Ending the HIV Epidemic: A Plan for the United States

Phylodynamic Analysis Complements Partner Services by Identifying Acute and Unreported HIV Transmission

Tailoring public health responses to growing HIV transmission clusters depends on accurately mapping the risk network through which it spreads and identifying acute infections that represent the leading edge of cluster growth. HIV transmission links, especially those involving persons with acute HIV infection (AHI), can be difficult to uncover, or confirm during partner services investigations. We integrated molecular, epidemiologic, serologic and behavioral data to infer and evaluate transmission linkages between participants of a prospective study of AHI conducted in North Carolina, New York City and San Francisco from 2011-2013. Among the 547 participants with newly diagnosed HIV with polymerase sequences, 465 sex partners were reported, of whom only 35 (7.5%) had HIV sequences. Among these 35 contacts, 23 (65.7%) links were genetically supported and 12 (34.3%) were not. Only five links were reported between participants with AHI but none were genetically supported. In contrast, phylodynamic inference identified 102 unreported transmission links, including 12 between persons with AHI. Importantly, all putative transmission links between persons with AHI were found among large clusters with more than five members. Taken together, the presence of putative links between acute participants who did not name each other as contacts that are found only among large clusters underscores the potential for unobserved or undiagnosed intermediaries. Phylodynamics identified many more links than partner services alone and, if routinely and rapidly integrated, can illuminate transmission patterns not readily captured by partner services investigations.

Prevention of HIV Transmission and the HPTN 052 Study

The HIV Prevention Trials Network 052 study (HPTN 052) was a clinical trial designed to determine whether early treatment for HIV infection prevented transmission of the virus in couples where one partner was infected with HIV and the other was not, referred to as HIV serodiscordant or serodifferent couples. The study enrolled 1,763 couples at 13 sites in 9 countries in Asia, Africa, and the Americas. HPTN 052 demonstrated a minimum of 96% reduction of HIV in heterosexual couples ascribed to antiretroviral treatment; early treatment of HIV significantly reduced other infections in the HIV-infected subjects. This study, in conjunction with similar research, led to significant changes in international HIV treatment guidelines and the concept of treatment as prevention (TasP). This article provides the scientific background and history of how HPTN 052 came into being, the challenges it faced, and the ultimate impact it had on the fields of HIV treatment and prevention.

Methods for county-level estimation of pre-exposure prophylaxis coverage and application to the U.S. Ending the HIV Epidemic jurisdictions

PURPOSE

Pre-exposure prophylaxis (PrEP) is a pillar of the US Department of Health and Human Services "Ending the HIV Epidemic" (EHE) initiative in 50 EHE jurisdictions (48 U.S. counties and two U.S. cities) and seven U.S. states with high numbers of HIV diagnoses rates in rural areas. Current data systems do not provide data on PrEP uptake in counties or cities.

METHODS

We report on PrEP users at the county level. Data from a large, commercial pharmacy database were used; we applied the U.S. Census Bureau's method to allocate PrEP users within a ZIP3 into counties and validated the results. We report counts and rates of PrEP users in 2018 for all EHE jurisdictions. We used joinpoint regression to model the estimated annual percent change in PrEP use for each jurisdiction and state.

RESULTS

93,156 people in the 50 EHE jurisdictions used PrEP in 2018; 94% were men and 39% were aged 25-34 years. There was more than an 80-fold difference in the range of rates of PrEP use per 100,000 population among the EHE jurisdictions (range: 8-644 per 100,000 population; median 93 per 100,000 population). PrEP use increased from 2012 to 2018 in all EHE counties and states. At current rates of growth of PrEP use, 94% of EHE counties and jurisdictions will reach their National HIV/AIDS Strategy goals of a 500% increase in PrEP use in 2020. EHE states had less variation in rates of PrEP use (range: 29-51/100,000 population; median 32/100,000 population).

CONCLUSIONS

At the outset of a major U.S. government program to reduce HIV infections, rates of PrEP use are highly variable among the 50 EHE jurisdictions. Data from commercial prescription databases will be a useful public resource to understand progress in promoting use of PrEP as part of the EHE initiative and evaluating progress in PrEP use across health jurisdictions.

Electronic medical record alert activation increase hepatitis C and HIV screening rates in primary care practices within a large healthcare system

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The electronic medical record alert improved screening for HCV and HIV.

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91% of HCV and 100% of HIV positive patients were linked into care.

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Low post-intervention screening rates suggest additional interventions are required.

Societal and economic burdens of hepatitis C virus (HCV) and human immunodeficiency virus (HIV) continue to grow. The Centers for Disease Control and Prevention recommends a one-time HCV screen for individuals in the Baby Boomer population (those born between 1945 and 1965) and a one-time HIV screen for all individuals between ages 13–64 years regardless of risk factors, with more frequent screening for both conditions based on individual risk factors.

This study took place at Atrium Health, a healthcare system with approximately 12 million patient encounters per year. The aims of this study were to assess the impact of the HCV and HIV electronic medical record (EMR) alerts recently implemented on screening rates and linkage to care.

Data were collected from 12 primary care practices. Implementation of EMR alerts increased HCV and HIV screening from 1,934 of 59,632 (3.2%) to 13,726 of 60,422 (22.7%) and 6,950 of 112,813 (6.2%) to 12,379 of 109,173 (11.3%) respectively. The HCV screening resulted in an increase of patients with antibody positive results having a subsequent RNA test from 68% (122/179) to 98% (430/442). 74 of 81 (91%) of HCV and 15 of 15 (100%) of HIV positive patients were linked into care.

The addition of an EMR alert was associated with improved screening for HCV and HIV in primary care practices. Screening all patients decreases testing stigma since there is a lowered risk of disease transmission for those who test positive. However, post-intervention screening rates indicate further opportunities exist for additional interventions to increase screening rates.

A Crowdsourcing Open Contest to Design Pre-Exposure Prophylaxis Promotion Messages: Protocol for an Exploratory Mixed Methods Study

Background

In the United States, black men who have sex with men (BMSM) are disproportionately affected by HIV. Pre-exposure prophylaxis (PrEP) can reduce HIV incidence. However, real-world implementation of PrEP outside of clinical trials has identified racial disparities in PrEP awareness, uptake, and adherence. In the context of a long history of medical mistrust and power imbalances between scientists and community members, strategies to increase uptake of PrEP among BMSM should consider ways to ensure messages address the needs and priorities of the community. Crowdsourcing contests shift traditional individual tasks to a large group and may enhance community engagement.

Objective

This paper describes the research protocol of a contest approach to soliciting PrEP promotion messages among BMSM in Baltimore.

Methods

Open-contest implementation and evaluation will proceed as follows: (1) organize a community steering group; (2) develop platforms to solicit crowd input; (3) engage the community to contribute ideas through a Web-based forum and in-person events; (4) evaluate contest entries using both community panel judge assessment and crowd voting; (5) utilize mixed methods to evaluate feasibility, acceptability, and community engagement; and (6) disseminate contest results.

Results

This study was funded by the National Institutes of Health (National Institute of Mental Health: R34MH116725) in May 2018 and was approved by the institutional review board in April 2018. The open contest started in February 2019, and data analyses for the mixed method evaluation are expected to complete in December 2019.

Conclusions

The contest will potentially bring new ideas in developing more impactful and locally defined PrEP promotion campaigns. We will determine whether an open-contest approach is acceptable among BMSM in Baltimore. If successful, this study can inform future projects using a similar approach on how to identify and implement programs and policies that are more responsive to community needs and that build up community assets.

International Registered Report Identifier (IRRID)

DERR1-10.2196/15590

Patterns of alcohol use and associated characteristics and HIV-related outcomes among a sample of African-American women living with HIV

BACKGROUND

Alcohol use is common among people living with HIV and negatively impacts care and outcomes. African-American women living with HIV are subject to vulnerabilities that may increase risk for alcohol use and associated HIV-related outcomes.

METHODS

We used baseline data from a randomized controlled trial of an HIV-related stigma-reduction intervention among African-American women living with HIV in Chicago and Birmingham (2013-2015). Patterns of alcohol use [any use, unhealthy alcohol use (UAU), heavy episodic drinking (HED)] were measured using the AUDIT-C. We assessed demographic, social, and clinical characteristics which may influence alcohol use and HIV-related outcomes which may be influenced by patterns of alcohol use in bivariate and multivariable analyses.

RESULTS

Among 220 African-American women living with HIV, 54 % reported any alcohol use, 24 % reported UAU, and 27 % reported HED. In bivariate analysis, greater depressive symptoms, lower religiosity, lower social support, marijuana, and crack/cocaine use were associated with patterns of alcohol use (p < 0.05). Marijuana and cocaine/crack use were associated with patterns of alcohol use in adjusted analysis (p < 0.05). In adjusted analysis, any alcohol use and HED were associated with lower likelihood of ART adherence (ARR = 0.72, 95 % CI: 0.53-0.97 and ARR = 0.65, 95 % CI: 0.44-0.96, respectively), and UAU was associated with lack of viral suppression (ARR = 0.78, 95 % CI: 0.63-0.96).

CONCLUSIONS

Findings suggest any and unhealthy alcohol use is common and associated with poor HIV-related outcomes in this population. Regular alcohol screening and intervention should be offered, potentially targeted to subgroups (e.g., those with other substance use).

The Invisible US Hispanic/Latino HIV Crisis: Addressing Gaps in the National Response

The federal government has proposed an end to HIV transmission in the United States by 2030. Although the United States has made substantial overall progress in the fight against HIV/AIDS, data released by the Centers for Disease Control and Prevention have raised concerns about widening, yet largely unrecognized, HIV infection disparities among Hispanic and Latino populations.This commentary identifies underlying drivers of increasing new HIV infections among Hispanics/Latinos, discusses existing national efforts to fight HIV in Hispanic/Latino communities, and points to gaps in the federal response. Consideration of the underlying drivers of increased HIV incidence among Hispanics/Latinos is warranted to achieve the administration's 2030 HIV/AIDS goals.Specifically, the proposed reinforcement of national efforts to end the US HIV epidemic must include focused investment in four priority areas: (1) HIV stigma reduction in Hispanic/Latino communities, (2) the availability and accessibility of HIV treatment of HIV-positive Hispanics/Latinos, (3) the development of behavioral interventions tailored to Hispanic/Latino populations, and (4) the engagement of Hispanic/Latino community leaders.

Social, Clinical, and Behavioral Determinants of HIV Infection and HIV Testing among Black Men in Toronto, Ontario: A Classification and Regression Tree Analysis

Black men bear a disproportionate burden of HIV infection. These HIV inequities are influenced by intersecting social, clinical, and behavioral factors. The purpose of this analysis was to determine the combinations of factors that were most predictive of HIV infection and HIV testing among black men in Toronto. Classification and regression tree analysis was applied to secondary data collected from black men (N = 460) in Toronto, 82% of whom only had sex with women and 18% whom had sex with men at least once. For HIV infection, 10 subgroups were identified and characterized by number of lifetime male partners, age, syphilis history, and perceived stigma. Number of lifetime male partners was the best single predictor of HIV infection. For HIV testing, the analysis identified 8 subgroups characterized by age, condom use, number of sex partners and Chlamydia history. Age (>24 years old) was the best single predictor of HIV testing.

Prescribing HIV pre-exposure prophylaxis: A qualitative analysis of health care provider training needs

Increasing the number of pre-exposure prophylaxis (PrEP) prescriptions will require more health care providers to be willing and trained to prescribe the medication. The purpose of our study was to understand the training needs of clinicians who do not prescribe PrEP. From September 2017 to January 2018, qualitative interviews were conducted with providers who had no experience prescribing PrEP (N = 20). Thematic analysis revealed four themes: three emphasized the temporal nature of training requirements and one identified training preferences of providers. Study findings suggest that clinicians require specific information in order to integrate PrEP into their practices successfully.

Effect of Internet-Distributed HIV Self-tests on HIV Diagnosis and Behavioral Outcomes in Men Who Have Sex With Men: A Randomized Clinical Trial

IMPORTANCE

Undiagnosed HIV infection results in delayed access to treatment and increased transmission. Self-tests for HIV may increase awareness of infection among men who have sex with men (MSM).

OBJECTIVE

To evaluate the effect of providing HIV self-tests on frequency of testing, diagnoses of HIV infection, and sexual risk behaviors.

DESIGN, SETTING, AND PARTICIPANTS

This 12-month longitudinal, 2-group randomized clinical trial recruited MSM through online banner advertisements from March through August 2015. Those recruited were at least 18 years of age, reported engaging in anal sex with men in the past year, never tested positive for HIV, and were US residents with mailing addresses. Participants completed quarterly online surveys. Telephone call notes and laboratory test results were included in the analysis, which was completed from August 2017 through December 2018.

INTERVENTIONS

All participants had access to online web-based HIV testing resources and telephone counseling on request. Participants were randomized in a 1:1 ratio to the control group or a self-testing (ST) group, which received 4 HIV self-tests after completing the baseline survey with the option to replenish self-tests after completing quarterly surveys. At study completion, all participants were offered 2 self-tests and 1 dried blood spot collection kit.

MAIN OUTCOMES AND MEASURES

Primary outcomes were HIV testing frequency (tested ≥3 times during the trial) and number of newly identified HIV infections among participants in both groups and social network members who used the study HIV self-tests. Secondary outcomes included sex behaviors (eg, anal sex, serosorting).

RESULTS

Of 2665 participants, the mean (SD) age was 30 (9.6) years, 1540 (57.8%) were white, and 443 (16.6%) had never tested for HIV before enrollment. Retention rates at each time point were more than 54%, and 1991 (74.7%) participants initiated 1 or more follow-up surveys. More ST participants reported testing 3 or more times during the trial than control participants (777 of 1014 [76.6%] vs 215 of 977 [22.0%]; P < .01). The cumulative number of newly identified infections during the trial was twice as high in the ST participants as the control participants (25 of 1325 [1.9%] vs 11 of 1340 [0.8%]; P = .02), with the largest difference in HIV infections identified in the first 3 months (12 of 1325 [0.9%] vs 2 of 1340 [0.1%]; P < .01). The ST participants reported 34 newly identified infections among social network members who used the self-tests.

CONCLUSIONS AND RELEVANCE

Distribution of HIV self-tests provides a worthwhile mechanism to increase awareness of HIV infection and prevent transmission among MSM.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02067039.

HIV drug resistance in a cohort of HIV-infected MSM in the United States

OBJECTIVE

To analyze HIV drug resistance among MSM recruited for participation in the HPTN 078 study, which evaluated methods for achieving and maintaining viral suppression in HIV-infected MSM.

METHODS

Individuals were recruited at four study sites in the United States (Atlanta, Georgia; Baltimore, Maryland; Birmingham, Alabama; and Boston, Massachusetts; 2016-2017). HIV genotyping was performed using samples collected at study screening or enrollment. HIV drug resistance was evaluated using the Stanford v8.7 algorithm. A multiassay algorithm was used to identify individuals with recent HIV infection. Clustering of HIV sequences was evaluated using phylogenetic methods.

RESULTS

High-level HIV drug resistance was detected in 44 (31%) of 142 individuals (Atlanta: 21%, Baltimore: 29%, Birmingham: 53%, Boston: 26%); 12% had multiclass resistance, 16% had resistance to tenofovir or emtricitabine, and 8% had resistance to integrase strand transfer inhibitors (INSTIs); 3% had intermediate-level resistance to second-generation INSTIs. In a multivariate model, self-report of ever having been on antiretroviral therapy (ART) was associated with resistance (P = 0.005). One of six recently infected individuals had drug resistance. Phylogenetic analysis identified five clusters of study sequences; two clusters had shared resistance mutations.

CONCLUSION

High prevalence of drug resistance was observed among MSM. Some had multiclass resistance, resistance to drugs used for preexposure prophylaxis (PrEP), and INSTI resistance. These findings highlight the need for improved HIV care in this high-risk population, identification of alternative regimens for PrEP, and inclusion of integrase resistance testing when selecting ART regimens for MSM in the United States.

Development and Calibration of a Dynamic HIV Transmission Model for 6 US Cities

Background. Heterogeneity in HIV microepidemics across US cities necessitates locally oriented, combination implementation strategies to prioritize resources. We calibrated and validated a dynamic, compartmental HIV transmission model to establish a status quo treatment scenario, holding constant current levels of care for 6 US cities. Methods. Built off a comprehensive evidence synthesis, we adapted and extended a previously published model to replicate the transmission, progression, and clinical care for each microepidemic. We identified a common set of 17 calibration targets between 2012 and 2015 and used the Morris method to select the most influential parameters for calibration. We then applied the Nelder-Mead algorithm to iteratively calibrate the model to generate 2000 best-fitting parameter sets. Finally, model projections were internally validated with a series of robustness checks and externally validated against published estimates of HIV incidence, while the face validity of 25-year projections was assessed by a Scientific Advisory Committee (SAC). Results. We documented our process for model development, calibration, and validation to maximize its transparency and reproducibility. The projected outcomes demonstrated a good fit to calibration targets, with a mean goodness-of-fit ranging from 0.0174 (New York City [NYC]) to 0.0861 (Atlanta). Most of the incidence predictions were within the uncertainty range for 5 of the 6 cities (ranging from 21% [Miami] to 100% [NYC]), demonstrating good external validity. The face validity of the long-term projections was confirmed by our SAC, showing that the incidence would decrease or remain stable in Atlanta, Los Angeles, NYC, and Seattle while increasing in Baltimore and Miami. Discussion. This exercise provides a basis for assessing the incremental value of further investments in HIV combination implementation strategies tailored to urban HIV microepidemics.

Natural selection favoring more transmissible HIV detected in United States molecular transmission network

HIV molecular epidemiology can identify clusters of individuals with elevated rates of HIV transmission. These variable transmission rates are primarily driven by host risk behavior; however, the effect of viral traits on variable transmission rates is poorly understood. Viral load, the concentration of HIV in blood, is a heritable viral trait that influences HIV infectiousness and disease progression. Here, we reconstruct HIV genetic transmission clusters using data from the United States National HIV Surveillance System and report that viruses in clusters, inferred to be frequently transmitted, have higher viral loads at diagnosis. Further, viral load is higher in people in larger clusters and with increased network connectivity, suggesting that HIV in the United States is experiencing natural selection to be more infectious and virulent. We also observe a concurrent increase in viral load at diagnosis over the last decade. This evolutionary trajectory may be slowed by prevention strategies prioritized toward rapidly growing transmission clusters.

Vital Signs: Status of Human Immunodeficiency Virus Testing, Viral Suppression, and HIV Preexposure Prophylaxis - United States, 2013-2018

Background

Approximately 38,000 new human immunodeficiency virus (HIV) infections occur in the United States each year; these infections can be prevented. A proposed national initiative, Ending the HIV Epidemic: A Plan for America, incorporates three strategies (diagnose, treat, and prevent HIV infection) and seeks to leverage testing, treatment, and preexposure prophylaxis (PrEP) to reduce new HIV infections in the United States by at least 90% by 2030. Targets to reach this goal include that at least 95% of persons with HIV receive a diagnosis, 95% of persons with diagnosed HIV infection have a suppressed viral load, and 50% of those at increased risk for acquiring HIV are prescribed PrEP. Using surveillance, pharmacy, and other data, CDC determined the current status of these three initiative strategies.

Methods

CDC analyzed HIV surveillance data to estimate annual number of new HIV infections (2013–2017); estimate the percentage of infections that were diagnosed (2017); and determine the percentage of persons with diagnosed HIV infection with viral load suppression (2017). CDC analyzed surveillance, pharmacy, and other data to estimate PrEP coverage, reported as a percentage and calculated as the number of persons who were prescribed PrEP divided by the estimated number of persons with indications for PrEP.

Results

The number of new HIV infections remained stable from 2013 (38,500) to 2017 (37,500) (p = 0.448). In 2017, an estimated 85.8% of infections were diagnosed. Among 854,206 persons with diagnosed HIV infection in 42 jurisdictions with complete reporting of laboratory data, 62.7% had a suppressed viral load. Among an estimated 1.2 million persons with indications for use of PrEP, 18.1% had been prescribed PrEP in 2018.

Conclusion

Accelerated efforts to diagnose, treat, and prevent HIV infection are needed to achieve the U.S. goal of at least 90% reduction in the number of new HIV infections by 2030.

Synthesis and Characterization of Long-Acting Darunavir Prodrugs

Antiretroviral therapy (ART) has improved the quality of life in patients infected with HIV-1. However, complete viral suppression within anatomical compartments remains unattainable. This is complicated by adverse side effects and poor adherence to lifelong therapy leading to the emergence of viral drug resistance. Thus, there is an immediate need for cellular and tissue-targeted long-acting (LA) ART formulations. Herein, we describe two LA prodrug formulations of darunavir (DRV), a potent antiretroviral protease inhibitor. Two classes of DRV prodrugs, M1DRV and M2DRV, were synthesized as lipophilic and hydrophobic prodrugs and stabilized into aqueous suspensions designated NM1DRV and NM2DRV. The formulations demonstrated enhanced intracellular prodrug levels with sustained drug retention and antiretroviral activities for 15 and 30 days compared to native DRV formulation in human monocyte-derived macrophages. Pharmacokinetics tests of NM1DRV and NM2DRV administered to mice demonstrated sustained drug levels in blood and tissues for 30 days. These data, taken together, support the idea that LA DRV with sustained antiretroviral responses through prodrug nanoformulations is achievable.

HIV Risk and Prevention Outcomes in a Probability-Based Sample of Gay and Bisexual Men in the United States

BACKGROUND

Although gay and bisexual men (GBM) represent the largest group of HIV-infected individuals in the United States, nearly all evidence on their HIV risk and prevention outcomes derive from nonprobability samples.

SETTING

A probability-based cohort of GBM (N = 502) from 45 states and Washington, DC.

METHODS

Cross-sectional survey.

RESULTS

Among HIV-negative/unknown/untested GBM, only 6.7% reported using pre-exposure prophylaxis (PrEP) in the past 6 months. Two-thirds (63.3%) of PrEP users reported daily adherence in the past week. Over half (54.2%) of GBM reported not using a condom during anal sex with their most recent male partner; of these men, 93.8% were not on PrEP. Most GBM had been tested for HIV (80.7%) and other sexually transmitted infections (67.1%) in their lifetime, with 45.2% having tested for HIV during the past year. Among those ever tested, 14.1% reported being HIV infected, whereas an additional 8.9% reported testing positive for at least one other sexually transmitted infection after their most recent test. All HIV-positive GBM reported being currently on antiretroviral treatment, and 94.7% reported an undetectable viral load, but nearly one-third (30.4%) reported not taking their medication every day during the past month. A majority of HIV-negative/unknown/untested GBM (64.3%) reported that they had never discussed HIV prevention with their primary health care provider.

CONCLUSIONS

Our findings present a decidedly mixed picture regarding the success of the US National HIV/AIDS Strategy in meeting its stated goals of addressing HIV risk among the general population of GBM.

HIV Pre-Exposure Prophylaxis Implementation Cascade Among Health Care Professionals in the United States: Implications from a Systematic Review and Meta-Analysis

Although pre-exposure prophylaxis (PrEP) has been approved for primary HIV prevention for individuals aged 18 years or older since 2012, PrEP utilization has been suboptimal. To understand trends in PrEP provision from the health care providers' perspective, we systematically assessed each specific stage along the PrEP implementation cascade (i.e., awareness, willingness, consultation, and prescription) among health care professionals (HCPs) in the United States. Between June and December 2018, we conducted a systematic review of published studies on this topic. A total of 36 eligible studies were identified and included in the analyses. Random-effect models were employed to examine the pooled prevalence of each key stage along the cascade. Time trend and subgroup analyses were conducted. A thematic analysis was used to identify barriers and facilitators along the PrEP cascade. In this study, a total of 18,265 HCPs representing diverse demographics were included. The pooled prevalence of PrEP awareness was 68% [95% confidence interval (CI) = 55-80%], willingness to prescribe PrEP was 66% (95% CI = 54-77%), PrEP consultation was 37% (95% CI = 25-51%), and prescription provision was 24% (95% CI = 17-32%). Subgroup analyses revealed that PrEP provision among HCPs was lowest in the south, but has been improving annually nationwide. Infectious disease specialists [odds ratio (OR) = 4.06, 95% CI = 3.12-5.28; compared with primary care providers] and advanced practice registered nurses/physician assistants (OR = 1.51, 95% CI = 1.09-2.09; compared with physicians) had higher odds of prescribing PrEP. Barriers and facilitators regarding optimal PrEP implementation were embedded within individual, dyadic, social, and structural levels. This meta-analysis has comprehensively examined the trend and pattern of PrEP implementation among HCPs. To achieve optimal implementation of the PrEP cascade in the United States, tailored training and programs need to be provided to HCPs.

Ending the Epidemic in America Will Not Happen if the Status Quo Continues: Modeled Projections for Human Immunodeficiency Virus Incidence in 6 US Cities

We estimated 10-year (2020-2030) trajectories for human immunodeficiency virus incidence in 6 US cities. Estimated incidence will only decrease in 2 of 6 cities, with the overall population-weighted incidence decreasing 3.1% (95% credible interval [CrI], -1.0% to 8.5%) by 2025, and 4.3% (95% CrI, -2.6% to 12.7%) by 2030 across cities. Targeted, context-specific combination implementation strategies will be necessary to meet the newly established national targets.

PrEP and sexual well-being: a qualitative study on PrEP, sexuality of MSM, and patient-provider relationships

Most new diagnoses of HIV in the United States are among men who have sex with men (MSM). Pre-exposure prophylaxis (PrEP) is a medication that mitigates risk of HIV acquisition and requires regular STI testing and prescription refills with PrEP providers. Because PrEP care monitors sexual behavior, there is a need to understand how PrEP providers approach sexual health care for MSM patients. In this study, semi-structured qualitative interviews were conducted with 20 MSM in Atlanta, Georgia with current or past prescriptions for PrEP. Data were analyzed with thematic analysis using four major steps: (1) code and codebook development, (2) assigning codes to segments of interviews, (3) code-based and comparative analysis methods, and (4) developing thematic findings. Findings from interviews about changes in sexuality while using PrEP include decreased anxiety surrounding sex, increased feelings of control over personal health, and experiencing less stigma towards sexual partners with HIV. Participants indicated needs for tailored health advice based on individual sexual preferences, sexual health care free from stereotypical assumptions, and improved access to PrEP providers identifying as gay men or who practice in LGBT-friendly settings. Study findings support a call for a gain-frame approach to sexual health in PrEP care for MSM.

Opioid Use Fueling HIV Transmission in an Urban Setting: An Outbreak of HIV Infection Among People Who Inject Drugs-Massachusetts, 2015-2018

Objectives. To describe and control an outbreak of HIV infection among people who inject drugs (PWID).Methods. The investigation included people diagnosed with HIV infection during 2015 to 2018 linked to 2 cities in northeastern Massachusetts epidemiologically or through molecular analysis. Field activities included qualitative interviews regarding service availability and HIV risk behaviors.Results. We identified 129 people meeting the case definition; 116 (90%) reported injection drug use. Molecular surveillance added 36 cases to the outbreak not otherwise linked. The 2 largest molecular groups contained 56 and 23 cases. Most interviewed PWID were homeless. Control measures, including enhanced field epidemiology, syringe services programming, and community outreach, resulted in a significant decline in new HIV diagnoses.Conclusions. We illustrate difficulties with identification and characterization of an outbreak of HIV infection among a population of PWID and the value of an intensive response.Public Health Implications. Responding to and preventing outbreaks requires ongoing surveillance, with timely detection of increases in HIV diagnoses, community partnerships, and coordinated services, all critical to achieving the goal of the national Ending the HIV Epidemic initiative.

Predictors of Failure to Reach Viral Suppression Within 1 Year After Human Immunodeficiency Virus Diagnosis: A Surveillance-Based Analysis

BACKGROUND

Identifying factors associated with poor human immunodeficiency virus (HIV) care continuum outcomes in the first year after HIV diagnosis could guide care engagement efforts at the time of diagnosis.

METHODS

We analyzed data from newly diagnosed persons living with HIV (PLWH) who received a partner services (PS) interview in King County, WA from January 1, 2013, to June 30, 2016. The outcome measure was failure to reach viral suppression, defined as the lack of an HIV RNA result <200 copies/mL reported to surveillance within one year after diagnosis. We constructed Kaplan-Meier curves of time to viral suppression and examined associations between viral suppression and demographic characteristics, substance use, housing status, and plan for HIV care.

RESULTS

Among 549 individuals, 69 (13%) did not achieve viral suppression within 1 year. Failure to reach suppression was associated with having no plan for HIV care at the time of PS interview (n = 72; 13% of the total population; RR, 1.19; 95% CI, 1.04-1.36] and unstable housing (n = 81; 15% of the total population; [RR, 1.19; 95% CI, 1.05-1.35). Among persons with one of these two risk factors, 76% achieved viral suppression, compared with 91% of those with stable housing and a plan for care. Overall, 80% of persons who ultimately reached suppression did so by 7.3 months.

CONCLUSIONS

Providing early support services to PLWH who have unstable housing or no plan for care at the time of HIV partner services interview and to those who do not reach viral suppression shortly after diagnosis could improve the HIV care continuum.

Rectal Microbiome Alterations Associated With Oral Human Immunodeficiency Virus Pre-Exposure Prophylaxis

BACKGROUND

Oral daily tenofovir (TFV) disoproxil fumarate/emtricitabine (TDF/FTC) for human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) is highly effective for HIVprevention, yet long-term effects are not fully understood. We investigated the effects of PrEP on the rectal microbiome in a cohort of men who have sex with men (MSM).

METHODS

This cross-sectional analysis included HIV-negative MSM either on PrEP (n = 37) or not (n = 37) selected from an ongoing cohort using propensity score matching. Rectal swabs were used to examine microbiome composition using 16S ribosomal ribonucleic acid gene sequencing, and associations between PrEP use and microbiota abundance were examined. Hair specimens were used to quantify TFV and FTC exposure over the past 6 weeks on a subset of participants (n = 15).

RESULTS

Pre-exposure prophylaxis use was associated with a significant increase in Streptococcus abundance (adjusted P = .015). Similar associations were identified using least absolute shrinkage and selection operator (LASSO) regression, confirming the increase in Streptococcus and also showing increased Mitsuokella, Fusobacterium, and decreased Escherichia/Shigella. Increased Fusobacterium was significantly associated with increasing TFV exposure.

CONCLUSIONS

Oral TDF/FTC for PrEP is associated with rectal microbiome changes compared to well matched controls, specifically increased Streptococcus and Fusobacterium abundance. This study highlights the need for future investigations of the role of microbiome changes on HIV susceptibility and effectiveness of PrEP.

Viral suppression among persons living with HIV in Trinidad & Tobago: Implications for targeted prevention programmes

In Trinidad and Tobago, despite persons living with HIV (PLHIV) having access to subsidised treatment and care, only 47% PLHIV attain viral suppression. The study assessed the role of individual-level factors on viral suppression among PLHIV in Trinidad and Tobago. Data from 9,629 PLHIV who attended an HIV clinic between 2016 and 2018 were analysed. Cases were aged ≥18 who met the CDC HIV case definition. Viral suppression defined as a viral load of <200 copies/ml at last assessment. The chi-square test of association determined statistically significant relationships between individual factors and viral suppression. Logistic regression was used to estimate odds ratios (OR) for viral suppression. PLHIV who were males (OR = 0.76, 95% CI 0.67-0.87), men who have sex with men (MSM) (OR = 0.82, 95% CI 0.67-0.99), single/unmarried (OR = 0.69, 95% CI 0.55-0.87), aged 18-24 years (OR = 0.66, 95% CI 0.49-0.89), aged 25-49 years (OR = 0.81, 95% CI 0.70-0.94) were less likely to achieve viral suppression. These study findings demonstrate that retention/adherence programmes must urgently identify and target vulnerable PLHIV populations in Trinidad and Tobago to improve viral suppression. Further research examining community and societal factors, such as stigma and discrimination, is warranted.

A longitudinal study assessing differences in causes of death among housed and homeless people diagnosed with HIV in San Francisco

BACKGROUND

San Francisco has implemented several programs addressing the needs of two large vulnerable populations: people living with HIV and those who are homeless. Assessment of these programs on health outcomes is paramount for reducing preventable deaths.

METHODS

Individuals diagnosed with HIV/AIDS and reported to the San Francisco Department of Public Health HIV surveillance registry, ages 13 years or older, who resided in San Francisco at the time of diagnosis, and who died between January 1, 2002, and December 31, 2016 were included in this longitudinal study. The primary independent variable was housing status, dichotomized as ever homeless since diagnosed with HIV, and the dependent variables were disease-specific causes of death, as noted on the death certificate. The Cochran-Armitage test measured changes in the mortality rates over time and unadjusted and adjusted Poisson regression models measured prevalence ratios (PR) and 95% confidence intervals (CI) for causes of death.

RESULTS

A total of 4158 deceased individuals were included in the analyses: the majority were male (87%), ages 40-59 years old at the time of death (64%), non-Hispanic White (60%), men who have sex with men (54%), had an AIDS diagnosis prior to death (87%), and San Francisco residents at the time of death (63%). Compared to those who were housed, those who were homeless were more likely to be younger at time of death, African American, have a history of injecting drugs, female or transgender, and were living below the poverty level (all p values < 0.0001). Among decedents who were SF residents at the time of death, there were declines in the proportion of deaths due to AIDS-defining conditions (p < 0.05) and increases in accidents, cardiomyopathy, heart disease, ischemic disease, non-AIDS cancers, and drug overdoses (p < 0.05). After adjustment, deaths due to mental disorders (aPR = 1.63, 95% CI 1.24, 2.14) were more likely and deaths due to non-AIDS cancers (aPR = 0.63, 95% CI 0.44, 0.89) were less likely among those experiencing homelessness.

CONCLUSIONS

Additional efforts are needed to improve mental health services to homeless people with HIV and prevent mental-health related mortality.

Challenges to eliminating the AIDS pandemic in China

Based on data from the Chinese Center for Disease Control and Prevention (CDC), there were a total of 861,042 people with human immunodeficiency virus (HIV)/ immune deficiency syndrome (AIDS) as of December 31, 2018 in China, a total of 148,589 new HIV infections, and 38,134 AIDS-related deaths in the year 2018. As of 2017, only 74% of people living with HIV knew their status, 80% of people living with HIV were receiving treatment, and 91% were virally suppressed in China. Although mankind has made great progress in the fight against AIDS in recent years, the vision of ending the AIDS epidemic still faces many challenges in China. Due to the huge population and the imbalance in the prevalence of HIV/AIDS in China, expanding HIV screening and early detection remains the key to Chinas response to HIV. Limitations of antiviral therapy (ART), rejection or discontinuation of an immediate ART strategy by people infected with HIV, and the difficult search for a cure for AIDS all limit the coverage and quality of treatment. The high price of drugs and lack of vaccines present enormous challenges; social discrimination still exists, and participation by non-governmental organizations in prevention, treatment, and care is limited. As part of the future response to HIV, HIV eradication programs should continue to be explored, and attention should be paid to long-term care for people living with HIV.

Awareness and uptake of layered HIV prevention programming for young women: analysis of population-based surveys in three DREAMS settings in Kenya and South Africa

Background

The DREAMS Partnership is an ambitious effort to deliver combinations of biomedical, behavioural and structural interventions to reduce HIV incidence among adolescent girls and young women (AGYW). To inform multi-sectoral programming at scale, across diverse settings in Kenya and South Africa, we identified who the programme is reaching, with which interventions and in what combinations.

Methods

Randomly-selected cohorts of 606 AGYW aged 10–14 years and 1081 aged 15–22 years in Nairobi and 2184 AGYW aged 13–22 years in uMkhanyakude, KwaZulu-Natal, were enrolled in 2017, after ~ 1 year of DREAMS implementation. In Gem, western Kenya, population-wide cross-sectional survey data were collected during roll-out in 2016 (n = 1365 AGYW 15–22 years). We summarised awareness and invitation to participate in DREAMS, uptake of interventions categorised by the DREAMS core package, and uptake of a subset of ‘primary’ interventions. We stratified by age-group and setting, and compared across AGYW characteristics.

Results

Awareness of DREAMS was higher among younger women (Nairobi: 89%v78%, aged 15-17v18–22 years; uMkhanyakude: 56%v31%, aged 13-17v18–22; and Gem: 28%v25%, aged 15-17v18–22, respectively).

HIV testing was the most accessed intervention in Nairobi and Gem (77% and 85%, respectively), and school-based HIV prevention in uMkhanyakude (60%). Among those invited, participation in social asset building was > 50%; > 60% accessed ≥2 core package categories, but few accessed all primary interventions intended for their age-group. Parenting programmes and community mobilisation, including those intended for male partners, were accessed infrequently.

In Nairobi and uMkhanyakude, AGYW were more likely to be invited to participate and accessed more categories if they were: aged < 18 years, in school and experienced socio-economic vulnerabilities. Those who had had sex, or a pregnancy, were less likely to be invited to participate but accessed more categories.

Conclusions

In representative population-based samples, awareness and uptake of DREAMS were high after 1 year of implementation. Evidence of ‘layering’ (receiving multiple interventions from the DREAMS core package), particularly among more socio-economically vulnerable AGYW, indicate that intervention packages can be implemented at scale, for intended recipients, in real-world contexts. Challenges remain for higher coverage and greater ‘layering’, including among older, out-of-school AGYW, and community-based programmes for families and men.

Bringing HIV Self-Testing to Scale in the United States: a Review of Challenges, Potential Solutions, and Future Opportunities

HIV self-testing (HIVST) provides an at-home option to counter the barriers that patients face with testing performed in health care settings. HIVST has gradually increased in popularity in a time when social media and technology-based solutions are preferred. In this paper, we consider the aspects of self-testing that merit its integration into HIV testing and prevention systems in the United States. Several elements favor self-testing for large-scale implementation, including ease of use, convenience, potential for integration with mobile health (mHealth), and availability for various modes of distribution. HIVST has a demonstrated ability to reach at-risk individuals who otherwise rarely test. The paradigm of self-testing, however, introduces new challenges, including lesser test performance relative to that in health care settings, nonstandard counseling following receipt of test results, and difficulty in providing linkage to care. After discussing the performance of oral fluid versus blood-based HIVST, we review data regarding acceptability of HIVST, offer insights into counseling and linkage to care for HIVST, and provide examples of novel applications of and future research directions for HIVST.

Evolution of an Electronic Health Record Based-Human Immunodeficiency Virus (HIV) Screening Program in an Urban Emergency Department for Diagnosing Acute and Chronic HIV Infection

BACKGROUND

Since 2006, Centers for Disease Control and Prevention guidelines recommend routine opt-out human immunodeficiency virus (HIV) testing among sexually active 13- to 64-year-olds. Earlier diagnosis and treatment of HIV infection reduces morbidity and mortality and can limit transmission to others.

OBJECTIVE

Our aim was to increase HIV testing, diagnosis, and linkage to care in the emergency department (ED).

METHODS

Beginning May 4, 2015, we utilized our electronic health record (EHR) to enhance HIV testing in patients seen in the Rush University Medical Center emergency department in Chicago, IL, who were 13-64 years of age, did not have HIV listed on their problem list, and did not have an HIV antigen/antibody (Ag/Ab) test in the EHR within the past rolling 12-month period. Strategies included use of a "Best Practice Advisory" and later auto-order screening linked to a complete blood count order.

RESULTS

Our baseline HIV test rate was 2.5% of the target population by age (average of 93 tests per month). From May 4, 2015 to January 31, 2019, 137,749 patients of 240,091 ED visits met our test criteria and 23,588 (17.1% of the target population) HIV Ag/Ab tests were performed, resulting in 164 positive tests. We identified 18 acute seroconverters, 51 new chronically infected persons, and 95 known infected, many of who had not disclosed their status. Our positive test rate was 0.70%, which dropped to 0.29% if only newly diagnosed individuals were counted.

CONCLUSIONS

EHR enhancements in a large urban ED identifies both newly diagnosed acute and chronically HIV-infected persons. Identification of previously diagnosed patients offers an opportunity to relink them to care.

Detection of HIV transmission hotspots in British Columbia, Canada: A novel framework for the prioritization and allocation of treatment and prevention resources

Background

Identifying populations at high risk of HIV transmission is critical for prioritizing treatment and prevention resources and achieving the UNAIDS 90-90-90 Targets.

Methods

HIV transmission rates can be estimated from phylogenetic trees as viral lineage-level diversification rates. To identify HIV-1 transmission foci in British Columbia, Canada, we inferred diversification rates from phylogenetic trees of 36 271 HIV-1 sequences from 9630 anonymized individuals. Diversification rates were combined with sociodemographic and clinical data, then aggregated by patients’ area of residence to predict the distribution of new HIV cases between 2008 and 2018. The predictive power of the model was compared with a phylogenetically uninformed model.

Findings

Aggregated diversification rate measures were predictive of new HIV cases in the subsequent year after adjusting for prevalent and incident cases in the previous year. For every one-unit increase in the mean of the top five diversification rates, the number of new HIV cases increased by on average 1·38-fold (95% CI, 1·28–1·49). In a blind prediction of 2018 cases, diversification rate improved the model's specificity by 12%, accuracy by 9%, top 20 agreement by 100%, and correlation of predicted and observed values by 162% relative to a model that incorporated epidemiological data alone.

Interpretation

By predicting the distribution of future HIV cases, a combined phylogenetic and epidemiological approach identifies hotspots where public health resources are needed most.

Funding

Canadian Institutes of Health Research, University of British Columbia, Public Health Agency of Canada, Genome Canada, Genome BC, Michael Smith Foundation for Health Research, and BC Centre for Excellence in HIV/AIDS.

Trends in Sexual Risk Behaviors Among Hispanic/Latino Men Who Have Sex with Men - 19 Urban Areas, 2011-2017

Correct and consistent condom use and human immunodeficiency virus (HIV) preexposure prophylaxis (PrEP) are protective against sexual transmission of HIV (1,2). The incidence of HIV infection among Hispanic/Latino men who have sex with men (MSM) in the United States is increasing (3). HIV risk among Hispanic/Latino MSM differs based on their place of birth and years of U.S. residence (4). Data from CDC's National HIV Behavioral Surveillance (NHBS)* for 2011-2017 were analyzed to assess changes in sexual risk behaviors among Hispanic/Latino MSM by place of birth and years of U.S. residence. Overall, condomless anal sex during the previous 12 months increased from 63% in 2011 to 74% in 2017, and PrEP use during the previous 12 months increased from 3% in 2014 to 24% in 2017. Regardless of place of birth, nearly 75% of Hispanic/Latino MSM reported condomless anal sex during 2017. However, because of PrEP use, <60% of non-U.S.-born Hispanic/Latino MSM and <50% of U.S.-born Hispanic/Latino MSM reported unprotected anal sex (condomless anal sex and no PrEP use) during 2017. Results indicate that PrEP can be a vital tool for reducing HIV transmission among Hispanic/Latino MSM, especially those who have condomless anal sex. Interventions to prevent HIV acquisition, including increasing PrEP uptake, could address cultural and linguistic needs of Hispanic/Latino MSM, as well as other barriers to prevention of HIV infection typically faced by all MSM.

Surveillance to Monitor the Impact of the Trump Administration on the Health of New York City Residents

CONTEXT

The Trump administration has enacted or proposed many policies that could impact public health. These include attempts to dismantle or repeal the Patient Protection and Affordable Care Act (ACA), restricting funding for women's health care, and loosening of environmental regulations.

OBJECTIVE

To develop a surveillance system to monitor the public health impacts of the Trump administration in New York City.

DESIGN

Epidemiologic assessment. Public health surveillance system.

SETTING

New York City.

PARTICIPANTS

New York City residents.

MAIN OUTCOMES MEASURES

We identified approximately 25 indicators across 5 domains: access to care, food insecurity, reproductive health, environmental health, and general physical and mental health. Sources of data include the New York City Department of Health and Mental Hygiene's (DOHMH's) health and risk behavior telephone survey, vital statistics, emergency department visits, DOHMH sexual health clinics, Federally Qualified Health Centers, lead and diabetes registries, Medicaid claims, Supplementary Nutrition Assistance Program enrollment, Women, Infant, and Children program enrollment, and 311 call records. Data are collected monthly or quarterly where possible. We identified measures to stratify indicators by individual and area-based measures of immigration and poverty.

RESULTS

Since April 2017, we have compiled quarterly reports, including establishing a historical baseline of 10 years to account for secular trends and encompass the establishment and enactment of the ACA. Indicators are interpreted within the context of changes in programming or local policy that might explain trends.

CONCLUSIONS

We have successfully established an adaptive surveillance system that is poised to rapidly detect changes in the health of New York City residents resulting from changes by the Trump administration to public health policy. The development of such systems is a critical function for health departments across the country to play a role in the current political and policy environment.

The PrEP Care Continuum and Black Men Who Have Sex with Men: A Scoping Review of Published Data on Awareness, Uptake, Adherence, and Retention in PrEP Care

Pre-exposure prophylaxis (PrEP) has demonstrated high efficacy to reduce HIV infections, however, racial/ethnic HIV disparities continue among black MSM. The purpose of this review was to assess available data to inform interventions to increase PrEP awareness, uptake, and adherence among black MSM. Of the 3024 studies retrieved, 36 met final inclusion criteria and were categorized into the PrEP care continuum: (1) awareness (n = 16), (2) uptake (n = 9), and (3) adherence (n = 12). Only 26 of the studies presented analytical findings by race/ethnicity. Key barrier themes included cost, HIV-related stigma, and fear of potential side effects. A key facilitator theme identified by black MSM included gaining PrEP awareness from social and sexual networks. There are significant gaps in research on black MSM and PrEP utilization, especially regarding PrEP uptake and adherence. These data are needed to inform interventions to address current inequities in PrEP services, to help improve care outcomes for black MSM.

Implementation of an Immediate HIV Treatment Initiation Program in a Public/Academic Medical Center in the U.S. South: The Miami Test and Treat Rapid Response Program

Test and Rapid Response Treatment (TRRT) linkage programs have demonstrated improved HIV suppression rates. This paper describes the design and implementation of the Miami TRRT initiative and its clinical impact. Assisted by a dedicated care navigator, patients receiving a reactive HIV rapid test at the Florida Department of Health STD Clinic were offered same-day HIV care at the University of Miami/Jackson Memorial Medical Center Adult HIV Outpatient Clinic. Patient retention and labs were tracked for 12 months. Of the 2337 individuals tested, 46 had a reactive HIV test; 41 (89%) consented to participate. For the 36 patients in continued care for a year, 33 (91.7%) achieved virological suppression (< 200 copies/mL) within 70 days of their reactive HIV rapid test; at 12 months, 35 (97.2%) remained suppressed, and mean CD4 T cell counts increased from 452 ± 266 to 597 ± 322 cells/mm³. The Miami TRRT initiative demonstrated that immediate linkage to care is feasible and improves retention and suppression in a public/academic medical center in the U.S. South.

Reducing the African American HIV Disease Burden in the Deep South: Addressing the Role of Faith and Spirituality

Nearly half of HIV infections in the United States are concentrated among African Americans, and over half of new HIV infections occur in the South. African Americans have poorer outcomes in the entire continua of HIV and PrEP care. Complex social, structural, and behavioral factors contribute to our nation's alarming racial disparities in HIV infection, particularly in the Deep South. Despite the importance of faith, spirituality and religious practice in the lives of many African Americans, there has been little scientific investment exploring how African Americans' religious participation, faith and spirituality may impact our nation's HIV epidemic. This article summarizes the state of the science on this critical issue. We also identify opportunities for new scholarship on how faith, spirituality and religious participation may impact HIV care continuum outcomes in the South and call for greater federal research investment on these issues.

A New Perspective on HIV Diagnostics: Reinterpretation in the Age of Early Treatment

Early treatment of HIV infection with antiretroviral therapy in recently identified HIV-infected individuals reduces viral replication and decreases the risk of transmission. The screening and supplemental, confirmatory assays used to identify infection are influenced by early treatment and may obscure a clear diagnosis of HIV infection. In this issue of the Journal of Clinical Microbiology, Manak et al. demonstrate the impact of antiretroviral therapy on the evolution of biomarkers that have traditionally been used for identifying HIV infection (M. M. Manak, L. L. Jagodzinski, A. Shutt, J. A. Malia, et al., J Clin Microbiol 57:e00757-19, 2019, https://doi.org/10.1128/JCM.00757-19).

Octadecyloxyethyl benzyl tenofovir: A novel tenofovir diester provides sustained intracellular levels of tenofovir diphosphate

Pre-exposure prophylaxis (PrEP) with topically or systemically administered antiretroviral agents can prevent acquisition of human immunodeficiency virus type 1 (HIV-1) infection. However, in clinical trials using tenofovir-containing agents, HIV-1 acquisition is reduced but not eliminated. Incomplete adherence remains the major contributor to failure. Sustained release or long-acting antiretroviral agents may provide better HIV-1 protection by reducing the clinical impact of incomplete adherence. To reduce dosing frequency, we synthesized a novel tenofovir prodrug, octadecyloxyethyl benzyl tenofovir (ODE-Bn-TFV), that is designed to release TFV slowly in tissues, and showed potent anti-HIV activity in vitro (EC₅₀ = 1.7 nM). In cells exposed to ¹⁴C labeled TFV, ODE-Bn-TFV or the quickly activated monoester ODE-TFV, rapid cellular uptake for both lipophilic analogs was noted, achieving 50-fold higher levels than unmodified TFV after 48 h. Following exposure to ODE-[8-¹⁴C]TFV, the intracellular diphosphate levels were approximately four-fold higher than with ODE-Bn-TFV. However, intracellular TFVpp drug levels fell rapidly yielding a half-life of about two days. TFVpp levels in ODE-Bn-TFV treated cells decreased much more slowly and reached half-maximal levels in about seven days. These results suggest early accumulation of ODE-Bn-TFV followed by sustained intracellular release following cleavage of the ester bonds linking the ODE and benzyl moieties to the active molecular precursor, thereby potentially allowing for less frequent administration than with more rapidly activated forms of tenofovir.