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Know Your Mutation

Identifying your child’s mutation.

EXONDYS 51 is used to treat Duchenne muscular dystrophy 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.

About 13% of people diagnosed with Duchenne have a mutation amenable to exon 51 skipping

 

What does amenable mean?

Amenability describes a potential responsiveness to treatment. If your child’s genetic mutation is a deletion of one or more exons in the dystrophin gene that are amenable to exon 51 skipping, then it may be responsive—or, amenable—to EXONDYS 51

If your child has been diagnosed with Duchenne, ask your doctor about genetic testing.

The goal of a genetic test is to identify the genetic mutation so treatment options can be considered. To learn if your child’s mutation is amenable to treatment with EXONDYS 51, take the immediate step of asking your doctor to order a genetic test.

 

Already know the mutation?

Understanding your child's mutation and amenability.

Your doctor or genetic counselor will be able to interpret the genetic test results to identify the genetic mutation and determine amenability to treat with EXONDYS 51.

EXONDYS 51 patient Graysen, age 2, lying on floor on his back looking at camera and smiling

EXONDYS 51 patient Graysen, age 2, lying on floor on his back looking at camera and smiling

Reexamine or retest.

If you’ve had a genetic test, it’s important to know that testing methods have changed over time and may now provide more accurate or additional information. Ask your doctor to review older test results or request a new test so they can determine if your child’s deletion is amenable to exon 51 skipping.

 

Ask your doctor if a genetic mutation was identified in your child’s genetic test.

What can I learn from a genetic test?

A genetic test will:

  • Confirm a diagnosis of Duchenne so you can take action on your child’s behalf
  • Identify the genetic mutation so treatment options can be considered
  • Assist with family planning

See Sample Test Results

We know the mutation. Is my child amenable?

EXONDYS 51 is intended for patients with Duchenne who have genetic mutations that are large deletions—where one or more specific exons, listed below, are missing. A doctor or genetic counselor will need to interpret your child's genetic test results to determine if your child can take EXONDYS 51. If the genetic mutation is not amenable to treatment with EXONDYS 51, talk to your doctor about other potential treatments.

 

The deletions, or ranges of deletions, that are theoretically amenable to exon 51 skipping are shown here.

Choose an exon range.

Find out how EXONDYS 51 may help the body make a shorter form of the dystrophin protein.

This educational table is not intended to make a diagnosis or replace discussion with your doctor or genetic counselor.

EXONDYS 51 patient Xavier, age 10, standing and looking at camera with his hands folded EXONDYS 51 patient Xavier, age 10, standing and looking at camera with his hands folded

If your child has been diagnosed with Duchenne, talk to your doctor to see if EXONDYS 51 is right for your child.

“Families receive this diagnosis and sometimes they don’t know what’s next. SareptAssist Case Managers are here to help families navigate the process of starting treatment with EXONDYS 51.”

–Ashley, SareptAssist Case Manager

SareptAssist Case Manager Ashley with EXONDYS 51 patient Zyler, age 5, cheek to cheek and smiling at the camera
Meet Ashley, SareptAssist Case Manager
Meet Ashley, SareptAssist Case Manager

 

Related FAQs

What is a genetic mutation?

A mutation is a change in a person's DNA. Mutations range in size from a small (a single rung on a ladder) to a large segment of DNA. Every mutation causes a different effect on our bodies. Learn more about the role of genetics in Duchenne.

What is a deletion?

A deletion is a type of mutation where genetic material is missing. Duchenne is caused by a mutation on the dystrophin gene; the mutation may be a deletion, duplication, or other change in the gene.  Learn about genetic testing for Duchenne.

My child has a deletion and is missing exon 51. Can they take EXONDYS 51?

Please discuss your child's genetic test results and treatment options with your child's doctor. For EXONDYS 51 to work, exon 51 must be present in the dystrophin gene. Your child's doctor or a genetic counselor is the best person to help you understand genetic testing. Explore what genetic test results can tell you.

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).