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Phase 3 Clinical Trials of Evobrutinib Did Not Meet Primary Endpoint, Announces Company

December 15, 2023

Merck KGaA, announced in a press release on December 5 that its two Phase 3 clinical trials, testing the safety and effectiveness of oral evobrutinib in people with relapsing MS, did not meet their primary endpoints of reducing annualized relapse rates compared to oral teriflunomide (Aubagio®, Sanofi Genzyme).
  • More Details: In each of these studies (called evolutionRMS1 and evolutionRMS2), participants with relapsing MS were randomly assigned to receive evobrutinib or Aubagio for up to 156 weeks.
  • Evobrutinib inhibits an enzyme called “Bruton’s tyrosine kinase,” reducing the activation of B cells and other immune cells that play a role in the response that affects the brain and spinal cord in MS. “BTK” inhibitors are small molecules that can more easily cross into the brain to exert effects on the nervous system. Evobrutinib is one of several BTK inhibitors being tested in clinical trials involving people with relapsing or progressive MS.
  • The company noted that both those taking evobrutinib and those taking Aubagio experienced low relapse rates during the trial. The results are still being analyzed and will be presented and published at a later date.
  • “It is disappointing that these early results do not show increased benefit of this experimental treatment for MS,” says Bruce Bebo, PhD, Executive Vice President of Research for the National MS Society. “We look forward to seeing the complete data from the study.”
Read more about medications for MS.
Aubagio is a registered trademark of Sanofi Genzyme

About Multiple Sclerosis

Multiple sclerosis is an unpredictable disease of the central nervous system. Currently there is no cure. Symptoms vary from person to person and may include disabling fatigue, mobility challenges, cognitive changes, and vision issues. An estimated 1 million people live with MS in the United States. Early diagnosis and treatment are critical to minimize disability. Significant progress is being made to achieve a world free of MS.

About the National Multiple Sclerosis Society

The National MS Society, founded in 1946, is the global leader of a growing movement dedicated to creating a world free of MS. The Society funds cutting-edge research for a cure, drives change through advocacy and provides programs and services to help people affected by MS live their best lives. Connect to learn more and get involved:, Facebook, X, formerly known as Twitter, Instagram, YouTube or 1-800-344-4867.


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