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Oral Malaria Drug Shows Benefit in Small Study of People with Primary Progressive MS

October 4, 2021

Using a unique study design, researchers found evidence that generic oral hydroxychloroquine reduced disability progression in a small cohort of people with primary progressive MS. Further study in larger, controlled trials is needed to determine whether hydroxychloroquine can safely be used to slow progression in people with primary progressive MS.
  • Primary progressive MS (PP MS) is characterized by worsening neurologic function (accumulation of disability) from the onset of symptoms, without early relapses or remissions. One medication -- Ocrevus® (ocrelizumab) – has been approved by the U.S. Food and Drug Administration for the treatment of PP MS. There is a need for more therapy options for progressive MS, and also for innovative clinical trial designs that can more quickly test therapies for their potential to protect the nervous system from harm and slow or stop progression.
  • This team tested a generic oral medication called hydroxychloroquine, which has been used to treat malaria, arthritis and lupus. It reduces activation of brain cells called microglia. Evidence indicates that microglia play a role in the worsening of disability in MS.
  • To determine whether hydroxychloroquine has potential to be tested in large, controlled trials in people with PP MS, these researchers used a novel study design. Instead of a traditional study that would compare those treated against those on inactive placebo, the team determined an expected rate of disability progression (occurring in 40% of participants) based on data obtained in large clinical studies of people with PP MS. Then they tested whether treatment with hydroxychloroquine could improve upon that rate in 35 people with PP MS.
  • The study met its goal, as disability progressed in 23% of participants, compared to the 40% expected. Serious adverse events occurred in 12% of participants, but were unlikely related to treatment with hydroxychloroquine. Nearly one-third of participants experienced other side effect related to hydroxychloroquine (vivid dreams, nausea, stomach upset, and tinnitus).
  • The authors note that based on these results, further study is warranted in larger, controlled trials, to confirm whether hydroxychloroquine can slow disability in people with PP MS.
  • This trial was supported through a grant from the MS Translational Clinical Trials Program of the Hotchkiss Brain Institute at the University of Calgary.
Read more about primary progressive MS
Read about the International Progressive MS Alliance accelerating development of effective treatments for progressive MS
“Hydroxychloroquine for Primary Progressive Multiple Sclerosis” by Marcus W. Koch MD PhD, Luanne M. Metz MD, and colleagues (University of Calgary, Canada and other institutions) is published in Annals of Neurology (First published: 30 September 2021).

About Multiple Sclerosis

Multiple sclerosis is an unpredictable, often disabling disease of the central nervous system. Symptoms range from numbness and tingling to blindness and paralysis, and there is currently no cure for MS. The progress, severity and specific symptoms of MS in any one person cannot yet be predicted, but advances in research and treatment are leading to better understanding and moving us closer to a world free of MS. An estimated 1 million people live with MS in the United States. Most people with MS are diagnosed between the ages of 20 and 50, and it affects women three times more than men.


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