The purpose of this study is to analyze the potential clinical efficacy of intrathecal administration, in the subarachnoid space, of in vitro expanded autologous adult bone marrow mesenchymal stem cells in the treatment of patients with established chronic spinal cord injury (LEM).

This is a clinical trial phase II, single-center, non-randomized, uncontrolled, open prospective follow-up of a cohort of patients with chronic spinal cord injury.

Patients are treated with repeated administrations of in vitro expanded autologous adult bone marrow mesenchymal stem cells.

The expanded cells are administered in the subarachnoid space by lumbar puncture. The minimum duration of the follow-up period for each patient is 10 months after the first administration.

The study duration is 24 months, that include recruiting, treatment and follow period for all patients. For each patient at the first day will be administered the first cellular doses, then 3 doses will be administrated every 3 months. At the end of the clinical trial, a completed check of all obtained parameters will be performed.

It is considered Day 1 for each patient the first day of the first cell administration. The remaining 2 doses will be administered at intervals of 3 months from the first administration (of the treatment period after, months 4 and 7). At the end of the study will be performed a full assessment of the variables collected along the study trial.

Inclusion Criteria:

1. Spinal cord injury (Level A, B, C or D in ASIA scales), clinically stable for at least 6 months prior to study start.
2. Previous studies of Neurophysiology, MRI and Urology to allow useful baseline, in order that they can be compared with the same scans following treatment, and to obtain objective data of potential efficacy.
3. Age between 18 and 70 years.
4. Men and women of childbearing age must compromise to use contraceptives from the time at which the removal of cells from the bone marrow is performed until 6 months after the Mesenchymal Stem Cells (MSC) last administration by lumbar puncture.
5. Possibility of follow up and ability to perform ambulatory physical therapy throughout all treatment period.
6. Written informed consent, according to the law in force.
7. Hematologic, creatinine, Serum glutamic oxaloacetic transaminase (SGOT) and Serum glutamic pyruvic transaminase (SGPT) parameters, within the normal range, according to laboratory standards. However, slight modifications that are considered significant in the context of treatment to be performed, according to the criterion of the research team, are accepted.

Exclusion Criteria:

1. Age below 18 years or above 70.
2. Pregnancy or lactation.
3. Current neoplastic disease or in the previous 5 years (diagnosed or treated).
4. Patients with systemic disease that represents an added risk to treatment.
5. Alterations in the genetic study performed to discard risk cell transformation in the expansion process.
6. Patients with doubts about possible cooperation in the maintenance physical therapy or in the controls carried out during the study
7. Neurodegenerative disease added.
8. History of substance abuse, psychiatric disease or allergy to protein products used in the process of cell expansion.
9. Positive serology for HIV and syphilis.
10. Active Hepatitis B or Hepatitis C, according to serology analysis.
11. If in the opinion of the researcher there is some other reason why the patient is not considered candidate for the study.

Anonymized individual data of participants will be shared with Authorities at the end of the Clinical development plan by the CTD (Common Technical Document). Results will be published in a scientific publication

Starting at CTD submission to authorities.

Spanish competent authority.