Long-Term Clinical Outcomes Survey of Bone Marrow-Derived Cell Therapy in Critical Limb Ischemia in Japan

BACKGROUND: The Therapeutic Angiogenesis by Cell Transplantation (TACT) trial demonstrated the efficacy and safety of autologous bone marrow-derived mononuclear cells (BM-MNCs) in patients with critical limb ischemia (CLI). The present study aimed to assess the long-term clinical outcomes of therapeutic angiogenesis using autologous BM-MNC implantation under advanced medical treatment in Japan. METHODS AND RESULTS: The study was retrospective, observational, and non-controlled. We assessed no-option CLI patients who had BM-MNC implantation performed in 10 institutes. Overall survival (OS), major amputation-free (MAF), and amputation-free survival (AFS) rates were primary endpoints of this study. The median follow-up duration was 31.7 months. The 10-year OS rate was 46.6% in patients with arteriosclerosis obliterans (ASO) (n=168), 90.5% in patients with thromboangiitis obliterans (TAO) (n=108), and 67.6% in patients with collagen disease-associated vasculitis (CDV) (n=69). The 10-year MAF rate was 70.1%, 87.9%, and 90.9%, respectively. The 10-year AFS rate was 37.8%, 80.9%, and 61.2%, respectively. Major adverse cardiovascular events occurred in 6.0% of patients with ASO, 1.9% of patients with TAO, and no patients with CDV. CONCLUSIONS: Therapeutic angiogenesis using autologous BM-MNC implantation may be feasible and safe in patients with no-option CLI, particularly those with CLI caused by TAO or CDV.