The ixCELL-DCM Trial: Rationale and Design

Abstract

Ixmyelocel-T is an investigational patient-specific, expanded, multicellular therapy produced from a patient's own bone marrow. It is produced by selectively expanding two key types of bone marrow mononuclear cells (BM-MNCs), CD90⁺ mesenchymal stem cells (MSCs), and CD45⁺CD14⁺ autofluorescent, alternatively activated macrophages. Earlier clinical trials suggested that intramyocardial ixmyelocel-T might improve clinical, functional, symptomatic, and quality of life outcomes in patients with ischemic dilated cardiomyopathy (IDCM). This ongoing randomized, double-blinded, placebo-controlled phase 2b trial (ixCELL-DCM) was designed to assess the efficacy, safety, and tolerability of catheter-based transendocardial injection of ixmyelocel-T in patients with heart failure due to IDCM. Patients (N = 114) with New York Heart Association class III or IV symptomatic heart failure due to IDCM, who have left ventricular ejection fraction ≤35% and an automatic implantable cardioverter defibrillator, but are ineligible for revascularization procedures, were randomly assigned (1:1 ratio) to ixmyelocel-T or placebo (vehicle control). The primary efficacy endpoint is a composite of the total number of deaths, cardiovascular hospitalizations, or unplanned clinic visits to treat acutely decompensated heart failure during the 12 months following treatment administration. Secondary endpoints include the win ratio analysis for hierarchical occurrences of clinical events in the primary endpoint, total numbers of clinical events, left ventricular structure and function, and quality-of-life assessments. ixCELL-DCM is one of the largest cell therapy trials in heart failure patients to date and the first double-blinded, placebo-controlled study of ixmyelocel-T administered via transendocardial catheter-based injections in patients with heart failure secondary to IDCM.