The Value-of-Information and Value-of-Implementation from Clinical Trials of Diagnostic Tests for HIV-Associated Tuberculosis: A Modeling Analysis.

Objectives. Conventional value-of-information (VOI) analysis assumes complete uptake of an optimal decision. We employed an extended framework that includes value-of-implementation (VOM)-the benefit of encouraging adoption of an optimal strategy-and estimated how future trials of diagnostic tests for HIV-associated tuberculosis could improve public health decision making and clinical and economic outcomes. Methods. We evaluated the clinical outcomes and costs, given current information, of 3 tuberculosis screening strategies among hospitalized people with HIV in South Africa: sputum Xpert (Xpert), sputum Xpert plus urine AlereLAM (Xpert+AlereLAM), and sputum Xpert plus the newer, more sensitive, and costlier urine FujiLAM (Xpert+FujiLAM). We projected the incremental net monetary benefit (INMB) of decision making based on results of a trial comparing mortality with each strategy, rather than decision making based solely on current knowledge of FujiLAM's improved diagnostic performance. We used a validated microsimulation to estimate VOI (the INMB of reducing parameter uncertainty before decision making) and VOM (the INMB of encouraging adoption of an optimal strategy). Results. With current information, adopting Xpert+FujiLAM yields 0.4 additional life-years/person compared with current practices (assumed 50% Xpert and 50% Xpert+AlereLAM). While the decision to adopt this optimal strategy is unaffected by information from the clinical trial (VOI = $ 0 at $3,000/year-of-life saved willingness-to-pay threshold), there is value in scaling up implementation of Xpert+FujiLAM, which results in an INMB (representing VOM) of $650 million over 5 y. Conclusions. Conventional VOI methods account for the value of switching to a new optimal strategy based on trial data but fail to account for the persuasive value of trials in increasing uptake of the optimal strategy. Evaluation of trials should include a focus on their value in reducing barriers to implementation. Highlights: In conventional VOI analysis, it is assumed that the optimal decision will always be adopted even without a trial. This can potentially lead to an underestimation of the value of trials when adoption requires new clinical trial evidence. To capture the influence that a trial may have on decision makers' willingness to adopt the optimal decision, we also consider value-of-implementation (VOM), a metric quantifying the benefit of new study information in promoting wider adoption of the optimal strategy. The overall value-of-a-trial (VOT) includes both VOI and VOM.Our model-based analysis suggests that the information obtained from a trial of screening strategies for HIV-associated tuberculosis in South Africa would have no value, when measured using traditional methods of VOI assessment. A novel strategy, which includes the urine FujiLAM test, is optimal from a health economic standpoint but is underutilized. A trial would reduce uncertainties around downstream health outcomes but likely would not change the optimal decision. The high VOT (nearly $700 million over 5 y) lies solely in promoting uptake of FujiLAM, represented as VOM.Our results highlight the importance of employing a more comprehensive approach for evaluating prospective trials, as conventional VOI methods can vastly underestimate their value. Trialists and funders can and should assess the VOT metric instead when considering trial designs and costs. If VOI is low, the VOM and cost of a trial can be compared with the benefits and costs of other outreach programs to determine the most cost-effective way to improve uptake.

High-risk US International Travelers Seeking Pretravel Consultation During the COVID-19 Pandemic.

Background: To assess the implications of coronavirus disease 2019 (COVID-19)-related travel disruptions, we compared demographics and travel-related circumstances of US travelers seeking pretravel consultation regarding international travel at US Global TravEpiNet (GTEN) sites before and after the initiation of COVID-19 travel warnings. Methods: We analyzed data in the GTEN database regarding traveler demographics and travel-related circumstances with standard questionnaires in the pre-COVID-19 period (January-December 2019) and the COVID-19 period (April 2020-March 2021), excluding travelers from January to March 2020. We conducted descriptive analyses of differences in demographics, travel-related circumstances, routine and travel-related vaccinations, and medications. Results: Compared with 16 903 consultations in the pre-COVID-19 period, only 1564 consultations were recorded at GTEN sites during the COVID-19 period (90% reduction), with a greater proportion of travelers visiting friends and relatives (501/1564 [32%] vs 1525/16 903 [9%]), individuals traveling for >28 days (824/1564 [53%] vs 2522/16 903 [15%]), young children (6 mo-<6 y: 168/1564 [11%] vs 500/16 903 [3%]), and individuals traveling to Africa (1084/1564 [69%] vs 8049/16 903 [48%]). A smaller percentage of vaccine-eligible travelers received vaccines at pretravel consultations during the COVID-19 period than before, except for yellow fever and Japanese encephalitis vaccinations. Conclusions: Compared with the pre-COVID-19 period, a greater proportion of travelers during the COVID-19 period were young children, were planning to visit friends and relatives, were traveling for >28 days, or were traveling to Africa, which are circumstances that contribute to high risk for travel-related infections. Fewer vaccine-eligible travelers were administered travel-related vaccines at pretravel consultations. Counseling and vaccination focused on high-risk international travelers must be prioritized during the COVID-19 pandemic.

Cost-Effectiveness of Long-Acting Injectable HIV Preexposure Prophylaxis in the United States : A Cost-Effectiveness Analysis.

BACKGROUND: The HIV Prevention Trials Network (HPTN) 083 trial demonstrated the superiority of long-acting injectable cabotegravir (CAB-LA) compared with oral emtricitabine-tenofovir disoproxil fumarate (F/TDF) for HIV preexposure prophylaxis (PrEP). OBJECTIVE: To identify the maximum price premium (that is, greatest possible price differential) that society should be willing to accept for the additional benefits of CAB-LA over tenofovir-based PrEP among men who have sex with men and transgender women (MSM/TGW) in the United States. DESIGN: Simulation, cost-effectiveness analysis. DATA SOURCES: Trial and published data, including estimated HIV incidence (5.32, 1.33, and 0.26 per 100 person-years for off PrEP, generic F/TDF and branded emtricitabine-tenofovir alafenamide (F/TAF), and CAB-LA, respectively); 28% 6-year PrEP retention. Annual base-case drug costs: $360 and $16 800 for generic F/TDF and branded F/TAF. Fewer side effects with branded F/TAF versus generic F/TDF were assumed. TARGET POPULATION: 476 700 MSM/TGW at very high risk for HIV (VHR). TIME HORIZON: 10 years. PERSPECTIVE: Health care system. INTERVENTION: CAB-LA versus generic F/TDF or branded F/TAF for HIV PrEP. OUTCOME MEASURES: Primary transmissions, quality-adjusted life-years (QALYs), costs (2020 U.S. dollars), incremental cost-effectiveness ratios (ICERs; U.S. dollars per QALY), maximum price premium for CAB-LA versus tenofovir-based PrEP. RESULTS OF BASE-CASE ANALYSIS: Compared with generic F/TDF (or branded F/TAF), CAB-LA increased life expectancy by 28 000 QALYs (26 000 QALYs) among those at VHR. Branded F/TAF cost more per QALY gained than generic F/TDF compared with no PrEP. At 10 years, CAB-LA could achieve an ICER of at most $100 000 per QALY compared with generic F/TDF at a maximum price premium of $3700 per year over generic F/TDF (CAB-LA price <$4100 per year). RESULTS OF SENSITIVITY ANALYSIS: In a PrEP-eligible population at high risk for HIV, rather than at VHR (n = 1 906 800; off PrEP incidence: 1.54 per 100 person-years), CAB-LA could achieve an ICER of at most $100 000 per QALY versus generic F/TDF at a maximum price premium of $1100 per year over generic F/TDF (CAB-LA price <$1500 per year). LIMITATION: Uncertain clinical and economic benefits of averting future transmissions. CONCLUSION: Effective oral PrEP limits the additional price society should be willing to pay for CAB-LA. PRIMARY FUNDING SOURCE: FHI 360; Eunice Kennedy Shriver National Institute of Child Health and Human Development; National Institute of Allergy and Infectious Diseases; National Heart, Lung, and Blood Institute; National Institute on Drug Abuse; the Reich HIV Scholar Award; and the Steve and Deborah Gorlin MGH Research Scholars Award.

Placental Decidual Arteriopathy and Vascular Endothelial Growth Factor A Expression Among Women With or Without Human Immunodeficiency Virus.

BACKGROUND: Women with human immunodeficiency virus (HIV) (WHIV) are at higher risk of adverse birth outcomes. Proposed mechanisms for the increased risk include placental arteriopathy (vasculopathy) and maternal vascular malperfusion (MVM) due to antiretroviral therapy and medical comorbid conditions. However, these features and their underlying pathophysiologic mechanisms have not been well characterized in WHIV. METHODS: We performed gross and histologic examination and immunohistochemistry staining for vascular endothelial growth factor A (VEGF-A), a key angiogenic factor, on placentas from women with ≥1 MVM risk factors including: weight below the fifth percentile, histologic infarct or distal villous hypoplasia, nevirapine-based antiretroviral therapy, hypertension, and preeclampsia/eclampsia during pregnancy. We compared pathologic characteristics by maternal HIV serostatus. RESULTS: Twenty-seven of 41 (placentas 66%) assessed for VEGF-A were from WHIV. Mean maternal age was 27 years. Among WHIV, median CD4 T-cell count was 440/µL, and the HIV viral load was undetectable in 74%. Of VEGF-A-stained placentas, both decidua and villous endothelium tissue layers were present in 36 (88%). VEGF-A was detected in 31 of 36 (86%) with decidua present, and 39 of 40 (98%) with villous endothelium present. There were no differences in VEGF-A presence in any tissue type by maternal HIV serostatus (P = .28 to >.99). MVM was more common in placentas selected for VEGF-A staining (51 vs 8%; P < .001). CONCLUSIONS: VEGF-A immunostaining was highly prevalent, and staining patterns did not differ by maternal HIV serostatus among those with MVM risk factors, indicating that the role of VEGF-A in placental vasculopathy may not differ by maternal HIV serostatus.

Clinical Outcomes, Costs, and Cost-effectiveness of Strategies for Adults Experiencing Sheltered Homelessness During the COVID-19 Pandemic.

Importance: Approximately 356 000 people stay in homeless shelters nightly in the United States. They have high risk of contracting coronavirus disease 2019 (COVID-19). Objective: To assess the estimated clinical outcomes, costs, and cost-effectiveness associated with strategies for COVID-19 management among adults experiencing sheltered homelessness. Design, Setting, and Participants: This decision analytic model used a simulated cohort of 2258 adults residing in homeless shelters in Boston, Massachusetts. Cohort characteristics and costs were adapted from Boston Health Care for the Homeless Program. Disease progression, transmission, and outcomes data were taken from published literature and national databases. Surging, growing, and slowing epidemics (effective reproduction numbers [Re], 2.6, 1.3, and 0.9, respectively) were examined. Costs were from a health care sector perspective, and the time horizon was 4 months, from April to August 2020. Exposures: Daily symptom screening with polymerase chain reaction (PCR) testing of individuals with positive symptom screening results, universal PCR testing every 2 weeks, hospital-based COVID-19 care, alternative care sites (ACSs) for mild or moderate COVID-19, and temporary housing were each compared with no intervention. Main Outcomes and Measures: Cumulative infections and hospital-days, costs to the health care sector (US dollars), and cost-effectiveness, as incremental cost per case of COVID-19 prevented. Results: The simulated population of 2258 sheltered homeless adults had a mean (SD) age of 42.6 (9.04) years. Compared with no intervention, daily symptom screening with ACSs for pending tests or confirmed COVID-19 and mild or moderate disease was associated with 37% fewer infections (1954 vs 1239) and 46% lower costs ($6.10 million vs $3.27 million) at an Re of 2.6, 75% fewer infections (538 vs 137) and 72% lower costs ($1.46 million vs $0.41 million) at an Re of 1.3, and 51% fewer infections (174 vs 85) and 51% lower costs ($0.54 million vs $0.26 million) at an Re of 0.9. Adding PCR testing every 2 weeks was associated with a further decrease in infections; incremental cost per case prevented was $1000 at an Re of 2.6, $27 000 at an Re of 1.3, and $71 000 at an Re of 0.9. Temporary housing with PCR every 2 weeks was most effective but substantially more expensive than other options. Compared with no intervention, temporary housing with PCR every 2 weeks was associated with 81% fewer infections (376) and 542% higher costs ($39.12 million) at an Re of 2.6, 82% fewer infections (95) and 2568% higher costs ($38.97 million) at an Re of 1.3, and 59% fewer infections (71) and 7114% higher costs ($38.94 million) at an Re of 0.9. Results were sensitive to cost and sensitivity of PCR and ACS efficacy in preventing transmission. Conclusions and Relevance: In this modeling study of simulated adults living in homeless shelters, daily symptom screening and ACSs were associated with fewer severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and decreased costs compared with no intervention. In a modeled surging epidemic, adding universal PCR testing every 2 weeks was associated with further decrease in SARS-CoV-2 infections at modest incremental cost and should be considered during future surges.

Brief Report: Chronic Placental Inflammation Among Women Living With HIV in Uganda.

BACKGROUND: HIV-exposed, uninfected (HEU) children have poorer early-life outcomes than HIV-unexposed children. The determinants of adverse health outcomes among HEU children are poorly understood but may result from chronic placental inflammation (CPI). SETTING AND METHODS: We enrolled 176 pregnant women living with HIV (WLWH) taking antiretroviral therapy in southwestern Uganda and 176 HIV-uninfected women to compare CPI prevalence by maternal HIV serostatus. Placentas were evaluated histologically by an expert pathologist for presence of CPI, defined as chronic chorioamnionitis, plasma cell deciduitis, villitis of unknown etiology, or chronic histiocytic intervillositis. Placentas with CPI were additionally immunostained with CD3 (T cell), CD20 (B cell), and CD68 (macrophage) markers to characterize inflammatory cell profiles. RESULTS: WLWH and HIV-uninfected women had similar age, parity, and gestational age. Among WLWH, the mean CD4 count was 480 cells/µL, and 74% had an undetectable HIV viral load. We detected CPI in 16 (9%) placentas from WLWH and 24 (14%) from HIV-uninfected women (P = 0.18). Among WLWH, CPI was not associated with the CD4 count or HIV viral load. Villitis of unknown etiology was twice as common among HIV-uninfected women than WLWH (10 vs. 5%, P = 0.04). Among placentas with CPI, more villous inflammatory cells stained for CD3 or CD68 among HIV-uninfected women than WLWH (79% vs. 46%, P = 0.07). CONCLUSIONS: CPI prevalence did not differ by HIV serostatus. T-cell (CD3) and macrophage (CD68) markers were more prevalent in placental inflammatory cells from HIV-uninfected women. Our results do not support CPI as a leading mechanism for poor outcomes among HEU children in the antiretroviral therapy era.

Clinical Outcomes, Costs, and Cost-effectiveness of Strategies for People Experiencing Sheltered Homelessness During the COVID-19 Pandemic.

IMPORTANCE: Approximately 356,000 people stay in homeless shelters nightly in the US. They are at high risk for COVID-19. OBJECTIVE: To assess clinical outcomes, costs, and cost-effectiveness of strategies for COVID-19 management among sheltered homeless adults. DESIGN: We developed a dynamic microsimulation model of COVID-19 in sheltered homeless adults in Boston, Massachusetts. We used cohort characteristics and costs from Boston Health Care for the Homeless Program. Disease progression, transmission, and outcomes data were from published literature and national databases. We examined surging, growing, and slowing epidemics (effective reproduction numbers [Re] 2.6, 1.3, and 0.9). Costs were from a health care sector perspective; time horizon was 4 months, from April to August 2020. SETTING & PARTICIPANTS: Simulated cohort of 2,258 adults residing in homeless shelters in Boston. INTERVENTIONS: We assessed daily symptom screening with polymerase chain reaction (PCR) testing of screen-positives, universal PCR testing every 2 weeks, hospital-based COVID-19 care, alternate care sites [ACSs] for mild/moderate COVID-19, and temporary housing, each compared to no intervention. MAIN OUTCOMES AND MEASURES: Cumulative infections and hospital-days, costs to the health care sector (US dollars), and cost-effectiveness, as incremental cost per case prevented of COVID-19. RESULTS: We simulated a population of 2,258 sheltered homeless adults with mean age of 42.6 years. Compared to no intervention, daily symptom screening with ACSs for pending tests or confirmed COVID-19 and mild/moderate disease led to 37% fewer infections and 46% lower costs (Re=2.6), 75% fewer infections and 72% lower costs (Re=1.3), and 51% fewer infections and 51% lower costs (Re=0.9). Adding PCR testing every 2 weeks further decreased infections; incremental cost per case prevented was $1,000 (Re=2.6), $27,000 (Re=1.3), and $71,000 (Re=0.9). Temporary housing with PCR every 2 weeks was most effective but substantially more costly than other options. Results were sensitive to cost and sensitivity of PCR and ACS efficacy in preventing transmission. CONCLUSIONS & RELEVANCE: In this modeling study of simulated adults living in homeless shelters, daily symptom screening and ACSs were associated with fewer COVID-19 infections and decreased costs compared with no intervention. In a modeled surging epidemic, adding universal PCR testing every 2 weeks was associated with further decrease in COVID-19 infections at modest incremental cost and should be considered during future surges.