Idelvion (coagulation factor IX [recombinant], albumin fusion protein) is a prescription drug used to treat and help prevent bleeding episodes in people with hemophilia B. Idelvion is given as an intravenous (IV) injection.

Idelvion is used for the following situations in adults and certain children with hemophilia B:

  • to treat bleeding episodes (also called “on-demand treatment”)
  • to control bleeding surrounding surgery
  • to help reduce the frequency of bleeding episodes

To learn more about Idelvion’s uses, see the “What is Idelvion used for?” section.

Idelvion basics

Idelvion contains a recombinant (lab-made) form of coagulation factor IX as its active ingredient. Coagulation factor IX is found in your blood.

Idelvion is a biologic drug, which means it’s made from parts of living organisms. It’s available only as a brand-name drug. It isn’t available in a biosimilar form. Biosimilars are like generic drugs, but unlike generics (which are made for nonbiologic drugs), biosimilars are made for biologics.

Idelvion is used in certain situations in adults and children with hemophilia B.

Hemophilia B is a rare genetic (inherited) condition where your blood has lower amounts of coagulation factor IX than usual. Coagulation factor IX helps your blood clot. If you have hemophilia B, your blood takes longer to clot, creating a bleeding episode. These bleeding episodes may be due to an injury or surgery, or they may occur from no clear cause.

In the shorter term, Idelvion is used to treat active bleeding episodes. It’s also used to control bleeding surrounding surgery. Idelvion can be used as a longer-term treatment to help reduce how often bleeding episodes happen.

Idelvion is not used to train your immune system to better utilize coagulation factor IX (a process called immune tolerance induction). Idelvion is a lab-made version of coagulation factor IX. By supplying more coagulation factor IX to your blood, Idelvion helps it to clot more efficiently.

Like most drugs, Idelvion may cause mild to serious side effects. The following lists contain some of the more common side effects Idelvion may cause, but they don’t include all possible side effects.

Keep in mind that side effects of a drug can depend on:

  • your age
  • other health conditions you have
  • the severity of your condition
  • other medications you take

Your doctor or pharmacist can tell you more about the potential side effects of Idelvion. They can also suggest ways to help reduce and manage them.

Mild side effects

Here’s a list of some of the mild side effects Idelvion can cause. To learn about other mild side effects, talk with your doctor or pharmacist or read Idelvion’s prescribing information.

Mild side effects of Idelvion that have been reported include:

Mild side effects of many drugs may go away within a few days to a couple of weeks. But if they become bothersome, talk with your doctor or pharmacist.

Serious side effects

Serious side effects from Idelvion can occur, but they aren’t common. If you have serious side effects from Idelvion, call your doctor right away. But if you think you’re having a medical emergency, call 911 or your local emergency number.

Idelvion is a lab-made form of coagulation factor IX. Other drugs containing recombinant forms of coagulation factor IX have serious side effects that are reported in Idelvion’s prescribing information. These side effects include:

ALLERGIC REACTION

Idelvion can cause an allergic reaction for some people based on the drug’s prescribing information.

In general, symptoms of allergic reaction can be mild or serious.

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms and can determine whether you should continue Idelvion treatment.

If you have symptoms of a severe allergic reaction, such as swelling or difficulty breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Idelvion, they may have you switch to a different treatment.

A healthcare professional usually gives you Idelvion in an office, hospital, or clinic, and your doctor will recommend the dosage that’s right for you.

In certain situations, a healthcare professional may train you or a caregiver to administer your dosage at home. If this happens, you’ll receive thorough instructions on the proper dosage.

The following are commonly used dosages, but your doctor will determine the dosage you’ll receive. Always inject the dosage your doctor prescribes.

Form and strengths

Idelvion comes as a powder in single-use vials. When it’s time for a dose, this powder is mixed into a liquid solution and given as an intravenous (IV) infusion (an injection into a vein given over time).

Idelvion is available in five strengths:

  • 250 international units (IU)
  • 500 IU
  • 1,000 IU
  • 2,000 IU
  • 3,500 IU

Recommended dosages

To treat active bleeding episodes, control bleeding surrounding surgery, or help reduce how often hemophilia B bleeding episodes occur, the dosage of Idelvion you’ll receive depends on the following factors:

  • your weight in kilograms (kg) — 1 kg equals about 2.2 pounds
  • location of the bleeding
  • the severity of the active bleeding or your hemophilia condition
  • your age
  • how you respond to Idelvion

Dosage for treatment of bleeding episodes

For “on-demand treatment” (treatment of active bleeding episodes), your dosage will also likely be based on bleeding severity:

  • For minor or moderate bleeding episodes (such as in your mouth or joint): You may receive a dose every 48 to 72 hours until bleeding stops. One dose typically heals most bleeding episodes in this category.
  • For major bleeding episodes (such as in your brain or certain parts of your hip): You may receive a dose every 48 to 72 hours for the first week. You may need treatment for 7 to 14 days to heal properly. After the first week, you may receive a dose once or twice per week until bleeding stops.

Your doctor may adjust your dosage based on how you respond to Idelvion.

Dosage to control bleeding surrounding surgery

To control bleeding surrounding surgery, your dosage will also be based on the type of surgery you’re preparing for:

  • For minor surgeries (such as in your mouth): One dose should provide adequate bleeding control for this category. But if you need more coverage, you may receive a dose every 48 to 72 hours until you heal.
  • For major surgeries (such as in your brain or throat): You may receive a dose every 48 to 72 hours for the first week. You may need treatment for 7 to 14 days, depending on your condition. If you need treatment after the first 7 days, you’ll receive a dose once or twice per week.

Your doctor may adjust your dosage based on how you respond to Idelvion.

Dosage to reduce the frequency of bleeding episodes

To help reduce how often bleeding episodes occur, your doctor will prescribe a dosage based on your weight.

The recommended dosage is 25 to 40 IU per kg of body weight (IU/kg) given once every 7 days. If you respond well to this dosage, your doctor may change it to 50 to 75 IU/kg given once every 14 days.

Your doctor may make further dosage adjustments based on your needs.

How it’s given

Idelvion comes as a powder in single-use vials. This powder is mixed into a liquid solution given as an IV infusion (an injection into a vein given over time). It’s usually given by a doctor or another healthcare professional in a hospital or clinic.

In certain situations, a healthcare professional will train you or a caregiver how to prepare and administer Idelvion doses at home. They’ll explain how much to use and how often. Be sure to follow these instructions.

For more information on how Idelvion is administered, check out the drug’s prescribing information or the drugmaker’s website.

Questions about receiving Idelvion

Here are some common questions about receiving Idelvion.

  • What if I miss a dose of Idelvion? If you miss a dose of Idelvion, call your doctor’s office as soon as possible for more guidance.
  • Will I need to use Idelvion long term? Maybe. If you’re using the drug to help reduce how often bleeding episodes happen and it’s safely and effectively treating your condition, you may use it long term. If you’re receiving Idelvion to treat active bleeding episodes or to control bleeding surrounding surgery, Idelvion will likely be a short-term treatment.
  • How long does Idelvion take to work? Idelvion begins to work after one dose. But you may not notice its effects for up to 7 to 14 days, depending on why you’re taking the drug. Your doctor will order tests throughout your treatment to make sure the drug is working to treat your condition.

Overdose

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

What to do in case you inject too much Idelvion

Call your doctor if you think you’ve injected too much Idelvion. 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.

Consider the following information before starting Idelvion treatment.

Interactions

Taking a drug with certain medications, vaccines, foods, and other things can affect how the drug works. These effects are called interactions.

Idelvion is not known to interact with other medications, herbs, supplements, foods, or alcohol. The manufacturer did not list any interactions in the drug’s prescribing information.

Before starting Idelvion treatment, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also tell them about any vitamins, herbs, and supplements you take. Sharing this information can help you avoid potential interactions.

If you have questions about drug interactions that may affect you, talk with your doctor or pharmacist.

Pregnancy and breastfeeding

It’s not known whether Idelvion treatment is safe during pregnancy or while breastfeeding.

If you’re pregnant or breastfeeding, or planning to become pregnant or to breastfeed, talk with your doctor before starting this medication.

Warnings

Idelvion can sometimes cause harmful effects in people with certain conditions. This is known as a drug-condition interaction. Other factors may also affect whether this drug is a treatment option for you.

Talk with your doctor about your health history before starting Idelvion. Be sure to tell them if any of the following factors apply to you:

  • blood tests have shown you have antibodies to coagulation factor IX, which may make Idelvion less effective
  • previous allergic reaction to any ingredients in Idelvion, including hamster proteins
  • pregnancy
  • breastfeeding

Whether you have health insurance or not, cost may be a factor when you’re considering Idelvion. What you’ll pay for this medication may depend on several factors, such as your treatment plan and the pharmacy you use.

If a healthcare professional has trained you or a caregiver on how to receive doses at home, you’ll also need to plan on buying needles and syringes.

If you have questions about how to pay for your prescription, talk with your doctor or pharmacist. A program called Idelvion Connect may also be available.

Learn more about saving on your prescriptions.

Other drugs are available that can treat your condition. If you’d like to explore an alternative to Idelvion, talk with your doctor. They can tell you about other medications that might work well for you.

Like Idelvion, the following drugs are also lab-made forms of coagulation factor IX:

  • Alprolix
  • BeneFix
  • Ixinity
  • Rebinyn
  • Rixubis

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.