Yazan Daaboul

Prevention of Bleeding in Patients with Atrial Fibrillation Undergoing PCI

BACKGROUND In patients with atrial fibrillation undergoing percutaneous coronary intervention (PCI) with placement of stents, standard anticoagulation with a vitamin K antagonist plus dual antiplatelet therapy (DAPT) with a P2Y12 inhibitor and aspirin reduces the risk of thrombosis and stroke but increases the risk of bleeding. The effectiveness and safety of anticoagulation with rivaroxaban plus either one or two antiplatelet agents are uncertain. METHODS We randomly assigned 2124 participants with nonvalvular atrial fibrillation who had undergone PCI with stenting to receive, in a 1:1:1 ratio, low-dose rivaroxaban (15 mg once daily) plus a P2Y12 inhibitor for 12 months (group 1), very-low-dose rivaroxaban (2.5 mg twice daily) plus DAPT for 1, 6, or 12 months (group 2), or standard therapy with a dose-adjusted vitamin K antagonist (once daily) plus DAPT for 1, 6, or 12 months (group 3). The primary safety outcome was clinically significant bleeding (a composite of major bleeding or minor bleeding according to Thrombolysis in Myocardial Infarction [TIMI] criteria or bleeding requiring medical attention). RESULTS The rates of clinically significant bleeding were lower in the two groups receiving rivaroxaban than in the group receiving standard therapy (16.8% in group 1, 18.0% in group 2, and 26.7% in group 3; hazard ratio for group 1 vs. group 3, 0.59; 95% confidence interval [CI], 0.47 to 0.76; P<0.001; hazard ratio for group 2 vs. group 3, 0.63; 95% CI, 0.50 to 0.80; P<0.001). The rates of death from cardiovascular causes, myocardial infarction, or stroke were similar in the three groups (Kaplan-Meier estimates, 6.5% in group 1, 5.6% in group 2, and 6.0% in group 3; P values for all comparisons were nonsignificant). CONCLUSIONS In participants with atrial fibrillation undergoing PCI with placement of stents, the administration of either low-dose rivaroxaban plus a P2Y12 inhibitor for 12 months or very-low-dose rivaroxaban plus DAPT for 1, 6, or 12 months was associated with a lower rate of clinically significant bleeding than was standard therapy with a vitamin K antagonist plus DAPT for 1, 6, or 12 months. The three groups had similar efficacy rates, although the observed broad confidence intervals diminish the surety of any conclusions regarding efficacy. (Funded by Janssen Scientific Affairs and Bayer Pharmaceuticals; PIONEER AF-PCI ClinicalTrials.gov number, NCT01830543 .).

EMBRACE STEMI study: a Phase 2a trial to evaluate the safety, tolerability, and efficacy of intravenous MTP-131 on reperfusion injury in patients undergoing primary percutaneous coronary intervention

AIMS Among patients with ST-elevation myocardial infarction (STEMI), reperfusion injury contributes to additional myocardial damage. MTP-131 is a cell-permeable peptide that preserves the integrity of cardiolipin, enhances mitochondrial energetics, and improves myocyte survival during reperfusion. METHODS AND RESULTS EMBRACE STEMI is a multicentre, randomized, double-blind Phase 2a trial that evaluated the efficacy and safety of MTP-131 vs. placebo infused at a rate of 0.05 mg/kg/h for 1 h among first-time anterior STEMI subjects undergoing primary percutaneous coronary intervention (PCI) for a proximal or mid left anterior descending (LAD) artery occlusion. Administration of MTP-131 was not associated with a significant reduction in the primary endpoint, infarct size by creatine kinase-myocardial band (CK-MB) area under the curve (AUC) over 72 h (5785 ± 426 ng h/mL in placebo vs. 5570 ± 486 ng h/mL in MTP-131; ITALIC! P = NS). MTP-131 was not associated with an improvement in pre-specified magnetic resonance imaging, angiographic, electrocardiographic, or clinical outcomes. CONCLUSION Among subjects with first-time anterior STEMI due to a proximal or mid LAD lesion who undergo successful PCI, administration of MTP-131 was safe and well tolerated. Treatment with MTP-131 was not associated with a decrease in myocardial infarct size as assessed by AUC0-72 of CK-MB.

Recurrent Hospitalization Among Patients With Atrial Fibrillation Undergoing Intracoronary Stenting Treated With 2 Treatment Strategies of Rivaroxaban or a Dose-Adjusted Oral Vitamin K Antagonist Treatment Strategy.

Background: Patients with atrial fibrillation who undergo intracoronary stenting traditionally are treated with a vitamin K antagonist (VKA) plus dual antiplatelet therapy (DAPT), yet this treatment leads to high risks of bleeding. We hypothesized that a regimen of rivaroxaban plus a P2Y12 inhibitor monotherapy or rivaroxaban plus DAPT could reduce bleeding and thereby have a favorable impact on all-cause mortality and the need for rehospitalization. Methods: Stented subjects with nonvalvular atrial fibrillation (n=2124) were randomized 1:1:1 to administration of reduced-dose rivaroxaban 15 mg daily plus a P2Y12 inhibitor for 12 months (group 1); rivaroxaban 2.5 mg twice daily with stratification to a prespecified duration of DAPT of 1, 6, or 12 months (group 2); or the reference arm of dose-adjusted VKA daily with a similar DAPT stratification (group 3). The present post hoc analysis assessed the end point of all-cause mortality or recurrent hospitalization for an adverse event, which was further classified as the result of bleeding, a cardiovascular cause, or another cause blinded to treatment assignment. Results: The risk of all-cause mortality or recurrent hospitalization was 34.9% in group 1 (hazard ratio=0.79; 95% confidence interval, 0.66–0.94; P=0.008 versus group 3; number needed to treat=15), 31.9% in group 2 (hazard ratio=0.75; 95% confidence interval, 0.62–0.90; P=0.002 versus group 3; number needed to treat=10), and 41.9% in group 3 (VKA+DAPT). Both all-cause death plus hospitalization potentially resulting from bleeding (group 1=8.6% [P=0.032 versus group 3], group 2=8.0% [P=0.012 versus group 3], and group 3=12.4%) and all-cause death plus rehospitalization potentially resulting from a cardiovascular cause (group 1=21.4% [P=0.001 versus group 3], group 2=21.7% [P=0.011 versus group 3], and group 3=29.3%) were reduced in the rivaroxaban arms compared with the VKA arm, but other forms of rehospitalization were not. Conclusions: Among patients with atrial fibrillation undergoing intracoronary stenting, administration of either rivaroxaban 15 mg daily plus P2Y12 inhibitor monotherapy or 2.5 mg rivaroxaban twice daily plus DAPT was associated with a reduced risk of all-cause mortality or recurrent hospitalization for adverse events compared with standard-of-care VKA plus DAPT. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01830543.

Safety and Tolerability of CSL112, a Reconstituted, Infusible, Plasma-Derived Apolipoprotein A-I, After Acute Myocardial Infarction: The AEGIS-I Trial (ApoA-I Event Reducing in Ischemic Syndromes I)

Background: Human or recombinant apolipoprotein A-I (apoA-I) has been shown to increase high-density lipoprotein–mediated cholesterol efflux capacity and to regress atherosclerotic disease in animal and clinical studies. CSL112 is an infusible, plasma-derived apoA-I that has been studied in normal subjects or those with stable coronary artery disease. This study aimed to characterize the safety, tolerability, pharmacokinetics, and pharmacodynamics of CSL112 in patients with a recent acute myocardial infarction. Methods: The AEGIS-I trial (Apo-I Event Reducing in Ischemic Syndromes I) was a multicenter, randomized, double-blind, placebo-controlled, dose-ranging phase 2b trial. Patients with myocardial infarction were stratified by renal function and randomized 1:1:1 to CSL112 (2 g apoA-I per dose) and high-dose CSL112 (6 g apoA-I per dose), or placebo for 4 consecutive weekly infusions. Coprimary safety end points were occurrence of either a hepatic safety event (an increase in alanine transaminase >3 times the upper limit of normal or an increase in total bilirubin >2 times the upper limit of normal) or a renal safety event (an increase in serum creatinine >1.5 times the baseline value or a new requirement for renal replacement therapy). Results: A total of 1258 patients were randomized, and 91.2% received all 4 infusions. The difference in incidence rates for an increase in alanine transaminase or total bilirubin between both CSL112 arms and placebo was within the protocol-defined noninferiority margin of 4%. Similarly, the difference in incidence rates for an increase in serum creatinine or a new requirement for renal replacement therapy was within the protocol-defined noninferiority margin of 5%. CSL112 was associated with increases in apoA-I and ex vivo cholesterol efflux similar to that achieved in patients with stable coronary artery disease. In regard to the secondary efficacy end point, the risk for the composite of major adverse cardiovascular events among the groups was similar. Conclusions: Among patients with acute myocardial infarction, 4 weekly infusions of CSL112 are feasible, well tolerated, and not associated with any significant alterations in liver or kidney function or other safety concern. The ability of CSL112 to acutely enhance cholesterol efflux was confirmed. The potential benefit of CSL112 to reduce major adverse cardiovascular events needs to be assessed in an adequately powered phase 3 trial. Clinical Trial Registration: URL: https://clinicaltrials.gov. Unique identifier: NCT02108262.

Extended-Duration Betrixaban Reduces the Risk of Stroke Versus Standard-Dose Enoxaparin Among Hospitalized Medically Ill Patients: An APEX Trial Substudy (Acute Medically Ill Venous Thromboembolism Prevention With Extended Duration Betrixaban).

Background: Stroke is a morbid and potentially mortal complication among patients hospitalized with acute medical illness. The potential of extended-duration thromboprophylaxis with the factor Xa inhibitor betrixaban to reduce the risk of stroke compared with standard-dose enoxaparin in this population was assessed in this retrospective APEX trial substudy (Acute Medically Ill Venous Thromboembolism Prevention With Extended Duration Betrixaban). Methods: Hospitalized acutely medically ill subjects (n=7513) were randomized in a double-dummy double-blind fashion to either extended-duration oral betrixaban (80 mg once daily for 35–42 days) or standard-dose subcutaneous enoxaparin (40 mg once daily for 10±4 days) for venous thromboprophylaxis. Stroke events were adjudicated by an independent, blinded event adjudication committee. Results: The mean age of study participants was 76 years; 45% were male; 13% had had a stroke; and 45% had congestive heart failure. There were fewer all-cause strokes (0.54% versus 0.97%; relative risk [RR]=0.56; 95% confidence interval, 0.32–0.96; P=0.032; adjusted RR=0.43%; number needed to treat=233) and ischemic strokes (0.48% versus 0.91%; RR=0.53; 95% confidence interval, 0.30–0.94; P=0.026; adjusted RR=0.43%; number needed to treat=233) among patients treated with betrixaban versus enoxaparin through 77 days of follow-up. Among high-risk subjects, those with congestive heart failure or ischemic stroke as their index event, betrixaban reduced the risk of all-cause stroke (0.72% versus 1.48%; RR=0.49; 95% confidence interval, 0.26–0.90; P=0.019; adjusted RR=0.76%; number needed to treat=132) and ischemic stroke (0.63% versus 1.38%; RR=0.45; 95% confidence interval, 0.24–0.87; P=0.014; adjusted RR=0.75%; number needed to treat=134) compared with enoxaparin. Conclusions: Among hospitalized medically ill patients, extended-duration betrixaban significantly reduced all-cause stroke and ischemic stroke through 77 days of follow-up Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01583218.

The safety and efficacy of full- versus reduced-dose betrixaban in the Acute Medically Ill VTE (Venous Thromboembolism) Prevention With Extended-Duration Betrixaban (APEX) trial

Background The APEX trial assessed the safety and efficacy of extended‐duration thromboprophylaxis using betrixaban versus standard dosing of enoxaparin among hospitalized, acutely ill medical patients. The 80‐mg betrixaban dose was halved to 40 mg among subjects with severe renal insufficiency and those receiving a concomitant strong P‐glycoprotein inhibitor. Methods This analysis assessed the pharmacokinetics, efficacy, and safety of full‐ (80 mg) and reduced‐dose (40 mg) betrixaban relative to enoxaparin in the APEX trial. Results The median concentration of betrixaban among subjects administered the 80‐mg dose was higher than that of the 40‐mg dose (19 ng/mL vs 11 ng/mL, P < .001). In the primary analysis cohort 1 (d‐dimer ≥2× upper limit of normal), the primary efficacy outcome (asymptomatic proximal deep vein thrombosis, symptomatic proximal or distal deep vein thrombosis, symptomatic nonfatal pulmonary embolism, or venous thromboembolism–related death) was significantly reduced among subjects treated with 80 mg of extended‐duration betrixaban versus enoxaparin (6.27% [95/1516] vs 8.39% [130/1549], relative risk reduction = 0.26 [0.04‐0.42], P = .023), and similarly in the entire primary efficacy outcome population (4.87% [122/2506] vs 7.06% [181/2562], relative risk reduction = 0.30 [0.13‐0.44], P = .001). There was no difference in the primary outcome for subjects treated with 40 mg betrixaban vs enoxaparin across cohorts. In addition, there was no excess of major bleeding associated with either betrixaban dose compared with enoxaparin. Conclusions The 80‐mg betrixaban dose achieves higher plasma concentrations than the 40‐mg dose and, in contrast to the 40‐mg dose, is associated with improved efficacy across all cohorts relative to standard‐dose enoxaparin without an excess risk of major bleeding in the management of medically ill subjects.

D-Dimer elevation and adverse outcomes.

Abstractd-Dimer is a biomarker of fibrin formation and degradation. While a d-dimer within normal limits is used to rule out the diagnosis of deep venous thrombosis and pulmonary embolism among patients with a low clinical probability of venous thromboembolism (VTE), the prognostic association of an elevated d-dimer with adverse outcomes has received far less emphasis. An elevated d-dimer is independently associated with an increased risk for incident VTE, recurrent VTE, and mortality. An elevated d-dimer is an independent correlate of increased mortality and subsequent VTE across a broad variety of disease states. Therefore, medically ill subjects in whom the d-dimer is elevated constitute a high risk subgroup in which the prospective evaluation of the efficacy and safety of antithrombotic therapy is warranted.

Rationale and design of Apo-I Event Reduction in Ischemic Syndromes I (AEGIS-I): A phase 2b, randomized, placebo-controlled, dose-ranging trial to investigate the safety and tolerability of CSL112, a reconstituted, infusible, human apoA-I, after acute myocardial infarction

BACKGROUND Despite aggressive pharmacotherapy and stenting, there is a residual risk of major adverse cardiovascular events among patients with acute coronary syndrome. High-density lipoprotein (HDL) has been a major target for secondary acute coronary syndrome prevention; however, a better understanding of the physiologic function of HDL has demonstrated that a high cholesterol efflux capacity, rather than high HDL concentrations alone, may be critical to improving outcomes. CSL112, a reconstituted, infusible human apolipoprotein A-I, has been demonstrated to increase cholesterol efflux capacity and to have a protective effect in experimental models of atherosclerotic cardiovascular disease. DESIGN The AEGIS-I trial (ClinicalTrials.govNCT02108262) is a phase 2b, multicenter, randomized, placebo-controlled, dose-ranging clinical trial to evaluate the hepatic and renal safety of multiple administrations of 2 doses of CSL112 among subjects with acute myocardial infarction (AMI). Approximately 1,200 subjects (400 per treatment group) with either normal renal function or mild renal impairment will be enrolled up to 7 days after an AMI and will be stratified by renal function and randomized in a 1:1:1 ratio to either 1 of 2 doses of CSL112 (either 2 g or 6 g) or placebo as a weekly 2-hour infusion over the course of 4 consecutive weeks. The coprimary safety endpoints will be the incidence of hepatic and renal toxicity, defined as either confirmed ALT >3 × ULN, total bilirubin >2 × ULN, serum creatinine ≥1.5×baseline value, or a new requirement for renal replacement therapy through the end of the active treatment period. SUMMARY The AEGIS-I trial will characterize the safety profile of CSL112, a reconstituted formulation of apolipoprotein A-I, and will assess if administration to patients with a recent AMI is associated with a clinically significant alteration in either liver or kidney function when compared with placebo.

The IMPROVEDD VTE Risk Score: Incorporation of D-Dimer into the IMPROVE Score to Improve Venous Thromboembolism Risk Stratification

Background  The IMPROVE score is a validated venous thromboembolism (VTE) assessment tool to risk stratify hospitalized, medically ill patients based on clinical variables. It was hypothesized that addition of D-dimer measurement to derive a new IMPROVEDD score would improve identification of at risk of VTE. Methods  The association of the IMPROVE score and D-dimer ≥ 2 × the upper limit of normal (ULN) with the risk of symptomatic deep vein thrombosis, nonfatal pulmonary embolism, or VTE-related death was evaluated in 7,441 hospitalized, medically ill patients randomized in the APEX trial. Based on the Cox regression analysis, the IMPROVEDD score was derived by adding two points to the IMPROVE score if the D-dimer was ≥ 2 × ULN. Results  Baseline D-dimer was independently associated with symptomatic VTE through 77 days (adjusted HR: 2.22 [95% CI: 1.38–1.58], p  = 0.001). Incorporation of D-dimer into the IMPROVE score improved VTE risk discrimination (ΔAUC: 0.06 [95% CI: 0.02–0.09], p  = 0.0006) and reclassification (continuous NRI: 0.34 [95% CI: 0.17–0.51], p  = 0.001; categorical NRI: 0.13 [95% CI: 0.03–0.23], p  = 0.0159). Patients with an IMPROVEDD score of ≥2 had a greater VTE risk compared with those with an IMPROVEDD score of 0 to 1 (HR: 2.73 [95% CI: 1.52–4.90], p  = 0.0007). Conclusion  Incorporation of D-dimer into the IMPROVE VTE risk assessment model further improves risk stratification in hospitalized, medically ill patients who received thromboprophylaxis. An IMPROVEDD score of ≥2 identifies hospitalized, medically ill patients with a heightened risk for VTE through 77 days.

Comparison of Fatal or Irreversible Events With Extended-Duration Betrixaban Versus Standard Dose Enoxaparin in Acutely Ill Medical Patients: An APEX Trial Substudy.

Background Extended‐duration betrixaban showed a significant reduction in venous thromboembolism in the APEX trial (Acute Medically Ill VTE Prevention With Extended Duration Betrixaban Study). Given the variable clinical impact of different efficacy and safety events, one approach to assess net clinical outcomes is to include only those events that are either fatal or cause irreversible harm. Methods and Results This was a post hoc analysis of the APEX trial—a multicenter, double‐blind, randomized controlled trial comparing extended‐duration betrixaban versus standard‐of‐care enoxaparin. A composite of all fatal or irreversible safety (fatal bleeding or intracranial hemorrhage) and efficacy events (cardiopulmonary death, myocardial infarction, pulmonary embolism, and ischemic stroke) was evaluated in a time‐to‐first event analysis. In patients with positive D‐dimer results, betrixaban reduced fatal or irreversible events at 35 to 42 days (4.80% versus 3.54%; hazard ratio, 0.73; absolute risk reduction, 1.26%; number needed to treat, 79 [P=0.033]) and at study end at 77 days (6.27% versus 4.36%; hazard ratio, 0.70; absolute risk reduction, 1.91%; number needed to treat, 52 [P=0.005]) versus enoxaparin. In all patients, betrixaban reduced fatal or irreversible events at 35 to 42 days (4.08% versus 2.90%; hazard ratio, 0.71; absolute risk reduction, 1.18%; number needed to treat, 86 [P=0.006]) and 77 days (5.17% versus 3.64%; hazard ratio, 0.70; absolute risk reduction, 1.53%; number needed to treat, 65 [P=0.002]). Conclusions Among hospitalized medically ill patients, extended‐duration betrixaban demonstrated an ≈30% reduction in fatal or irreversible ischemic or bleeding events compared with standard‐duration enoxaparin. A total of 65 patients would require treatment with betrixaban to prevent 1 fatal or irreversible event versus enoxaparin. Clinical Trial Registration URL: http://www.ClinicalTrials.gov. Unique identifier: NCT01583218.