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For people with the bleeding disorder hemophilia, the smallest bump, bruise, or cut can develop into a major health risk. Those living with hemophilia often spend their days with an ever-present concern hanging over their heads, as even the most mundane of activities can trigger a bleeding episode — or “bleeds” — and even one can be life-threatening. Without preventative treatment, repeated bleeds can be an even bigger concern. It’s a familiar struggle for John Thompson, whose life has been shaped by immediate and long-term health concerns related to his hemophilia.

“I’ve always craved activity — it’s who I am. But that physical activity resulted in a lot of bleeds. Over the years, those bleeds added up, leading to limitations like swelling and pain in my joints. Eventually, I had to slow down. As things got worse, I began to wonder if there was something different I could do.”

John Thompson

For decades, the only treatment available for hemophilia A, the most common form of the disorder, was infusion of factor VIII — a protein that is vital in the process of blood clotting and missing or defective in people with hemophilia A. However, approximately 1 in 5 people with hemophilia A will develop an antibody — called an inhibitor — to the medicine used to treat or prevent their bleeding episodes.1 The immune system identifies factor VIII replacements as foreign and produces the inhibitors to attack them, preventing these treatments from working. Before the introduction of Genentech’s hemophilia A treatment, patients who developed inhibitors had limited treatment options.

Hemlibra® (emicizumab-kxwh), which is approved in the U.S. to prevent or reduce the frequency of bleeding episodes in people of all ages with hemophilia A, is the first of a promising and potentially expanding treatment landscape.* Hemlibra works by replacing the function of activated factor VIII without being affected by inhibitors or prompting the immune system to create factor VIII inhibitors, which means it can allow the blood clotting process to continue in hemophilia A patients whether they have inhibitors or not.

“It’s really exciting to see patients take control of their hemophilia treatment. But as a research community, there is so much more we can — and must — do for patients.”

Richard Ko, a pediatric hematologist and executive medical director at Genentech

*What is the most important information I should know about HEMLIBRA? HEMLIBRA increases the potential for your blood to clot. Discontinue prophylactic use of bypassing agents the day before starting HEMLIBRA prophylaxis. Carefully follow your healthcare provider’s instructions regarding when to use an on-demand bypassing agent, and the dose and schedule you should use. HEMLIBRA may cause serious side effects when used with aPCC (FEIBA®), including thrombotic microangiopathy (TMA) and blood clots (thrombotic events). 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. See more safety information below.

An Additional Treatment Option for Hemophilia Patients

Since its initial FDA approval over five years ago, Hemlibra has become the most-prescribed prophylactic treatment available for hemophilia A, treating more than 19,000 people worldwide (according to IQVIA claims data from various insurance plan types from May 2021 – April 2022 and accounts for usage in prophylaxis settings in the US). It’s also the only FDA-approved hemophilia A medicine that can be self-administered as a shot under the skin, similar to the way someone with diabetes injects insulin. Alternative treatments must be directly infused into a vein, sometimes multiple times per week.

“The injections are usually pretty quick. I don’t have to struggle finding a vein, and I have more time to do other things,” Thompson said. “It’s surreal because at times, I forget that I have hemophilia. I know everyone’s experience can be different, but I haven’t had a bleed in a long time.”

Clinical research and years of real-world evidence continue to help Genentech understand the long-term impacts of hemophilia A and its treatments in an increasing range of people with the disorder. Building on over nine years of clinical study data, recent studies continue to explore the medicine’s impact across the hemophilia A population, providing new insights spanning infants, adolescents, and adults with the disease, as well as people living with mild or moderate hemophilia A. While treatment guidelines recommending early preventative care are well-established, there is an unmet need for infants from birth to one year of age. For these very young children, early prophylaxis may prevent long-term damage to joints and muscles and potentially reduce the risk of intracranial hemorrhage, which can be life-threatening.

For patients with chronic conditions like hemophilia, flexible dosing options are an important factor. Hemlibra has a unique four-week half-life,2 providing patients with sustained, effective levels of the medicine between doses, regardless of their age or selected dosing schedule.

After four initial weekly loading doses, Hemlibra has multiple dosing options, including once a week, once every two weeks and once every four weeks, allowing patients and their physicians to choose the appropriate treatment schedule for them. This flexibility has helped to establish Hemlibra as a viable, preventative option for hemophilia A patients.

For the team at Genentech, this isn’t the finish line. It’s a launchpad for further innovation that could continue to transform the treatment landscape for people with hemophilia.

Pushing A Crowded Field Forward

In 2017, Genentech introduced the first new class of medicine approved to treat hemophilia A in nearly 20 years. Since then, the treatment landscape has the potential to quickly evolve, with new medicines on the horizon. While many therapeutic companies might see this shift as a threat, Genentech recognizes the importance of advancing research and treatment options for patients and welcomes continued innovation. As an active partner to the hemophilia community, they have driven innovation when there were limited treatment options available — and will continue to press for safe, effective and accessible therapies for people living with hemophilia A.

“Our research and discovery is far from over,” Ko said. “We have a number of ongoing studies that were designed to answer some of the biggest questions remaining in hemophilia treatment, including its impact on physical activity and long-term bone and joint health.”

By conducting innovative clinical trials and studying patients’ real-world experience, Genentech continues to lay the groundwork for a new generation of hemophilia patients to have different expectations for what it means to live with the disorder.

“It’s very exciting to be part of a research community that is working in so many different areas to advance treatments,” Ko said. “There is more for us to learn and discover on behalf of this patient community. We’re seeing the momentum only continuing to build.”

Hemlibra U.S. 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.

Important Safety Information

What is the most important information to know about Hemlibra?

Hemlibra increases the potential for 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 one’s kidneys, brain, and other organs
  • Blood clots (thrombotic events), which may form in blood vessels in the arm, leg, lung, or head

Patients should talk to their 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 patients experience any of these symptoms during or after treatment with Hemlibra, they should get medical help right away.

Patients should carefully follow their 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, patients should talk to their healthcare provider in case they feel they need more than 100 U/kg of aPCC (Feiba®) total.

Patients’ bodies may make antibodies against Hemlibra, which may stop Hemlibra from working properly. Patients should contact their healthcare provider immediately if they notice that Hemlibra has stopped working for them (e.g., increase in bleeds).

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. Patients can speak with their healthcare provider for more information.

What else should patients know about Hemlibra?

Patients should see the detailed “Instructions for Use” that comes with 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. 

  • Patients should stop taking their prophylactic bypassing therapy the day before they start Hemlibra
  • Patients may continue taking their prophylactic factor VIII for the first week of Hemlibra

Hemlibra may interfere with laboratory tests that measure how well blood is clotting and create an inaccurate result. Patients should speak with their healthcare provider about how this may affect their care.

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

Patients should tell their healthcare provider about all the medicines they take, including prescription medicines, over-the-counter medicines, vitamins, or herbal supplements. Patients should keep a list of them to show their healthcare provider and pharmacist.

Before using Hemlibra, patients should tell their healthcare provider about all of their medical conditions, including if they 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 an 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 Side effects may also be reported 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.


1. Centers for Disease Control and Prevention. Inhibitors and Hemophilia. Accessed March 27, 2023.
2. National Library of Half Life. Accessed March 27, 2023.



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