CellProthera announced that the results from its EXCELLENT Phase I/IIb trial of ProtheraCytes® have now been published in JACC: Heart Failure, offering the first peer-reviewed evidence on the therapy’s safety and feasibility in patients with severe heart failure following myocardial infarction.
The randomized, open-label study enrolled 49 patients across sites in France and the UK. Of these, 33 received transendocardial injections of autologous, expanded CD34+ cells (ProtheraCytes) in addition to standard care, while 16 received only standard care. The average left ventricular ejection fraction at baseline was approximately 35 percent. The trial was not powered to assess efficacy, but early trends in cardiac function markers were observed.
According to the company, treated patients showed a 9 percent average reduction in left ventricular end-systolic volume index, a ~50 percent reduction in severely damaged myocardium at six months, and a 70 percent mean drop in NT-proBNP levels at three months. No deaths or adverse drug reactions were reported. Over six months, one (3 percent) of the treated patients required hospitalization for heart failure, compared with three (19 percent) in the control group, one of whom later underwent transplant. Nine procedure-related complications occurred in the treatment arm, all of which resolved.
The company claims that its automated expansion platform consistently yielded ProtheraCytes with over 90 percent purity and nearly 98 percent viability. Cells were delivered fresh to catheterization labs in France and the UK within hours for same-day administration.
Moving forward, CellProthera intends to launch larger and longer studies to validate these early signals, evaluate long-term outcomes, and further refine procedural safety.
