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MS Trial Alert: Investigators Recruiting for Two Phase 3 Trials Comparing Experimental Tolebrutinib with Aubagio® in Relapsing MS

December 10, 2020

SUMMARY: Investigators are recruiting a total of 1800 people with relapsing forms of MS worldwide for two studies comparing investigational oral tolebrutinib with Aubagio® (teriflunomide, Sanofi Genzyme). The studies – also called GEMINI 1 and GEMINI 2 – are sponsored by Sanofi .
Rationale: Tolebrutinib inhibits an enzyme called “Bruton’s tyrosine kinase,” reducing the activation of B cells, which are immune cells that play a role in the response that affects the brain and spinal cord in MS. Tolebrutinib also penetrates the brain and spinal cord and inhibits  immune cells in the brain called microglia, which have been linked to MS progression. Tolebrutinib is one of several “BTK” inhibitors being tested in the MS pipeline.
Eligibility and Details: Participants should be 18 to 55 years old, and diagnosed with relapsing forms of MS, which include relapsing-remitting disease and active secondary progressive disease (with relapses).
In both studies, all participants will receive active treatment. Half will be randomly assigned to once daily treatment with either tolebrutinib and an inactive placebo matching Aubagio, and the other half will receive Aubagio and an inactive placebo matching tolebrutinib, for 36 months. The primary outcome of both studies will compare how treatment affects the annual rate of relapses. Secondary outcomes include disability worsening, disease activity on MRI scans, quality of life, safety, and laboratory biomarkers of immune and nervous system activity. The study involves up to 16 visits to the study site, and will involve MRI scans, blood draws, clinical exams, and questionnaires.
Please note: This study requires in-person visits to the study site. Precautions are being taken to reduce the on-site risks of exposure to COVID-19.
Contact: To learn more about the enrollment criteria for these studies, and to find out if you are eligible to participate, please call 1-800-633-1610 extension option 6, or email

Online - To see if you might qualify for this clinical trial and to be referred to the local trial center in your area, visit:

In the U.S., sites are enrolling in the following cities:
Arcadia, California
Basalt, Colorado
Baton Rouge, Louisiana
Centerville, Ohio
Columbus, Ohio
Cullman, Alabama
Fort Collins, Colorado
Franklin, Tennessee
Greer, South Carolina
Knoxville, Tennessee
Maitland, Florida
Memphis, Tennessee
Northbrook, Illinois
Oklahoma City, Oklahoma
Patchogue, New York
Raleigh, North Carolina
San Antonio, Texas
Savannah, Georgia
Springfield, Illinois
Sunrise, Florida
Tampa, Florida
Westerville, Ohio
Download a brochure that discusses issues to think about when considering enrolling in an MS clinical trial (PDF).
Without participants in research studies, MS research would come to a standstill. Read more here.
Aubagio is a registered trademark of Sanofi Genzyme.

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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