Common MS Drug Causes Rare but Potentially Deadly Allergic Reactions, FDA Warns

Copaxone and its generic form, Glatopa, may lead to anaphylaxis even in patients who’ve been taking the medication for months without incident.
Common MS Drug Causes Rare but Potentially Deadly Allergic Reactions, FDA Warns
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The U.S. Food and Drug Administration (FDA) has added a so-called “black box” (“boxed warning”) alert to the multiple sclerosis drug Copaxone (glatiramer acetate) and its generic version, Glatopa, because of rare but potentially fatal allergic reactions.

Worldwide, a total of 82 patients taking Copaxone experienced severe allergic reactions known as anaphylaxis, which required emergency room visits or hospitalizations, and 6 people died since the drug was approved, the FDA said in statement.

“Anaphylaxis associated with glatiramer acetate is a very rare but potentially life-threatening adverse effect, and anaphylaxis can occur at any time after initiating therapy,” says Jeffrey Cohen, MD, a neurologist at the Mellen Center for Multiple Sclerosis at the Cleveland Clinic.

Copaxone was first approved by the FDA as a multiple sclerosis treatment in 1996, and an estimated 32,000 patients a year take this medicine in the United States alone, the FDA noted. Anaphylaxis cases appear to be extremely low compared with how often the medicine is used, the FDA said.

How Do You Know if You’re Having a Severe Allergic Reaction?

If someone with multiple sclerosis experiences any symptoms of anaphylaxis after taking glatiramer acetate, they should seek immediate medical attention by going to an emergency room or calling 911, the FDA said. These symptoms include:

  • Wheezing or difficulty breathing
  • Swelling of the face, lips, or throat
  • Hives
  • Severe rash

Most of the patients who experienced anaphylaxis associated with Coxapone or Glatopa had severe allergic reactions within one hour after injecting the medicine, according to the FDA.

The FDA emphasizes that early symptoms of anaphylaxis can resemble some of the side effects that people more commonly experience right after or within minutes of taking Copaxone or Glatopa. These include:

  • Flushing or warmth
  • Chest pain
  • Fast heartbeat
  • Anxiety
  • Breathing problems or tightness in the throat
  • Swelling, rash, hives, or itching

Side effects of glatiramer acetate typically go away on their own within 15 to 30 minutes, the FDA said.

Anytime patients have post-injection side effects that don’t clear up quickly, or get worse, they should call 911, just as they would for symptoms of anaphylactic shock.

Severe Allergic Reactions Can Occur at Any Point During Treatment

Rare, severe allergic reactions to Copaxone or Glatopa may occur at any point during treatment, even after patients have received many doses of the medicine without any troubling symptoms, the FDA said.

A total of 19 patients had been taking the medicine for more than a year before they had a severe allergic reaction. One patient went into anaphylactic shock and died after their first dose, however.

Patients who experience anaphylaxis should never take the medicine again, the FDA said. When they experience milder side effects, they should halt treatment and only resume it after consulting with their doctor.

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Lisa Rapaport

Author
Lisa Rapaport is a journalist with more than 20 years of experience on the health beat as a writer and editor. She holds a master’s degree from the UC Berkeley Graduate School of Journalism and spent a year as a Knight-Wallace journalism fellow at the University of Michigan. Her work has appeared in dozens of local and national media outlets, including Reuters, Bloomberg, WNYC, The Washington Post, Los Angeles Times, Scientific American, San Jose Mercury News, Oakland Tribune, Huffington Post, Yahoo! News, The Sacramento Bee, and The Buffalo News.
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Resources
  1. FDA Adds Boxed Warning About a Rare but Serious Allergic Reaction Called Anaphylaxis with the Multiple Sclerosis Medicine Glatiramer Acetate (Copaxone, Glatopa). U.S. Food and Drug Administration. January 22, 2025.