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hemgenix-logo-bg mobile-menu-bg HEMGENIX® (etranacogene dezaparvovec-drlb)
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the app

HEMGENIX DNA Spiral with People holding hands
factor IX level of
37% for years
Patient portrayal;
intended for women

Proven safe and effective. Studied in clinical trials since 2018.


A one-time infusion delivers greater bleed protection*

HEMGENIX DNA Spiral with People holding hands

*In the clinical trial, annualized bleed rate (ABR) for all bleeds
decreased from an average of 4.1 for patients on
prophylaxis (prophy) during the lead-in period to 1.9 (54% reduction)
in months 7-18 after treatment.

See the long-term results for
people who have taken

Find out what you can expect from
treatment with HEMGENIX

You may be eligible for HEMGENIX if you’re
an adult with hemophilia B and you:

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Currently use factor IX prophylaxis (prophy) therapy

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ORhave current or historical life-threatening bleeding,

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ORhave repeated, serious spontaneous bleeding episodes

  • Have poor venous access or require a port
  • Feel limited by or have issues with infusion schedule
  • Feel that current treatment is not meeting goals
  • Have no factor IX inhibitors
  • Are looking for an innovative treatment option

Download BSupport App logo app for tracking every step of your journey

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  • Track your current treatment; see if gene therapy may be right for you
  • Stay up to date on relevant information and manage your treatment journey
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HEMGENIX®, etranacogene dezaparvovec-drlb, is a one-time gene therapy for the treatment of adults with hemophilia B who:

  • Currently use Factor IX prophylaxis therapy, or
  • Have current or historical life-threatening bleeding, or
  • Have repeated, serious spontaneous bleeding episodes.

HEMGENIX is administered as a single intravenous infusion and can be administered only once.

What medical testing can I expect to be given before and after administration of HEMGENIX?

To determine your eligibility to receive HEMGENIX, you will be tested for Factor IX inhibitors. If this test result is positive, a retest will be performed 2 weeks later. If both tests are positive for Factor IX inhibitors, your doctor will not administer HEMGENIX to you. If, after administration of HEMGENIX, increased Factor IX activity is not achieved, or bleeding is not controlled, a post-dose test for Factor IX inhibitors will be performed.

HEMGENIX may lead to elevations of liver enzymes in the blood; therefore, ultrasound and other testing will be performed to check on liver health before HEMGENIX can be administered. Following administration of HEMGENIX, your doctor will monitor your liver enzyme levels weekly for at least 3 months. If you have preexisting risk factors for liver cancer, regular liver health testing will continue for 5 years post-administration. Treatment for elevated liver enzymes could include corticosteroids.

What were the most common side effects of HEMGENIX in clinical trials?

In clinical trials for HEMGENIX, the most common side effects reported in more than 5% of patients were liver enzyme elevations, headache, elevated levels of a certain blood enzyme, flu-like symptoms, infusion-related reactions, fatigue, nausea, and feeling unwell. These are not the only side effects possible. Tell your healthcare provider about any side effect you may experience.

What should I watch for during infusion with HEMGENIX?

Your doctor will monitor you for infusion-related reactions during administration of HEMGENIX, as well as for at least 3 hours after the infusion is complete. Symptoms may include chest tightness, headaches, abdominal pain, lightheadedness, flu-like symptoms, shivering, flushing, rash, and elevated blood pressure. If an infusion-related reaction occurs, the doctor may slow or stop the HEMGENIX infusion, resuming at a lower infusion rate once symptoms resolve.

What should I avoid after receiving HEMGENIX?

Small amounts of HEMGENIX may be present in your blood, semen, and other excreted/secreted materials, and it is not known how long this continues. You should not donate blood, organs, tissues, or cells for transplantation after receiving HEMGENIX.

Please see full prescribing information for HEMGENIX.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit, or call 1-800-FDA-1088.

You can also report side effects to CSL Behring’s Pharmacovigilance Department at 1-866-915-6958.