Adverse Reactions in 2 Clinical Trials1

The most common adverse reactions (incidence ≥10%, and ≥2% more than placebo) were flushing, abdominal pain, diarrhea, and nausea

Adverse Reactions Reported for TECFIDERA 240 mg BID
at ≥2% Higher Incidence Than Placebo

  TECFIDERAn=769 Placebon=771
Flushing 40% 6%
Abdominal pain 18% 10%
Diarrhea 14% 11%
Nausea 12% 9%
Vomiting 9% 5%
Pruritus 8% 4%
Rash 8% 3%
Albumin urine present 6% 4%
Erythema 5% 1%
Dyspepsia 5% 3%
Aspartate aminotransferase increased 4% 2%
Lymphopenia 2% <1%

Overall discontinuation: discontinuation rates due to an adverse reaction with TECFIDERA were 14% vs 11% with placebo in 2 pivotal trials2


  • Generally began at the start of therapy and usually improved or resolved over time
  • 40% of patients experienced flushing (e.g., warmth, redness, itching, and/or burning sensation) in clinical trials
  • 3% of patients discontinued TECFIDERA for flushing, and <1% had serious flushing symptoms that were not life-threatening but led to hospitalization
  • In the majority of patients, flushing symptoms were mild to moderate in severity
TECFIDERA Incidence of Flushing Events chart
TECFIDERA Incidence of Flushing Events chart

*Flushing consists of the preferred terms of flushing and hot flush. Other related symptoms consist of the preferred terms of erythema, generalized erythema, burning sensation, skin burning sensation, feeling hot, and hyperemia.2

Gastrointestinal (GI) Events1,2

  • Most GI events caused by TECFIDERA were not serious in nature
  • 4% of patients discontinued due to GI events vs placebo (<1%)
  • 1% of TECFIDERA patients experienced serious GI events
  • GI events included nausea, diarrhea, abdominal pain, and/or upper abdominal pain
TECFIDERA Incidence of GI Events chart
TECFIDERA Incidence of GI Events chart

References: 1. TECFIDERA Prescribing Information, Biogen, Cambridge, MA. 2. Data on file, Biogen.