Training New DMC Members: A Call to Action

Historically, clinical trialists developed DMC expertise and experience with "on the job training". Clinical trialists have recognized a large and growing gap between the demand and supply of trained DMC members due in part to the huge increase in ongoing clinical trials. A critical need exists to increase the supply of DMC trained clinicians and biostatisticians. Despite a rich collection of published training material, many have recommended a mentoring process to train clinical trialists and data scientists lacking DMC experience. We propose that academic, regulatory, industry and other leaders in clinical trials support including investigators lacking DMC experience as members of a DMC so that they can be trained to learn about the DMC processes during conduct of an actual trial".

The Data Monitoring Committee: A Collective or a Collection?

In this commentary, we urge that a Data Monitoring Committee (DMC) should operate as a collective, that is, as a unitary whole. In so doing, its recommendations should emerge through a consensus development process, not through a vote of the members. The summary notes of its closed session, that is, its minutes, should report the recommendations of the DMC and, if necessary, the justification for those recommendations; it should not attribute opinions to individual members. Importantly, the proceedings of the DMC meetings should not be electronically recorded.

Experiences of the Data Monitoring Committee for the RECOVERY trial, a large-scale adaptive platform randomised trial of treatments for patients hospitalised with COVID-19

AIM

To inform the oversight of future clinical trials during a pandemic, we summarise the experiences of the Data Monitoring Committee (DMC) for the Randomised Evaluation of COVID therapy trial (RECOVERY), a large-scale randomised adaptive platform clinical trial of treatments for hospitalised patients with COVID-19.

METHODS AND FINDINGS

During the first 24 months of the trial (March 2020 to February 2022), the DMC oversaw accumulating data for 14 treatments in adults (plus 10 in children) involving > 45,000 randomised patients. Five trial aspects key for the DMC in performing its role were: a large committee of members, including some with extensive DMC experience and others who had broad clinical expertise; clear strategic planning, communication, and responsiveness by the trial principal investigators; data collection and analysis systems able to cope with phases of very rapid recruitment and link to electronic health records; an ability to work constructively with regulators (and other DMCs) to address emerging concerns without the need to release unblinded mortality results; and the use of videoconferencing systems that enabled national and international members to meet at short notice and from home during the pandemic when physical meetings were impossible. Challenges included that the first four treatments introduced were effectively 'competing' for patients (increasing pressure to make rapid decisions on each one); balancing the global health imperative to report on findings with the need to maintain confidentiality until the results were sufficiently certain to appropriately inform treatment decisions; and reliably assessing safety, especially for newer agents introduced after the initial wave and in the small numbers of pregnant women and children included. We present a series of case vignettes to illustrate some of the issues and the DMC decision-making related to hydroxychloroquine, dexamethasone, casirivimab + imdevimab, and tocilizumab.

CONCLUSIONS

RECOVERY's streamlined adaptive platform design, linked to hospital-level and population-level health data, enabled the rapid and reliable assessment of multiple treatments for hospitalised patients with COVID-19. The later introduction of factorial assessments increased the trial's efficiency, without compromising the DMC's ability to assess safety and efficacy. Requests for the release of unblinded primary outcome data to regulators at points when data were not mature required significant efforts in communication with the regulators by the DMC to avoid inappropriate early trial termination.

Dapagliflozin in Heart Failure with Mildly Reduced or Preserved Ejection Fraction

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT2) inhibitors reduce the risk of hospitalization for heart failure and cardiovascular death among patients with chronic heart failure and a left ventricular ejection fraction of 40% or less. Whether SGLT2 inhibitors are effective in patients with a higher left ventricular ejection fraction remains less certain.

METHODS

We randomly assigned 6263 patients with heart failure and a left ventricular ejection fraction of more than 40% to receive dapagliflozin (at a dose of 10 mg once daily) or matching placebo, in addition to usual therapy. The primary outcome was a composite of worsening heart failure (which was defined as either an unplanned hospitalization for heart failure or an urgent visit for heart failure) or cardiovascular death, as assessed in a time-to-event analysis.

RESULTS

Over a median of 2.3 years, the primary outcome occurred in 512 of 3131 patients (16.4%) in the dapagliflozin group and in 610 of 3132 patients (19.5%) in the placebo group (hazard ratio, 0.82; 95% confidence interval [CI], 0.73 to 0.92; P<0.001). Worsening heart failure occurred in 368 patients (11.8%) in the dapagliflozin group and in 455 patients (14.5%) in the placebo group (hazard ratio, 0.79; 95% CI, 0.69 to 0.91); cardiovascular death occurred in 231 patients (7.4%) and 261 patients (8.3%), respectively (hazard ratio, 0.88; 95% CI, 0.74 to 1.05). Total events and symptom burden were lower in the dapagliflozin group than in the placebo group. Results were similar among patients with a left ventricular ejection fraction of 60% or more and those with a left ventricular ejection fraction of less than 60%, and results were similar in prespecified subgroups, including patients with or without diabetes. The incidence of adverse events was similar in the two groups.

CONCLUSIONS

Dapagliflozin reduced the combined risk of worsening heart failure or cardiovascular death among patients with heart failure and a mildly reduced or preserved ejection fraction. (Funded by AstraZeneca; DELIVER ClinicalTrials.gov number, NCT03619213.).

Dapagliflozin across the range of ejection fraction in patients with heart failure: a patient-level, pooled meta-analysis of DAPA-HF and DELIVER

Whether the sodium-glucose cotransporter 2 inhibitor dapagliflozin reduces the risk of a range of morbidity and mortality outcomes in patients with heart failure regardless of ejection fraction is unknown. A patient-level pooled meta-analysis of two trials testing dapagliflozin in participants with heart failure and different ranges of left ventricular ejection fraction (≤40% and >40%) was pre-specified to examine the effect of treatment on endpoints that neither trial, individually, was powered for and to test the consistency of the effect of dapagliflozin across the range of ejection fractions. The pre-specified endpoints were: death from cardiovascular causes; death from any cause; total hospital admissions for heart failure; and the composite of death from cardiovascular causes, myocardial infarction or stroke (major adverse cardiovascular events (MACEs)). A total of 11,007 participants with a mean ejection fraction of 44% (s.d. 14%) were included. Dapagliflozin reduced the risk of death from cardiovascular causes (hazard ratio (HR) 0.86, 95% confidence interval (CI) 0.76-0.97; P = 0.01), death from any cause (HR 0.90, 95% CI 0.82-0.99; P = 0.03), total hospital admissions for heart failure (rate ratio 0.71, 95% CI 0.65-0.78; P < 0.001) and MACEs (HR 0.90, 95% CI 0.81-1.00; P = 0.045). There was no evidence that the effect of dapagliflozin differed by ejection fraction. In a patient-level pooled meta-analysis covering the full range of ejection fractions in patients with heart failure, dapagliflozin reduced the risk of death from cardiovascular causes and hospital admissions for heart failure (PROSPERO: CRD42022346524).

Efficacy and Safety of Dapagliflozin in Heart Failure with Mildly Reduced or Preserved Ejection Fraction According to Age: The DELIVER Trial

Background: The prevalence of heart failure (HF) with mildly reduced or preserved ejection fraction (EF) markedly increases with age, with older individuals disproportionately facing excess risk for mortality and hospitalization. Methods: The DELIVER trial (Dapagliflozin Evaluation to Improve the LIVEs of Patients With PReserved Ejection Fraction Heart Failure) randomized patients with New York Heart Association functional class II-IV and left ventricular EF >40% to either dapagliflozin or placebo for a median follow-up period of 2.3 years. We examined efficacy and safety outcomes by age categories (<55, 55-64, 65-74 and ≥75 years) and across age as a continuous measure. Results: Among 6,263 randomized patients (aged 40-99 years, mean age 71.7 ± 9.6 years), 338 (5.4%) were <55 years, 1,007 (16.1%) were 55-64 years, 2,326 (37.1%) were 65-74 years, and 2,592 (41.4%) were ≥75 years. Dapagliflozin reduced the risk of the primary composite outcome compared with placebo in all age categories (p_interaction=0.95) and across the age spectrum as a continuous function (p_interaction=0.76). Similar benefits were observed for the components of the primary outcome, with no significant interaction between randomized treatment and age category. Adverse events occurred more frequently with increasing age, but there were no significant differences in predefined safety outcomes between patients randomized to dapagliflozin and placebo across all age categories. Conclusions: In patients with HF and mildly reduced or preserved EF enrolled in DELIVER, Dapagliflozin reduced cardiovascular death or HF events across the spectrum of age, with a consistent safety profile, including among the traditionally under-treated older segment of patients ≥75 years. Clinical Trial Registration: URL: https://www.clinicaltrials.gov Unique identifier: NCT03619213.

Dapagliflozin in Patients Recently Hospitalized With Heart Failure and Mildly Reduced or Preserved Ejection Fraction

BACKGROUND

Patients recently hospitalized for heart failure (HF) are at high risk for rehospitalization and death.

OBJECTIVES

The purpose of this study was to investigate clinical outcomes and response to dapagliflozin in patients with HF with mildly reduced or preserved left ventricular ejection fraction (LVEF) who were enrolled during or following hospitalization.

METHODS

The DELIVER (Dapagliflozin Evaluation to Improve the LIVES of Patients With PReserved Ejection Fraction Heart Failure) trial randomized patients with HF and LVEF >40% to dapagliflozin or placebo. DELIVER permitted randomization during or shortly after hospitalization for HF in clinically stable patients off intravenous HF therapies. This prespecified analysis investigated whether recent HF hospitalization modified risk of clinical events or response to dapagliflozin. The primary outcome was worsening HF event or cardiovascular death.

RESULTS

Of 6,263 patients in DELIVER, 654 (10.4%) were randomized during HF hospitalization or within 30 days of discharge. Recent HF hospitalization was associated with greater risk of the primary outcome after multivariable adjustment (HR: 1.88; 95% CI: 1.60-2.21; P < 0.001). Dapagliflozin reduced the primary outcome by 22% in recently hospitalized patients (HR: 0.78; 95% CI: 0.60-1.03) and 18% in patients without recent hospitalization (HR: 0.82; 95% CI: 0.72-0.94; P_interaction = 0.71). Rates of adverse events, including volume depletion, diabetic ketoacidosis, or renal events, were similar with dapagliflozin and placebo in recently hospitalized patients.

CONCLUSIONS

Dapagliflozin safely reduced risk of worsening HF or cardiovascular death similarly in patients with and without history of recent HF hospitalization. Starting dapagliflozin during or shortly after HF hospitalization in patients with mildly reduced or preserved LVEF appears safe and effective. (Dapagliflozin Evaluation to Improve the LIVEs of Patients With PReserved Ejection Fraction Heart Failure [DELIVER]; NCT03619213).

Baseline Characteristics of Patients With HF With Mildly Reduced and Preserved Ejection Fraction: DELIVER Trial

OBJECTIVES

This report describes the baseline clinical profiles and management of DELIVER (Dapagliflozin Evaluation to Improve the Lives of Patients With Preserved Ejection Fraction Heart Failure) trial participants and how these compare with those in other contemporary heart failure with preserved ejection fraction trials.

BACKGROUND

The DELIVER trial was designed to evaluate the effects of the sodium-glucose cotransporter-2 inhibitor dapagliflozin on cardiovascular death, heart failure (HF) hospitalization, or urgent HF visits in patients with HF with mildly reduced and preserved left ventricular ejection fraction (LVEF).

METHODS

Adults with symptomatic HF and LVEF >40%, with or without type 2 diabetes mellitus, elevated N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, and evidence of structural heart disease were randomized to dapagliflozin 10 mg once daily or matching placebo.

RESULTS

A total of 6,263 patients were randomized (mean age: 72 ± 10 years; 44% women; 45% type 2 diabetes mellitus; 45% with body mass index ≥30 kg/m²; and 57% with history of atrial fibrillation or flutter). Most participants had New York Heart Association functional class II symptoms (75%). Baseline mean LVEF was 54.2 ± 8.8% and median NT-proBNP of 1,399 pg/mL (IQR: 962 to 2,210 pg/mL) for patients in atrial fibrillation/flutter compared with 716 pg/mL (IQR: 469 to 1,281 pg/mL) in those who were not. Patients in both hospitalized and ambulatory settings were enrolled, including 10% enrolled in-hospital or within 30 days of a hospitalization for HF. Eighteen percent of participants had HF with improved LVEF.

CONCLUSIONS

DELIVER is the largest and broadest clinical trial of this population to date and enrolled high-risk, well-treated patients with HF with mildly reduced and preserved LVEF. (Dapagliflozin Evaluation to Improve the Lives of Patients With Preserved Ejection Fraction Heart Failure [NCT03619213]).

Dapagliflozin in heart failure with preserved and mildly reduced ejection fraction: rationale and design of the DELIVER trial

Aims

Sodium–glucose co‐transporter 2 (SGLT2) inhibitors, originally developed as glucose‐lowering agents, have been shown to reduce heart failure hospitalizations in patients with type 2 diabetes without established heart failure, and in patients with heart failure with and without diabetes. Their role in patients with heart failure with preserved and mildly reduced ejection fraction remains unknown.

Methods

Dapagliflozin Evaluation to Improve the LIVEs of Patients With PReserved Ejection Fraction Heart Failure (DELIVER) is an international, multicentre, parallel group, event‐driven, randomized, double‐blind trial in patients with chronic heart failure and left ventricular ejection fraction (LVEF) >40%, comparing the effect of dapagliflozin 10 mg once daily, vs. placebo, in addition to standard of care. Patients with or without diabetes, with signs and symptoms of heart failure, a LVEF >40%, elevation in natriuretic peptides and evidence of structural heart disease are eligible. The primary endpoint is time‐to‐first cardiovascular death or worsening heart failure event (heart failure hospitalization or urgent heart failure visit), and will be assessed in dual primary analyses – the full population and in those with LVEF <60%. The study is event‐driven and will target 1117 primary events. A total of 6263 patients have been randomized.

Conclusions

DELIVER will determine the efficacy and safety of the SGLT2 inhibitor dapagliflozin, added to conventional therapy, in patients with heart failure and preserved and mildly reduced ejection fraction.

The Addition of a Defibrillator to Resynchronization Therapy Decreases Mortality in Patients With Nonischemic Cardiomyopathy

OBJECTIVES

The aim of this study was to determine whether patients with heart failure with reduced ejection fraction (HFrEF) due to nonischemic etiology eligible for cardiac resynchronization therapy (CRT) benefit from an implantable cardioverter-defibrillator (ICD).

BACKGROUND

It is uncertain whether CRT with an ICD (CRT-D) compared to without an ICD (CRT-P) is associated with a survival benefit in patients with nonischemic etiologies of HFrEF.

METHODS

Analyses of the COMPANION (Comparison of Medical Therapy, Pacing, and Defibrillation in Heart Failure) trial were performed, using Cox proportional hazards modeling stratified by HFrEF etiology of nonischemic cardiomyopathy (NICM) or ischemic cardiomyopathy (ICM). The primary outcome was all-cause mortality (ACM), and secondary outcomes were the combination of cardiovascular mortality or heart failure hospitalization and sudden cardiac death.

RESULTS

Among patients randomized to CRT (n = 1,212), 236 (19.5%) died, 131 and 105 in the CRT-P and CRT-D arms, respectively. The unadjusted and adjusted hazard ratios (HRs) for CRT-D versus CRT-P were both 0.84 (95% confidence interval [CI]: 0.65 to 1.09) for ACM, with a significant device-etiology interaction (p_interaction = 0.015 adjusted; p_interaction = 0.040 unadjusted). In patients with NICM (n = 555), CRT-D versus CRT-P was associated with reduced ACM (adjusted HR: 0.54; 95% CI: 0.34 to 0.86), while patients with ICM (n = 657) did not exhibit a between-device reduction in ACM (adjusted HR: 1.05; 95% CI: 0.77 to 1.44). The effects of CRT-D versus CRT-P on sudden cardiac death (advantage CRT-D) and cardiovascular mortality or heart failure hospitalization (no difference between CRT-P and CRT-D) were similar between the 2 HFrEF etiologies.

CONCLUSIONS

COMPANION patients with NICM exhibited a decrease in ACM associated with CRT-D but not CRT-P treatment, whereas patients with ICM did not.

Effect of High-Dose Trivalent vs Standard-Dose Quadrivalent Influenza Vaccine on Mortality or Cardiopulmonary Hospitalization in Patients With High-risk Cardiovascular Disease: A Randomized Clinical Trial

IMPORTANCE

Influenza is temporally associated with cardiopulmonary morbidity and mortality among those with cardiovascular disease who may mount a less vigorous immune response to vaccination. Higher influenza vaccine dose has been associated with reduced risk of influenza illness.

OBJECTIVE

To evaluate whether high-dose trivalent influenza vaccine compared with standard-dose quadrivalent influenza vaccine would reduce all-cause death or cardiopulmonary hospitalization in high-risk patients with cardiovascular disease.

DESIGN, SETTING, AND PARTICIPANTS

Pragmatic multicenter, double-blind, active comparator randomized clinical trial conducted in 5260 participants vaccinated for up to 3 influenza seasons in 157 sites in the US and Canada between September 21, 2016, and January 31, 2019. Patients with a recent acute myocardial infarction or heart failure hospitalization and at least 1 additional risk factor were eligible.

INTERVENTIONS

Participants were randomly assigned to receive high-dose trivalent (n = 2630) or standard-dose quadrivalent (n = 2630) inactivated influenza vaccine and could be revaccinated for up to 3 seasons.

MAIN OUTCOMES AND MEASURES

The primary outcome was the time to the composite of all-cause death or cardiopulmonary hospitalization during each enrolling season. The final date of follow-up was July 31, 2019. Vaccine-related adverse events were also assessed.

RESULTS

Among 5260 randomized participants (mean [SD] age, 65.5 [12.6] years; 3787 [72%] men; 3289 [63%] with heart failure) over 3 influenza seasons, there were 7154 total vaccinations administered and 5226 (99.4%) participants completed the trial. In the high-dose trivalent vaccine group, there were 975 primary outcome events (883 hospitalizations for cardiovascular or pulmonary causes and 92 deaths from any cause) among 884 participants during 3577 participant-seasons (event rate, 45 per 100 patient-years), whereas in the standard-dose quadrivalent vaccine group, there were 924 primary outcome events (846 hospitalizations for cardiovascular or pulmonary causes and 78 deaths from any cause) among 837 participants during 3577 participant-seasons (event rate, 42 per 100 patient-years) (hazard ratio, 1.06 [95% CI, 0.97-1.17]; P = .21). In the high-dose vs standard-dose groups, vaccine-related adverse reactions occurred in 1449 (40.5%) vs 1229 (34.4%) participants and severe adverse reactions occurred in 55 (2.1%) vs 44 (1.7%) participants.

CONCLUSIONS AND RELEVANCE

In patients with high-risk cardiovascular disease, high-dose trivalent inactivated influenza vaccine, compared with standard-dose quadrivalent inactivated influenza vaccine, did not significantly reduce all-cause mortality or cardiopulmonary hospitalizations. Influenza vaccination remains strongly recommended in this population.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02787044.

The independent statistician model: How well is it working?

With the initiation in the late 1960s of the data and safety monitoring board or equivalently the data monitoring committee in randomized clinical trials came the need for interim statistical reports for these committees to review for study conduct and early evidence of harm or overwhelming evidence of benefit, perhaps leading to early trial termination. Initially, the statistical team was part of the data coordinating center for the trial. Later, starting in the early 1990s in many industry-sponsored trials, this statistical unit was separated organizationally from the team that collected and managed the data. This unit, often referred to as the statistical data analysis center, prepares reports for the data monitoring committee, which cover study conduct, data quality and completeness, primary and secondary outcomes, and safety measures by study arm in an unblinded fashion. The role of the statistical data analysis center is critical to any well-functioning data monitoring committee. With the proliferation of data monitoring committees has grown the need for many more well-trained and experienced statistical data analysis centers. In my experience, some such units perform their tasks extremely well but many do not. There is a tremendous need and opportunity to provide training for statistical data analysis centers, and what sponsors and data monitoring committees should expect from statistical data analysis centers.

Long-Term Effect of Endothelin Receptor Antagonism With Bosentan on the Morbidity and Mortality of Patients With Severe Chronic Heart Failure: Primary Results of the ENABLE Trials

OBJECTIVES

The objective of this clinical trial was to evaluate the long-term effect of endothelin receptor antagonism with bosentan on the morbidity and mortality of patients with severe chronic heart failure.

BACKGROUND

Endothelin may play a role in heart failure, but short-term clinical trials with endothelin receptor antagonists have reported disappointing results. Long-term trials are lacking.

METHODS

In 2 identical double-blind trials, we randomly assigned 1,613 patients with New York Heart Association functional class IIIb to IV heart failure and an ejection fraction <35% to receive placebo or bosentan (target dose 125 mg twice daily) for a median of 1.5 years. The primary outcome for each trial was clinical status at 9 months (assessed by the hierarchical clinical composite); the primary outcome across the 2 trials was death from any cause or hospitalization for heart failure.

RESULTS

Bosentan did not influence clinical status at 9 months in either trial (p = 0.928 and p = 0.263). In addition, 321 patients in the placebo group and 312 patients in the bosentan group died or were hospitalized for heart failure (hazard ratio [HR]: 1.01; 95% confidence interval [CI]: 0.86 to 1.18; p = 0.90). The bosentan group experienced fluid retention within the first 2 to 4 weeks, as evidenced by increased peripheral edema, weight gain, decreases in hemoglobin, and an increased risk of hospitalization for heart failure, despite intensification of background diuretics. During follow-up, 173 patients died in the placebo group and 160 patients died in the bosentan group (HR: 0.94; 95% CI: 0.75 to 1.16). About 10% of the bosentan group showed meaningful increases in hepatic transaminases, but none had acute or chronic liver failure.

CONCLUSIONS

Bosentan did not improve the clinical course or natural history of patients with severe chronic heart failure and but caused early and important fluid retention.

Recommendations for data monitoring committees from the Clinical Trials Transformation Initiative

Background/aims Use of data monitoring committees to oversee clinical trials was first proposed nearly 50 years ago. Since then, data monitoring committee use in clinical trials has increased and evolved. Nonetheless, there are no well-defined criteria for determining the need for a data monitoring committee, and considerable variability exists in data monitoring committee composition and conduct. To understand and describe the role and function of data monitoring committees, and establish best practices for data monitoring committee trial oversight, the Clinical Trials Transformation Initiative-a public-private partnership to improve clinical trials-launched a multi-stakeholder project. Methods The data monitoring committee project team included 16 individuals charged with (1) clarifying the purpose of data monitoring committees, (2) identifying best practices for independent data monitoring committee conduct, (3) describing effective communication practices, and (4) developing strategies for training data monitoring committee members. Evidence gathering included a survey, a series of focus group discussions, and a 2-day expert meeting aimed at achieving consensus opinions that form the foundation of our data monitoring committee recommendations. Results We define the role of the data monitoring committee as an advisor to the research sponsor on whether to continue, modify, or terminate a trial based on periodic assessment of trial data. Data monitoring committees should remain independent from the sponsor and be composed of members with no relevant conflicts of interest. Representation on a data monitoring committee generally should include at least one clinician with expertise in the therapeutic area being studied, a biostatistician, and a designated chairperson who has experience with clinical trials and data monitoring. Data monitoring committee meetings are held periodically to evaluate the unmasked data from ongoing trials, but the content and conduct of meetings may vary depending on specific goals or topics for deliberation. To guide data monitoring committee conduct and communication plans, a charter consistent with the protocol's research design and statistical analysis plan should be developed and agreed upon by the sponsor and the data monitoring committee prior to patient enrollment. We recommend concise and flexible charters that explain roles, responsibilities, operational issues, and how data monitoring committee recommendations are generated and communicated. The demand for data monitoring committee members appears to exceed the current pool of qualified individuals. To prepare a new generation of trained data monitoring committee members, we encourage a combination of didactic educational programs, practical experience, and skill development through apprenticeships and mentoring by experienced data monitoring committee members. Conclusion Our recommendations address data monitoring committee use, conduct, communication practices, and member preparation and training. Furthermore recommendations form the foundation for ongoing efforts to improve clinical trial oversight and enhance the safety and integrity of clinical research. These recommendations serve as a call to action for implementation of best practices that benefit study participants, study sponsors, and society.

Interpretation of the evidence for the efficacy and safety of statin therapy

This Review is intended to help clinicians, patients, and the public make informed decisions about statin therapy for the prevention of heart attacks and strokes. It explains how the evidence that is available from randomised controlled trials yields reliable information about both the efficacy and safety of statin therapy. In addition, it discusses how claims that statins commonly cause adverse effects reflect a failure to recognise the limitations of other sources of evidence about the effects of treatment. Large-scale evidence from randomised trials shows that statin therapy reduces the risk of major vascular events (ie, coronary deaths or myocardial infarctions, strokes, and coronary revascularisation procedures) by about one-quarter for each mmol/L reduction in LDL cholesterol during each year (after the first) that it continues to be taken. The absolute benefits of statin therapy depend on an individual's absolute risk of occlusive vascular events and the absolute reduction in LDL cholesterol that is achieved. For example, lowering LDL cholesterol by 2 mmol/L (77 mg/dL) with an effective low-cost statin regimen (eg, atorvastatin 40 mg daily, costing about £2 per month) for 5 years in 10 000 patients would typically prevent major vascular events from occurring in about 1000 patients (ie, 10% absolute benefit) with pre-existing occlusive vascular disease (secondary prevention) and in 500 patients (ie, 5% absolute benefit) who are at increased risk but have not yet had a vascular event (primary prevention). Statin therapy has been shown to reduce vascular disease risk during each year it continues to be taken, so larger absolute benefits would accrue with more prolonged therapy, and these benefits persist long term. The only serious adverse events that have been shown to be caused by long-term statin therapy-ie, adverse effects of the statin-are myopathy (defined as muscle pain or weakness combined with large increases in blood concentrations of creatine kinase), new-onset diabetes mellitus, and, probably, haemorrhagic stroke. Typically, treatment of 10 000 patients for 5 years with an effective regimen (eg, atorvastatin 40 mg daily) would cause about 5 cases of myopathy (one of which might progress, if the statin therapy is not stopped, to the more severe condition of rhabdomyolysis), 50-100 new cases of diabetes, and 5-10 haemorrhagic strokes. However, any adverse impact of these side-effects on major vascular events has already been taken into account in the estimates of the absolute benefits. Statin therapy may cause symptomatic adverse events (eg, muscle pain or weakness) in up to about 50-100 patients (ie, 0·5-1·0% absolute harm) per 10 000 treated for 5 years. However, placebo-controlled randomised trials have shown definitively that almost all of the symptomatic adverse events that are attributed to statin therapy in routine practice are not actually caused by it (ie, they represent misattribution). The large-scale evidence available from randomised trials also indicates that it is unlikely that large absolute excesses in other serious adverse events still await discovery. Consequently, any further findings that emerge about the effects of statin therapy would not be expected to alter materially the balance of benefits and harms. It is, therefore, of concern that exaggerated claims about side-effect rates with statin therapy may be responsible for its under-use among individuals at increased risk of cardiovascular events. For, whereas the rare cases of myopathy and any muscle-related symptoms that are attributed to statin therapy generally resolve rapidly when treatment is stopped, the heart attacks or strokes that may occur if statin therapy is stopped unnecessarily can be devastating.

Type 2 diabetes mellitus development programs in the new regulatory environment with cardiovascular safety requirements

For type 2 diabetes mellitus treatment and clinical development, proper evaluation of cardiovascular risk has been required by regulatory agencies (eg, the US Food and Drug Administration) since cardiovascular safety is very important in this patient population. The US Food and Drug Administration issued general guidelines for cardiovascular safety evaluation that outlined the requirements considered adequate for cardiovascular safety evaluation. However, there are multiple options to obtain the data and fulfill these requirements. In this paper, we outline the potential pathways and challenges in various aspects of cardiovascular safety evaluation in type 2 diabetes clinical development, including study design, populations, and endpoints. Specifically, we discuss some challenges in statistical analysis which have implications for the design, implementation, and interpretation of these outcome studies.

Aspirin increases nitric oxide formation in chronic stable coronary disease

INTRODUCTION

There are no published randomized data on secondary prevention in humans about whether aspirin affects nitric oxide (NO) formation. In patients with chronic stable coronary disease, we tested whether aspirin at clinically relevant doses increases NO formation.

MATERIALS AND METHODS

In a randomized, double-blind trial, 37 patients from 2 cardiology office practices were assigned to daily doses of 81, 162.5, 325, 650, or 1300 aspirin for 12 weeks. Primary prespecified outcome measures were changes in heme oxygenase (HO-1), a downstream target of NO formation, and asymmetrical dimethyl arginine (ADMA), a competitive inhibitor of NO synthase.

RESULTS

There were no significant differences for HO-1 or ADMA between any of the clinically relevant doses of aspirin tested, so all were combined. For HO-1, there was a significant increase (10.29 ± 2.44, P < .001) from baseline (15.37 ± 1.85) to week 12 (25.66 ± 1.57). The mean ratio (MR) of week 12 to baseline for HO-1 was significantly higher than 1.0 (1.67, confidence interval [CI] from 1.60 to 1.74, P < .001). For ADMA, there was a significant decrease (-0.24 ± 0.11, P < .001) from baseline (0.78 ± 0.08) to week 12 (0.54 ± 0.07). The MR of week 12 to baseline for ADMA was significantly lower than 1.0 (0.69, CI from 0.66 to 0.73, P < .001).

CONCLUSIONS

In patients with chronic stable coronary disease, all clinically relevant daily doses of aspirin tested, from 81 to 1300 mg, produce similar and statistically significant increases in HO-1 and decreases in ADMA. These are the first randomized data on secondary prevention patients. These data support the hypothesis that aspirin has additional beneficial effects mediated through NO formation. Further research, including direct randomized comparisons on atherosclerosis using noninvasive techniques as well as on occlusive vascular disease events, is necessary.

Effects of low-dose oral enoximone administration on mortality, morbidity, and exercise capacity in patients with advanced heart failure: the randomized, double-blind, placebo-controlled, parallel group ESSENTIAL trials

Aims

Use of inotropic agents in patients with heart failure (HF) has been limited by adverse effects on outcomes. However, administration of positive inotropes at lower doses and concomitant treatment with beta-blockers might increase benefit–risk ratio. We investigated the effects of low doses of the positive inotrope enoximone on symptoms, exercise capacity, and major clinical outcomes in patients with advanced HF who were also treated with beta-blockers and other guideline-recommended background therapy.

Methods and results

The Studies of Oral Enoximone Therapy in Advanced HF (ESSENTIAL) programme consisted of two identical, randomized, double-blind, placebo-controlled trials that differed only by geographic location (North and South America: ESSENTIAL-I; Europe: ESSENTIAL-II). Patients with New York Heart Association class III–IV HF symptoms, left ventricular ejection fraction ≤30%, and one hospitalization or two ambulatory visits for worsening HF in the previous year were eligible for participation in the trials. The trials had three co-primary endpoints: (i) the composite of time to all-cause mortality or cardiovascular hospitalization, analysed in the two ESSENTIAL trials combined; (ii) the 6 month change from baseline in the 6 min walk test distance (6MWTD); and (iii) the Patient Global Assessment (PGA) at 6 months, both analysed in each trial separately. ESSENTIAL-I and -II randomized 1854 subjects at 211 sites in 16 countries. In the combined trials, all-cause mortality and the composite, first co-primary endpoint did not differ between the two treatment groups [hazard ratio (HR) 0.97; 95% confidence interval (CI) 0.80–1.17; and HR 0.98; 95% CI 0.86–1.12, respectively, for enoximone vs. placebo]. The two other co-primary endpoints were analysed separately in the two ESSENTIAL trials, as prospectively designed in the protocol. The 6MWTD increased with enoximone, compared with placebo, in ESSENTIAL-I (P = 0.025, not reaching, however, the pre-specified criterion for statistical significance of P < 0.020), but not in ESSENTIAL-II. No difference in PGA was observed in either trial.

Conclusion

Although low-dose enoximone appears to be safe in patients with advanced HF, major clinical outcomes are not improved.

Factors Associated With Outcome in Heart Failure With Preserved Ejection Fraction

Background—

The determinants of prognosis in patients with heart failure and preserved ejection fraction (HF-PEF) are poorly documented.

Methods and Results—

We evaluated data from 4128 patients in the I-PRESERVE trial (Irbesartan in Heart Failure with Preserved Ejection Fraction Study). Multivariable Cox regression models were developed using 58 baseline demographic, clinical, and biological variables to model the primary outcome of all-cause mortality or cardiovascular hospitalization (1505 events), all-cause mortality (881 events), and HF death or hospitalization (716 events). Log N-terminal pro–B-type natriuretic peptide, age, diabetes mellitus, and previous hospitalization for HF were the most powerful factors associated with the primary outcome and with the HF composite. For all-cause mortality, log N-terminal pro–B-type natriuretic peptide, age, diabetes mellitus, and left ventricular EF were the strongest independent factors. Other independent factors associated with poor outcome included quality of life, a history of chronic obstructive lung disease, log neutrophil count, heart rate, and estimated glomerular filtration rate. The models accurately stratified the actual 3-year rate of outcomes from 8.1% to 59.9% (primary outcome) 2.7% to 36.5% (all-cause mortality), and 2.1% to 38.9% (HF composite) for the lowest to highest septiles of predicted risks.

Conclusions—

In a large sample of elderly patients with HF and preserved EF enrolled in I-Preserve, simple clinical, demographic, and biological variables were associated with outcome and identified subgroups at very high and very low risk of events.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00095238.

The Wisconsin Network for Health Research (WiNHR): a statewide, collaborative, multi-disciplinary, research group

In response to the goals of the Wisconsin Partnership Program and the National Institutes of Health (NIH) Initiatives to Improve Healthcare, the Wisconsin Network for Health Research (WiNHR) was formed. As a collaborative, multi-disciplinary statewide research network, WiNHR encourages and fosters the discovery and application of scientific knowledge for researchers and practitioners throughout Wisconsin. The 4 founding institutions--Aurora Health Care/Center for Urban Population Health (CUPH), Gundersen Lutheran Medical Foundation, Marshfield Clinic Research Foundation, and the University of Wisconsin-Madison--representing geographically diverse areas of the state, are optimistic and committed to WiNHR's success. This optimism is based on the relevance of its goals to public health, the quality of statewide health care research, and, most importantly, the residents of Wisconsin who recognize the value of health research.

Cardiac Resynchronization Therapy Reduces the Risk of Hospitalizations in Patients With Advanced Heart Failure

Background— In the Comparison of Medical Therapy, Pacing and Defibrillation in Heart Failure (COMPANION) trial, 1520 patients with advanced heart failure were assigned in a 1:2:2 ratio to optimal pharmacological therapy or optimal pharmacological therapy plus cardiac resynchronization therapy (CRT-P) or CRT with defibrillator (CRT-D). Use of CRT-P and CRT-D was associated with a significant reduction in combined risk of death or all-cause hospitalizations. Because mortality also was significantly reduced (optimal pharmacological therapy versus CRT-D only), an assessment of the true reduction in hospitalization rates must consider the competing risk of death and varying follow-up times.

Methods and Results— To overcome the challenges of comparing treatment groups, we used a nonparametric test of right-censored recurrent events that accounts for multiple hospital admissions, differential follow-up time between treatment groups, and death as a competing risk. An end-point committee adjudicated and classified all hospitalizations. Compared with optimal pharmacological therapy, CRT-P and CRT-D were associated with a 21% and 25% reduction in all-cause, 34% and 37% reduction in cardiac, and 44% and 41% reduction in heart failure hospital admissions per patient-year of follow-up, respectively. Similar reductions were seen in hospitalization days per patient-year. The reduction in hospitalization rate for heart failure in the CRT groups appeared within days of randomization and remained sustained. Noncardiac hospitalization rates were not different between groups.

Conclusion— Use of CRT with or without a defibrillator in advanced heart failure patients was associated with marked reductions in all-cause, cardiac, and heart failure hospitalization rates in an analysis that accounted for the competing risk of mortality and unequal follow-up time.

Issues in regulatory guidelines for data monitoring committees

As clinical trials have emerged as the major research method for evaluating new interventions, the process for monitoring intervention safety and benefit has also evolved. The Data Monitoring Committee (DMC) has become the standard approach to implement this responsibility for many Phase III trials. Recent draft guidelines on the operation of DMCs by the Food and Drug Administration (FDA) have raised issues that need further clarification or discussion, especially for industry sponsored trials. These include, the time when DMCs are needed, the role of the independent statistician to support the DMC, and sponsor participation at DMC meetings. This paper provides an overview of these issues, based on the discussions at the January, 2003 workshop sponsored by Duke Clinical Research Institute.

Phase II trial of perillyl alcohol (NSC 641066) administered daily in patients with metastatic androgen independent prostate cancer

OBJECTIVE

We conducted a phase II multicenter trial of perillyl alcohol in patients with advanced hormone refractory prostate cancer (HRPC). The primary endpoint was to evaluate the 6-month progression-free survival given the potential cytostatic nature of the drug. Secondary objectives included assessing acute and chronic toxicities, as well as measuring objective response rates.

METHODS

Patients with metastatic androgen-independent prostate cancer that failed at least one prior chemotherapeutic or experimental regimen were eligible. Perillyl alcohol was administered orally at 1200 mg/m2/dose four times daily and continued until disease progression or development of unacceptable toxicity.

RESULTS

Fifteen patients were eligible. Six patients received less than one cycle (4 weeks) of drug, four of which stopped because of drug intolerance. Only six patients received more than two cycles of therapy and were considered evaluable for response. Main toxicity included grade 1-2 gastrointestinal intolerance (nausea/vomiting in 60% of the patients) and fatigue (47%). One patient developed a grade 4 hypokalemia that was felt likely attributable to the drug. No objective responses were seen. All patients either progressed or withdrew from the study secondary to drug intolerance before the 6-month time period.

CONCLUSION

Perillyl alcohol administered at this dose and formulation did not have any objective clinical activity in this patient population.

Cardiac-resynchronization therapy with or without an implantable defibrillator in advanced chronic heart failure

BACKGROUND

We tested the hypothesis that prophylactic cardiac-resynchronization therapy in the form of biventricular stimulation with a pacemaker with or without a defibrillator would reduce the risk of death and hospitalization among patients with advanced chronic heart failure and intraventricular conduction delays.

METHODS

A total of 1520 patients who had advanced heart failure (New York Heart Association class III or IV) due to ischemic or nonischemic cardiomyopathies and a QRS interval of at least 120 msec were randomly assigned in a 1:2:2 ratio to receive optimal pharmacologic therapy (diuretics, angiotensin-converting-enzyme inhibitors, beta-blockers, and spironolactone) alone or in combination with cardiac-resynchronization therapy with either a pacemaker or a pacemaker-defibrillator. The primary composite end point was the time to death from or hospitalization for any cause.

RESULTS

As compared with optimal pharmacologic therapy alone, cardiac-resynchronization therapy with a pacemaker decreased the risk of the primary end point (hazard ratio, 0.81; P=0.014), as did cardiac-resynchronization therapy with a pacemaker-defibrillator (hazard ratio, 0.80; P=0.01). The risk of the combined end point of death from or hospitalization for heart failure was reduced by 34 percent in the pacemaker group (P<0.002) and by 40 percent in the pacemaker-defibrillator group (P<0.001 for the comparison with the pharmacologic-therapy group). A pacemaker reduced the risk of the secondary end point of death from any cause by 24 percent (P=0.059), and a pacemaker-defibrillator reduced the risk by 36 percent (P=0.003).

CONCLUSIONS

In patients with advanced heart failure and a prolonged QRS interval, cardiac-resynchronization therapy decreases the combined risk of death from any cause or first hospitalization and, when combined with an implantable defibrillator, significantly reduces mortality.

University of Wisconsin IAIMS planning: organizational challenges within a faculty governance model

The University of Wisconsin-Madison Health Sciences Schools are currently in the planning stage of developing an Integrated Advanced Information Management System (IAIMS). The planning phase of this project attends to the unique opportunities that are found at the flagship campus of a large state university system. Statewide teaching and research initiatives and accelerated campus-level capital development challenge the planners to create an IAIMS plan that anticipates an emerging health science environment. Additionally, UW-Madison has an organizational culture with a strong tradition of faculty governance, which provides a very desirable and flexible decision-making environment for a cross-discipline collaborative information management initiative. Development of a shared IAIMS vision conflicts with a governance model that most directly supports intradepartmental decision-making. The challenge presented here for an IAIMS initiative has less to do with hard wiring a technical infrastructure and more to do with increased stakeholder cooperation in a highly decentralized organization with autonomous information systems.

Approached to monitoring the results of long-term disease prevention trials: examples from the Women's Health Initiative

We contrast monitoring therapeutic trials with monitoring prevention trails. We argue that in monitoring prevention trials one should place more emphasis on formally defined global measures of health, not simply on a single targeted disease, particularly when an intervention may reduce the incidence of some diseases but increase the incidence of others. We describe one approach, illustrated by the Women's Health Initiative. For each of several sets of hypothetical interim results ("scenarios"), members of the Data and Safety Monitoring Committee (DSMC) were asked whether they would continue or stop the trial. In parallel with this exercise, various statistical methods of monitoring that are based on (1) the primary targeted disease, (2) a combination of various disease outcomes, or (3) a mixture of both were applied to these scenarios. One objective was to find a statistical approach that mirrors the majority view of the DSMC. A second objective was to stimulate discussion among DSMC members in preparation for their task of monitoring the trial as the real data become available. We found that no single method fully matched the majority vote of the DSMC. However, a mixed approach requiring the primary outcome to be significant and the global index to be "supportive," with separate monitoring of adverse effects, corresponded with the majority vote quite well. This approach maintains the emphasis on the primary hypothesis while assuring that broader safety and ethical issues of multiple diseases are incorporated.