Background Medical Therapy and Clinical Outcomes From the VICTORIA Trial.

BACKGROUND: We examined whether the primary composite outcome (cardiovascular death or heart failure hospitalization) was related to differences in background use and dosing of guideline-directed medical therapy in patients with heart failure with reduced ejection fraction enrolled in VICTORIA (Vericiguat Global Study in Subjects with Heart Failure with Reduced Ejection Fraction), a randomized trial of vericiguat versus placebo. METHODS: We evaluated the adherence to guideline use of angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, angiotensin receptor-neprilysin inhibitors, beta-blockers, and mineralocorticoid receptor antagonists. We assessed basic adherence; indication-corrected adherence accounting for guideline indications and contraindications; and dose-corrected adherence (indication-corrected adherence+≥50% of drug dose target). Associations between study treatment and the primary composite outcome according to the adherence to guidelines were assessed using multivariable adjustment; adjusted hazard ratios with 95% CIs and Pinteraction are reported. RESULTS: Of 5050 patients, 5040 (99.8%) had medication data at baseline. For angiotensin-converting enzyme inhibitor, angiotensin-receptor blockers, and angiotensin receptor-neprilysin inhibitors, basic adherence to guidelines was 87.4%, indication-corrected was 95.7%, and dose-corrected was 50.9%. For beta-blockers, basic adherence was 93.1%, indication-corrected was 96.2%, and dose-corrected was 45.4%. For mineralocorticoid receptor antagonists, basic adherence was 70.3%, indication-corrected was 87.1%, and dose-corrected was 82.2%. For triple therapy (angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, or angiotensin receptor-neprilysin inhibitors+beta-blocker+mineralocorticoid receptor antagonist), basic adherence was 59.7%, indication-corrected was 83.3%, and dose-corrected was 25.5%. Using basic or dose-corrected adherence, the treatment effect of vericiguat was consistent across adherence to guidelines groups, with or without multivariable adjustment with no treatment heterogeneity. CONCLUSIONS: Patients in VICTORIA were well treated with heart failure with reduced ejection fraction medications. The efficacy of vericiguat was consistent across background therapy with very high adherence to guidelines accounting for patient-level indications, contraindications, and tolerance. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02861534.

Phase 3 Trial of Sotatercept for Treatment of Pulmonary Arterial Hypertension.

BACKGROUND: Pulmonary arterial hypertension is a progressive disease involving proliferative remodeling of the pulmonary vessels. Despite therapeutic advances, the disease-associated morbidity and mortality remain high. Sotatercept is a fusion protein that traps activins and growth differentiation factors involved in pulmonary arterial hypertension. METHODS: We conducted a multicenter, double-blind, phase 3 trial in which adults with pulmonary arterial hypertension (World Health Organization [WHO] functional class II or III) who were receiving stable background therapy were randomly assigned in a 1:1 ratio to receive subcutaneous sotatercept (starting dose, 0.3 mg per kilogram of body weight; target dose, 0.7 mg per kilogram) or placebo every 3 weeks. The primary end point was the change from baseline at week 24 in the 6-minute walk distance. Nine secondary end points, tested hierarchically in the following order, were multicomponent improvement, change in pulmonary vascular resistance, change in N-terminal pro-B-type natriuretic peptide level, improvement in WHO functional class, time to death or clinical worsening, French risk score, and changes in the Pulmonary Arterial Hypertension-Symptoms and Impact (PAH-SYMPACT) Physical Impacts, Cardiopulmonary Symptoms, and Cognitive/Emotional Impacts domain scores; all were assessed at week 24 except time to death or clinical worsening, which was assessed when the last patient completed the week 24 visit. RESULTS: A total of 163 patients were assigned to receive sotatercept and 160 to receive placebo. The median change from baseline at week 24 in the 6-minute walk distance was 34.4 m (95% confidence interval [CI], 33.0 to 35.5) in the sotatercept group and 1.0 m (95% CI, -0.3 to 3.5) in the placebo group. The Hodges-Lehmann estimate of the difference between the sotatercept and placebo groups in the change from baseline at week 24 in the 6-minute walk distance was 40.8 m (95% CI, 27.5 to 54.1; P<0.001). The first eight secondary end points were significantly improved with sotatercept as compared with placebo, whereas the PAH-SYMPACT Cognitive/Emotional Impacts domain score was not. Adverse events that occurred more frequently with sotatercept than with placebo included epistaxis, dizziness, telangiectasia, increased hemoglobin levels, thrombocytopenia, and increased blood pressure. CONCLUSIONS: In patients with pulmonary arterial hypertension who were receiving stable background therapy, sotatercept resulted in a greater improvement in exercise capacity (as assessed by the 6-minute walk test) than placebo. (Funded by Acceleron Pharma, a subsidiary of MSD; STELLAR ClinicalTrials.gov number, NCT04576988.).

Medical Therapy During Hospitalization for Heart Failure With Reduced Ejection Fraction: The VICTORIA Registry.

BACKGROUND: For patients hospitalized for heart failure with reduced ejection fraction (HFrEF), guidelines recommend optimization of medical therapy prior to discharge. The degree to which changes in medical therapy occur during hospitalizations for HFrEF in North American clinical practice is unclear. METHODS: The VICTORIA registry (Vericiguat Global Study in Subjects with Heart Failure with Reduced Ejection Fraction) enrolled patients hospitalized for worsening chronic HFrEF across 51 sites in the United States and Canada from February 2018-January 2019. In patients with complete medication data who were not receiving dialysis, use and dose of angiotensin-converting enzyme inhibitor (ACEI)/angiotensin II receptor blocker (ARB), angiotensin receptor neprilysin inhibitor (ARNI), beta-blocker, mineralocorticoid receptor antagonist (MRA), and sodium glucose cotransporter-2 inhibitors (SGLT2i) were assessed at admission and discharge. RESULTS: Of 1695 patients, the median (IQR) age was 69 (59-79) years, and 33% were women. Among eligible patients, 33%, 25% and 55% were not prescribed ACEI/ARB/ARNI, beta-blocker, and MRA at discharge, respectively; 99% were not prescribed SGLT2i. For each medication, > 50% of patients remained on stable subtarget doses or no medication during hospitalization. In-hospital rates of initiation/dose increase were 20% for ACEI/ARB, 4% for ARNI, 20% for beta-blocker, 22% for MRA, and < 1% for SGLT2i; corresponding rates of dose decrease/discontinuation were 11%, 2%, 9%, 5%, and < 1%, respectively. Overall, 17% and 28% of eligible patients were prescribed triple therapy prior to admission and at discharge, respectively. At both admission and discharge, 1% of patients were prescribed triple therapy at target doses. Across classes of medication, multiple factors were independently associated with higher likelihood of in-hospital initiation/dosing increase (eg, Canadian enrollment, white race, admission to intensive care units) and discontinuation/dosing decrease (eg, worse renal function, admission to intensive care units). CONCLUSIONS: In this contemporary North American registry of patients hospitalized for worsening chronic HFrEF, for each recommended medical therapy, the large majority of eligible patients remained on stable subtarget doses or without medication at admission and discharge. Although most patients had no alterations in medical therapy, hospitalization in Canada and multiple patient characteristics were associated with higher likelihood of favorable in-hospital medication changes.

Renal function and the effects of vericiguat in patients with worsening heart failure with reduced ejection fraction: insights from the VICTORIA (Vericiguat Global Study in Subjects with HFrEF) trial.

AIMS: Vericiguat reduced the primary composite outcome of cardiovascular death or heart failure (HF) hospitalization in patients with worsening HF with reduced ejection fraction (HFrEF) and a lower limit of baseline estimated glomerular filtration rate (eGFR) of 15 mL/min/1.73 m2 . We evaluated the relationship between the efficacy of vericiguat and baseline and subsequent changes in renal function. METHODS AND RESULTS: In VICTORIA, core laboratory serum creatinine was measured at baseline (n = 4956) and weeks 16, 32, and 48. Worsening renal function (WRF), defined as an increase ≥0.3 mg/dL in creatinine from baseline to week 16, was assessed via a Cox model with respect to subsequent primary events. Mean age was 69 years, 24% were female, and mean baseline eGFR was 61 mL/min/1.73 m2 . During 48 weeks of treatment, the trajectories in eGFR and creatinine with vericiguat were similar to placebo (P = 0.50 and 0.18). The beneficial effects of vericiguat on the primary outcome were not influenced by baseline eGFR (interaction P = 0.48). WRF occurred in 15% of patients and was associated with worse outcomes (adjusted hazard ratio 1.28, 95% confidence interval 1.11-1.47; P < 0.001), but the beneficial effects of vericiguat on the primary outcome were similar in patients with or without WRF (interaction P = 0.76). CONCLUSION: Renal function trajectories were similar between vericiguat- and placebo-treated patients and the beneficial effects of vericiguat on the primary outcome were consistent across the full range of eGFR and irrespective of WRF.

Vericiguat in Patients with Heart Failure and Reduced Ejection Fraction.

BACKGROUND: The effect of vericiguat, a novel oral soluble guanylate cyclase stimulator, in patients with heart failure and reduced ejection fraction who had recently been hospitalized or had received intravenous diuretic therapy is unclear. METHODS: In this phase 3, randomized, double-blind, placebo-controlled trial, we assigned 5050 patients with chronic heart failure (New York Heart Association class II, III, or IV) and an ejection fraction of less than 45% to receive vericiguat (target dose, 10 mg once daily) or placebo, in addition to guideline-based medical therapy. The primary outcome was a composite of death from cardiovascular causes or first hospitalization for heart failure. RESULTS: Over a median of 10.8 months, a primary-outcome event occurred in 897 of 2526 patients (35.5%) in the vericiguat group and in 972 of 2524 patients (38.5%) in the placebo group (hazard ratio, 0.90; 95% confidence interval [CI], 0.82 to 0.98; P = 0.02). A total of 691 patients (27.4%) in the vericiguat group and 747 patients (29.6%) in the placebo group were hospitalized for heart failure (hazard ratio, 0.90; 95% CI, 0.81 to 1.00). Death from cardiovascular causes occurred in 414 patients (16.4%) in the vericiguat group and in 441 patients (17.5%) in the placebo group (hazard ratio, 0.93; 95% CI, 0.81 to 1.06). The composite of death from any cause or hospitalization for heart failure occurred in 957 patients (37.9%) in the vericiguat group and in 1032 patients (40.9%) in the placebo group (hazard ratio, 0.90; 95% CI, 0.83 to 0.98; P = 0.02). Symptomatic hypotension occurred in 9.1% of the patients in the vericiguat group and in 7.9% of the patients in the placebo group (P = 0.12), and syncope occurred in 4.0% of the patients in the vericiguat group and in 3.5% of the patients in the placebo group (P = 0.30). CONCLUSIONS: Among patients with high-risk heart failure, the incidence of death from cardiovascular causes or hospitalization for heart failure was lower among those who received vericiguat than among those who received placebo. (Funded by Merck Sharp & Dohme [a subsidiary of Merck] and Bayer; VICTORIA ClinicalTrials.gov number, NCT02861534.).

Baseline features of the VICTORIA (Vericiguat Global Study in Subjects with Heart Failure with Reduced Ejection Fraction) trial.

AIM: Describe the distinguishing features of heart failure (HF) patients with reduced ejection fraction (HFrEF) in the VICTORIA (Vericiguat Global Study in Patients with Heart Failure with Reduced Ejection Fraction) trial. METHODS AND RESULTS: Key background characteristics were evaluated in 5050 patients randomized in VICTORIA and categorized into three cohorts reflecting their index worsening HF event. Differences within the VICTORIA population were assessed and compared with PARADIGM-HF (Prospective comparison of ARNI with ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure) and COMMANDER HF (A Study to Assess the Effectiveness and Safety of Rivaroxaban in Reducing the Risk of Death, Myocardial Infarction, or Stroke in Participants with Heart Failure and Coronary Artery Disease Following an Episode of Decompensated Heart Failure). VICTORIA patients had increased risk of mortality and rehospitalization: New York Heart Association class (40% class III), atrial fibrillation (45%), diabetes (47%), hypertension (79%) and mean estimated glomerular filtration rate of 61.5 mL/min/1.73 m2 . Baseline standard of HF care was very good: 60% received triple therapy. Their N-terminal pro-B-type natriuretic peptide was 3377 pg/mL [interquartile range (IQR) 1992-6380]. Natriuretic peptides were 30% higher level in the 67% patients with HF hospitalization <3 months, compared to those within 3-6 months of HF hospitalization and those randomized after recent outpatient intravenous diuretic therapy. Overall the median MAGGIC (Meta-Analysis Global Group in Chronic Heart Failure) risk score in VICTORIA was 23 (IQR 18-27) as compared to the MAGGIC risk score in PARADIGM-HF of 20 (IQR 16-24). CONCLUSIONS: VICTORIA comprises a broadly generalizable high-risk population of three unique clinical strata of worsening chronic HFrEF despite very good HF therapy. VICTORIA will establish the role of vericiguat, a soluble guanylate cyclase stimulator, in HFrEF.

A Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial of the Efficacy and Safety of the Oral Soluble Guanylate Cyclase Stimulator: The VICTORIA Trial.

This trial sought to evaluate whether vericiguat, a novel oral soluble guanylate cyclase (sGC) stimulator, was superior to placebo, on a background of standard of care, in increasing the time to the first occurrence of the composite endpoints of cardiovascular (CV) death and heart failure (HF) hospitalization in patients with HF with reduced ejection fraction (HFrEF). Deficiency in sGC-derived cyclic guanosine monophosphate (cGMP) causes both myocardial dysfunction and impaired endothelium-dependent vasomotor regulation that includes the myocardial microcirculation. Experimental studies have suggested multiple potential benefits of sGC stimulators including prevention, or even reversal, of left ventricular hypertrophy and fibrosis, as well as reduction of ventricular afterload through both systemic and pulmonary vasodilation. Hence, restoration of sufficient nitric oxide (NO)-sGC-cGMP signaling has been proposed as an important treatment target in HF. Vericiguat has been shown to directly stimulate sGC and enhance sGC sensitivity to endogenous NO. Available phase IIb data in HFrEF patients indicate vericiguat is safe and well-tolerated, and exploratory analyses indicate that it results in a dose-dependent, clinically significant reduction in N-terminal pro-B-type natriuretic peptide (NT-proBNP) at the highest tested dose. VICTORIA (Vericiguat Global Study in Subjects With Heart Failure With Reduced Ejection Fraction) is a randomized, placebo-controlled, parallel group, multicenter, double-blind, event-driven phase 3 trial of vericiguat in subjects with HFrEF. Approximately 4,872 subjects will be randomized to evaluate the efficacy and safety of vericiguat compared with placebo on a background of standard of care. After a screening phase of up to 30 days, eligible subjects will be treated until the required number of cardiovascular deaths is observed. The estimated median follow-up duration is approximately 18 months. All subjects will be followed until study completion to assess for the occurrence of endpoint events. VICTORIA will establish the efficacy and safety of vericiguat on cardiovascular death and HF hospitalization in patients with HFrEF. (A Randomized Parallel-Group, Placebo-Controlled, Double-Blind, Event-Driven, Multi-Center Pivotal Phase III Clinical Outcome Trial of Efficacy and Safety of the Oral sGC Stimulator Vericiguat in Subjects With Heart Failure With Reduced Ejection Fraction [HFrEF]-VerICiguaT Global Study in Subjects With Heart Failure With Reduced Ejection Fraction [VICTORIA]; NCT02861534).

Reassessing Phase II Heart Failure Clinical Trials: Consensus Recommendations.

The increasing burden and the continued suboptimal outcomes for patients with heart failure underlines the importance of continued research to develop novel therapeutics for this disorder. This can only be accomplished with successful translation of basic science discoveries into direct human application through effective clinical trial design and execution that results in a substantially improved clinical course and outcomes. In this respect, phase II clinical trials play a pivotal role in determining which of the multitude of potential basic science discoveries should move to the large and expansive registration trials in humans. A critical examination of the phase II trials in heart failure reveals multiple shortcomings in their concept, design, execution, and interpretation. To further a dialogue on the challenges and potential for improvement and the role of phase II trials in patients with heart failure, the Food and Drug Administration facilitated a meeting on October 17, 2016, represented by clinicians, researchers, industry members, and regulators. This document summarizes the discussion from this meeting and provides key recommendations for future directions.

Association Between Sitagliptin Use and Heart Failure Hospitalization and Related Outcomes in Type 2 Diabetes Mellitus: Secondary Analysis of a Randomized Clinical Trial.

IMPORTANCE: Previous trial results have suggested that dipeptidyl peptidase 4 inhibitor (DPP4i) use might increase heart failure (HF) risk in type 2 diabetes mellitus (T2DM). The DPP4i sitagliptin has been shown to be noninferior to placebo with regard to primary and secondary composite atherosclerotic cardiovascular (CV) outcomes in the Trial Evaluating Cardiovascular Outcomes With Sitagliptin (TECOS). OBJECTIVE: To assess the association of sitagliptin use with hospitalization for HF (hHF) and related outcomes. DESIGN, SETTING, AND PARTICIPANTS: TECOS was a randomized, double-blind, placebo-controlled study evaluating the CV safety of sitagliptin vs placebo, each added to usual antihyperglycemic therapy and CV care among patients with T2DM and prevalent atherosclerotic vascular disease. The median follow-up was 2.9 years. The setting was 673 sites in 38 countries. Participants included 14 671 patients with T2DM and atherosclerotic vascular disease. The study dates were December 2008 through March 2015. INTERVENTIONS: Patients were randomized to sitagliptin vs placebo added to standard care. MAIN OUTCOMES AND MEASURES: Prespecified secondary analyses compared the effect on hHF, hHF or CV death, and hHF or all-cause death composite outcomes overall and in prespecified subgroups. Supportive analyses included total hHF events (first plus recurrent) and post-hHF death. Meta-analyses evaluated DPP4i effects on hHF and on hHF or CV death. RESULTS: Of 14 671 patients, 7332 were randomized to sitagliptin and 7339 to placebo. Hospitalization for HF occurred in 3.1% (n = 228) and 3.1% (n = 229) of the sitagliptin and placebo groups, respectively (unadjusted hazard ratio, 1.00; 95% CI, 0.83-1.19). There was also no difference in total hHF events between the sitagliptin (n = 345) and placebo (n = 347) groups (unadjusted hazard ratio, 1.00; 95% CI, 0.80-1.25). Post-hHF all-cause death was similar in the sitagliptin and placebo groups (29.8% vs 28.8%, respectively), as was CV death (22.4% vs 23.1%, respectively). No heterogeneity for the effect of sitagliptin on hHF was observed in subgroup analyses across 21 factors (P > .10 for all interactions). Meta-analysis of the hHF results from the 3 reported DPP4i CV outcomes trials revealed moderate heterogeneity (I2 = 44.9, P = .16). CONCLUSIONS AND RELEVANCE: Sitagliptin use does not affect the risk for hHF in T2DM, both overall and among high-risk patient subgroups. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00790205.

Effect of Sitagliptin on Cardiovascular Outcomes in Type 2 Diabetes.

BACKGROUND: Data are lacking on the long-term effect on cardiovascular events of adding sitagliptin, a dipeptidyl peptidase 4 inhibitor, to usual care in patients with type 2 diabetes and cardiovascular disease. METHODS: In this randomized, double-blind study, we assigned 14,671 patients to add either sitagliptin or placebo to their existing therapy. Open-label use of antihyperglycemic therapy was encouraged as required, aimed at reaching individually appropriate glycemic targets in all patients. To determine whether sitagliptin was noninferior to placebo, we used a relative risk of 1.3 as the marginal upper boundary. The primary cardiovascular outcome was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina. RESULTS: During a median follow-up of 3.0 years, there was a small difference in glycated hemoglobin levels (least-squares mean difference for sitagliptin vs. placebo, -0.29 percentage points; 95% confidence interval [CI], -0.32 to -0.27). Overall, the primary outcome occurred in 839 patients in the sitagliptin group (11.4%; 4.06 per 100 person-years) and 851 patients in the placebo group (11.6%; 4.17 per 100 person-years). Sitagliptin was noninferior to placebo for the primary composite cardiovascular outcome (hazard ratio, 0.98; 95% CI, 0.88 to 1.09; P<0.001). Rates of hospitalization for heart failure did not differ between the two groups (hazard ratio, 1.00; 95% CI, 0.83 to 1.20; P=0.98). There were no significant between-group differences in rates of acute pancreatitis (P=0.07) or pancreatic cancer (P=0.32). CONCLUSIONS: Among patients with type 2 diabetes and established cardiovascular disease, adding sitagliptin to usual care did not appear to increase the risk of major adverse cardiovascular events, hospitalization for heart failure, or other adverse events. (Funded by Merck Sharp & Dohme; TECOS ClinicalTrials.gov number, NCT00790205.).

Clinical Development Approaches and Statistical Methodologies to Prospectively Assess the Cardiovascular Risk of New Antidiabetic Therapies for Type 2 Diabetes.

In December 2008, the US Food and Drug Administration (FDA) issued a guidance for industry requiring sponsors to demonstrate that a new antidiabetic therapy being developed to treat type 2 diabetes does not increase cardiovascular (CV) risk to an unacceptable extent. CV events reported during phase 2 and phase 3 trials should be prospectively and independently adjudicated. Before submission of a new drug application or biologics license application, sponsors should compare the incidence of major CV events occurring with the investigational agent versus the control group to show that the upper bound of the 2-sided 95% confidence interval (CI) for the estimated risk ratio is less than 1.8. If the CI includes 1.3, a postmarketing trial will be necessary to definitively show that the upper bound of the 95% CI for the estimated risk ratio is then less than 1.3. In 2012, the European Medicines Agency (EMA) issued an updated guideline on the clinical investigation of medicinal products in the treatment or prevention of diabetes mellitus that detailed its CV safety assessment requirements. Although similar to the FDA guidance, the EMA guideline does not prospectively define any pre- or postapproval risk margins. This expert perspective, prepared by members of the Cardiac Safety Research Consortium, discusses clinical development strategies, operational issues, and statistical methodological issues to satisfy the FDA's CV safety requirements, and, where appropriate, the EMA guideline. Actual case examples, where applicable, are presented.

Clinical outcome endpoints in heart failure trials: a European Society of Cardiology Heart Failure Association consensus document.

Endpoint selection is a critically important step in clinical trial design. It poses major challenges for investigators, regulators, and study sponsors, and it also has important clinical and practical implications for physicians and patients. Clinical outcomes of interest in heart failure trials include all-cause mortality, cause-specific mortality, relevant non-fatal morbidity (e.g., all-cause and cause-specific hospitalization), composites capturing both morbidity and mortality, safety, symptoms, functional capacity, and patient-reported outcomes. Each of these endpoints has strengths and weaknesses that create controversies regarding which is most appropriate in terms of clinical importance, sensitivity, reliability, and consistency. Not surprisingly, a lack of consensus exists within the scientific community regarding the optimal endpoint(s) for both acute and chronic heart failure trials. In an effort to address these issues, the Heart Failure Association of the European Society of Cardiology (HFA-ESC) convened a group of expert heart failure clinical investigators, biostatisticians, regulators, and pharmaceutical industry scientists (Nice, France, 12-13 February 2012) to evaluate the challenges of defining heart failure endpoints in clinical trials and to develop a consensus framework. This report summarizes the group's recommendations for achieving common views on heart failure endpoints in clinical trials.

Is thrombosis a contributor to heart failure pathophysiology? Possible mechanisms, therapeutic opportunities, and clinical investigation challenges.

Thrombotic events (coronary thrombosis, venous thromboembolism, intraventricular thrombosis, intracranial and systemic thromboembolism) occur frequently in patients with heart failure. These events may be precipitated by several mechanisms including hypercoagulability through enhancement of procoagulant reactions, impairment of the protein C pathway, protease activated receptor (PAR) activation, adenosine-mediated thrombosis, or neurohormonal activation; stasis secondary to low cardiac output; and endothelial dysfunction from neurohormonal activation or systemic inflammation. Pathophysiologic evidence and analyses of retrospective data support the hypothesis that antithrombotic agents may improve outcomes in patients with heart failure. Warfarin has not been shown to reduce clinical events in patients with heart failure, although several of the completed randomized trials were underpowered, and the most recent was not placebo-controlled. Many unanswered questions remain that justify continued research in this area. This paper examines the conceptual framework, opportunities, and challenges of clinical investigative approaches with the newer anti-thrombotic agents in patients with heart failure. Critical questions are raised with regard to clinical trial designs that warrant consideration as the field progresses.

Effect of adenosine-regulating agent acadesine on morbidity and mortality associated with coronary artery bypass grafting: the RED-CABG randomized controlled trial.

CONTEXT: Ischemia/reperfusion injury remains an important cause of morbidity and mortality after coronary artery bypass graft (CABG) surgery. In a meta-analysis of randomized controlled trials, perioperative and postoperative infusion of acadesine, a first-in-class adenosine-regulating agent, was associated with a reduction in early cardiac death, myocardial infarction, and combined adverse cardiac outcomes in participants undergoing on-pump CABG surgery. OBJECTIVE: To assess the efficacy and safety of acadesine administered in the perioperative period in reducing all-cause mortality, nonfatal stroke, and severe left ventricular dysfunction (SLVD) through 28 days. DESIGN, SETTING, AND PARTICIPANTS: The Reduction in Cardiovascular Events by Acadesine in Patients Undergoing CABG (RED-CABG) trial, a randomized, double-blind, placebo-controlled, parallel-group evaluation of intermediate- to high-risk patients (median age, 66 years) undergoing nonemergency, on-pump CABG surgery at 300 sites in 7 countries. Enrollment occurred from May 6, 2009, to July 30, 2010. INTERVENTIONS: Eligible participants were randomized 1:1 to receive acadesine (0.1 mg/kg per minute for 7 hours) or placebo (both also added to cardioplegic solutions) beginning just before anesthesia induction. MAIN OUTCOME MEASURE: Composite of all-cause mortality, nonfatal stroke, or need for mechanical support for SLVD during and following CABG surgery through postoperative day 28. RESULTS: Because results of a prespecified futility analysis indicated a very low likelihood of a statistically significant efficacious outcome, the trial was stopped after 3080 of the originally projected 7500 study participants were randomized. The primary outcome occurred in 75 of 1493 participants (5.0%) in the placebo group and 76 of 1493 (5.1%) in the acadesine group (odds ratio, 1.01 [95% CI, 0.73-1.41]). There were no differences in key secondary end points measured. CONCLUSION: In this population of intermediate- to high-risk patients undergoing CABG surgery, acadesine did not reduce the composite of all-cause mortality, nonfatal stroke, or SLVD. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00872001.

Carotid atherosclerosis progression in familial hypercholesterolemia patients: a pooled analysis of the ASAP, ENHANCE, RADIANCE 1, and CAPTIVATE studies.

BACKGROUND: Until recently, patients with heterozygous familial hypercholesterolemia (HeFH) were considered the best subjects for the assessment of changes in carotid intima-media thickness (cIMT) in randomized intervention trials. Our aims were to investigate whether contemporary statin-treated HeFH patients still show accelerated cIMT increase and to assess the impact of statin treatment, before and after random assignment, on atherosclerosis progression. METHODS AND RESULTS: We retrospectively evaluated cIMT change, and prior statin treatment and postbaseline LDL-C change as predictors of cIMT change, in 1513 HeFH patients who were randomly assigned to the statin arms of the early ASAP and more recent RADIANCE 1, CAPTIVATE, and ENHANCE studies. In the 3 recent studies combined, mean cIMT increased at only 33%of the rate of the simvastatin-treated patients in the ASAP study (0.014 mm/2 years [95% confidence interval, -0.0003-0.028] versus 0.041 mm/2 years [95% confidence interval, 0.020-0.061]; P<0.05). Patients whose statin therapy could be intensified, as evidenced by an LDL-C decrease after the initiation of on-trial statin therapy, showed cIMT decrease in the first 6 to 12 months and a much lower cIMT increase measured over the full 2 years. In line with this, previously statin-naive HeFH patients showed a lower overall cIMT increase. CONCLUSIONS: Over the years, intensification of statin therapy in HeFH patients has resulted in an impressive decrease in carotid atherosclerosis progression. In studies that assess other antiatherosclerotic modalities, statin therapy may still induce rapid changes in cIMT. For future cIMT studies, our analyses suggest that patient populations other than intensively pretreated HeFH patients should be selected and that the statin regimen should not be changed on study initiation.

Effects of sources of variability on sample sizes required for RCTs, applied to trials of lipid-altering therapies on carotid artery intima-media thickness.

OBJECTIVE: Studies measuring progression of carotid artery intima-media thickness (cIMT) have been used to estimate the effect of lipid-modifying therapies cardiovascular event risk. The likelihood that future cIMT clinical trials will detect a true treatment effect is estimated by leveraging results from prior studies. The present analyses assess the impact of between- and within-study variability based on currently published data from prior clinical studies on the likelihood that ongoing or future cIMT trials will detect the true treatment effect of lipid-modifying therapies. METHODS: Published data from six contemporary cIMT studies (ASAP, ARBITER 2, RADIANCE 1, RADIANCE 2, ENHANCE, and METEOR) including data from a total of 3563 patients were examined. Bayesian and frequentist methods were used to assess the impact of between study variability on the likelihood of detecting true treatment effects on 1-year cIMT progression/regression and to provide a sample size estimate that would specifically compensate for the effect of between-study variability. RESULTS: In addition to the well-described within-study variability, there is considerable between-study variability associated with the measurement of annualized change in cIMT. Accounting for the additional between-study variability decreases the power for existing study designs. In order to account for the added between-study variability, it is likely that future cIMT studies would require a large increase in sample size in order to provide substantial probability (> or =90%) to have 90% power of detecting a true treatment effect.Limitation Analyses are based on study level data. Future meta-analyses incorporating patient-level data would be useful for confirmation. CONCLUSION: Due to substantial within- and between-study variability in the measure of 1-year change of cIMT, as well as uncertainty about progression rates in contemporary populations, future study designs evaluating the effect of new lipid-modifying therapies on atherosclerotic disease progression are likely to be challenged by large sample sizes in order to demonstrate a true treatment effect.

Two-year clinical outcomes after paclitaxel-eluting stent or brachytherapy treatment for bare metal stent restenosis: the TAXUS V ISR trial.

AIMS: This study sought to investigate the 2-year outcomes of patients treated with the paclitaxel-eluting TAXUS((R)) stent (PES) or vascular brachytherapy (VBT), the previous 'gold standard therapy', for bare metal stent in-stent restenosis (ISR). METHODS AND RESULTS: In the TAXUS V-ISR trial, 396 patients with bare metal stent ISR referred for percutaneous coronary intervention were prospectively randomized to either PES or beta source VBT. The present analysis reports 24-month clinical outcomes from that study. Between 9 and 24 months, ischaemia-driven target lesion revascularization tended to be required less frequently with assignment to PES compared to VBT (5.3 vs. 10.3%, P = .07). As a result, ischaemia-driven target lesion revascularization at 24 months was significantly reduced with PES compared with VBT (10.1 vs. 21.6%, P = 0.003), as was ischaemia-driven target vessel revascularization (18.1 vs. 27.5%, P = .03). There were no significant differences between the two groups with regard to death, myocardial infarction, or target vessel thrombosis either between 12 and 24 months, or cumulative to 24 months. CONCLUSION: Freedom from clinical restenosis at 2 years is significantly enhanced after PES placement compared with VBT for bare metal stent ISR, with similar rates of death, myocardial infarction, and target vessel thrombosis.

Chronic arterial responses to overlapping paclitaxel-eluting stents: insights from serial intravascular ultrasound analyses in the TAXUS-V and -VI trials.

OBJECTIVES: The purpose of this study was to use intravascular ultrasound (IVUS) to investigate chronic arterial responses at the site of and adjacent to overlapping paclitaxel-eluting TAXUS stents (PES) compared with overlapping bare-metal stents (BMS). BACKGROUND: Increased paclitaxel dose in the PES-overlap region might be associated with arterial toxicity expressed as excessive expansive remodeling, incomplete stent apposition, or aneurysm formation. METHODS: In the TAXUS-V and -VI trials, 51 patients with overlapping stents (27 PES and 24 BMS) were imaged with serial IVUS immediately after procedure and at 9 months. The IVUS measurements included intimal hyperplasia (IH), peri-stent plaque plus media (P&M), and external elastic membrane (EEM) areas. Vascular responses were assessed at the proximal and distal single stent strut regions and the central overlap region. RESULTS: Compared with BMS, all 3 PES stent regions showed: 1) significantly decreased IH (proximal: 0.97 +/- 1.06 mm(2) vs. 3.12 +/- 2.40 mm(2), overlap: 0.74 +/- 0.91 mm(2) vs. 3.23 +/- 1.75 mm(2), distal: 0.88 +/- 0.85 mm(2) vs. 2.69 +/- 1.49 mm(2), all p < 0.05); and 2) increased P&M and EEM areas (Delta P&M, proximal: 0.96 +/- 1.36 mm(2) vs. -0.02 +/- 1.48 mm(2), overlap: 1.56 +/- 1.88 mm(2) vs. 0.29 +/- 1.82 mm(2), distal: 1.03 +/- 1.81 mm(2) vs. 0.11 +/- 0.89 mm(2), all p < 0.05). The IH and changes in EEM and P&M areas were not significantly different in both the BMS and PES groups comparing the single stent strut and overlap regions. Incomplete stent apposition did not occur at the site of overlapping PES in any patient. CONCLUSIONS: Nine months after stent implantation, neointimal tissue growth was reduced and expansive remodeling was greater with PES compared with BMS--effects that were not exaggerated at the overlap region of PES.

TAXUS VI 2-year follow-up: randomized comparison of polymer-based paclitaxel-eluting with bare metal stents for treatment of long, complex lesions.

AIMS: Drug-eluting stents (DESs) have shown to be effective in reducing in-stent restenosis, although data relating to long-term experience in treating more complex lesion subsets are limited. In order to assess the long-term safety and clinical efficacy of the polymer-based moderate release (MR) paclitaxel-eluting TAXUS MR stent in treatment of complex lesion subsets, we evaluated the 2-year follow-up of TAXUS VI. METHOD AND RESULTS: TAXUS VI was a randomized multi-centre study enrolling 446 patients with complex lesions, including small vessels in 28% of patients and a mean lesion length of 20.6 mm. At 9-month follow-up, the use of the TAXUS MR stent was highly effective, resulting in a significant 53% reduction of the target vessel revascularization (TVR) rate (primary endpoint) from 19.4% in the control group to 9.1% in the TAXUS group (P = 0.0027). Clinical follow-up at 2 years post-stenting was available in 98.6% of the TAXUS group and 95.6% of the control group. The incidence of major adverse cardiac event at 1- and 2-year follow-up was 16.4% and 21.3% in the TAXUS group when compared with 22.5 and 25.1% in the control group, respectively. A significant difference in TVR was maintained at 2-year follow-up (TAXUS 13.9%; control 21.9%; P = 0.0335). The cumulative 1- and 2-year survival rates free from TVR were, respectively, 91.7 and 90.3% in the TAXUS group vs. 80.0 and 79.0% in the control group (log-rank P < 0.001). The number of patients required to be treated with a TAXUS stent to prevent one re-percutaneous coronary intervention at 2 years was 12.5. CONCLUSION: Treatment of complex coronary lesions with the polymer-based MR paclitaxel-eluting TAXUS MR stent is associated with a sustained clinical benefit and low rates of TVR up to 2 years after device implantation.

Meta-analysis of angiographic versus intravascular ultrasound parameters of drug-eluting stent efficacy (from TAXUS IV, V, and VI).

Both quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) are currently used to assess in-stent restenosis. This study aimed to use standardized imaging and clinical follow-up to compare QCA parameters with several IVUS parameters to evaluate their strengths and weaknesses for detecting in-stent restenosis in a drug-eluting stent population. A subset of patients from the TAXUS IV, V, and VI studies was evaluated. The subset, which included 216 TAXUS-treated patients and 191 bare-metal stent-treated patients, had complete IVUS and QCA performed at baseline and follow-up. As expected, all QCA and IVUS parameters were consistent with less intimal hyperplasia in TAXUS patients than controls. The overall incidence of QCA binary restenosis was 14.0%, which was 9.3% in TAXUS-treated patients and 19% in bare-metal stent-treated patients (p = 0.0008). Regression analysis showed that QCA late lumen loss and percentage of diameter stenosis correlated only moderately with the various IVUS measures of neointimal hyperplasia for the combined group of patients (TAXUS + bare-metal stent), as well as for the TAXUS-treated and bare-metal stent-treated patients separately. However, in general, correlations within the control (bare-metal stent) group tended to be stronger than within the TAXUS group. The strongest correlation was between QCA percentage of diameter stenosis and IVUS percentage of intimal hyperplasia in the overall group and the control group. The strongest IVUS predictor of QCA binary restenosis at 9 months was maximum percentage of intimal hyperplasia, with an overall C = 0.91 and p <0.001. In conclusion, the QCA and IVUS parameters used to evaluate drug-eluting stent efficacy showed a moderate correlation with IVUS percentage of intimal hyperplasia, reliably predicting QCA binary in-stent restenosis.