Hemlibra (emicizumab-kxwh) is a prescription drug that helps prevent or reduce the frequency of bleeding episodes from hemophilia A. The drug comes as a solution for injecting under the skin every 1, 2, or 4 weeks.

Hemlibra is used to help prevent or reduce the frequency of bleeding episodes from hemophilia A. It’s approved for adults and children ages newborn and older who have hemophilia A with or without factor VIII inhibitors. Factor VIII is a certain protein in the body that helps blood clot. Factor VIII inhibitors are immune system proteins that attach to factor VIII and prevent it from forming blood clots.

The active ingredient in Hemlibra is emicizumab-kxwh. (An active ingredient is what makes a drug work.) Hemlibra belongs to a group of drugs called bispecific factor IXa- and factor X-directed antibodies.

This article describes the dosages of Hemlibra, as well as its strengths and how to use it. To learn more about Hemlibra, see this in-depth article.

The table below highlights the basics of Hemlibra’s dosage. All doses are listed in milligrams (mg). Body weight is listed in kilograms (kg).*

Recommended loading dosage• 3 mg/kg weekly for 4 weeks
Recommended maintenance dosage• 1.5 mg/mg weekly
• 3 mg/kg every 2 weeks
• 6 mg/kg every 4 weeks

* For reference, 1 kg is about 2.2 pounds (lb).

A loading dosage is what your doctor prescribes when you start using Hemlibra. It helps your body get a therapeutic amount of the drug rapidly. A maintenance dosage is what your doctor prescribes after the loading dosage to manage your condition.

Keep reading for more details about Hemlibra’s dosage.

What is Hemlibra’s form?

Hemlibra is available as a liquid solution that’s given as an injection under your skin.

What strengths does Hemlibra come in?

Hemlibra comes in six strengths that are measured in milligrams per milliliter of solution (mg/mL):

  • 12 mg/0.4 mL
  • 30 mg/mL
  • 60 mg/0.4 mL
  • 105 mg/0.7 mL
  • 150 mg/mL
  • 300 mg/2 mL

What are the usual dosages of Hemlibra in adults?

The information below describes dosages that are commonly used or recommended. But be sure to use the dosage your doctor prescribes for you. They’ll determine the best dosage to fit your needs.

Dosage for hemophilia A

Hemlibra is used in adults to help prevent or reduce the frequency of bleeding episodes from hemophilia A. It’s approved for adults who have hemophilia A with or without factor VIII inhibitors.

The typical Hemlibra dosage usually includes loading and maintenance dosages. Both are based on body weight in kg. Your doctor will determine the dosages that are best for you.

A loading dosage helps your body get a therapeutic amount of the drug rapidly. The typical loading dosage to start treatment is 3 mg/kg weekly for the first 4 weeks.

After the loading dosage, your doctor prescribes a maintenance dosage to manage your condition. The typical maintenance dosages are:

  • 1.5 mg/kg weekly
  • 3 mg/kg every 2 weeks
  • 6 mg/kg every 4 weeks

If you’re taking any bypassing agents,* you’ll likely stop the agent the day before you start Hemlibra.

If you’re taking a factor VIII product, your doctor may recommend you continue taking it during your first week of Hemlibra.

As a dosage example, assume a doctor prescribes Hemlibra for an adult weighing 75 kg (about 165 lb). Their loading dose would be 225 mg. Then the doctor prescribes a maintenance dose of 6 mg/kg every 4 weeks. So this person’s maintenance dosage would be 450 mg every 4 weeks.

* A bypassing agent is a blood product used to treat bleeding episodes in certain people.

What’s the dosage of Hemlibra for children?

Hemlibra is used in children to help prevent or reduce the frequency of bleeding episodes from hemophilia A. It’s approved for children ages newborn and older who have hemophilia A with or without factor VIII inhibitors.

The dosage used in children is the same as the dosage for adults. To learn more, see the “What are the usual dosages of Hemlibra in adults?” section above.

Is Hemlibra used long term?

Yes, Hemlibra is usually used as a long-term treatment. If you and your doctor determine that it’s safe and effective for your condition, you’ll likely use it long term.

The dosage of Hemlibra your doctor prescribes may depend on several factors. These include:

  • the type and severity of the condition the drug is used for
  • your age
  • your weight

Hemlibra doses are given as an injection under your skin. You may receive your injections at your doctor’s office. Or your doctor may teach you or a caregiver how to give the injections so you can do them at home.

Places to inject Hemlibra are your outer thigh, belly, and back of your arm (if someone else gives you the injection). Avoid injecting into irritated areas of skin. Be sure to rotate the areas where you inject Hemlibra. This means using a different area of the body for your current dose than the area you used for the last one.

Store Hemlibra in the refrigerator.

Injecting a dose

Remove Hemlibra from the refrigerator 15 minutes before you inject a dose.

When you’re ready to inject your dose, clean the area of skin where you’ll inject it. Use an alcohol wipe or swab, then let the area dry. Inject your dose as follows:

  1. Pull up the area of skin where you’ll inject your dose. Quickly and firmly press the needle into your skin. Your healthcare professional will tell you whether to insert the needle at a 45-degree or 90-degree angle.
  2. Once the needle is inserted, release your skin.
  3. Slowly push the plunger until it stops.
  4. Remove the needle at the same angle you inserted it.

For complete instructions, including how to fill your syringe before injecting, see the prescribing information. The drugmaker’s website also has multiple resources, including a quick-start guide.

For more information on the expiration, storage, and disposal of Hemlibra, talk with your doctor or pharmacist.

Accessible drug containers and labels

Some pharmacies provide medication labels that:

  • have large print
  • use braille
  • feature a code you can scan with a smartphone to change the text to audio

Your doctor or pharmacist may be able to recommend pharmacies that offer these accessibility features if your current pharmacy doesn’t.

If you miss a dose of Hemlibra, inject it as soon as possible. But do not inject two doses in the same day to make up for a missed dose. If you’re not sure whether you should inject a missed dose, talk with your doctor or pharmacist.

If you need help remembering to inject your dose of Hemlibra on time, try using a medication reminder. This can include setting an alarm or downloading a reminder app on your phone.

Do not use more Hemlibra than your doctor prescribes, as this can lead to harmful effects.

What to do in case you use too much Hemlibra

Call your doctor right away if you think you’ve used too much Hemlibra. You can also call 800-222-1222 to reach America’s Poison Centers or use its online resource. But if you have severe symptoms, immediately call 911 (or your local emergency number) or go to the nearest emergency room.

Below are answers to some commonly asked questions about Hemlibra’s dosage.

How long does it take for Hemlibra to start working?

It’s largely unknown how long it takes. In studies, people saw a reduction in bleeds after 24 weeks (about 6 months) of treatment. But the studies didn’t report when people first noticed a reduction in bleeds.

Your doctor will monitor you during treatment to check whether the drug is working for your condition.

If you have other questions about what to expect from your Hemlibra treatment, talk with your doctor.

Can Hemlibra be used for hemophilia B? If so, what’s the dosage?

No, Hemlibra is not used for hemophilia B.

People with hemophilia A or B lack a specific clotting factor, which is a type of protein in the blood. The missing clotting factor makes it harder for your blood to clot. If you have hemophilia A, you don’t have clotting factor VIII. But if you have hemophilia B, you don’t have clotting factor IX.

Since Hemlibra focuses on factor VIII, it wouldn’t be effective for hemophilia B. So the drugmaker doesn’t provide recommended dosages for this use.

If you’d like to learn more about treatment options for hemophilia B, talk with your doctor.

The sections above describe the usual dosages provided by Hemlibra’s drugmaker. If your doctor recommends this drug, they’ll prescribe the dosage that’s right for you.

Remember, you should not change your dosage of Hemlibra without your doctor’s recommendation. Only use Hemlibra exactly as prescribed. Talk with your doctor if you have questions or concerns about your current dosage.

Here are some examples of questions you may want to ask your doctor:

  • Rather than a maintenance dosage of 1.5 mg/kg weekly, can you prescribe 6 mg/kg every 4 weeks if that’s easier for me?
  • Will I need a higher dose of Hemlibra after I stop using a bypassing agent?
  • Can you increase my dosage if Hemlibra doesn’t seem to be working for me?

To learn more about Hemlibra, see this “Hemlibra (emicizumab)” article.

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Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.