Safety and outcomes analysis: transcatheter implantation of autologous angiogenic cell precursors for the treatment of cardiomyopathy

Abstract

Background: Stem cell transplantation is an emerging therapy for severe cardiomyopathy, proffering stem cell recruitment, anti-apoptosis, and proangiogenic capabilities. Angiogenic cell precursors (ACP-01) are autologous, lineage-specific, cells derived from a multipotent progenitor cell population, with strong potential to effectively engraft, form blood vessels, and support tissue survival and regeneration.

Methods: This IRB approved outcome analysis reports upon 74 consecutive patients who failed medical management for severe cardiomyopathy, and were selected to undergo transcatheter intramyocardial or intracoronary implantation of ACP-01. Serious adverse events (SAEs) were reported. Cell analysis was conducted for each treatment. The left ventricular ejection fraction (LVEF) was measured by multi-gated acquisition scan (MUGA) or echocardiogram at 4 months ± 1.9 months and 12 months ± 5.5 months. Patients reported quality of life statements at 6 months (± 5.6 months).

Results: Fifty-four of 74 patients met requirements for inclusion (48 males and five females; age 68.1 ± 11.3 years). The mean treatment cell number of 57 × 10⁶ ACP-01 included 7.7 × 10⁶ CD34 + and 21 × 10⁶ CD31 + cells with 97.6% viability. SAEs included one death (previously unrecognized silent MI), ventricular tachycardia (n = 2) requiring cardioversion, and respiratory infection (n = 2). LVEF in the ischemic subgroup (n = 41) improved by 4.7% ± 9.7 from pre-procedure to the first follow-up (4 months ± 1.9 months) (p < 0.004) and by 7.2% ± 10.9 at final follow-up (n = 25) at average 12 months (p < 0.004). The non-ischemic dilated cardiomyopathy subgroup (n = 8) improved by 7.5% ± 6.0 at the first follow-up (p < 0.017) and by 12.2% ± 6.4 at final follow-up (p < 0.003, n = 6). Overall improvement in LVEF from pre-procedure to post-procedure was significant (Fisher's exact test p < 0.004). LVEF improvement was most marked in the patients with the most severe cardiomyopathy (LVEF < 20%) improving from a mean 14.6% ± 3.4% pre-procedurally to 28.4% ± 8% at final follow-up. Quality of life statements reflected improvement in 33/50 (66%), no change in 14/50 (28%), and worse in 3/50 (6%).

Conclusion: Transcatheter implantation of ACP-01 for cardiomyopathy is safe and improves LVEF in the setting of ischemic and non-ischemic cardiomyopathy. The results warrant further investigation in a prospective, blinded, and controlled clinical study.

Trial registration: IRB from Genetic Alliance #APC01-001, approval date July 25, 2022. Cardiomyopathy is common and associated with high mortality. Stem cell transplantation is an emerging therapy. Angiogenic cell precursors (ACP-01) are lineage-specific endothelial progenitors, with strong potential for migration, engraftment, angiogenesis, and support of tissue survival and regeneration. A retrospective outcomes analysis of 53 patients with ischemic and non-ischemic dilated cardiomyopathy undergoing transcatheter implantation of ACP-01 demonstrated improvements in the left ventricular ejection fraction of 7.2% ± 10.9 (p < 0.004) and 12.2% ± 6.4, respectively, at 12 months (± 5) follow-up. Quality of life statements reflected improvement in 33/50 (66%) patients.

Keywords: Angiogenesis; Angiogenic stem cell; Angiogenin; Anti-apoptosis; Autologous hematopoietic stem cell; Cardiomyopathy; Cytokine IL-8; NF-kB; VEGF.