Allogenic Adipose Tissue-derived Mesenchymal Stromal Cells for the Treatment of Primary Progressive Multiple Sclerosis

Inclusion Criteria: * Patient with Primary Progressive MS according to the criteria of Mc Donald 2017 (Thompson et al Lancet neurol, 2017) * Age between 18 and 55 years * EDSS score: 3 to 6 at inclusion * Documented evidence of disability progression independent of relapse activity at any point in time over the 2 years prior to the screening visit * Positive CSF with oligoclonal bands * For women of childbearing potential (WOCBP), effective contraception as per the CFTG recommendations (version 1.1) * Having signed a free, informed and written consent * Affiliated to social security scheme Exclusion Criteria: * Inflammatory activity during the past year (relapses or new T2 MRI lesions) * Disease Modifying Drugs during the past year * Treatment with high dose corticosteroids during the 30 days preceding the inclusion * Contra indication to lumbar puncture/intrathecal infusion: intracranial hypertension, puncture site infections, severe thrombocytopenia (\<50 G/L), anticoagulant or fibrinolytic treatment * Participation in another therapeutic trial in the last 6 months * Adults under legal protection (safeguard of justice, curatorship, guardianship), persons deprived of their liberty, pregnant or breastfeeding women, minors, persons unable to express their consent