Results from International Phase II Clinical Trial on the Use of Mesenchymal Stem Cells for People with Multiple Sclerosis
The international multi-site clinical trial on the use of MEsenchymal StEm cells for Multiple Sclerosis (MESEMS) reported that mesenchymal stem cells (MSC) could be harvested and grown, and were safe and well tolerated in people with MS. However, in this trial, researchers were unable to demonstrate that MSC treatment was effective at reducing inflammatory activity in individuals with active relapsing-remitting or progressive MS, as defined by recent relapses and/or evidence of MRI activity.
According to the study results published in Lancet Neurology, treatment with MSC did not show a statistically significant effect on the total number of gadolinium-enhancing lesions after 24 weeks from baseline, the primary outcome of the study that aimed to measure acute inflammation in people with active relapsing-remitting, primary and secondary progressive MS. MSC treatment also did not show a significant effect on secondary outcomes, including MRI (e.g., total volume of gadolinium-enhancing and T2w lesions, total number of combined unique active lesions, difference in volume of T1w hypointense lesions) and clinical measures (e.g., Symbol Digit Modalities Test and Expanded Disability Status Scale (EDSS) scores) at 24 weeks. The researchers observed a decreasing trend in the Annualized Relapse Rate (i.e. reduced number of relapses) of those treated with MSC, but this did not reach statistical significance. No difference in serious adverse events between MSC-treated and placebo control groups were reported indicating that the treatment was safe.
Despite the negative results of this trial, MSC have demonstrated neuroprotective and ‘tissue healing’ properties in other studies involving preclinical models of MS, and other neurological disorders. Hence, further evidence is needed to assess the efficacy of MSC treatment to understand whether they can repair tissue to reduce disease worsening and prevent disability progression.
MESEMS is the first large, multi-centre, randomized, double-blind, placebo-controlled Phase II trial to assess the safety and efficacy of intravenously administered bone marrow-derived MSC in patients with active MS. Unlike the previously conducted autologous hematopoietic stem cell transplantation (AHSCT) trial, participants in the MESEMS trial did not require intensive chemotherapy in order to reboot the overactive immune system. Instead, MSC treatment represented a lower risk treatment option that was hypothesized to work by subduing the harmful immune cells that drive MS, and promote internal repair. The study enrolled 144 eligible participants with relapsing-remitting MS who were unresponsive to existing MS therapies, as well as select individuals with primary and secondary progressive forms of MS that still showed evidence of active disease with new MRI lesions or recent attacks. Participants were assessed for side effects as well as any potential clinical benefits of MSC therapy, including reduced brain inflammation, number of relapses, disability progression and other indicators of potential repair in the central nervous system.
The study was performed by a large team of international researchers and clinicians across fifteen sites and ten countries. MESCAMS (MEsenchymal StEm cell therapy for CAnadian MS patients) is the Canadian arm of the international MESEMS clinical trial. MESCAMS is led by Dr. Mark S. Freedman (The Ottawa Hospital and University of Ottawa Brain and Mind Research Institute) and Dr. James Marriott (Health Sciences Centre Winnipeg and University of Manitoba). For additional information, visit the following: MESCAMS study, FAQ and Fact Sheet.
People with MS should be cautious about seeking any stem cell treatment without scientific evidence for their effect. If you have questions regarding stem cell treatments, please contact your health care team for more information.
To access the MESEMS scientific article, please click here.