Marcus Koch

Multiple Sclerosis: Hydroxychloroquine May Benefit Some Patients with Most Severe Disease Interview with:

Marcus Koch

Dr. Koch

Marcus Koch MD PhD
Associate Professor of Neurology
Multiple Sclerosis Program
University of Calgary What is the background for this study?

Response: Primary progressive multiple sclerosis (PPMS) is the least common, but also the least treatable form of multiple sclerosis. PPMS does not react well to commonly used MS treatments. We believe that this is at least in part because PPMS is driven by other disease mechanisms.

One disease mechanism that we believe is important in PPMS is microglial activation. Microglial cells are a type of cell in the brain and spinal cord that normally have beneficial functions, such as clearing debris or assisting repair after injury. In PPMS however, microglial cells are chronically active, and we believe that this chronic microglial activation contributes to tissue damage. What are the main findings?

Response: Hydroxychloroquine has a powerful calming effect on microglial cells, which made us want to try this medication in people with PPMS. We treated 35 people with PPMS with HCQ for 18 months. We would have expected 40%, or 14 of these 35 people, to experience significant worsening of their walking function during the trial. At the end of the study only 8 people had worsened, which suggests to us that HCQ treatment may have potential in PPMS, and that it should be investigated in further studies. What should readers take away from your report?

 Response: Hydroxychloroquine treatment may be beneficial for the prevention of worsening disability in primary progressive multiple sclerosis, and should be investigated in further controlled clinical studies. What recommendations do you have for future research as a result of this work?

Response: Our study is just the beginning. Hydroxychloroquine treatment in PPMS should be investigated in a larger clinical trial, ideally compared to placebo treatment.

No disclosures


Koch, M.W., Kaur, S., Sage, K., Kim, J., Levesque-Roy, M., Cerchiaro, G., Yong, V.W., Cutter, G.R. and Metz, L.M. (2021), Hydroxychloroquine for Primary Progressive Multiple Sclerosis. Ann Neurol, 90: 940-948. 



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Last Updated on January 19, 2022 by Marie Benz MD FAAD