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Risks and Side Effects

Straight talk about side effects.

As with any medication, it’s important to talk to your doctor about the possibility of side effects with EXONDYS 51. Here’s what you should know about side effects experienced by those receiving EXONDYS 51 in clinical studies.

Allergic reactions can happen.

Allergic reactions have been noted in patients treated with EXONDYS 51, including:

  • Rash
  • Hives
  • Fever
  • Flushing
  • Cough
  • Difficulty breathing
  • Wheezing
  • Low blood pressure
  • Rash
  • Hives
  • Fever
  • Flushing
  • Cough
  • Difficulty breathing
  • Wheezing
  • Low blood pressure

Seek immediate medical care if signs and symptoms of allergic reactions happen.

Our clinical trial participants

In the EXONDYS 51 clinical development program, we assessed the drug’s safety and tolerability based on 107 Duchenne patients who received at least one intravenous dose of EXONDYS 51. Most of these patients received the recommended dose of 30 mg/kg weekly. All of the patients were male, between the ages of 4 and 19, and most (89%) were Caucasian.  Each had genetic test results confirming his amenability to exon-skipping therapy.

Common side effects.

The side effects that occurred at least 25% more often in 8 patients treated with EXONDYS 51 by intravenous infusion than in 4 patients who received a placebo were:

Side effects include problems with balance, vomiting, and skin irritation
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The most common side effects were problems with balance and vomiting.

Additional side effects with EXONDYS 51.

In patients who received EXONDYS 51 for up to 4 years in clinical studies, the following side effects were reported in at least 10% of patients and occurred more often than at the same dose of EXONDYS 51:

  • Vomiting
  • Bruising
  • Scratches
  • Joint paint
  • Rash
  • IV site pain
  • Infections of the upper airways
  • Vomiting
  • Bruising
  • Scratches
  • Joint paint
  • Rash
  • IV site pain
  • Infections of the upper airways

Seek immediate medical care if signs and symptoms of allergic reactions happen.

EXONDYS 51 patient Micah, age 8, smiling and stepping forward with hands on hips

A phone call away

As with any medication, please talk to your doctor if you experience any side effects from EXONDYS 51. We encourage you to report negative side effects of all prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088. You may also report side effects to Sarepta Therapeutics at 1-888-SAREPTA (1-888-727-3782).

 

Please see the full Prescribing Information for EXONDYS 51 (eteplirsen).

Related FAQs

Is the treatment effective?

Weekly infusions of EXONDYS 51 helped the body make a shorter form of the dystrophin protein in some boys. View the results from clinical studies.

 

EXONDYS 51 is used to treat Duchenne in patients who have a confirmed mutation in the dystrophin gene that can be treated by skipping exon 51. EXONDYS 51 was approved under accelerated approval. Accelerated approval allows for drugs to be approved based on a marker that is considered reasonably likely to predict a clinical benefit that has not been proven. EXONDYS 51 treatment increased the marker, dystrophin, in skeletal muscle in some patients. Verification of a clinical benefit may be needed for EXONDYS 51 to continue to be approved.

See All FAQs

WHAT IS EXONDYS 51® (eteplirsen)?

EXONDYS 51 is used to treat Duchenne muscular dystrophy (DMD) in patients who have a confirmed mutation in the dystrophin gene that can be treated by skipping exon 51.

EXONDYS 51 was approved under accelerated approval. Accelerated approval allows for drugs to be approved based on a marker that is considered reasonably likely to predict a clinical benefit that has not been proven. EXONDYS 51 treatment increased the marker, dystrophin, in skeletal muscle in some patients. Verification of a clinical benefit may be needed for EXONDYS 51 to continue to be approved.

IMPORTANT RISK INFORMATION

Allergic reactions, including rash, hives, fever, flushing, cough, difficulty breathing, wheezing, and low blood pressure have occurred in patients who were treated with EXONDYS 51. Seek immediate medical care if signs and symptoms of allergic reactions occur.

Side effects that happened at least 25% more often in 8 patients treated with EXONDYS 51 by intravenous infusion than in 4 patients treated with an inactive intravenous infusion were problems with balance (38%, 0%), vomiting (38%, 0%), and skin irritation (25%, 0%). The most common side effects were problems with balance and vomiting.

In patients who received EXONDYS 51 for up to 4 years in clinical studies, the following side effects were reported in at least 10% of patients and occurred more often than at the same dose of EXONDYS 51: vomiting, bruising, scratches, joint pain, rash, IV site pain, and infections of the upper airways.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088. You may also report side effects to Sarepta Therapeutics at 1-888-SAREPTA (1-888-727-3782).

READ MORE

WHAT IS EXONDYS 51® (eteplirsen)?

EXONDYS 51 is used to treat Duchenne muscular dystrophy (DMD) in patients who have a confirmed mutation in the dystrophin gene that can be treated by skipping exon 51.

EXONDYS 51 was approved under accelerated approval. Accelerated approval allows for drugs to be approved based on a marker that is considered reasonably likely to predict a clinical benefit that has not been proven. EXONDYS 51 treatment increased the marker, dystrophin, in skeletal muscle in some patients. Verification of a clinical benefit may be needed for EXONDYS 51 to continue to be approved.

IMPORTANT RISK INFORMATION

Allergic reactions, including rash, hives, fever, flushing, cough, difficulty breathing, wheezing, and low blood pressure have occurred in patients who were treated with EXONDYS 51. Seek immediate medical care if signs and symptoms of allergic reactions occur.

Side effects that happened at least 25% more often in 8 patients treated with EXONDYS 51 by intravenous infusion than in 4 patients treated with an inactive intravenous infusion were problems with balance (38%, 0%), vomiting (38%, 0%), and skin irritation (25%, 0%). The most common side effects were problems with balance and vomiting.

In patients who received EXONDYS 51 for up to 4 years in clinical studies, the following side effects were reported in at least 10% of patients and occurred more often than at the same dose of EXONDYS 51: vomiting, bruising, scratches, joint pain, rash, IV site pain, and infections of the upper airways.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088. You may also report side effects to Sarepta Therapeutics at 1-888-SAREPTA (1-888-727-3782).

Please see the full Prescribing Information for EXONDYS 51 (eteplirsen).