness to accept MC and PrEP were 70.93% and 77.51%, respectively. These results raise the alarm that university student MSM in Guangxi, China, require urgent public attention and more effective health education, including the education on MC and PrEP.

Trends in HIV pre-exposure prophylaxis uptake in Ontario, Canada, and impact of policy changes: a population-based analysis of projected pharmacy data (2015-2018)

Objectives

HIV pre-exposure prophylaxis (PrEP) is a proven tool for HIV prevention, but PrEP use in Ontario, Canada, and the effects of recent policies are unknown. We estimated the number and characteristics of PrEP users in Ontario and evaluated the impacts of policy changes between July 2015 and June 2018.

Methods

We obtained tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) dispensation data for Ontario from IQVIA, and applied an algorithm to identify use for PrEP. We report prevalent PrEP use for the second quarter of 2018 according to age, sex, region, prescriber specialty, and payer type, and generate “PrEP-to-need ratios” (PNR) by dividing these numbers by the estimated numbers of new HIV diagnoses. We used interventional autoregressive integrated moving average models to examine the impact of three policy changes on PrEP use: Health Canada approval (February 2016), availability of generic TDF/FTC and partial public drug coverage (September 2017), and public drug coverage for individuals aged < 25 years (January 2018).

Results

The estimated number of individuals receiving PrEP increased 713%, from 374 in 2015 Q3 to 3041 in 2018 Q2. Among PrEP users in 2018 Q2, 97.5% were male, 60.4% were < 40 years, 67.7% obtained PrEP from a family physician, 77.2% used private insurance, and 67.0% were in Toronto. PNRs were highest in 30–39-year-olds, males, Toronto and the Central East and West regions. Time series analyses found that Health Canada approval (p = 0.0001) and introducing generics/partial public drug coverage (p = 0.002) led to significantly increased use.

Conclusions

PrEP use has risen in Ontario in association with favourable policy changes, but remains far below guideline recommendations.

Electronic supplementary material

The online version of this article (10.17269/s41997-020-00332-3) contains supplementary material, which is available to authorized users.

Brief Report: Incidence of HIV in a Nationwide Cohort Receiving Pre-exposure Prophylaxis for HIV Prevention

BACKGROUND

Cases of HIV, while infrequent, have been reported during tenofovir disoproxil fumarate/emtricitabine use as pre-exposure prophylaxis (PrEP). We describe the incidence of HIV and patterns of PrEP use within the Veterans Health Administration (VHA).

METHODS

We conducted a retrospective cohort study among persons initiating PrEP in the VHA between July 2012 and April 2016 using national VHA data. We defined time on PrEP and time at risk of HIV exposure as the total time from the first PrEP fill to exhaustion of supply of the final PrEP prescription. We identified incident cases of HIV infection after PrEP initiation based on laboratory data. Medication adherence measures and days without pills were calculated using pharmacy fill data. We used a chart review to determine patient-reported PrEP use around the time of diagnosis.

RESULTS

We identified 825 unique patients initiating PrEP; they were 97% men and 67% white, with a mean age of 41 years. Six HIV infections were observed during the study period, yielding an HIV incidence of 0.8 (Poisson exact 95% confidence interval: 0.3 to 1.8) cases per 100 person-years. Two cases occurred during active PrEP use by self-report and perfect adherence based on fill data. Both were infected with viruses containing the M184V mutation. Four additional cases were diagnosed after self-reported discontinuation.

CONCLUSIONS

HIV infection was rare in a nationwide cohort of PrEP users. Although most of the infections occurred during inconsistent PrEP use, infections during periods of high measured adherence were also observed. These findings highlight the importance of PrEP persistence during periods of risk.

Tail-phase safety, tolerability, and pharmacokinetics of long-acting injectable cabotegravir in HIV-uninfected adults: a secondary analysis of the HPTN 077 trial

BACKGROUND

Long-acting injectable cabotegravir is a novel integrase inhibitor currently in advanced clinical development for HIV prevention and treatment. We aimed to assess the terminal phase pharmacokinetics and safety of long-acting injectable cabotegravir in participants included in the HPTN 077 trial.

METHODS

HPTN 077 was a multicentre, double-blind, randomised, placebo-controlled phase 2a trial done at eight sites in Brazil, Malawi, South Africa, and the USA. Participants (aged 18-65 years), who were HIV-uninfected and at low-risk for HIV, were randomly assigned (3:1) to long-acting injectable cabotegravir (800 mg given three times at 12 week intervals or 600 mg given five times, administered at one 4 week interval, and every 8 weeks thereafter) or placebo. Participants were followed up to 76 weeks after final injection. In a prespecified analysis of secondary and exploratory outcomes, we assessed the safety, measured by the proportion of participants with grade 2 or worse adverse events, and pharmacokinetics, measured by apparent terminal phase half-life (t_1/2app) and estimated time to lower limit of quantification (LLOQ) of long-acting injectable cabotegravir during the injection phase (defined as the time between first injection and 12 weeks or 8 weeks after the last injection in cohort 1 or cohort 2 respectively) and tail phase (defined as the time between final injection and 52-76 weeks post-final injection). Safety was analysed in all participants who received at least one injection. Pharmacokinetic analyses included all participants who had received at least one injection and had at least three cabotegravir measurements higher than the LLOQ after the final injection. Pharmacokinetic outcomes were estimated using non-compartmental methods. The trial is completed, and was registered with ClinicalTrials.gov, NCT02178800.

FINDINGS

Between Feb 9, 2015, and May 27, 2016, 177 participants (134 participants in the cabotegravir group [74 participants in cohort 1; 60 participants in cohort 2] and 43 participants in the placebo group [25 participants in cohort 1; 18 participants in cohort 2) were enrolled and received at least one injection and thus were included in the safety analysis. The incidence of grade 2 or worse adverse events was significantly lower during the tail phase than the injection phase (p<0·0001). At 52-60 weeks after final injection, nine (23%) of 40 male participants had detectable cabotegravir concentrations and at week 76, four (13%) of 30 male participants had detectable cabotegravir concentrations compared with 52 (63%) of 82 female participants and 27 (42%) of 64 female participants at the same timepoints. The median time from the last injection to the time when cabotegravir concentration decreased below the LLOQ was 43·7 weeks (IQR 31·1-66·6; range 20·4-152·5) for male participants and 67·3 weeks (29·1-89·6; 17·7-225·5) for female participants (p=0·0003). t_1/2app was longer for female participants than male participants (geometric mean fold-change 1·33, 95% CI 1·06-1·68; p=0·014), and longer for participants with a high body-mass index (BMI) than those with a low BMI (1·31, 1·06-1·63; p=0·015).

INTERPRETATION

The clinical significance of the long pharmacokinetic tail of cabotegravir observed in female participants compared with male participants, and those with higher BMI compared with a lower BMI, need to be addressed in future trials.

FUNDING

National Institute of Allergy and Infectious Diseases.

Preexposure Prophylaxis for Mitigating Risk of HIV Transmission During HIV Cure-Related Clinical Trials With a Treatment Interruption

Analytical treatment interruption performed during human immunodeficiency virus (HIV) cure-related clinical trials exposes sex partners of participants in these trials to a risk of HIV transmission. Preexposure prophylaxis (PrEP), which emerged in recent years as a key strategy for preventing HIV transmission, is often considered a useful tool to prevent this risk. This article supports offering PrEP to the stable sex partners of participants in these trials but also notes limitations that must be addressed. It concludes that PrEP cannot on its own eliminate the risk of secondary transmission in this context.

High uptake of pre-exposure prophylaxis (PrEP) during early roll-out in Belgium: results from surveillance reports

Background Since 1 June 2017, oral pre-exposure prophylaxis (PrEP) could be prescribed and reimbursed in Belgium as prophylactic medication for people who are at increased risk of HIV acquisition. The aim of this study was to determine the uptake of daily and event-driven PrEP in Belgium during the first 9 months of roll-out.

METHODS

Routine aggregated data on the number of reimbursement requests and the number of boxes of Truvada (Gilead Sciences, Cambridge, UK) delivered for PrEP through the Belgian pharmacies were obtained from the National Institute for Health and Disability Insurance. We also collected aggregated data from seven Aids Reference Centres (ARCs) currently providing most of the PrEP care in Belgium.

RESULTS

From 1 June 2017 to 28 February 2018, 1352 requests for reimbursement were approved by the National Institute for Health and Disability Insurance. Almost 98% of those who bought at least one box of 30 tablets of emtricitabine 200mg/tenofovir disoproxil fumarate 300mg (FTC/TDF) in a Belgian pharmacy were male, and most (67%) were between 30 and 50 years of age. According to data obtained from ARCs, the proportion of those choosing event-driven PrEP initially ranged between 29% and 73%.

CONCLUSIONS

The uptake of PrEP in Belgium since the start of the roll-out in June 2017 has been high, and almost entirely limited to men who have sex with men, of whom 43% initially prefer a non-daily regimen. A better understanding is needed as to why other populations, such as sub-Saharan African migrants, are not accessing PrEP, as well as the development of a more sustainable PrEP delivery model.

Early experience of implementing a national HIV pre-exposure prophylaxis service in Wales, United Kingdom 2017

Background Pre-exposure prophylaxis (PrEP) was introduced in Sexual Health Services of the Welsh National Health Service (NHS Wales) in July 2017 as a 3-year pilot service.

METHODS

Data were collected through the pre-existing Sexual Health in Wales Surveillance System, to which codes were added to capture PrEP eligibility, outcome of offer of PrEP, reasons for declining and adherence. Eligibility categories were defined based on nationally agreed criteria: men who have sex with men (MSM) and transgender people at high risk of HIV acquisition; partners of HIV-positive individuals not known to be virally suppressed; and heterosexuals reporting condomless intercourse with a HIV-positive individual not known to be virally suppressed.

RESULTS

During the first 6 months, 516 people were eligible, 96% of which were MSM. Overall, 57% of those eligible (296/516) started PrEP. Reasons for declining PrEP were given by 88 (56%) of 157 people; 50 (57%) of whom did not believe themselves to be at risk. Of the available adherence assessments, 89% considered that all risk episodes had been covered. Persistence at 3 months was assessed for 141 people, of which 93 (66%) were still using PrEP. There were no HIV diagnoses in people taking PrEP during the first 6 months. Twenty-nine people were diagnosed with 37 episodes of sexually transmissible infections (STIs) while on PrEP. STI incidence was 105.7 per 100 person-years.

CONCLUSIONS

The early trend indicates that implementation of PrEP is progressing as planned, and the service has been utilised by clients. This analysis can help refine implementation, inform planning and research around uptake, use and effect in Wales and internationally.

Enumerating the population eligible for funded HIV pre-exposure prophylaxis (PrEP) in New Zealand

Background Pre-exposure prophylaxis (PrEP) became publicly funded in New Zealand (NZ) on 1 March 2018. PrEP could have a substantial population-level effect on HIV transmission if scaled up rapidly. An accurate estimate of the size of the PrEP-eligible population would guide implementation.

METHODS

We drew on nine sources to estimate the PrEP-eligible population, namely Statistics NZ data, Pharmaceutical Management Agency (PHARMAC) data on adults receiving funded antiretroviral treatment (ART), expert advice, estimates of the HIV care cascade, surveillance of undiagnosed HIV in a community sample of gay and bisexual men (GBM), surveillance of HIV diagnoses, NZ Health Survey data on sexual orientation among males, behavioural surveillance among GBM and behavioural data among people living with HIV (PLWH) from the HIV Futures NZ study. From these sources we derived three estimates relating to GBM, non-GBM and total eligible population. Sensitivity analyses examined different assumptions (GBM denominators, proportion PLWH diagnosed, proportion of diagnosed PLWH treated).

RESULTS

We estimated that 17.9% of sexually active HIV-negative GBM would be eligible for PrEP, equating to 5816 individuals. We estimated that 31 non-GBM individuals would be eligible for PrEP. Thus, in total, 5847 individuals would be eligible for PrEP, comprising 99.5% GBM and 0.5% non-GBM. Sensitivity analyses ranged from 3062 to 6718 individuals.

CONCLUSIONS

Policy makers can use enumeration to monitor the speed and scale in coverage as implementation of publicly funded PrEP proceeds. Sexual health and primary care services can use enumeration to forecast PrEP demand and plan accordingly. Better quality data, especially on transgender adults in NZ, would improve the accuracy of estimates.

Baseline characteristics of gay and bisexual men in a HIV pre-exposure prophylaxis demonstration project with equity quotas in Auckland, New Zealand

Background In New Zealand, pre-exposure prophylaxis (PrEP) should target gay and bisexual men (GBM), and equity is an important principle. Baseline characteristics of GBM offered PrEP in a demonstration project with an enrolment quota of 50% non-Europeans are described.

METHODS

An open-label, single-arm treatment evaluation study design ('NZPrEP') was used. The settings were four publicly funded sexual health clinics in Auckland in 2017. The study population was 150 GBM recruited from clinics, community sources and social media. Participants self-completed an online questionnaire about PrEP awareness, attitudes and sexual risk behaviour in the last 3 months. Baseline characteristics are described and examined to determine whether these were associated with PrEP initiation status (self-referral vs doctor/nurse recommendation).

RESULTS

In total, 150 GBM of whom half (52%) were non-European, including 21.3% Maori, 19.3% Asian and 8.7% Pacific, were enrolled into the study. Two-thirds (65.3%) self-referred for PrEP and one-third (34.7%) were recommended PrEP by the doctor/nurse. Participants reported a high number of male condomless receptive anal intercourse partners (MenAICLR) (median 3, range 0-50), with 10% reporting 10 or more MenAICLR and 45.3% reporting group sex. In the previous year, 65.3% had a sexually transmissible infection (STI); 18% had rectal chlamydia or gonorrhoea at enrolment. Almost half (47.7%) had recently used drugs with sex, including 8.1% who used methamphetamine. Participants recommended PrEP had lower education, lived less centrally and had a higher STI prevalence than PrEP self-referrers, but their risk behaviour was similar.

CONCLUSIONS

Early PrEP adopters in New Zealand have high HIV risk. Demonstration projects should consider equity mechanisms so that minorities can participate meaningfully.

Tenofovir and emtricitabine resistance among antiretroviral-naive patients in the Canadian Observational Cohort Collaboration: implications for PrEP

BACKGROUND

The real-world effectiveness of pre-exposure prophylaxis (PrEP) may be influenced by circulating HIV strains resistant to either tenofovir or emtricitabine. Yet, few studies have examined rates of resistance to these drugs in clinical settings.

METHODS

We conducted a retrospective cohort study of antiretroviral-naive participants in the Canadian Observational Cohort collaboration who initiated antiretroviral therapy between 2006 and 2014. In separate analyses, we determined the prevalence of pretherapy resistance and cumulative incidence of follow-up resistance to tenofovir and emtricitabine. We used multivariable proportional hazards models to examine associations between baseline variables and the development of resistance.

RESULTS

We studied 6,622 antiretroviral-naive participants initiating therapy, of whom 5,428 (82.0%) had a baseline resistance test. Baseline resistance to tenofovir and emtricitabine was observed in 83 (1.5%) and 21 (0.4%) patients, respectively. Among patients without baseline resistance, the cumulative incidence of resistance to tenofovir and emtricitabine 5 years following treatment initiation was 0.0070 (95% CI 0.0046, 0.0095) and 0.033 (95% CI 0.028, 0.038), respectively. Following multivariable analysis, a baseline viral load ≥100,000 copies/ml was associated with emergence of tenofovir (hazard ratio [HR] 2.88; 95% CI 1.35, 6.15) and emtricitabine (HR 2.27; 95% CI 1.64, 3.15) resistance. Initiating an integrase inhibitor-based regimen and CD4⁺ T-cell count below 200 cells/mm³ were also associated with resistance to each drug.

CONCLUSIONS

We observed a low prevalence of baseline resistance and a low incidence of emergence of resistance to tenofovir and emtricitabine among antiretroviral-naive patients in routine clinical care.

Phase 1 Pharmacokinetic Trial of 2 Intravaginal Rings Containing Different Dose Strengths of Vicriviroc (MK-4176) and MK-2048

BACKGROUND

Vaginal rings (VRs) are a promising approach for sustained delivery of antiretroviral (ARV) medication to prevent human immunodeficiency virus (HIV) infection in women. Combination ARV VRs could increase efficacy.

METHODS

MTN-028, a phase 1 trial in 19 HIV-uninfected women, evaluated 2 VRs containing vicriviroc (VCV) and MK-2048. Participants were randomized 2:1 to a low-dose (VCV, 91 mg; MK-2048, 10 mg) or original-dose (VCV, 182 mg; MK-2048, 30 mg) ring used for 28 days. Safety was assessed by documenting adverse events (AEs). Drug concentrations were evaluated in plasma, cervicovaginal fluid (CVF), and cervical tissue samples.

RESULTS

All AEs reported were grade 1 or 2, with no statistically significant differences in related genitourinary AEs or grade ≥2 AEs observed between arms (P = >.99). VCV/MK-2048 concentrations rose rapidly, with higher plasma area under the concentration-time curve (AUC) in the original-dose arm (geometric mean ratio, 3.29 for VCV and 1.49 for MK-2048) and similar AUCs across arms for CVF samples. Cervical tissue concentrations were higher in the original-dose arm (geometric mean ratio, 7.94 for VCV and 6.45 for MK-2048), with greater drug released based on residual drug levels. Plasma and CVF concentrations for both drugs fell rapidly after ring removal.

CONCLUSIONS

In this first study evaluating 2 doses of a combination VCV/MK-2048 VR, both rings were found to be safe and well tolerated. VCV and MK-2048 were detectable in plasma, CVF, and cervical tissue samples, and drug release and plasma drug exposure were higher for the original-dose than for the low-dose ring.

High incidence of HCV in HIV-negative men who have sex with men using pre-exposure prophylaxis

BACKGROUND & AIMS

HCV has emerged as a sexually transmitted infection (STI) among HIV-positive men who have sex with men (MSM). We evaluated HCV incidence and its risk factors among HIV-negative MSM using HIV pre-exposure prophylaxis (PrEP).

METHODS

Participants of the Amsterdam PrEP project were tested for HCV antibodies or HCV-RNA every 6 months. Participants used daily or event-driven PrEP and could switch regimens during follow-up. We calculated incidence rates (IRs) for overall HCV infection and separately for primary and re-infection. A univariable Bayesian exponential survival model was used to identify risk factors associated with incident HCV infection. The HCV NS5B gene fragment (709 bp) was sequenced and compared to HCV isolates from HIV-positive MSM and other risk groups (n = 419) using phylogenetic analysis.

RESULTS

Among 350 participants contributing 653.6 person-years (PYs), we detected 15 HCV infections in 14 participants (IR = 2.30/100PY). There were 8 primary infections (IR = 1.27/100PY) and 7 re-infections (IR = 27.8/100PY). IR was 2.71/100PY in daily and 1.15/100PY in event-driven PrEP users. Factors associated with incident HCV infection were higher number of receptive condomless anal sex acts with casual partners (posterior hazard ratio [HR] 1.57 per ln increase; 95% credibility interval [CrI] 1.09-2.20), anal STI (posterior HR 2.93; 95% CrI 1.24-7.13), injecting drug use (posterior HR 4.69; 95% CrI 1.61-12.09) and sharing straws when snorting drugs (posterior HR 2.62; 95% CrI 1.09-6.02). We identified robust MSM-specific HCV clusters of subtypes 1a, 4d, 2b and 3a, which included MSM with and without HIV.

CONCLUSIONS

HIV-negative MSM using PrEP are at risk of incident HCV infection, while identified risk factors are similar to those in HIV-positive MSM. Regular HCV testing is needed, especially for those with a previous HCV infection and those reporting risk factors.

LAY SUMMARY

We report that hepatitis C virus infections are frequently acquired among HIV-negative men who have sex with men (MSM) using pre-exposure prophylaxis to prevent HIV infection. New infections occurred more frequently in those reporting receptive anal sex without using condoms, having an anal sexually transmitted infection, injecting drugs, and sharing straws when snorting drugs. The viruses found in HIV-negative men using pre-exposure prophylaxis are genetically similar to those in HIV-positive men, but not in other hepatitis C risk groups, suggesting that (sexual) transmission is occurring between HIV-positive MSM and HIV-negative MSM using pre-exposure prophylaxis.

CLINICAL TRIAL NUMBER

Dutch trial registration number NTR5411.

The impact of self-selection based on HIV risk on the cost-effectiveness of preexposure prophylaxis in South Africa

OBJECTIVES

We explored the impact and cost-effectiveness of preexposure prophylaxis (PrEP) provision to different populations in South Africa, with and without effective self-selection by individuals at highest risk of contracting HIV (through concurrent partnerships and/or commercial sex).

DESIGN AND METHODS

We used a previously developed HIV transmission model to analyse the epidemiological impact of PrEP provision to adolescents, young adults, pregnant women, female sex workers (FSWs) and (MSM), and data from South African PrEP programmes to estimate the cost and cost-effectiveness of PrEP (cost in 2019 USD per HIV infection averted over 20 years, 2019, 38). PrEP uptake followed data from early implementation sites, scaled-up linearly over 3 years, with target coverage set to 18% for adolescents, young adults and pregnant women, 30% for FSW and 54% for MSM.

RESULTS

The annual cost of PrEP provision ranges between $75 and $134 per person. PrEP provision adolescents and young adults, regardless of risk behaviour, will each avert 3.2--4.8% of HIV infections over 20 years; provision to high-risk individuals only has similar impact at lower total cost. The incremental cost per HIV infection averted is lower in high-risk vs. all-risk sub-populations within female adolescents ($507 vs. $4537), male adolescents ($2108 vs. $5637), young women ($1592 vs. $10 323) and young men ($2605 vs. $7715), becoming cost saving within 20 years for high-risk adolescents, young women, MSM and FSWs.

CONCLUSION

PrEP is an expensive prevention intervention but uptake by those at the highest risk of HIV infection will make it more cost-effective, and cost-saving after 14-18 years.

Biomedical HIV Protection Among Gay and Bisexual Men Who Use Crystal Methamphetamine

Use of crystal methamphetamine (crystal) among gay and bisexual men (GBM) has been associated with condomless anal intercourse with casual partners (CLAIC) and HIV infection. Pre-exposure prophylaxis (PrEP) and undetectable viral load (UVL) are important biomedical HIV prevention strategies. We investigate the relationship between crystal use and HIV sexual risk behaviours in the context of PrEP and UVL. In 2018, 1367 GBM provided details about crystal use and HIV prevention strategies. Binary logistic regression was used to estimate associations between crystal use and behaviour. Recent crystal use was independently associated with greater social engagement with gay men and having more sexual partners. Crystal use was also independently associated with use of PrEP and UVL among GBM who engaged in CLAIC. Although GBM who used crystal were more likely to have engaged in CLAIC, they were also more likely to use biomedical HIV prevention which mitigates against the risks of HIV infection.

Assessing determinants of pre-exposure prophylaxis (PrEP) adherence among a sample of rural Midwestern men who have sex with men (MSM)

Pre-exposure prophylaxis (PrEP) efficacy in preventing HIV among gay, bisexual, and other men who have sex with men (MSM) is dependent upon adherence. Little is known about the PrEP adherence experiences among MSM who live in rural areas of the US. This qualitative study was informed by a modified version of Straussian Grounded Theory. Thirty-four 34 rural Midwestern MSM participated in telephone interviews that assessed their PrEP adherence factors. Overall, participants adhered to the PrEP regimen, ranging from missing none to a couple of doses per month. Participants had high self-efficacy (competence) and self-reliance (autonomy) in taking PrEP daily. Participants incorporated PrEP into their already existing routines. Participants were motivated to adhere to prevent HIV acquisition and be financially responsible. All participants mentioned their PrEP provider discussed the importance of adherence with PrEP's effectiveness, but future patient-provider PrEP adherence communication varied among participants. Future PrEP adherence interventions should address counseling strategies that leverage these constructs to support pill taking. Future research should explore patient-provider conversations surrounding PrEP adherence to inform provider- and patient-level interventions.

Vaccines and Broadly Neutralizing Antibodies for HIV-1 Prevention

Development of improved approaches for HIV-1 prevention will likely be required for a durable end to the global AIDS pandemic. Recent advances in preclinical studies and early phase clinical trials offer renewed promise for immunologic strategies for blocking acquisition of HIV-1 infection. Clinical trials are currently underway to evaluate the efficacy of two vaccine candidates and a broadly neutralizing antibody (bNAb) to prevent HIV-1 infection in humans. However, the vast diversity of HIV-1 is a major challenge for both active and passive immunization. Here we review current immunologic strategies for HIV-1 prevention, with a focus on current and next-generation vaccines and bNAbs.

Pre-exposure Prophylaxis Use and Medication Adherence Among Men Who Have Sex With Men: A Systematic Review of the Literature

The appropriate use of pre-exposure prophylaxis (PrEP) by men who have sex with men (MSM) can be highly effective at reducing HIV transmission. Our review examined prevalence estimates, sexual behaviors, and medication adherence among MSM PrEP users in high-income countries. Articles published between January 2008 and December 2018 were identified through Medline, Web of Science, CINAHL, and CENTRAL. The search identified 643 publications, of which 52 were included in the final synthesis. We found that PrEP initiation was not consistently associated with significant changes in sexual behavior, but some users may have risk compensated. A minority of MSM used PrEP, and they had high levels of adherence. PrEP-related stigma, side effects, and psychosocial factors lead to nonadherence. A daily routine, pill boxes, alarms/texts, and education can promote adherence. Further research is required to examine PrEP impact on sexual behavior and factors that influence adherence in high-risk MSM subpopulations.

Male partners' influence on women's acceptance and use of PrEP products across two high HIV-burdened districts in South Africa

The demonstrated efficacy of pre-exposure prophylaxis (PrEP) has brought hope of controlling the epidemic among women with limited HIV preventation options. Several studies have demonstrated the importance of male partner involvement in female sexual and reproductive health but there is limited research on male involvement in the adoption of HIV prevention methods among women. Using a culture-centred approach, this article discusses perceptions of female-initiated HIV prevention methods among men and women. The data were collected using eight sex-specific focus group discussions with a sample of men and women aged between 18 and 49 years from selected urban and rural settings in two provinces of South Africa, KwaZulu-Natal and Mpumalanga. Thematic analysis was utilised to identify four key themes: increased infidelity in relationships and risky behaviour; association of PrEP with casual relationships; a partner's right to know that women are reducing their risk of HIV infection; and that men need to engage in decision-making on HIV risk reduction. The article highlights the importance of partner engagement and knowledge sharing of female-initiated prevention methods as part of a combination HIV-prevention strategy, and the urgency of creating enabling environments to utilise female-initiated methods.

HIV Seroconversion in the Era of Pharmacologic Prevention: A Case-Control Study at a San Francisco STD Clinic

BACKGROUND

The comparative effectiveness of pre- and post-exposure prophylaxis (PrEP and PEP) for men who have sex with men (MSM) is unclear.

SETTING

We conducted a case-control study of MSM who were initially HIV-uninfected during September 1, 2012-June 30, 2016 at San Francisco's only municipal sexually transmitted diseases (STDs) clinic.

METHODS

Each case was matched with up to 3 controls based on age, baseline visit date, and follow-up time. The primary dependent variable was HIV seroconversion; the primary independent variable was exposure to PrEP, PEP, or neither. Conditional logistic regression was used to calculate odds ratios and 95% confidence intervals.

RESULTS

Of 638 MSM (161 cases and 477 controls), 137 reported ever taking PrEP, 98 reported taking PEP-only, and 403 took neither. PrEP takers had more non-HIV sexually transmitted diseases during the analysis (72.3% vs. 55.1% vs. 42.4% P < 0.01) and were more likely to report receptive anal sex in the past 3 months (86.5% vs. 80.4% vs. 73.0%; P < 0.01). In the adjusted model, PrEP was associated with lower odds of HIV seroconversion (odds ratio 0.24; 95% confidence interval: 0.13 to 0.46) while PEP use had no effect on HIV acquisition compared with taking neither.

CONCLUSIONS

MSM who ever used PrEP demonstrated equal or higher sexual risk compared with those using neither PrEP nor PEP but had 76% lower odds of HIV seroconversion. MSM who used PEP but never PrEP were no less likely to seroconvert than those using neither. MSM should be offered PrEP. PEP users with ongoing risk of HIV infection should be connected to PrEP after PEP.

Shared HCV Transmission Networks Among HIV-1-Positive and HIV-1-Negative Men Having Sex With Men by Ultradeep Sequencing

OBJECTIVE

Several studies reported hepatitis C virus (HCV) transmission networks among men having sex with men (MSM) in Europe and the spread of HCV strains from HIV-HCV coinfected toward HCV monoinfected MSM. We aimed to investigate HCV transmission dynamics among HIV-positive and HIV-negative MSM by ultradeep sequencing (UDS).

DESIGN AND METHODS

NS5B fragment (388 bp) was sequenced from virus of 50 HIV-positive and 18 HIV-negative patients diagnosed with recent HCV infection. UDS data were analyzed by Geneious (version 10.3.2). Phylogenetic trees were constructed by FastTree (version 2.1) and submitted to ClusterPicker (version 1.2.3) for transmission chain detection at different thresholds of maximum genetic distance (MGD) (3% for Sanger, 3% and 4.5% for UDS).

RESULTS

Ten, 17, and 18 HCV transmission chains were identified by Sanger at 3%, UDS at 3% and at 4.5% of MGD, respectively. Of 68 subjects enrolled, 38 (55.9%), 38 (55.9%), and 43 (65.3%) individuals were involved in transmission networks found by Sanger at 3%, UDS at 3%, and at 4.5% of MGD, respectively. Mixed transmission chains including HIV-positive and HIV-negative subjects were detected for 8/10 chains by Sanger at 3%, for 9/17 by UDS at 3%, and for 10/18 by UDS at 4.5% of MGD. Overall, the number of HIV-negative individuals clustering with HIV-positive ones was 9/18 by Sanger, 9/18 by UDS at 3%, and 10/18 by UDS at 4.5% of MGD.

CONCLUSIONS

HIV-positive and HIV-negative MSM shared HCV transmission networks, which emphasizes the need for HCV surveillance and prevention measures in these communities regardless of the HIV status.

Estimation and correction of bias in network simulations based on respondent-driven sampling data

Respondent-driven sampling (RDS) is widely used for collecting data on hard-to-reach populations, including information about the structure of the networks connecting the individuals. Characterizing network features can be important for designing and evaluating health programs, particularly those that involve infectious disease transmission. While the validity of population proportions estimated from RDS-based datasets has been well studied, little is known about potential biases in inference about network structure from RDS. We developed a mathematical and statistical platform to simulate network structures with exponential random graph models, and to mimic the data generation mechanisms produced by RDS. We used this framework to characterize biases in three important network statistics – density/mean degree, homophily, and transitivity. Generalized linear models were used to predict the network statistics of the original network from the network statistics of the sample network and observable sample design features. We found that RDS may introduce significant biases in the estimation of density/mean degree and transitivity, and may exaggerate homophily when preferential recruitment occurs. Adjustments to network-generating statistics derived from the prediction models could substantially improve validity of simulated networks in terms of density, and could reduce bias in replicating mean degree, homophily, and transitivity from the original network.

Strategies used by gay male HIV serodiscordant couples to reduce the risk of HIV transmission from anal intercourse in three countries

INTRODUCTION

There are few data about the range of strategies used to prevent sexual HIV transmission within gay male serodiscordant couples. We examined HIV prevention strategies used by such couples and compared differences between countries.

METHODS

Opposites Attract was a cohort study of male serodiscordant couples in Australia, Brazil and Thailand, from May 2014 (Australia) or May 2016 (Brazil/Thailand) to December 2016. At visits, HIV-positive partners had viral load (VL) tested; HIV-negative partners reported sexual behaviour and perceptions of their HIV-positive partner's VL results. Within-couple acts of condomless anal intercourse (CLAI) were categorized by strategy: condom-protected, biomedically protected (undetectable VL and/or pre-exposure prophylaxis [PrEP]), or not protected by either (HIV-negative partners engaging in insertive CLAI, receptive CLAI with withdrawal, or receptive CLAI with ejaculation).

RESULTS

A total of 343 couples were included in this analysis (153 in Australia, 93 in Brazil and 97 in Thailand). Three-quarters of HIV-positive partners were consistently virally suppressed (<200 copies/mL) during follow-up, and HIV-negative partners had correct perceptions of their partner's VL result for 76.5% of tests. One-third of HIV-negative partners used daily PrEP during follow-up. Over follow-up, 73.8% of couples had CLAI. HIV-negative partners reported 31,532 acts of anal intercourse with their HIV-positive partner. Of these, 46.7% were protected by condoms, 48.6% by a biomedical strategy and 4.7% of acts were not protected by these strategies. Australian couples had fewer condom-protected acts and a higher proportion of biomedically protected acts than Brazilian and Thai couples. Of the 1473 CLAI acts where the perceived VL was detectable/unknown and were not protected by PrEP (4.7% of all acts), two-thirds (n = 983) were when the HIV-negative partner was insertive (strategic positioning). Of the 490 acts when the HIV-negative partner was receptive, 261 involved withdrawal and 280 involved ejaculation. Thus, <1% of acts were in the highest risk category of receptive CLAI with ejaculation.

CONCLUSIONS

Couples used condoms, PrEP or perceived undetectable VL for prevention in the majority of anal intercourse acts. Only a very small proportion of events were not protected by these strategies. Variation between countries may reflect differences in access to HIV treatment, education, knowledge and attitudes.

Brief Report: Routine Use of Oral PrEP in a Phase 2 Rectal Microbicide Study of Tenofovir Reduced-Glycerin 1% Gel (MTN-017)

BACKGROUND

As daily oral preexposure prophylaxis (PrEP) becomes standard for HIV prevention, routine use of PrEP is likely to increase within clinical trials of novel preventive agents. We describe the prevalence and characteristics of participants reporting nonstudy oral PrEP use within Microbicide Trials Network-017 (MTN-017), a phase 2 trial of a rectal microbicide.

SETTING AND METHODS

One hundred ninety-five HIV-uninfected men who have sex with men and transgender women were enrolled and followed in MTN-017 across 8 sites in the United States, Thailand, South Africa, and Peru from 2013 to 2015. Nonstudy oral PrEP use was recorded on case report forms and progress notes. Characteristics of PrEP users and non-PrEP users were compared using tests of statistical significance.

RESULTS

Overall, 11% of participants reported nonstudy oral PrEP use, all from the San Francisco (SF) site, accounting for 58% (22/38) of participants enrolled in SF. There was a higher median number of sex partners reported in the past 8 weeks before enrollment among oral PrEP users vs. nonusers (7 vs. 2, P = 0.02). Most PrEP users (18/22, 82%) began PrEP treatment during screening/after enrollment, and most (19/22, 86%) decided to continue oral PrEP after study completion.

CONCLUSION

Nonstudy oral PrEP use in the first phase 2 study of tenofovir reduced-glycerin 1% gel was high at a single site in SF where community PrEP availability and use was expanding. Investigators should consider the evolving context of nonstudy oral PrEP use across trial sites when designing and interpreting trials of novel biomedical prevention modalities.

Pleasure and PrEP: Pleasure-Seeking Plays a Role in Prevention Choices and Could Lead to PrEP Initiation

Pleasure-seeking plays a role in prevention (means choices and use), and in the sexual quality of life of men who have sex with men (MSM). Since HIV is a major threat to MSM health, new means of prevention, like pre-exposure prophylaxis (PrEP), must meet the needs of MSM to be fully efficient. Using a psychosocial approach, we examined how pleasure-seeking plays a role in participation of MSM in “ANRS-IPERGAY,” a community-based trial on sexual health which included sexual on-demand PrEP. Thirteen semistructured collective interviews were conducted with 45 participants. First, we analyzed participants’ search for new prevention means due to previous failures in condom use. We found that participants perceived condoms as a barrier—both materially and symbolically—to pleasure and desire, causing anxiety and stress considering sexual intercourse. Second, we explored representations and attitudes concerning pleasure within the context of PrEP. We found that PrEP allowed participants to freely choose their desired sexual positions and to better enjoy intimacy. Third, we studied the sexual quality of life for PrEP users in ANRS-IPERGAY and found an improvement. Thanks to the community-based design of the trial, this new prevention tool became a means to develop agency and empowerment for participants, not only in negotiating individual prevention but also in opposing the normative and stigmatizing discourse on sexuality and HIV. In conclusion, pleasure-seeking appears to be an essential element of sexual fulfillment that needs to be integrated as a positive notion in the study of HIV prevention.