Brett Hanscom

Brief Report: Preventing HIV-1 Infection in Women Using Oral Preexposure Prophylaxis: A Meta-analysis of Current Evidence.

The World Health Organization has issued an early release revision to its antiretroviral guidelines in which PrEP (Pre-exposure prophylaxis in the form of daily oral, fixed dose combination tenofovir disoproxil fumarate/emtricitabine (TDF/FTC)) is recommended as a prevention option to all people at substantial risk of acquiring HIV. However, lack of effectiveness in two major women-only PrEP trials, VOICE and FEM PrEP, continue to be a cause for concern about achieving effectiveness for women in Southern Africa. We conducted a series of meta-analyses of oral TDF/FTC effectiveness in women including all five randomized placebo-controlled trials that included women. An adherence-based meta-analysis model showed that with high levels of adherence (75%), oral PrEP is estimated to be effective (RR=0.39, 95% CI 0.25 to 0.60). Provided that these results apply to women in Southern Africa, future prevention trial designs in that region should account for potentially reduced HIV incidence when PrEP is available.

Preventing HIV-1 Infection in Women using Oral Pre-Exposure Prophylaxis: A Meta-analysis of Current Evidence.

The World Health Organization has issued an early release revision to its antiretroviral guidelines in which PrEP (Pre-exposure prophylaxis in the form of daily oral, fixed dose combination tenofovir disoproxil fumarate/emtricitabine (TDF/FTC)) is recommended as a prevention option to all people at substantial risk of acquiring HIV. However, lack of effectiveness in two major women-only PrEP trials, VOICE and FEM PrEP, continue to be a cause for concern about achieving effectiveness for women in Southern Africa. We conducted a series of meta-analyses of oral TDF/FTC effectiveness in women including all five randomized placebo-controlled trials that included women. An adherence-based meta-analysis model showed that with high levels of adherence (75%), oral PrEP is estimated to be effective (RR=0.39, 95% CI 0.25 to 0.60). Provided that these results apply to women in Southern Africa, future prevention trial designs in that region should account for potentially reduced HIV incidence when PrEP is available.

Design Issues in Transgender Studies.

Abstract:Transgender individuals constitute an important focus for HIV prevention, but studies in this population present some unique methodologic and operational challenges. We consider issues related to sampling, sample size, number of sites, and trial cost. We discuss relevant design issues for evaluating interventions in both HIV-negative and HIV-infected transgender populations, as well as a method for assessing the impact of an intervention on population HIV incidence. We find that HIV-endpoint studies of transgender individuals will likely require fewer participants but more sites and have higher operational costs than HIV prevention trials in other populations. Because any intervention targeted to transgender individuals will likely include antiretroviral drugs, small scale studies looking at potential interactions between antiretroviral therapy and hormone therapy are recommended. Finally, assessing the impact of an intervention targeted to transgender individuals will require better information on the contribution of such individuals to the population HIV incidence.

A scalable, integrated intervention to engage people who inject drugs in HIV care and medication-assisted treatment (HPTN 074): a randomised, controlled phase 3 feasibility and efficacy study

BACKGROUND People who inject drugs (PWID) have a high incidence of HIV, little access to antiretroviral therapy (ART) and medication-assisted treatment (MAT), and high mortality. We aimed to assess the feasibility of a future controlled trial based on the incidence of HIV, enrolment, retention, and uptake of the intervention, and the efficacy of an integrated and flexible intervention on ART use, viral suppression, and MAT use. METHODS This randomised, controlled vanguard study was run in Kyiv, Ukraine (one community site), Thai Nguyen, Vietnam (two district health centre sites), and Jakarta, Indonesia (one hospital site). PWID who were HIV infected (index participants) and non-infected injection partners were recruited as PWID network units and were eligible for screening if they were aged 18-45 years (updated to 18-60 years 8 months into study), and active injection drug users. Further eligibility criteria for index participants included a viral load of 1000 copies per mL or higher, willingness and ability to recruit at least one injection partner who would be willing to participate. Index participants were randomly assigned via a computer generated sequence accessed through a secure web portal (3:1) to standard of care or intervention, stratified by site. Masking of assignment was not possible due to the nature of intervention. The intervention comprised systems navigation, psychosocial counselling, and ART at any CD4 count. Local ART and MAT services were used. Participants were followed up for 12-24 months. The primary objective was to assess the feasibility of a future randomised controlled trial. To achieve this aim we looked at the following endpoints: HIV incidence among injection partners in the standard of care group, and enrolment and retention of HIV-infected PWID and their injection partners and the uptake of the integrated intervention. The study was also designed to assess the feasibility, barriers, and uptake of the integrated intervention. Endpoints were assessed in a modified intention-to-treat popualtion after exclusion of ineligible participants. This trial is registered on ClinicalTrials.gov, NCT02935296, and is active but not recruiting new participants. FINDINGS Between Feb 5, 2015, and June 3, 2016, 3343 potential index participants were screened, of whom 502 (15%) were eligible and enrolled. 1171 injection partners were referred, and 806 (69%) were eligible and enrolled. Index participants were randomly assigned to intervention (126 [25%]) and standard of care (376 [75%]) groups. At week 52, most living index participants (389 [86%] of 451) and partners (567 [80%] of 710) were retained, and self-reported ART use was higher among index participants in the intervention group than those in the standard of care group (probability ratio [PR] 1·7, 95% CI 1·4-1·9). Viral suppression was also higher in the intervention group than in the standard of care group (PR 1·7, 95% CI 1·3-2·2). Index participants in the intervention group reported more MAT use at 52 weeks than those in the standard of care group (PR 1·7, 95% CI 1·3-2·2). Seven incident HIV infections occurred, and all in injection partners in the standard of care group (intervention incidence 0·0 per 100 person-years, 95% CI 0·0-1·7; standard of care incidence 1·0 per 100 person-years, 95% CI 0·4-2·1; incidence rate difference -1·0 per 100 person-years, 95% CI -2·1 to 1·1). No severe adverse events due to the intervention were recorded. INTERPRETATION This vanguard study provides evidence that a flexible, scalable intervention increases ART and MAT use and reduces mortality among PWID. The low incidence of HIV in both groups impedes a future randomised, controlled trial, but given the strength of the effect of the intervention, its implementation among HIV-infected PWID should be considered. FUNDING US National Institutes of Health.

Expanding Hospital Human Immunodeficiency Virus Testing in the Bronx, New York and Washington, District of Columbia: Results from the HPTN 065 Study

Background Human immunodeficiency virus (HIV) testing is critical for both HIV treatment and prevention. Expanding testing in hospital settings can identify undiagnosed HIV infections. Methods To evaluate the feasibility of universally offering HIV testing during emergency department (ED) visits and inpatient admissions, 9 hospitals in the Bronx, New York and 7 in Washington, District of Columbia (DC) undertook efforts to offer HIV testing routinely. Outcomes included the percentage of encounters with an HIV test, the change from year 1 to year 3, and the percentages of tests that were HIV-positive and new diagnoses. Results From 1 February 2011 to 31 January 2014, HIV tests were conducted during 6.5% of 1621016 ED visits and 13.0% of 361745 inpatient admissions in Bronx hospitals and 13.8% of 729172 ED visits and 22.0% of 150655 inpatient admissions in DC. From year 1 to year 3, testing was stable in the Bronx (ED visits: 6.6% to 6.9%; inpatient admissions: 13.0% to 13.6%), but increased in DC (ED visits: 11.9% to 15.8%; inpatient admissions: 19.0% to 23.9%). In the Bronx, 0.4% (408) of ED HIV tests were positive and 0.3% (277) were new diagnoses; 1.8% (828) of inpatient tests were positive and 0.5% (244) were new diagnoses. In DC, 0.6% (618) of ED tests were positive and 0.4% (404) were new diagnoses; 4.9% (1349) of inpatient tests were positive and 0.7% (189) were new diagnoses. Conclusions Hospitals consistently identified previously undiagnosed HIV infections, but universal offer of HIV testing proved elusive.

HIV prevention trial design in an era of effective pre-exposure prophylaxis.

Pre-exposure prophylaxis (PrEP) has demonstrated remarkable effectiveness protecting at-risk individuals from HIV-1 infection. Despite this record of effectiveness, concerns persist about the diminished protective effect observed in women compared with men and the influence of adherence and risk behaviors on effectiveness in targeted subpopulations. Furthermore, the high prophylactic efficacy of the first PrEP agent, tenofovir disoproxil fumarate/emtricitabine (TDF/FTC), presents challenges for demonstrating the efficacy of new candidates. Trials of new agents would typically require use of non-inferiority (NI) designs in which acceptable efficacy for an experimental agent is determined using pre-defined margins based on the efficacy of the proven active comparator (i.e. TDF/FTC) in placebo-controlled trials. Setting NI margins is a critical step in designing registrational studies. Under- or over-estimation of the margin can call into question the utility of the study in the registration package. The dependence on previous placebo-controlled trials introduces the same issues as external/historical controls. These issues will need to be addressed using trial design features such as re-estimated NI margins, enrichment strategies, run-in periods, crossover between study arms, and adaptive re-estimation of sample sizes. These measures and other innovations can help to ensure that new PrEP agents are made available to the public using stringent standards of evidence.

Adaptive Non-Inferiority Margins under Observable Non-Constancy

A central assumption in the design and conduct of non-inferiority trials is that the active-control therapy will have the same degree of effectiveness in the planned non-inferiority trial as in the prior placebo-controlled trials used to define the non-inferiority margin. This is referred to as the ‘constancy’ assumption. If the constancy assumption fails, decisions based on the chosen non-inferiority margin may be incorrect, and the study runs the risk of approving an inferior product or failing to approve a beneficial product. The constancy assumption cannot be validated in a trial without a placebo arm, and it is unlikely ever to be met completely. When there are strong, observable predictors of constancy, such as dosing and adherence to the active-control product, we can specify conditions where the constancy assumption will likely fail. We propose a method for using measurable predictors of active-control effectiveness to specify non-inferiority margins targeted to the planned study population characteristics. We describe a pre-specified method, using baseline characteristics or post-baseline predictors in the active-control arm, to adapt the non-inferiority margin at the end of the study if constancy is violated. Adaptive margins can help adjust for constancy violations that will inevitably occur in real clinical trials, while maintaining pre-specified levels of Type I error and power.

A Randomized-Controlled Trial of Computer-based Prevention Counseling for HIV-Positive Persons (HPTN 065)

Objective Decreasing the risk of HIV transmission from HIV-positive individuals is an important public health priority. We evaluated the effectiveness of a computer-based sexual risk reduction counseling intervention (CARE+) among HIV-positive persons enrolled in care. Methods HIV-positive eligible participants (N=1075) were enrolled from 11 care sites in the Bronx, NY and Washington, DC and randomized 1:1 to either a tablet-based self-administered CARE+ intervention or standard of care (SOC). The primary outcome was the proportion of participants reporting any unprotected vaginal/anal sex at last sex, among all partners, HIV-negative or HIV-unknown-status partners and for primary and non-primary partners. Results At baseline, 7% of participants in both arms reported unprotected sex with an HIV-negative or HIV-unknown-status partner, while 13% in the CARE+ arm and 17% in the SOC arm reported unprotected sex with any partner. Most participants (88%) were on antiretroviral therapy (ART) at baseline. There was no significant difference in changes over time in unprotected vaginal/anal sex between the CARE+ and SOC arms for any partners (p=0.67) or either HIV-negative or HIV-unknown-status partners (p=0.40). At the Month 12 visit, most participants (85%) either strongly agreed or agreed that computer counseling would be a good addition to in-person counseling by a provider. Conclusion The CARE+ intervention was not effective at reducing sexual risk behaviors among HIV-positive patients in care, most of whom were on ART. Further research may be warranted around the utility of computer-based counseling for HIV prevention.

Regional differences between people who inject drugs in an HIV prevention trial integrating treatment and prevention (HPTN 074): a baseline analysis

People who inject drugs (PWID) experience high HIV incidence and face significant barriers to engagement in HIV care and substance use treatment. Strategies for HIV treatment as prevention and substance use treatment present unique challenges in PWID that may vary regionally. Understanding differences in the risk structure for HIV transmission and disease progression among PWID is essential in developing and effectively targeting intervention strategies of HIV treatment as prevention.