ANAKINRA IN THE TREATMENT OF PEDIATRIC ACUTE MYOCARDITIS

Activation of the inflammasome is increasingly recognized in the pathogenesis of acute myocarditis. We hypothesize that by blocking inflammasome using anakinra, we interfere with the key mechanism driving myocardial inflammation and fibrosis, allowing for restauration of myocardial function compared to standard of care alone. Children from ≥ 3 months to \< 18 years of age hospitalized in the Intensive Care Unit for acute myocarditis defined as a reduced left ventricle ejection fraction below 50% and troponin T rise (\>1.5x normal range) will be randomized to either receive SC Anakinra or Placebo in addition to standard of care treatment. Primary endpoint: Proportion of children with recovered left ventricle ejection fraction (LVEF ≥ 50%) measured by echocardiography at 3 days after treatment initiation.

Secondary endpoints:

1. Proportion of children with recovered left ventricle ejection fraction (LVEF

≥ 50%) measured by echocardiography at 7 and 28 days after treatment initiation. Patients who die or undergo heart transplant within the first 7 and 28 days after treatment initiation respectively will be considered as a failure (i.e, LVEF \< 50%). Patients who still require ECMO at 7 and 28 days after treatment initiation respectively will also be considered as failure (i.e., LVEF \< 50%). 2. Time to recovery of normal left ventricular ejection fraction (LVEF ≥ 50%) within the first 3 days after treatment initiation 3. Proportion of children requiring ECMO within the first 3 days after treatment initiation 4. Proportion of children who undergo heart transplant within 6 months after treatment initiation 5. Time to all-cause death within 6 months after treatment initiation 6. Time to cardiovascular-related death within 6 months after treatment initiation 7. Proportion of children with drug-related side effects (hypersensitivity, neutropenia, drug-related liver enzymes elevation…) 8. a- NT proBNP at inclusion and at 24 hours, 48 hours, 72 hours following treatment initiation - Troponin T at inclusion and at 24 hours, 48 hours, 72 hours following treatment initiation - Proportion of children with ventricular tachycardia assessed by EKG at inclusion and at 24 hours, 48 hours, 72 hours following treatment initiation - b - NT proBNP at 7 days following treatment initiation - Troponin T at 7 days following treatment initiation - Proportion of children with ventricular tachycardia assessed by EKG at 7 days following treatment initiation - Proportion of children with fibrosis on cardiac MRI according to modified Lake Louise criteria at 6 months following treatment initiation - Proportion of children with dilated cardiomyopathy on cardiac echocardiography (Left ventricular end diastolic diameter ˃ 2 SD with altered systolic function \<50%) at 3 and 6 months following treatment initiation - Proportion of children with ventricular arrhythmia at 6 months following treatment initiation.

• Proportion of children with recovered left ventricle ejection fraction ≥ 50% measured by echocardiography at 7 and 28 days after treatment initiation. Patients who die or undergo heart transplant within the first 7 and 28 days after treatment initiation [Срок оценки: 7 and 28 days]
• Time to recovery of normal left ventricular ejection fraction (LVEF ≥ 50%) within the first 3 days after treatment initiation [Срок оценки: 3 days]
• Proportion of children requiring ECMO within the first 3 days after treatment initiation [Срок оценки: 3 days]
• Proportion of children who undergo heart transplant within 6 months after treatment initiation [Срок оценки: 6 months]
• Time to all-cause death within 6 months after treatment initiation [Срок оценки: 6 months]
• Time to cardiovascular-related death within 6 months after treatment initiation [Срок оценки: 6 months]
• Proportion of children with drug-related side effects (hypersensitivity, neutropenia, drug-related liver enzymes elevation…) [Срок оценки: 6 months]
• following treatment initiation-TroponinT at inclusion and at24 hours,48 hours,72 hours following treatment initiation-Proportion of children with ventricular tachycardia assessed by EKG at inclusion and at 24hours,48hours,72hours following treatment init [Срок оценки: 24,48,72 hours]
• NTproBNP at7days, Troponin T at7days,Proportion of children with ventricular tachycardia assessed by EKG at7days, Proportion of children with fibros on cardiac MRI at6months,Proportion of children with dilated cardiomyopathy,with ventricular arrhythmia [Срок оценки: 7 days - 3 and 6 months]