Potential Associated Risks

ARE THERE POTENTIAL RISKS ASSOCIATED WITH HEMGENIX®?

HEMGENIX® may cause side effects, both in the short term and long term.

HEMGENIX® was generally well tolerated (up to 3 years) in clinical trials with no treatment-related serious adverse events and no development of FIX inhibitors reported.1 There was at least 1 treatment-related side effect experienced by all participants in the study, with most of them being mild (76%).1

SHORT-TERM SIDE EFFECTS

You may experience side effects during or immediately after the gene therapy infusion. The most common side effects seen in clinical trials were:2,3

  • Headaches
  • Flu-like symptoms
  • Allergic reactions
  • Dizziness
  • Eye itching
  • Stomach discomfort
  • Chest discomfort
  • Rash
  • Fever
  • Feeling sick
  • Feeling tired
  • Feeling unwell

Your doctor or nurse will check for side effects during and after the infusion.

POTENTIAL MEDIUM- AND LONG-TERM RISKS3

There are also some potential risks in the first few weeks, months, and years after infusion.

This might include some side effects that you can’t see or feel. Blood tests are done regularly after gene therapy to check for these.

The risk of medium- and long-term side effects is low. However, it’s important that you are aware of them. These include:

  • The liver may temporarily become inflamed
  • The risk of blood clots may be higher
  • Fragments of gene therapy (virus shells) might be in your blood, semen, or bodily waste
  • Gene therapy could get into your DNA — a process called integration

There could also be other risks that are not yet known. Regular appointments are scheduled after your infusion to check that everything is okay.

Your doctor will explain the risks of HEMGENIX® in more detail.

If you get any side effects, talk to your doctor, pharmacist or nurse. This includes possible side effects not listed in the package leaflet. You can also report side effects directly via the Yellow Card Scheme. By reporting side effects, you can help provide more information on the safety of this medicine.

For a full list of side effects, please read the full HEMGENIX® Patient Information Leaflet.

FIX, factor X.

References

1. Pipe S et al. Long-Term Bleeding Protection, Sustained FIX Activity, Reduction of FIX Consumption and Safety of Hemophilia B Gene Therapy: Results from the HOPE-B Trial 3 Years after Administration of a Single Dose of Etranacogene Dezaparvovec in Adult Patients with Severe or Moderately Severe Hemophilia B. Blood. 2023;142(Suppl 1):1055. 2. HEMGENIX® (etranacogene dezaparvovec). Summary of product characteristics. 3. CSL Behring, Haemophilia Society. 2024. BEYOND Gene Therapy in Haemophilia B: Information, Guidance and Support.

Reporting side effects
If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in the package leaflet. You can also report side effects directly via the Yellow Card Scheme. By reporting side effects, you can help provide more information on the safety of this medicine.