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Experimental Therapy Targeting Cells Infected with Epstein-Barr Virus Fails to Show Benefit, Says Company

November 13, 2023

Atara Biotherapeutics, Inc. announced that its experimental therapy called ATA188 failed to reverse disability for people with progressive MS after a 12-month phase 2 clinical trial. The treatment also showed no benefits on MRIs or other tests. The company had anticipated that targeting and eliminating immune cells infected with the Epstein-Barr virus (EBV) would change the course of progressive MS and reduce disability.

According to a press release, the company continues to review the trial data to understand why the phase 2 results did not match the benefits seen in the phase 1 trials. They will also analyze why a higher percentage (16%) of people on inactive placebo showed improvements compared to those on the active therapy (6%). Further details of the trial have not yet been released.

More research is ongoing worldwide to understand the role of EBV as a trigger for MS and possibly as a catalyst for ongoing disease activity.

Read more about EBV and MS

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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