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Our Commitment to Providing Updated and Timely Scientific and Clinical Information About Emicizumab-kxwh

This website is intended to provide community members with balanced clinical and scientific information on the safety and effectiveness of emicizumab-kxwh for educational purposes, and to support informed and meaningful treatment discussions with healthcare providers.


The US Package Insert (Prescribing Information (Pl) or label) provides FDA-approved information about prescription medications and is the primary source of information about emicizumab. 

The information on this site is not meant to take the place of important conversations with your healthcare provider. Your healthcare provider should be the primary source of information about your medical condition and the safe and effective use of any medicine, including emicizumab. 

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An update from Genentech on Hemlibra® post-approval data communication process and site update

To the hemophilia community, 

At Genentech, we recognize and appreciate the ongoing conversation within the hemophilia community around the long-term efficacy and safety of Hemlibra® (emicizumab-kxwh). We understand that the subject of long-term safety for hemophilia treatments is an important topic for this community and we remain committed to listening to you and providing information that leads to informed clinical decision making and patient care.

Genentech’s first U.S. medical websites for Hemlibra were originally launched in 2018 to provide updated, verified safety information to the hemophilia community, specifically related to adverse events (AEs) of interest, whether or not such events were related to Hemlibra. Today, Hemlibra is approved and available for people with hemophilia A in more than 90 countries and more than 7,200 patients around the world have been treated with Hemlibra. We now have much broader availability of information from databases and individual experiences, and the source of safety information has expanded from controlled clinical trial reporting to ongoing voluntary adverse event reporting by healthcare professionals, patients and their caregivers. That’s why we’ve launched updated versions of our medical websites and we’ve evolved our process for reporting post-approval information on Hemlibra to ensure transparency and meet the community’s expectations for information.

The updated U.S. Hemlibra medical sites — for patients and for physicians — now provide broader clinical information on the efficacy and safety of Hemlibra. On these sites, we will report data from ongoing studies and real-world use of Hemlibra that are presented at scientific meetings and published in medical journals, as these data are available. Importantly, any future updates on Hemlibra will be appropriately benchmarked, peer reviewed and medically relevant.

We made this decision after actively engaging and working closely with the hemophilia medical and patient communities to understand what would be most impactful. This means that, together with members of the scientific community, we can provide a broader body of data in place of the quarterly data updates previously reported. In addition, Hemlibra’s label, as approved by the U.S. Food and Drug Administration (FDA), should always be the primary source of information on the safety and efficacy of the medicine.

Our commitment to providing timely and transparent updates on Hemlibra to the hemophilia community remains unchanged. We will continue to listen, respond and partner with you, so that together we can lead this collective effort for a continued dialogue allowing us to protect patient safety and put this community first.

Contact Information

Report a Side Effect

(888) 835-2555
(24 hrs/day, 7 days/week)

(800) FDA-1088
(24 hrs/day, 7 days/week)

Medicine Information Support

(800) 821-8590

Monday – Friday
5:00am – 5:00pm PT

Report a Product Complaint (product quality issue or product abnormality)

(800) 334-0290

Monday – Friday
5:00am – 5:00pm PT

Important Safety Information & Indication


HEMLIBRA is a prescription medicine used for routine prophylaxis to prevent or reduce the frequency of bleeding episodes in adults and children, ages newborn and older, with hemophilia A with or without factor VIII inhibitors.

What is the most important information I should know about HEMLIBRA?

HEMLIBRA increases the potential for your blood to clot. People who use activated prothrombin complex concentrate (aPCC; Feiba®) to treat breakthrough bleeds while taking HEMLIBRA may be at risk of serious side effects related to blood clots.

These serious side effects include: 

Thrombotic microangiopathy (TMA), a condition involving blood clots and injury to small blood vessels that may cause harm to your kidneys, brain, and other organs

Blood clots (thrombotic events), which may form in blood vessels in your arm, leg, lung, or head

Talk to your doctor about the signs and symptoms of these serious side effects, which can include:

  • Confusion
  • Stomach, chest, or back pain
  • Weakness
  • Nausea or vomiting
  • Swelling, pain, or redness
  • Feeling sick or faint
  • Decreased urination
  • Swelling of arms and legs
  • Yellowing of skin and eyes
  • Eye pain, swelling, or trouble seeing
  • Fast heart rate
  • Numbness in your face
  • Headache
  • Shortness of breath
  • Coughing up blood
If you experience any of these symptoms during or after treatment with HEMLIBRA, get medical help right away.

Carefully follow your healthcare provider’s instructions regarding when to use an on-demand bypassing agent or factor VIII, and the dose and schedule to use for breakthrough bleed treatment. If aPCC (Feiba®) is needed, talk to your healthcare provider in case you feel you need more than 100 U/kg of aPCC (Feiba®) total.

The most common side effects of HEMLIBRA include: injection site reactions (redness, tenderness, warmth, or itching at the site of injection), headache, and joint pain. These are not all of the possible side effects of HEMLIBRA. You can speak with your healthcare provider for more information.

What else should I know about HEMLIBRA?

See the detailed “Instructions for Use” that comes with your HEMLIBRA for information on how to prepare and inject a dose of HEMLIBRA, and how to properly throw away (dispose of) used needles and syringes.
  • Stop taking your prophylactic bypassing therapy the day before you start HEMLIBRA
  • You may continue taking your prophylactic factor VIII for the first week of HEMLIBRA
HEMLIBRA may interfere with laboratory tests that measure how well your blood is clotting and create an inaccurate result. Speak with your healthcare provider about how this may affect your care.

Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Only use HEMLIBRA for the condition it was prescribed. Do not give HEMLIBRA to other people, even if they have the same symptoms that you have. It may harm them.

Tell your healthcare provider about all the medicines you take, including prescription medicines, over-the-counter medicines, vitamins, or herbal supplements. Keep a list of them to show your healthcare provider and pharmacist.

Before using HEMLIBRA, tell your healthcare provider about all of your medical conditions, including if you are pregnant, plan to become pregnant, are breastfeeding, or plan to breastfeed.

Since HEMLIBRA was tested in males, there is no information on whether HEMLIBRA may impact your unborn baby or breast milk. Females who are able to become pregnant should use birth control during treatment.

Side effects may be reported to the FDA at (800) FDA-1088 or
You may also report side effects to Genentech at (888) 835-2555.

Please see Important Safety Information, including Serious Side Effects, as well as the HEMLIBRA full Prescribing Information and Medication Guide.