Evaluate the Safety and Efficacy of Allogeneic Umbilical Cord Mesenchymal Stem Cells in Patients With Multiple Sclerosis

This study is testing whether infusions of umbilical cord-derived mesenchymal stem cells can safely reduce relapses and slow disability progression in people with relapsing-remitting or secondary progressive multiple sclerosis (MS) who have not responded well to standard MS medications. **You may be eligible if...** - You are 20–65 years old with a confirmed diagnosis of relapsing-remitting MS (RRMS) or secondary progressive MS (SPMS) - Your MS was diagnosed 2–15 years ago, and your disability score (EDSS) is between 2.0 and 6.5 - You have had at least one relapse, new brain lesion, or worsening disability despite being on an approved MS disease-modifying therapy for more than 6 months - Your blood clotting function is normal **You may NOT be eligible if...** - You are pregnant - You are unwilling to use contraception after treatment Talk to your doctor to see if this trial is right for you.