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Atidarsagene Autotemcel Injection

Why is this medication prescribed?

Atidarsagene autotemcel injection is used to treat children with pre-symptomatic or early metachromatic leukodystrophy (MLD; an inherited condition in which certain fats [lipids] build up in the brain, spinal cord, and nerves, resulting in nerve and brain damage). Atidarsagene autotemcel injection is in a class of medications called autologous cellular immunotherapy, a type of medication prepared using cells from the patient's own blood. It works by helping your body to break down the fats and stop or slow the progression of nerve and brain damage.

How should this medicine be used?

Atidarsagene autotemcel injection comes as a suspension (liquid) to be injected intravenously (into a vein) by a doctor or nurse in a hospital. Atidarsagene autotemcel injection is given as a one-time dose, which is contained in 1 to 8 infusion bags. Each infusion bag is usually given over no more than 30 minutes. Before you receive your atidarsagene autotemcel dose, your doctor or nurse will administer other chemotherapy medications to prepare your body for atidarsagene autotemcel.

Before your dose of atidarsagene autotemcel injection is to be given, a sample of your blood stem cells will be taken at a hospital or treatment center using a process called mobilization and apheresis (a process that removes blood stem cells from the body). The sample will be sent to the manufacturer to prepare a dose of atidarsagene autotemcel injection. Because this medication is made from your own cells, it must be given only to you.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before receiving atidarsagene autotemcel injection,

  • tell your doctor and pharmacist if you are allergic to atidarsagene autotemcel, any other medications, dimethyl sulfoxide (DMSO), or any of the ingredients in atidarsagene autotemcel injection. Ask your pharmacist for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if your child has or has ever had hepatitis B or C (a virus that infects the liver and may cause severe liver damage), cytomegalovirus (CMV), human immunodeficiency virus (HIV), blood clots, or kidney or liver disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you are a female of childbearing age, you will need to have a pregnancy test before you start treatment with atidarsagene autotemcel injection. If you are a male or female of childbearing age, you should use birth control to prevent pregnancy during you treatment during you treatment and for 6 months after you receive atidarsagene autotemcel injection. If you become pregnant while receiving atidarsagene autoleucel, call your doctor immediately.
  • do not donate blood, organs, tissues, or cells for transplantation after you receive atidarsagene autotemcel injection.
  • check with your doctor to see if you need to receive any vaccinations. Do not have any vaccinations without talking to your doctor for at least 6 weeks before starting chemotherapy, during your atidarsagene autotemcel treatment, and until your doctor tells you that your immune system has recovered.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What side effects can this medication cause?

Atidarsagene autotemcel injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • mouth sores

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

  • rash; itching; hives; swelling of your face, mouth, tongue, or throat; chest pain; fast heartbeat; or difficulty swallowing or breathing
  • fever, sore throat, swollen glands, ongoing cough and congestion, or other signs of infection
  • weakness, decreased muscle tone, cognitive deterioration, behavioral problems, vomiting, and swallowing difficulties
  • pain, discoloration, or swelling of an arm, legs or feet, with warmth over the affected area
  • shortness of breath
  • difficulty breathing
  • chest pain
  • numbness or weakness on one side of the body
  • unusual bruising or bleeding; nose bleed; severe headache; blood in urine, stool, or vomit; coughing up blood; or unusual abdominal or back pain

Atidarsagene autotemcel injection may increase the risk that you will develop blood cancers. Your blood will be monitored at least yearly for at least 15 years after your treatment with atidarsagene autotemcel injection. Talk to your doctor about the risks of taking this medication.

Atidarsagene autotemcel injection may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to atidarsagene autotemcel injection.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are receiving atidarsagene autotemcel injection. You should know that you may have a false-positive test for HIV after you receive atidarsagene autotemcel injection.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Lenmeldy®
Last Revised - 05/20/2024