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Important Changes Have Been Made To Tecfidera’s Prescribing Information

December 9, 2014

Warnings and other important changes have been added to the prescribing information for Tecfidera® (dimethyl fumarate, Biogen Idec). Tecfidera is an oral disease-modifying therapy for adults with relapsing forms of multiple sclerosis.

About the Prescribing Information Changes: The updated information approved by the U.S. Food and Drug Administration includes these additions:
• Provisions were added for temporarily reducing the dose of Tecfidera in those unable to tolerate the maintenance dose.
• A recommendation to reduce the incidence or severity of flushing, as an alternative to the previous recommendation to take Tecfidera with food, is to take uncoated aspirin 30 minutes prior to taking Tecfidera.  A warning has been added about the potential for hypersensitivity reactions, with signs and symptoms including difficulty breathing, swelling of the throat and tongue, and hives.
• In addition to the previous recommendation that individuals have a recent blood count before initiating treatment, it is now recommended that a complete blood count, including lymphocyte count, be obtained after 6 months of treatment, and every 6 to 12 months thereafter, and as clinically indicated. The new information also states that consideration should be given to interrupting treatment if lymphocyte counts are low for more than six months. 
• Information is provided about the unfortunate death of an individual who developed PML (progressive multifocal leukoencephalopathy), a viral infection of the brain that often leads to death or severe disability, after taking Tecfidera for 4 years while enrolled in a clinical trial. Although the individual had experienced prolonged low lymphocyte (white blood cells that fight infection) counts (lymphopenia) for 3.5 years, the role of lymphopenia in the PML has not been established.
o PML may cause a range of symptoms over days to weeks, and may include progressive weakness on one side, clumsiness of limbs, vision disturbances, and changes in thinking, memory and orientation, leading to confusion and personality changes.  

Read more updated information about this medication
Download the updated prescribing information (.pdf)
Download the updated medication guide for patients (.pdf)

Tecfidera is a registered trademark of Biogen Idec

About Multiple Sclerosis

Multiple sclerosis is an unpredictable, often disabling disease of the central nervous system. There is currently no cure for MS. Symptoms vary from person to person and range from numbness and tingling, to mobility challenges, blindness and paralysis. An estimated 1 million people live with MS in the United States. Most people are diagnosed between the ages of 20 and 50, and it affects women three times more than men.

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The National MS Society, founded in 1946, funds cutting-edge research, 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, Twitter, Instagram, YouTube or 1-800-344-4867.


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