Transendocardial ProtheraCytes injections improved physical functioning and vitality in patients with recent large AMI and LV dysfunction.

Percutaneous autologous expanded CD34⁺ cell therapy (ProtheraCytes) has demonstrated feasibility, manageable safety concerns and a regenerative potential in the EXCELLENT phase I/IIb trial (NCT02669810). Objective of our study was to assess HRQoL over 6 months following ProtheraCytes therapy in patients with recent large AMI and left ventricular (LV) dysfunction. EXCELLENT was a multicenter, randomized, open-label, controlled phase I/IIb trial enrolling 77 AMI patients. Participants were randomized 3:1 to standard-of-care (SoC) plus transendocardial ProtheraCytes injections or SoC alone. The per-protocol population included 49 subjects. Of those, 31 treated and 12 control patients were analyzable with complete baseline and follow-up 36-Item Short Form Survey (SF-36) data. HRQoL domains and composite scores were analyzed using repeated-measures ANCOVA adjusted for baseline values. At baseline, HRQoL was markedly impaired, consistent with severe LV dysfunction (mean physical functioning score at 63.3, LVEF 35.2%, elevated NT-proBNP). At 6 months, the treated group showed significant and sustained meaningful improvements in physical functioning (+ 16.6 PF, p = 0.0002), vitality (+ 12.7 VT, p = 0.0072), social functioning (+ 17.9 SF, p = 0.0059), and bodily pain (+ 17.0 BP, p = 0.0031). Between months 3 and 6, most HRQoL domains declined in controls but remained stable or improved in treated patients. In conclusion, ProtheraCytes therapy was associated with significant HRQoL gains sustained over 6 months, alongside biological improvements. These findings support further evaluation of expanded CD34⁺ cell therapy to address the unmet need for durable functional recovery post-AMI.