Prospective, interventional, randomized, placebo-controlled, cross-over study. Patients are randomized to either treatment arm A or B.~Patients in both treatment arms receive intrathecal autologous MSCs, arm A at baseline and arm B at six months.~All patients undergo bone marrow (BM) aspiration prior to baseline. Patients in treatment arm A receive intrathecal autologous MSCs whereas patients in treatment arm B receive placebo. The treatment is blinded for the patients. The BM aspirate from patients in treatment arm B is processed, cryopreserved and stored in a biobank.~At six months, all patients undergo a second BM aspiration. Patients in treatment arm A now receive placebo. The BM aspirate from patients in treatment arm A is processed, cryopreserved and stored in a biobank. Patients in treatment arm B receive intrathecal autologous MSCs. The treatment is blinded for the patients.~Primary outcome is assessed at six months and secondary outcomes are assessed at six, twelve and eighteen months post baseline. Investigator assessing outcomes are blinded to patient treatment allocation.
The primary objective of the study is to investigate neuroregenerative efficacy (proof of concept) of intrathecal treatment with autologous MSCs as measured by neurophysiological parameters in patients with progressive MS.~Secondary objectives are to assess neuroregenerative efficacy as measured by other neurophysiological parameters as well as clinical, opthalmological and MRI modalities, and to assess safety of the treatment procedure.