A Phase I/IIa, Randomized, Double-blind, Single-dose, Placebo Controlled, Two-way Crossover Clinical Trial to Assess the Safety and to Obtain Efficacy Data in Intrathecal Administration of Expanded Wharton's Jelly Mesenchymal Stem Cells in Chronic Traumatic Spinal Cord Injury

This is a phase I/IIa, randomized, double-blind, two-arms, two-dose administration, placebo controlled, clinical trial in which 10 patients from 18 to 65 years of age affected with chronic traumatic spinal cord will enter the study with the objective to assess the safety and to obtain efficacy data in intrathecal administration (L3 level) of expanded Wharton's jelly mesenchymal stem cells. Following the administration patients will remain for 24 h at the hospital and thereafter will be discharged. For the first period, the follow-up is planned at day 7 and at 1, 3 and 6 months. At month 6, the patients will be treated in a crossover way (second period) and will follow the same schedule for the follow-up. First clinical trial evaluation will be performed at 12 month follow-up. From 12 to 18 month after the first infusion, patients will be randomized again to active treatment or placebo (double-blind) in order to assess the safety and efficacy of a second dose at 12 month follow-up. Thereafter, patients will be followed up at 24 and 36 months as part of a long-term follow-up.