FDA: Rare, But Serious Risk of Stroke with MS Drug Alemtuzumab

The FDA advises health care providers to counsel patients receiving alemtuzumab on symptoms related to stroke and arterial dissection.

FDA officials are warning about rare but serious risks of stroke and blood vessel wall tears with multiple sclerosis (MS) drug alemtuzumab (Lemtrada), according to a safety announcement.

According to the statement, cases of stroke and tears in the lining of arteries in the head and neck have occurred in patients with MS shortly after they received alemtuzumab. The FDA has added a new warning about these risks to the prescribing information in the drug label and to the patient Medication Guide, as well as to the existing Boxed Warning.

Cases are rare, with the FDA identifying 13 worldwide reported cases of ischemic and hemorrhagic stroke or arterial dissection that occurred shortly after the patient received alemtuzumab. However, these problems can lead to permanent disability and even death.

Individuals who developed stroke or tears in the artery linings as a result of taking alemtuzumab experienced symptoms within 1 day of receiving the medication and 1 patient reported symptoms that occurred 3 days after treatment.

The FDA advises patients or caregivers to seek emergency treatment if the patient experiences any of the following signs or symptoms:

  • Sudden numbness or weakness in the face, arms, or legs, especially if it occurs on only 1 side of the body.
  • Sudden confusion, trouble speaking, or difficulty understanding speech.
  • Sudden trouble seeing in 1 or both eyes.
  • Sudden trouble with walking, dizziness, or loss of balance or coordination.
  • Sudden severe headache or neck pain.

Health care professionals should advise patients at every alemtuzumab infusion to seek emergency medical attention if they experience these symptoms. The agency noted that diagnosis can be complicated because early symptoms are not specific, but providers should evaluate patients who complain of symptoms consistent with these conditions.

Alemtuzumab is also approved under the brand name Campath for the treatment of B-cell chronic lymphocytic leukemia. The Campath drug label will also be updated to include these risks.


FDA warns about rare but serious risks of stroke and blood vessel wall tears with multiple sclerosis drug Lemtrada (alemtuzumab) [news release]. FDA’s website. https://bit.ly/2AxcozZ. Accessed November 29, 2018.