Transplantation of Mesenchymal Stromal Cells in Patients With Amyotrophic Lateral Sclerosis: Results of Phase I/IIa Clinical Trial

Abstract

Amyotrophic lateral sclerosis (ALS) is a progressive untreatable neurodegenerative disorder, leading to the death of the cortical and spinal motoneurons (MNs). Bone marrow-derived mesenchymal stem/stromal cells (BM-MSCs) may represent a new approach to slowing down the progression of ALS by providing neurotrophic support to host MNs and by having an anti-inflammatory effect. We have designed a prospective, nonrandomized, open-label clinical trial (phase I/IIa, EudraCT No. 2011-000362-35) to assess the safety and efficacy of autologous multipotent BM-MSCs in ALS treatment. Autologous BM-MSCs were isolated and expanded under GMP conditions. Patients received 15 ± 4.5 × 106 of BM-MSCs via lumbar puncture into the cerebrospinal fluid. Patients were monitored for 6 months before treatment and then for an 18-month follow-up period. Potential adverse reactions were assessed, and the clinical outcome was evaluated by the ALS functional rating scale (ALSFRS), forced vital capacity (FVC), and weakness scales (WSs) to assess muscle strength on the lower and upper extremities. In total, 26 patients were enrolled in the study and were assessed for safety; 23 patients were suitable for efficacy evaluation. After intrathecal BM-MSC application, about 30% of the patients experienced a mild to moderate headache, resembling the headaches after a standard lumbar puncture. No suspected serious adverse reactions (SUSAR) were observed. We found a reduction in ALSFRS decline at 3 months after application (p < 0.02) that, in some cases, persisted for 6 months ( p < 0.05). In about 80% of the patients, FVC values remained stable or above 70% for a time period of 9 months. Values of WS were stable in 75% of patients at 3 months after application. Our results demonstrate that the intrathecal application of BM-MSCs in ALS patients is a safe procedure and that it can slow down progression of the disease.

Figures

Figure 1.

Clinical analysis of amyotrophic lateral sclerosis (ALS) patients. (A) Regression analysis of ALS functional rating scale (ALSFRS) changes in 23 patients analyzed for efficacy compared to the preimplantation ALSFRS score. Note the significant reduction/stabilization in ALSFRS decline at 3 months after bone marrow-derived mesenchymal stem cell (BM-MSC) application (p < 0.02), which was less pronounced at 6 months (p < 0.05). The y-axis shows the ALSFRS scores, and the x-axis shows the clinical trial visits with corresponding time courses in months. (B) Regression analysis of patients with a decline of ALSFRS scores 6 months before BM-MSC application. (C) Time courses of ALSFRS scores in the individual patients. Patient No. 11 is shown in a separate inset for better visibility of data. (D) Table of the ALSFRS scores.