The Food and Drug Administration (FDA) is warning Lemtrada (alemtuzumab) consumers about rare but very serious cases of stroke and blood vessel wall tears in the lining of arteries in the head and neck, called arterial dissection, that lead to permanent disability or death. The drug is used to treat people with multiple sclerosis (MS). Recent patients have experienced these side effects shortly after receiving the drug.  

The warning about these risks has been added to prescribing information on the drug label and to the patient medication guide. The drug alemtuzumab is also branded as Campath, a drug used to treat B-cell chronic lymphocytic leukemia (B-CLL). The information on Campath labels and guides have been updated as well.

In the recent FDA warning, patients are prompted to seek emergency treatment if they experience:

  • Sudden numbness or weakness in the face, arms, or legs, especially if it occurs on only one side of the body
  • Sudden confusion, trouble speaking, or difficulty understanding speech
  • Sudden trouble seeing in one or both eyes
  • Sudden trouble with walking, dizziness, or loss of balance or coordination
  • Sudden severe headache or neck pain

Lemtrada is a prescription infusion medicine used to treat adults with relapsing forms of MS. It’s generally used by people who have tried other methods and medicines that have not worked. It’s unknown whether the drug is safe for persons under 17 years old due to its high risks of infusion reactions, autoimmunity and some cancers. Lemtrada is administered in eight doses over the course of two years and each dose is followed up with intense monitoring by health professionals.

Since Lemtrada was approved by the FDA in 2014 to treat MS, 13 cases of stroke or arterial dissection have been reported, 12 of them being reported within one of the patient receiving the dose. Risk of stroke was added to the boxed warning, the FDA’s prominent warning.