Hemgenix: Uses, Side Effects and Dosage

What HEMGENIX is used for:

People with Hemophilia B are born with a defect in a gene and they do not make enough of a protein known as Factor IX. This protein is important for blood to clot and stop any bleeding. People with Hemophilia B will become sick due to bleeding without treatment. HEMGENIX is given to help make enough working Factor IX protein to stop bleeding in patients with Hemophilia B.

How HEMGENIX works:

The active substance in HEMGENIX is based on a virus that does not cause disease in humans. This virus cannot spread in the body but can deliver a copy of the Factor IX gene into cells of the body. This allows the body to produce the Factor IX protein and raise the levels of working Factor IX in the blood. This treatment is known as a gene therapy and the Factor IX protein made will help the blood to clot more normally and prevent or reduce bleeding episodes in patients with Hemophilia B.

The ingredients in HEMGENIX are:

Medicinal ingredient(s): Etranacogene dezaparvovec.

Non-medicinal ingredients: Disodium phosphate, Hydrochloric acid (for pH adjustment), Polysorbate-20, Potassium chloride, Potassium dihydrogen phosphate, Sodium chloride, Sucrose, Water for injection

This medicine contains recombinant adeno-associated viral vectors.

HEMGENIX comes in the following dosage form(s):

Each HEMGENIX vial contains 1 x 10¹³ gene copies (gc)/mL of etranacogene dezaparvovec.

HEMGENIX is a suspension for intravenous infusion.

HEMGENIX is a clear, colourless solution. After dilution, HEMGENIX is a clear, colourless solution.

Do not use this medicine if you notice particles, cloudiness or discoloration.

Do not use HEMGENIX if:

You are allergic to etranacogene dezaparvovec or to any of the other ingredients of this medicine.

If the above applies to you, or if you are unsure of the above, please talk to your healthcare professional before you receive HEMGENIX.

To help avoid side effects and ensure proper use, talk to your healthcare professional before you receive HEMGENIX. Talk about any health conditions or problems you may have, including if you:

• Have an infection
• Have or had liver or kidney problems
• Are planning on having children

For your personal safety, the treatment with HEMGENIX will take place under the supervision of your healthcare professional in a clinical setting.

Before treatment with HEMGENIX

Your healthcare professional will perform several tests before you are given HEMGENIX treatment.

• Antibody blood tests: Your healthcare professional will conduct blood tests to check for certain antibodies (proteins) before treatment with HEMGENIX, including:

  • Blood tests to check for the amount of antibodies in your blood directed against the type of virus used to make HEMGENIX. If you have too many of these antibodies you will not receive HEMGENIX.
  • Blood tests to check for the presence of antibodies in your blood directed against the human Factor IX protein (Factor IX inhibitors). If you test positive for these antibodies, another test will be performed in approximately 2 weeks. If both the initial test and re-test results are positive, you will not receive HEMGENIX.

• Liver health: If you have poor liver health you may not receive HEMGENIX. Your healthcare professional will check the status of your liver health before you start treatment with HEMGENIX and perform:

  • Blood tests to check the level of liver enzymes in your blood
  • Liver ultrasound
  • Tests to check for scarring or thickening of your liver (elastography testing).

During or shortly after HEMGENIX infusion

Your healthcare professional will monitor you during or shortly after HEMGENIX infusion.

• Infusion-related reactions: Infusion-related side effects can occur during or shortly after you are given the HEMGENIX infusion (drip). Your healthcare professional will monitor you during HEMGENIX infusion and for at least 3 hours after you are given HEMGENIX.

  • Symptoms of such side effects are listed in section “Possible side effects from using HEMGENIX”. Tell your healthcare professional or nurse immediately if you experience these or any other symptoms during or shortly after the infusion.
  • Depending on your symptoms, your infusion may be slowed down or interrupted. If the infusion is interrupted, it can be restarted at a slower rate when the infusion reaction is resolved. Your healthcare professional may also consider if you should be given another medicine (corticosteroids) to help manage the infusion reaction.

After treatment with HEMGENIX

After treatment with HEMGENIX, your healthcare professional will continue to check your health. It is important that you discuss the schedule for these blood tests with your healthcare professional so that they can be carried out as necessary.

• Liver enzymes: HEMGENIX will trigger a response within your immune system that could lead to an increased level of certain liver enzymes in your blood called transaminases (transaminitis). Your healthcare professional will regularly monitor your liver enzyme levels to ensure that the medicine is working as it should:

  • In the first 3 months you will have blood tests once per week to monitor your liver enzyme levels.

    • If you experience an increase in liver enzymes, you may have more frequent blood tests to check the levels of your liver enzymes, until they return to normal. You may also need to take another medicine (corticosteroids) to manage these side effects.
    • Your healthcare professional may also perform additional tests to exclude other causes for the increase in your liver enzymes, if needed, in consultation with a healthcare professional experienced in liver diseases (hepatologist).
  • Your healthcare professional will repeat liver enzyme testing every three months from month 4 up to one year after you are given HEMGENIX to continue checking of your liver health. In the second year after you are given HEMGENIX, your healthcare professional will follow up your liver enzymes half-yearly. After the second year, your healthcare professional will check your liver enzymes annually for at least 5 years after you are given HEMGENIX.

• Factor IX levels: Your healthcare professional will regularly check your Factor IX levels to see if treatment with HEMGENIX was successful.

  • In at least the first 3 months after you are given HEMGENIX, you will have blood tests once per week to check your Factor IX levels.

Discontinuation of other Hemophilia B treatments

After HEMGENIX use, talk to your healthcare professional about if or when you should stop your other Hemophilia B treatments and develop a treatment plan of what to do in case of surgery, trauma, bleeds, or any procedures that will increase your risk of bleeding. It is important to continue your monitoring and keep your healthcare professional visits. Discuss if you need to take other medicines to manage your Hemophilia B or any side effects of treatment you may have.

Risk of liver cancer (hepatocellular carcinogenicity)

• HEMGENIX will insert into cells in your body and it could possibly insert into your DNA. This could contribute to a risk of cancer, such as liver cancer. Although this has yet to be reported, this remains possible because of the nature of the medicine. You should therefore discuss this with your physician.

• If you are a patient with risk factors for liver cancer (you have liver cirrhosis or scarring and thickening of the liver, or Hepatitis B, Hepatitis C, or fatty liver), your healthcare professional will monitor you liver health yearly for at least 5 years after HEMGENIX administration and perform the following tests:

  • Annual liver ultrasound and
  • Annual blood tests to check for increases in protein (alpha-fetoprotein).

Avoiding blood donations and donations for transplantations

To ensure HEMGENIX DNA is not transferred from you to another person, you will not be able to donate blood, organs, tissues, or cells after you have been treated with HEMGENIX.

Other warnings you should know about:

• Children and adolescents: HEMGENIX is not recommended for children or adolescents under the age of 18.

• Pregnancy, breastfeeding, and fertility: HEMGENIX is not intended for use in women and there are no data regarding HEMGENIX in pregnant or breast-feeding women.

• Driving and using machines: Some side effects of HEMGENIX may affect your ability to drive or use machines. You should wait until the side effects go away before you drive or use machines.

• Shedding and Contraception:
• The active substance in HEMGENIX may be excreted through your blood, semen, and other bodily waste, a process called shedding.
• It is recommended that you and your female partner use appropriate barrier contraception for 2 years from treatment to prevent HEMGENIX DNA to be transferred to offspring.

Tell your healthcare professional about all the medicines you take, including any drugs, vitamins, minerals, natural supplements or alternative medicines.

• Interactions between HEMGENIX and other drugs, vitamins, minerals, natural supplements or alternative medicines have not been established.

How to take HEMGENIX:

• HEMGENIX will be given to you in a hospital setting under direction of a healthcare professional experienced and trained in the treatment of Hemophilia.
• HEMGENIX will be given to you only once by a single slow infusion (drip) into a vein after dilution with 0.9% sodium chloride solution (normal saline).
• There will be no dose adjustments allowed for medical conditions.
• If you have any questions on the use of HEMGENIX ask your healthcare professional.

Usual dose:

Your healthcare professional will work out the correct dose for you, based on your body weight.

The dose is 2 x 10¹³ genome copies, the unit the HEMGENIX dose is measured, per kg of your body weight.

Overdose:

There are no clinical study data regarding overdose with HEMGENIX.

Missed dose:

HEMGENIX is administered only once.

Possible side effects from using HEMGENIX:

Like all medicines, this medicine can cause side effects, although not everybody gets them.

These are not all the possible side effects you may have when taking HEMGENIX. If you experience any side effects not listed here, tell your healthcare professional.

The following side effects were observed in clinical studies with HEMGENIX:

Very Common (may occur with more than 1 in 10 patients)

• Tiredness (Fatigue)
• Headache
• Flu-like illness (Influenza-like illness)
• Increased levels of liver enzymes in the blood (Alanine aminotransferase and Aspartate aminotransferase)
• Increased blood levels of creatine phosphokinase, an enzyme (protein) found mainly in the heart, brain and skeletal muscle

Common (may occur with up to 1 in 100 patients)

• Dizziness
• Feeling sick (Nausea)
• Feeling generally unwell (Malaise)
• Increased blood levels of bilirubin (a yellow breakdown substance of red blood cells that is not being removed well by the liver)

Serious side effects and what to do about them

If you have a troublesome symptom or side effect that is not listed here or becomes bad enough to interfere with your daily activities, tell your healthcare professional.

Reporting side effects

We recommend that CSL Behring Canada be copied when reporting suspected side effects, at the following address:

AdverseReporting@CSLBehring.com

Storage:

As this medicine will be given in a clinical setting, the clinical personal is responsible for the correct storage of the medicine before and during its use, as well as for its correct disposal. The following information is intended for health professionals only.

• Keep out of reach and sight of children.
• Store in a refrigerator (2 to 8°C). Do not freeze.
• Store vials in the original package in order to protect from light.
• Once diluted with sodium chloride 9 mg/mL (0.9%) solution for injection, HEMGENIX can be stored at 15 °C - 25 °C in the infusion bag protected from light for up to 24 hours after the dose preparation.
• Do not use this medicine after the expiry date which is stated on the vial label and carton after EXP.

Contents of the package

HEMGENIX is supplied in vials containing 10 mL of etranacogene dezaparvovec.

The total number of vials in a pack corresponds to the dosing requirement for individual patient depending on his body weight and is provided on the package.

If you want more information about HEMGENIX:

• Talk to your healthcare professional
• Find the full product monograph that is prepared for healthcare professionals and includes the Patient Medication Information by visiting the Health Canada Drug Product Database website (https://www.canada.ca/en/health-canada/services/drugs-health-products/drug-products/drug-product-database.html); the manufacturer’s website https://www.cslbehring.ca/ or by calling 1-866-773-7721.

Date of Authorization: 2025-05-16