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BACKGROUND: Success in conducting clinical trials during the coronavirus disease of 2019 pandemic requires the ability to innovate and adapt. There are well-established procedures for the blinding of investigational agents, especially medications, in placebo-controlled randomized clinical trials within the Veterans Health Administration. However, these procedures, managed by research pharmacists, may not apply to investigational agents that are not exclusively managed by pharmacy, such as blood products, including coronavirus disease of 2019 convalescent plasma (plasma). In the absence of established blinding procedures, such studies require special design considerations to minimize uncertainty or bias. METHODS: We describe the processes and procedures developed for blinding of plasma in "Veterans Affairs CoronavirUs Research and Efficacy Studies-1" as a prototypical study using this class of investigational therapeutic agents. Veterans Affairs CoronavirUs Research and Efficacy Studies-1 is an ongoing multicenter randomized clinical trial testing the efficacy of plasma added to conventional therapy for severe acute respiratory syndrome coronavirus-2 infection. RESULTS: We report the design of procedures to supply investigational blood products or 0.9% normal saline (saline) control while ensuring the integrity of the blind. Key aspects include workflow considerations, physical blinding strategies, and methods for engaging stakeholders. These procedures leverage the well-established Veterans Affairs research pharmacist's research infrastructure, and Blood Bank Services, which is responsible for blood-based investigational products. CONCLUSION: By describing the methods used to deliver blood products in a blinded manner in Veterans Affairs CoronavirUs Research and Efficacy Studies-1, we strive both to educate and to increase awareness to improve the implementation of these biological therapeutics for future, high-quality research studies.
Subject(s)
COVID-19 , Veterans , COVID-19/therapy , Humans , Immunization, Passive , Pandemics , Pharmaceutical Preparations , SARS-CoV-2 , Treatment Outcome , COVID-19 SerotherapyABSTRACT
Importance: Selecting effective antidepressants for the treatment of major depressive disorder (MDD) is an imprecise practice, with remission rates of about 30% at the initial treatment. Objective: To determine whether pharmacogenomic testing affects antidepressant medication selection and whether such testing leads to better clinical outcomes. Design, Setting, and Participants: A pragmatic, randomized clinical trial that compared treatment guided by pharmacogenomic testing vs usual care. Participants included 676 clinicians and 1944 patients. Participants were enrolled from 22 Department of Veterans Affairs medical centers from July 2017 through February 2021, with follow-up ending November 2021. Eligible patients were those with MDD who were initiating or switching treatment with a single antidepressant. Exclusion criteria included an active substance use disorder, mania, psychosis, or concurrent treatment with a specified list of medications. Interventions: Results from a commercial pharmacogenomic test were given to clinicians in the pharmacogenomic-guided group (n = 966). The comparison group received usual care and access to pharmacogenomic results after 24 weeks (n = 978). Main Outcomes and Measures: The co-primary outcomes were the proportion of prescriptions with a predicted drug-gene interaction written in the 30 days after randomization and remission of depressive symptoms as measured by the Patient Health Questionnaire-9 (PHQ-9) (remission was defined as PHQ-9 ≤ 5). Remission was analyzed as a repeated measure across 24 weeks by blinded raters. Results: Among 1944 patients who were randomized (mean age, 48 years; 491 women [25%]), 1541 (79%) completed the 24-week assessment. The estimated risks for receiving an antidepressant with none, moderate, and substantial drug-gene interactions for the pharmacogenomic-guided group were 59.3%, 30.0%, and 10.7% compared with 25.7%, 54.6%, and 19.7% in the usual care group. The pharmacogenomic-guided group was more likely to receive a medication with a lower potential drug-gene interaction for no drug-gene vs moderate/substantial interaction (odds ratio [OR], 4.32 [95% CI, 3.47 to 5.39]; P < .001) and no/moderate vs substantial interaction (OR, 2.08 [95% CI, 1.52 to 2.84]; P = .005) (P < .001 for overall comparison). Remission rates over 24 weeks were higher among patients whose care was guided by pharmacogenomic testing than those in usual care (OR, 1.28 [95% CI, 1.05 to 1.57]; P = .02; risk difference, 2.8% [95% CI, 0.6% to 5.1%]) but were not significantly higher at week 24 when 130 patients in the pharmacogenomic-guided group and 126 patients in the usual care group were in remission (estimated risk difference, 1.5% [95% CI, -2.4% to 5.3%]; P = .45). Conclusions and Relevance: Among patients with MDD, provision of pharmacogenomic testing for drug-gene interactions reduced prescription of medications with predicted drug-gene interactions compared with usual care. Provision of test results had small nonpersistent effects on symptom remission. Trial Registration: ClinicalTrials.gov Identifier: NCT03170362.
Subject(s)
Antidepressive Agents , Depressive Disorder, Major , Drug Interactions , Inappropriate Prescribing , Pharmacogenomic Testing , Antidepressive Agents/metabolism , Antidepressive Agents/pharmacology , Antidepressive Agents/therapeutic use , Clinical Decision-Making , Depressive Disorder, Major/drug therapy , Depressive Disorder, Major/genetics , Drug Interactions/genetics , Female , Humans , Inappropriate Prescribing/prevention & control , Male , Middle Aged , Pharmacogenetics , Remission Induction , Treatment Outcome , United States , United States Department of Veterans AffairsABSTRACT
BACKGROUND: In randomized trials, prazosin, an α1-adrenoreceptor antagonist, has been effective in alleviating nightmares associated with post-traumatic stress disorder (PTSD) in military veterans. METHODS: We recruited veterans from 13 Department of Veterans Affairs medical centers who had chronic PTSD and reported frequent nightmares. Participants were randomly assigned to receive prazosin or placebo for 26 weeks; the drug or placebo was administered in escalating divided doses over the course of 5 weeks to a daily maximum of 20 mg in men and 12 mg in women. After week 10, participants continued to receive prazosin or placebo in a double-blind fashion for an additional 16 weeks. The three primary outcome measures were the change in score from baseline to 10 weeks on the Clinician-Administered PTSD Scale (CAPS) item B2 ("recurrent distressing dreams"; scores range from 0 to 8, with higher scores indicating more frequent and more distressing dreams); the change in score from baseline to 10 weeks on the Pittsburgh Sleep Quality Index (PSQI; scores range from 0 to 21, with higher scores indicating worse sleep quality); and the Clinical Global Impression of Change (CGIC) score at 10 weeks (scores range from 1 to 7, with lower scores indicating greater improvement and a score of 4 indicating no change). RESULTS: A total of 304 participants underwent randomization; 152 were assigned to prazosin, and 152 to placebo. At 10 weeks, there were no significant differences between the prazosin group and the placebo group in the mean change from baseline in the CAPS item B2 score (between-group difference, 0.2; 95% confidence interval [CI], -0.3 to 0.8; P=0.38), in the mean change in PSQI score (between-group difference, 0.1; 95% CI, -0.9 to 1.1; P=0.80), or in the CGIC score (between-group difference, 0; 95% CI, -0.3 to 0.3; P=0.96). There were no significant differences in these measures at 26 weeks (a secondary outcome) or in other secondary outcomes. At 10 weeks, the mean difference between the prazosin group and the placebo group in the change from baseline in supine systolic blood pressure was a decrease of 6.7 mm Hg. The adverse event of new or worsening suicidal ideation occurred in 8% of the participants assigned to prazosin versus 15% of those assigned to placebo. CONCLUSIONS: In this trial involving military veterans who had chronic PTSD, prazosin did not alleviate distressing dreams or improve sleep quality. (Funded by the Department of Veterans Affairs Cooperative Studies Program; PACT ClinicalTrials.gov number, NCT00532493 .).
Subject(s)
Adrenergic alpha-1 Receptor Antagonists/administration & dosage , Dreams/drug effects , Prazosin/administration & dosage , Sleep Wake Disorders/drug therapy , Stress Disorders, Post-Traumatic/drug therapy , Veterans , Adrenergic alpha-1 Receptor Antagonists/adverse effects , Adult , Combined Modality Therapy , Dose-Response Relationship, Drug , Double-Blind Method , Female , Hospitals, Veterans , Humans , Male , Middle Aged , Prazosin/adverse effects , Psychiatric Status Rating Scales , Psychotherapy , Sleep/drug effects , Stress Disorders, Post-Traumatic/psychology , Stress Disorders, Post-Traumatic/therapy , Suicidal Ideation , Treatment Failure , United StatesABSTRACT
BACKGROUND: To describe an automated method for assessment of the plausibility of continuous variables collected in the electronic health record (EHR) data for real world evidence research use. METHODS: The most widely used approach in quality assessment (QA) for continuous variables is to detect the implausible numbers using prespecified thresholds. In augmentation to the thresholding method, we developed a score-based method that leverages the longitudinal characteristics of EHR data for detection of the observations inconsistent with the history of a patient. The method was applied to the height and weight data in the EHR from the Million Veteran Program Data from the Veteran's Healthcare Administration (VHA). A validation study was also conducted. RESULTS: The receiver operating characteristic (ROC) metrics of the developed method outperforms the widely used thresholding method. It is also demonstrated that different quality assessment methods have a non-ignorable impact on the body mass index (BMI) classification calculated from height and weight data in the VHA's database. CONCLUSIONS: The score-based method enables automated and scaled detection of the problematic data points in health care big data while allowing the investigators to select the high-quality data based on their need. Leveraging the longitudinal characteristics in EHR will significantly improve the QA performance.
Subject(s)
Electronic Health Records , Veterans , Big Data , Data Accuracy , Data Management , HumansABSTRACT
BACKGROUND: Few studies have examined the efficacy of drug-eluting stents (DES) for reducing aortocoronary saphenous vein bypass graft (SVG) failure compared with bare-metal stents (BMS) in patients undergoing stenting of de-novo SVG lesions. We assessed the risks and benefits of the use of DES versus BMS in de-novo SVG lesions. METHODS: Patients were recruited to our double-blind, randomised controlled trial from 25 US Department of Veterans Affairs centres. Eligible participants were aged at least 18 years and had at least one significant de-novo SVG lesion (50-99% stenosis of a 2·25-4·5 mm diameter SVG) requiring percutaneous coronary intervention with intent to use embolic protection devices. Enrolled patients were randomly assigned, in a 1:1 ratio, by phone randomisation system to receive a DES or BMS. Randomisation was stratified by presence or absence of diabetes and number of target SVG lesions requiring percutaneous coronary intervention (one or two or more) within each participating site by use of an adaptive scheme intended to balance the two stent type groups on marginal totals for the stratification factors. Patients, referring physicians, study coordinators, and outcome assessors were masked to group allocation. The primary endpoint was the 12-month incidence of target vessel failure, defined as the composite of cardiac death, target vessel myocardial infarction, or target vessel revascularisation. The DIVA trial is registered with ClinicalTrials.gov, number NCT01121224. FINDINGS: Between Jan 1, 2012, and Dec 31, 2015, 599 patients were randomly assigned to the stent groups, and the data for 597 patients were used. The patients' mean age was 68·6 (SD 7·6) years, and 595 (>99%) patients were men. The two stent groups were similar for most baseline characteristics. At 12 months, the incidence of target vessel failure was 17% (51 of 292) in the DES group versus 19% (58 of 305) in the BMS group (adjusted hazard ratio 0·92, 95% CI 0·63-1·34, p=0·70). Between-group differences in the components of the primary endpoint, serious adverse events, or stent thrombosis were not significant. Enrolment was stopped before the revised target sample size of 762 patients was reached. INTERPRETATION: In patients undergoing stenting of de-novo SVG lesions, no significant differences in outcomes between those receiving DES and BMS during 12 months of follow-up were found. The study results have important economic implications in countries with high DES prices such as the USA, because they suggest that the lower-cost BMS can be used in SVG lesions without compromising either safety or efficacy. FUNDING: US Department of Veterans Affairs Cooperative Studies Program.
Subject(s)
Graft Rejection/drug therapy , Percutaneous Coronary Intervention/instrumentation , Saphenous Vein/surgery , Thrombosis/epidemiology , Aged , Double-Blind Method , Drug-Eluting Stents , Female , Humans , Male , Middle Aged , Self Expandable Metallic Stents , Thrombosis/etiology , Treatment OutcomeABSTRACT
We review adaptive designs for clinical trials, giving special attention to the control of the Type I error in late-phase confirmatory trials, when the trial planner wishes to adjust the final sample size of the study in response to an unblinded analysis of interim estimates of treatment effects. We point out that there is considerable inefficiency in using the adaptive designs that employ conditional power calculations to reestimate the sample size and that maintain the Type I error by using certain weighted test statistics. Although these adaptive designs have little advantage over familiar group-sequential designs, our review also describes recent developments in adaptive designs that are both flexible and efficient. We also discuss the use of Bayesian designs, when the context of use demands control over operating characteristics (Type I and II errors) and correction of the bias of estimated treatment effects.
Subject(s)
Bias , Clinical Trials as Topic , Data Interpretation, Statistical , Research Design , Sample Size , Bayes Theorem , Humans , Models, StatisticalABSTRACT
The Omicron SARS-CoV-2 variant continues to strain healthcare systems. Developing tools that facilitate the identification of patients at highest risk of adverse outcomes is a priority. The study objectives are to develop population-scale predictive models that: 1) identify predictors of adverse outcomes with Omicron surge SARS-CoV-2 infections, and 2) predict the impact of prioritized vaccination of high-risk groups for said outcome. We prepared a retrospective longitudinal observational study of a national cohort of 172,814 patients in the U.S. Veteran Health Administration who tested positive for SARS-CoV-2 from January 15 to August 15, 2022. We utilized sociodemographic characteristics, comorbidities, and vaccination status, at time of testing positive for SARS-CoV-2 to predict hospitalization, escalation of care (high-flow oxygen, mechanical ventilation, vasopressor use, dialysis, or extracorporeal membrane oxygenation), and death within 30 days. Machine learning models demonstrated that advanced age, high comorbidity burden, lower body mass index, unvaccinated status, and oral anticoagulant use were the important predictors of hospitalization and escalation of care. Similar factors predicted death. However, anticoagulant use did not predict mortality risk. The all-cause death model showed the highest discrimination (Area Under the Curve (AUC) = 0.903, 95% Confidence Interval (CI): 0.895, 0.911) followed by hospitalization (AUC = 0.822, CI: 0.818, 0.826), then escalation of care (AUC = 0.793, CI: 0.784, 0.805). Assuming a vaccine efficacy range of 70.8 to 78.7%, our simulations projected that targeted prevention in the highest risk group may have reduced 30-day hospitalization and death in more than 2 of 5 unvaccinated patients.
Subject(s)
COVID-19 , Hospitalization , Machine Learning , SARS-CoV-2 , Humans , COVID-19/epidemiology , COVID-19/mortality , COVID-19/virology , Male , Female , Aged , Middle Aged , SARS-CoV-2/isolation & purification , Retrospective Studies , Hospitalization/statistics & numerical data , Longitudinal Studies , Comorbidity , COVID-19 Vaccines/administration & dosage , Aged, 80 and over , Vaccination , AdultABSTRACT
Affecting an estimated 88 million Americans, prediabetes increases the risk for developing type 2 diabetes mellitus (T2DM), and independently, cardiovascular disease, retinopathy, nephropathy, and neuropathy. Nevertheless, little is known about the use of metformin for diabetes prevention among patients in the Veterans Health Administration, the largest integrated healthcare system in the U.S. This is a retrospective observational cohort study of the proportion of Veterans with incident prediabetes who were prescribed metformin at the Veterans Health Administration from October 2010 to September 2019. Among 1,059,605 Veterans with incident prediabetes, 12,009 (1.1%) were prescribed metformin during an average 3.4 years of observation after diagnosis. Metformin prescribing was marginally higher (1.6%) among those with body mass index (BMI) ≥35 kg/m2, age <60 years, HbA1c≥6.0%, or those with a history of gestational diabetes, all subgroups at a higher risk for progression to T2DM. In a multivariable model, metformin was more likely to be prescribed for those with BMI ≥35 kg/m2 incidence rate ratio [IRR] 2.6 [95% confidence intervals (CI): 2.1-3.3], female sex IRR, 2.4 [95% CI: 1.8-3.3], HbA1c≥6% IRR, 1.93 [95% CI: 1.5-2.4], age <60 years IRR, 1.7 [95% CI: 1.3-2.3], hypertriglyceridemia IRR, 1.5 [95% CI: 1.2-1.9], hypertension IRR, 1.5 [95% CI: 1.1-2.1], Major Depressive Disorder IRR, 1.5 [95% CI: 1.1-2.0], or schizophrenia IRR, 2.1 [95% CI: 1.2-3.8]. Over 20% of Veterans with prediabetes attended a comprehensive structured lifestyle modification clinic or program. Among Veterans with prediabetes, metformin was prescribed to 1.1% overall, a proportion that marginally increased to 1.6% in the subset of individuals at highest risk for progression to T2DM.
Subject(s)
Depressive Disorder, Major , Diabetes Mellitus, Type 2 , Metformin , Prediabetic State , Veterans , Female , Humans , Middle Aged , Cohort Studies , Depressive Disorder, Major/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/diagnosis , Hypoglycemic Agents/therapeutic use , Metformin/therapeutic use , Prediabetic State/drug therapy , Prediabetic State/epidemiology , Prescriptions , Retrospective StudiesABSTRACT
Introduction and Objective: Continuous glucose monitoring (CGM) can improve glycemic control in people with diabetes on insulin therapy. We assessed rates of prescriptions for CGM in a national sample of Veterans across subgroups defined by race and ethnicity. Methods: This cross-sectional analysis of data from the U.S. Veterans Health Administration included adults with type 1 or type 2 diabetes on insulin therapy. Main exposures included self-reported race and ethnicity, and primary outcome was the percentage of patients with at least one CGM prescription between January 1, 2020, and December 31, 2021. Association of race and ethnicity categories with CGM prescription was examined using multilevel, multivariable mixed-effects models. Results: Among 368,794 patients on insulin (mean age, 68.5 years; 96% male; 96.8% type 2 diabetes; 0.8% American Indian or Alaska Native, 0.7% Asian, 18.9% Black or African American, 0.9% Native Hawaiian or other Pacific Islander, 70.2% White, 2.8% multiracial, 5.7% with unknown race, and 7.0% Hispanic or Latino ethnicity), 11.2% were prescribed CGM. CGM was prescribed for 10.4% American Indian or Alaska Native, 9.7% Asian, 9.2% Black or African American, 9.3% Native Hawaiian or other Pacific Islander, 11.8% White, 11.8% multiracial, and 10.1% patients with unknown race. CGM was prescribed for 8.3% Hispanic or Latino, 11.4% non-Hispanic, and 11.5% of patients with unknown ethnicity. After accounting for patient-, clinical-, and system-level factors, Black or African American patients had significantly lower odds of CGM prescription compared with White patients (adjusted odds ratio [aOR] 0.62, 95% confidence interval [CI] 0.59-0.64), whereas Hispanic or Latino patients had significantly lower odds compared with non-Hispanic patients (aOR 0.79, 95% CI 0.74-0.84). Findings were consistent across subgroups with clinical indications for CGM use. Conclusions: Among Veterans with diabetes on insulin therapy, there were significant disparities in prescribing of CGM technology by race and ethnicity, which require further study and intervention.
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BACKGROUND: Warfarin anticoagulation reduces thromboembolic complications in patients with atrial fibrillation or mechanical heart valves, but effective management is complex, and the international normalized ratio (INR) is often outside the target range. As compared with venous plasma testing, point-of-care INR measuring devices allow greater testing frequency and patient involvement and may improve clinical outcomes. METHODS: We randomly assigned 2922 patients who were taking warfarin because of mechanical heart valves or atrial fibrillation and who were competent in the use of point-of-care INR devices to either weekly self-testing at home or monthly high-quality testing in a clinic. The primary end point was the time to a first major event (stroke, major bleeding episode, or death). RESULTS: The patients were followed for 2.0 to 4.75 years, for a total of 8730 patient-years of follow-up. The time to the first primary event was not significantly longer in the self-testing group than in the clinic-testing group (hazard ratio, 0.88; 95% confidence interval, 0.75 to 1.04; P=0.14). The two groups had similar rates of clinical outcomes except that the self-testing group reported more minor bleeding episodes. Over the entire follow-up period, the self-testing group had a small but significant improvement in the percentage of time during which the INR was within the target range (absolute difference between groups, 3.8 percentage points; P<0.001). At 2 years of follow-up, the self-testing group also had a small but significant improvement in patient satisfaction with anticoagulation therapy (P=0.002) and quality of life (P<0.001). CONCLUSIONS: As compared with monthly high-quality clinic testing, weekly self-testing did not delay the time to a first stroke, major bleeding episode, or death to the extent suggested by prior studies. These results do not support the superiority of self-testing over clinic testing in reducing the risk of stroke, major bleeding episode, and death among patients taking warfarin therapy. (Funded by the Department of Veterans Affairs Cooperative Studies Program; ClinicalTrials.gov number, NCT00032591.).
Subject(s)
Anticoagulants/therapeutic use , Drug Monitoring/methods , International Normalized Ratio , Self Care , Warfarin/therapeutic use , Aged , Anticoagulants/adverse effects , Atrial Fibrillation/drug therapy , Female , Follow-Up Studies , Heart Valve Prosthesis , Hemorrhage/epidemiology , Hemorrhage/prevention & control , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Mortality , Myocardial Infarction/epidemiology , Prospective Studies , Stroke/epidemiology , Stroke/prevention & control , Thrombosis/prevention & control , Warfarin/adverse effectsABSTRACT
Background: Effective therapeutics for severe acute respiratory syndrome CoronaVirus-2 (SARS-CoV-2) infection are evolving. Under Emergency Use Authorization, COVID-19 convalescent plasma (CCP) was widely used in individuals hospitalized for COVID-19, but few randomized controlled trials supported its efficacy to limit respiratory failure or death. Methods: VA CoronavirUs Research and Efficacy Studies-1 (VA CURES-1) was a double-blind, multi-site, placebo-controlled, randomized clinical trial evaluating the efficacy and safety of CCP with conventional therapy in hospitalized Veterans with SARS-CoV-2 infection and early respiratory compromise (requirement for oxygen). Participants (planned sample size 702) were randomized 1:1 to receive CCP with high titer neutralizing activity or 0.9% saline, stratified by site and age (≥65 versus <65 years old). Participants were followed daily during initial hospitalization and at Days 15, 22 and 28. Outcomes: The composite primary outcome was acute hypoxemic respiratory failure or all-cause death by Day 28. Secondary outcomes by day 28 included time-to-recovery, clinical severity, mortality, rehospitalization for COVID-19, and adverse events. Serial respiratory and blood samples were collected for safety, virologic and immunologic analyses and future studies. Key variables in predicting the success of CURES-1 were: (1) enrollment early in the course of severe infection; (2) use of plasma with high neutralizing activity; (3) reliance on unambiguous, clinically meaningful outcomes. CURES-1 was terminated for futility due to perceived inability to enroll in the lull between the Alpha and Delta waves of the SARS CoV-2 epidemic. Conclusions: VA CURES-1 was a large multi-site trial designed to provide conclusive information about the efficacy of CCP in well-characterized patients at risk for progression of COVID-19. It utilized a rigorous study design with relevant initial timing, quality of product and outcomes. Trial registration: ClinicalTrials.gov Identifier: NCT04539275.
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BACKGROUND: Chronic low back pain (cLBP) is a common and highly disabling problem world-wide. Although many treatment options exist, it is unclear how to best sequence the multitude of care options to provide the greatest benefit to patients. METHODS: The Sequential and Comparative Evaluation of Pain Treatment Effectiveness Response (SCEPTER) trial uses a pragmatic, randomized, stepped design. Enrollment targets 2529 participants from 20 Veterans Affairs (VA) medical centers. Participants with chronic low back pain will first be randomized to one of three options: 1) an internet-based self-management program (Pain EASE); 2) a tailored physical therapy program (Enhanced PT); or 3) continued care with active monitoring (CCAM), a form of usual care. Participants not achieving a 30% or 2-point reduction on the study's primary outcome (Brief Pain Inventory Pain Interference (BPI-PI) subscale), 3 months after beginning treatment may undergo re-randomization in a second step to cognitive behavioral therapy for chronic pain, spinal manipulation therapy, or yoga. Secondary outcomes include pain intensity, back pain-related disability, depression, and others. Participants will be assessed every three months until 12 months after initiating their final trial therapy. Companion economic and implementation analyses are also planned. RESULTS: The SCEPTER trial is currently recruiting and enrolling participants. CONCLUSIONS: Trial results will inform treatment decisions for the stepped management of chronic low back pain - a common and disabling condition. Additional analyses will help tailor treatment selection to individual patient characteristics, promote efficient resource use, and identify implementation barriers of interventions. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT04142177.
Subject(s)
Chronic Pain , Cognitive Behavioral Therapy , Low Back Pain , Humans , Back Pain , Chronic Pain/therapy , Chronic Pain/psychology , Cognitive Behavioral Therapy/methods , Low Back Pain/therapy , Low Back Pain/psychology , Treatment OutcomeABSTRACT
Increasing emphasis on the use of real-world evidence (RWE) to support clinical policy and regulatory decision-making has led to a proliferation of guidance, advice, and frameworks from regulatory agencies, academia, professional societies, and industry. A broad spectrum of studies use real-world data (RWD) to produce RWE, ranging from randomized trials with outcomes assessed using RWD to fully observational studies. Yet, many proposals for generating RWE lack sufficient detail, and many analyses of RWD suffer from implausible assumptions, other methodological flaws, or inappropriate interpretations. The Causal Roadmap is an explicit, itemized, iterative process that guides investigators to prespecify study design and analysis plans; it addresses a wide range of guidance within a single framework. By supporting the transparent evaluation of causal assumptions and facilitating objective comparisons of design and analysis choices based on prespecified criteria, the Roadmap can help investigators to evaluate the quality of evidence that a given study is likely to produce, specify a study to generate high-quality RWE, and communicate effectively with regulatory agencies and other stakeholders. This paper aims to disseminate and extend the Causal Roadmap framework for use by clinical and translational researchers; three companion papers demonstrate applications of the Causal Roadmap for specific use cases.
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Although traditional phase II cancer trials are usually single arm, with tumor response as endpoint, and phase III trials are randomized and incorporate interim analyses with progression-free survival or other failure time as endpoint, this paper proposes a new approach that seamlessly expands a randomized phase II study of response rate into a randomized phase III study of time to failure. This approach is based on advances in group sequential designs and joint modeling of the response rate and time to event. The joint modeling is reflected in the primary and secondary objectives of the trial, and the sequential design allows the trial to adapt to increase in information on response and survival patterns during the course of the trial and to stop early either for conclusive evidence on efficacy of the experimental treatment or for the futility in continuing the trial to demonstrate it, on the basis of the data collected so far.
Subject(s)
Clinical Trials, Phase II as Topic/methods , Clinical Trials, Phase III as Topic/methods , Antineoplastic Agents/therapeutic use , Bone Neoplasms/secondary , Computer Simulation , Disease-Free Survival , Humans , Male , Models, Statistical , Neoplasms, Hormone-Dependent/drug therapy , Neoplasms, Hormone-Dependent/pathology , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/pathology , Research DesignABSTRACT
BACKGROUND: Advances in molecular therapeutics in the past decade have opened up new possibilities for treating cancer patients with personalized therapies, using biomarkers to determine which treatments are most likely to benefit them, but there are difficulties and unresolved issues in the development and validation of biomarker-based personalized therapies. We develop a new clinical trial design to address some of these issues. The goal is to capture the strengths of the frequentist and Bayesian approaches to address this problem in the recent literature and to circumvent their limitations. METHODS: We use generalized likelihood ratio tests of the intersection null and enriched strategy null hypotheses to derive a novel clinical trial design for the problem of advancing promising biomarker-guided strategies toward eventual validation. We also investigate the usefulness of adaptive randomization (AR) and futility stopping proposed in the recent literature. RESULTS: Simulation studies demonstrate the advantages of testing both the narrowly focused enriched strategy null hypothesis related to validating a proposed strategy and the intersection null hypothesis that can accommodate to a potentially successful strategy. AR and early termination of ineffective treatments offer increased probability of receiving the preferred treatment and better response rates for patients in the trial, at the expense of more complicated inference under small-to-moderate total sample sizes and some reduction in power. LIMITATIONS: The binary response used in the development phase may not be a reliable indicator of treatment benefit on long-term clinical outcomes. In the proposed design, the biomarker-guided strategy (BGS) is not compared to 'standard of care', such as physician's choice that may be informed by patient characteristics. Therefore, a positive result does not imply superiority of the BGS to 'standard of care'. The proposed design and tests are valid asymptotically. Simulations are used to examine small-to-moderate sample properties. CONCLUSION: Innovative clinical trial designs are needed to address the difficulties and issues in the development and validation of biomarker-based personalized therapies. The article shows the advantages of using likelihood inference and interim analysis to meet the challenges in the sample size needed and in the constantly evolving biomarker landscape and genomic and proteomic technologies.
Subject(s)
Biomarkers , Clinical Trials as Topic/methods , Precision Medicine , Research Design , Bayes Theorem , Drug Resistance , Early Termination of Clinical Trials , Female , Humans , Models, Statistical , Ovarian Neoplasms/drug therapy , Platinum/therapeutic use , Randomized Controlled Trials as Topic , Sample SizeABSTRACT
Background: The incidence and severity of coronavirus disease 19 (COVID-19) is substantially higher in men. Sex hormones may be a potential mechanism for differences in COVID-19 outcome in men and women. We hypothesized that men treated with androgen deprivation therapy (ADT) have lower incidence and severity of COVID-19. Methods: We conducted an observational study of male Veterans treated in the Veterans Health Administration from February 15th to July 15th, 2020. We developed a propensity score model to predict the likelihood to undergo Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) testing. We performed multivariable logistic regression modeling adjusted with inverse probability weighting to examine the relationship between ADT and COVID-19 incidence. We conducted logistic regression analysis among COVID-19 patients to test the association between ADT and COVID-19 severity. Results: We identified a large cohort of 246,087 VA male patients who had been tested for SARS-CoV-2, of whom 3,057 men were exposed to ADT, and 36,096 men with cancer without ADT. Of these, 295 ADT patients and 2,427 cancer patients not on ADT had severe COVID-19 illness. In the primary, propensity-weighted comparison of ADT patients to cancer patients not on ADT, ADT was associated with decreased likelihood of testing positive for SARS-CoV-2 (adjusted OR, 0.88 [95% CI, 0.81-0.95]; p = 0.001). Furthermore, ADT was associated with fewer severe COVID-19 outcomes (OR 0.72 [95% CI 0.53-0.96]; p = 0.03). Conclusion: ADT is associated with reduced incidence and severity of COVID-19 amongst male Veterans. Testosterone and androgen receptor signaling may confer increased risk for SARS-CoV-2 infection and contribute to severe COVID-19 pathophysiology in men.
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PURPOSE: Severe community-acquired pneumonia (CAP) requiring intensive care unit admission is associated with significant acute and long-term morbidity and mortality. We hypothesized that downregulation of systemic and pulmonary inflammation with prolonged low-dose methylprednisolone treatment would accelerate pneumonia resolution and improve clinical outcomes. METHODS: This double-blind, randomized, placebo-controlled clinical trial recruited adult patients within 72-96 h of hospital presentation. Patients were randomized in 1:1 ratio; an intravenous 40 mg loading bolus was followed by 40 mg/day through day 7 and progressive tapering during the 20-day treatment course. Randomization was stratified by site and need for mechanical ventilation (MV) at the time of randomization. Outcomes included a primary endpoint of 60-day all-cause mortality and secondary endpoints of morbidity and mortality up to 1 year of follow-up. RESULTS: Between January 2012 and April 2016, 586 patients from 42 Veterans Affairs Medical Centers were randomized, short of the 1420 target sample size because of low recruitment. 584 patients were included in the analysis. There was no significant difference in 60-day mortality between the methylprednisolone and placebo arms (16% vs. 18%; adjusted odds ratio 0.90, 95% CI 0.57-1.40). There were no significant differences in secondary outcomes or complications. CONCLUSIONS: In patients with severe CAP, prolonged low-dose methylprednisolone treatment did not significantly reduce 60-day mortality. Treatment was not associated with increased complications.
Subject(s)
Community-Acquired Infections , Pneumonia , Adult , Community-Acquired Infections/drug therapy , Critical Illness/therapy , Humans , Methylprednisolone/therapeutic use , Pneumonia/drug therapy , Respiration, Artificial , Treatment OutcomeABSTRACT
Importance: Posttraumatic stress disorder (PTSD) is a prevalent and serious mental health problem. Although there are effective psychotherapies for PTSD, there is little information about their comparative effectiveness. Objective: To compare the effectiveness of prolonged exposure (PE) vs cognitive processing therapy (CPT) for treating PTSD in veterans. Design, Setting, and Participants: This randomized clinical trial assessed the comparative effectiveness of PE vs CPT among veterans with military-related PTSD recruited from outpatient mental health clinics at 17 Department of Veterans Affairs medical centers across the US from October 31, 2014, to February 1, 2018, with follow-up through February 1, 2019. The primary outcome was assessed using centralized masking. Tested hypotheses were prespecified before trial initiation. Data were analyzed from October 5, 2020, to May 5, 2021. Interventions: Participants were randomized to 1 of 2 individual cognitive-behavioral therapies, PE or CPT, delivered according to a flexible protocol of 10 to 14 sessions. Main Outcomes and Measures: The primary outcome was change in PTSD symptom severity on the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) from before treatment to the mean after treatment across posttreatment and 3- and 6-month follow-ups. Secondary outcomes included other symptoms, functioning, and quality of life. Results: Analyses were based on all 916 randomized participants (730 [79.7%] men and 186 [20.3%] women; mean [range] age 45.2 [21-80] years), with 455 participants randomized to PE (mean CAPS-5 score at baseline, 39.9 [95% CI, 39.1-40.7] points) and 461 participants randomized to CPT (mean CAPS-5 score at baseline, 40.3 [95% CI, 39.5-41.1] points). PTSD severity on the CAPS-5 improved substantially in both PE (standardized mean difference [SMD], 0.99 [95% CI, 0.89-1.08]) and CPT (SMD, 0.71 [95% CI, 0.61-0.80]) groups from before to after treatment. Mean improvement was greater in PE than CPT (least square mean, 2.42 [95% CI, 0.53-4.31]; P = .01), but the difference was not clinically significant (SMD, 0.17). Results for self-reported PTSD symptoms were comparable with CAPS-5 findings. The PE group had higher odds of response (odds ratio [OR], 1.32 [95% CI, 1.00-1.65]; P < .001), loss of diagnosis (OR, 1.43 [95% CI, 1.12-1.74]; P < .001), and remission (OR, 1.62 [95% CI, 1.24-2.00]; P < .001) compared with the CPT group. Groups did not differ on other outcomes. Treatment dropout was higher in PE (254 participants [55.8%]) than in CPT (215 participants [46.6%]; P < .01). Three participants in the PE group and 1 participant in the CPT group were withdrawn from treatment, and 3 participants in each treatment dropped out owing to serious adverse events. Conclusions and Relevance: This randomized clinical trial found that although PE was statistically more effective than CPT, the difference was not clinically significant, and improvements in PTSD were meaningful in both treatment groups. These findings highlight the importance of shared decision-making to help patients understand the evidence and select their preferred treatment. Trial Registration: ClinicalTrials.gov Identifier: NCT01928732.
Subject(s)
Cognitive Behavioral Therapy , Implosive Therapy , Stress Disorders, Post-Traumatic/therapy , Adult , Female , Humans , Male , Middle Aged , Treatment Outcome , United States , VeteransABSTRACT
Saphenous vein grafts (SVGs) have high rates of in-stent restenosis (ISR). We compared the baseline clinical and angiographic characteristics of patients and lesions that did develop ISR with those who did not develop ISR during a median follow-up of 2.7 years in the DIVA study (NCT01121224). We also examined the ISR types using the Mehran classification. ISR developed in 119 out of the 575 DIVA patients (21%), with similar incidence among patients with drug-eluting stents and bare-metal stents (BMS) (21% vs 21%, p = 0.957). Patients in the ISR group were younger (67 ± 7 vs 69 ± 8 years, p = 0.04) and less likely to have heart failure (27% vs 38%, p = 0.03) and SVG lesions with Thrombolysis In Myocardial Infarction 3 flow before the intervention (77% vs 83%, p <0.01), but had a higher number of target SVG lesions (1.33 ± 0.64 vs 1.16 ± 0.42, p <0.01), more stents implanted in the target SVG lesions (1.52 ± 0.80 vs 1.31 ± 0.66, p <0.01), and longer total stent length (31.37 ± 22.11 vs 25.64 ± 17.42 mm, p = 0.01). The incidence of diffuse ISR was similar in patients who received drug-eluting-stents and BMS (57% vs 54%, p = 0.94), but BMS patients were more likely to develop occlusive restenosis (17% vs 33%, p = 0.05).
Subject(s)
Coronary Artery Bypass/adverse effects , Coronary Artery Disease/surgery , Coronary Restenosis/epidemiology , Drug-Eluting Stents/adverse effects , Graft Occlusion, Vascular/epidemiology , Saphenous Vein/transplantation , Age Factors , Aged , Coronary Angiography , Coronary Artery Disease/complications , Coronary Artery Disease/mortality , Coronary Restenosis/diagnosis , Female , Graft Occlusion, Vascular/diagnosis , Humans , Male , Middle Aged , Prosthesis Design , Risk FactorsABSTRACT
PURPOSE: A significant barrier to efficient antibiotic management of infection is that the standard diagnostic methodologies do not provide results at the point of care. The delays between sample collection and bacterial culture and antibiotic susceptibility reporting have led to empirical use of antibiotics, contributing to the emergence of drug resistant pathogens. As a key step toward the development of a point of care device for determining the antibiotic susceptibility of urinary tract pathogens, we report on a biosensor based antimicrobial susceptibility test. MATERIALS AND METHODS: For assay development bacteria were cultured with or without antibiotics, and growth was quantitated by determining viable counts and electrochemical biosensor measurement of bacterial 16S rRNA. To determine antibiotic susceptibility directly from patient samples, urine was cultured on antibiotic plates for 2.5 hours and growth was determined by electrochemical measurement of bacterial 16S rRNA. For assay validation 252 urine samples were collected from patients at the Spinal Cord Injury Service at Veterans Affairs Palo Alto Health Care System. The biosensor based antimicrobial susceptibility test was completed for samples containing gram-negative organisms. Pathogen identification and antibiotic susceptibility results were compared between our assay and standard microbiological analysis. RESULTS: A direct biosensor quantitation of bacterial 16S rRNA can be used to monitor bacterial growth for a biosensor based antimicrobial susceptibility test. Clinical validation of a biosensor based antimicrobial susceptibility test with patient urine samples demonstrated that this test was 94% accurate in 368 pathogen-antibiotic tests compared to standard microbiological analysis. CONCLUSIONS: This biosensor based antimicrobial susceptibility test, in concert with our previously described pathogen identification assay, can provide culture and susceptibility information directly from a urine sample within 3.5 hours.