Kalbitor is a brand-name prescription medication. It’s FDA-approved for the acute treatment of hereditary angioedema (HAE) attacks. “Acute” means the drug is used to treat attacks immediately. Kalbitor is approved for use in adults as well as children ages 12 years and older.

HAE is a rare condition that causes periods of sudden and severe swelling deep in your skin or other tissues. These periods are known as attacks. HAE is typically inherited (passed down genetically through families).

Drug details

Kalbitor contains the active drug ecallantide and belongs to the drug class known as plasma kallikrein inhibitors. (A drug class is a group of medications that have similar effects or uses.)

Kalbitor comes as a liquid solution in single-dose vials. The drug is given by a healthcare professional as a subcutaneous injection (an injection just under your skin). You’ll receive Kalbitor only to treat an attack of HAE. The drug is not approved to help prevent HAE attacks.

Kalbitor is available in one strength: 10 milligrams (mg) per 1 milliliter (mL).

Effectiveness

For information about the effectiveness of Kalbitor, see the “Kalbitor uses” section below.

Kalbitor’s active drug is a protein called ecallantide. Because ecallantide is a protein, Kalbitor is considered to be a biologic medication. And it’s available only as a brand-name biologic drug.

Biologic drugs don’t have generic forms. Instead, they may have approved biosimilar forms. However, Kalbitor doesn’t have an approved biosimilar.

Biosimilar drugs are similar to brand-name biologics (their parent drug). But unlike generics, which are made from chemicals, biosimilars aren’t exact copies of their parent drug. This is because they’re made from live sources, and this process creates small differences.

That said, approved biosimilars are considered as safe and effective as their parent biologic. Biosimilars are also often less expensive than their parent drug.

As with all medications, the cost of Kalbitor can vary. To find current prices for Kalbitor in your area, check out WellRx.com.

The cost you find on WellRx.com is what you may pay without insurance. The actual price you’ll pay depends on your insurance plan, your location, and the specialty pharmacy you use.

It’s important to note that you’ll have to get Kalbitor through a specialty pharmacy, which will send the drug to a healthcare facility or healthcare professional on your behalf. A specialty pharmacy is authorized to carry specialty medications. These are drugs that may be expensive or may require help from healthcare professionals to be used safely and effectively. In some cases, you may get the drug directly from the healthcare facility or healthcare professional.

Before approving coverage for Kalbitor, your insurance company may require you to get prior authorization. This means that your doctor and insurance company will need to communicate about your prescription before the insurance company will cover the drug. The insurance company will review the prior authorization request and decide if the drug will be covered.

If you’re not sure if you’ll need to get prior authorization for Kalbitor, contact your insurance company.

Financial and insurance assistance

If you need financial support to pay for Kalbitor, or if you need help understanding your insurance coverage, help is available.

Takeda Pharmaceutical Company, the manufacturer of Kalbitor, offers a program called OnePath Product Support. Through this program, you may find copay assistance for Kalbitor. For more information and to find out if you’re eligible for support, call 866-888-0660 or visit the program website.

If you don’t have insurance, ask your doctor or pharmacist about other financial support options.

Generic or biosimilar version

Kalbitor is only available as a brand-name biologic medication.

Biologic drugs don’t have generic forms. Instead, they may have approved biosimilar forms. However, Kalbitor doesn’t have an approved biosimilar.

Biosimilar drugs are similar to brand-name biologics (their parent drug). But unlike generics, which are made from chemicals, biosimilars aren’t exact copies of their parent drug. This is because they’re made from live sources, and this process creates small differences.

That said, approved biosimilars are thought to be just as safe and effective as their parent biologic. And they typically cost less than their parent drug. Biosimilars are also often less expensive than their parent drug.

Your doctor will recommend a Kalbitor dosage for your hereditary angioedema (HAE) attacks based on several factors. These may include:

  • your age
  • whether your symptoms ease after the first dose
  • whether you have serious side effects

The following information describes dosages that are commonly used or suggested for Kalbitor. However, be sure to follow the HAE treatment plan that your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

Drug forms and strengths

Kalbitor comes as a liquid solution in single-dose vials. The drug is given by a healthcare professional as a subcutaneous injection (an injection just under your skin).

Kalbitor is available in one strength: 10 milligrams (mg) per 1 milliliter (mL).

Dosage for hereditary angioedema

Kalbitor is used for the acute treatment of hereditary angioedema (HAE) attacks. “Acute” means the drug is used to treat attacks immediately.

For this purpose, the Kalbitor dose is three 10-mg injections for a total dose of 30 mg. Unless you have severe side effects, the healthcare professional will give you all three shots in a row.

You’ll receive the injections in your abdomen (belly), thigh, or upper arm. The healthcare professional can inject them into the same area or change spots. But they typically won’t inject within 2 inches (5 centimeters) of areas where attack symptoms are occurring.

In some cases, you may still have symptoms of an HAE attack after receiving a dose of Kalbitor. If you do, you can be given another 30-mg dose within 24 hours of your first dose.

Kalbitor may cause a serious allergic reaction called anaphylaxis.* Because of this, you’ll receive Kalbitor injections only in a medical setting where anaphylaxis and HAE can be treated.

* Kalbitor has a boxed warning for anaphylaxis. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). To learn more, see “Allergic reaction” in the “Kalbitor side effects” section below.

Children’s dosage

Kalbitor is used for the acute treatment of HAE attacks in children ages 12 years and older. The dosage for children is the same as the dosage for adults. For those details, see “Dosage for hereditary angioedema” above.

What if I miss a dose?

Kalbitor is an acute HAE treatment. This means you’ll be given the drug only when you need immediate treatment for an attack. Kalbitor is not used to help prevent HAE attacks.

Will I need to use this drug long term?

HAE is a chronic (long-term) condition, so you may have HAE attacks throughout your lifetime. Kalbitor is meant to be used when you have an attack. If you and your doctor decide that the drug is a good option for you, Kalbitor will typically be a part of your long-term HAE treatment plan.

Kalbitor can cause mild or serious side effects. The following lists contain some of the key side effects that may occur during Kalbitor treatment. These lists don’t include all possible side effects.

For more information about the possible side effects of Kalbitor, talk with your doctor or pharmacist. They can give you tips on how to deal with any side effects that may be concerning or bothersome.

Note: The Food and Drug Administration (FDA) tracks side effects of drugs it has approved. If you would like to notify the FDA about a side effect you’ve had with Kalbitor, you can do so through MedWatch.

Mild side effects

Mild side effects* of Kalbitor can include:

  • headache
  • digestive problems,† such as nausea and diarrhea
  • fever
  • common cold or cold symptoms,† such as a stuffy nose
  • injection site reactions† (reactions where the drug was injected)

Most of these side effects are manageable or they may go away after treatment. But if they become more severe or don’t go away, talk with your doctor or pharmacist.

* To learn more about mild side effects of Kalbitor, talk with your doctor or pharmacist. You can also refer to Kalbitor’s prescribing information.
† For more information on this side effect, see “Side effect details” below.

Serious side effects

Serious side effects from Kalbitor aren’t common, but they can occur. Call your doctor right away if you have serious side effects. Call 911 or your local emergency number if your symptoms feel life threatening or if you think you’re having a medical emergency.

Serious side effects can include:

* Kalbitor has a boxed warning for anaphylaxis. A boxed warning is the most serious warning from the FDA. To learn more, see “Allergic reaction” in “Side effect details” below.

Side effects in children

Kalbitor is approved for use in children ages 12 years and older. In clinical studies, side effects were the same in both children and adults. For more details about possible side effects, see “Mild side effects” and “Serious side effects” above.

Side effect details

Here are some details on certain side effects this drug may cause.

Fever and colds

Fever may occur with Kalbitor treatment. The common cold or cold symptoms, such as a stuffy nose, may also occur. These are common side effects of the drug.

If you develop a high fever while using Kalbitor, talk with your doctor. A high fever is typically 103°F (39.4°C) or higher. They may suggest an over-the-counter (OTC) drug to help lower it. Examples of such OTC drugs include ibuprofen (Advil, Motrin) and acetaminophen (Tylenol).

You should also talk with your doctor if you develop bothersome cold symptoms, such as a stuffy nose or cough. They may suggest other OTC drugs, such as a nasal decongestant or cough suppressant.

Keep in mind that fever, a stuffy nose, and cough can also be symptoms of a serious allergic reaction called anaphylaxis. In fact, Kalbitor has a boxed warning for anaphylaxis. A boxed warning is the most serious warning from the FDA. (To learn more, see “Allergic reaction” below.) If your symptoms get worse or seem life threatening, call 911 or your local emergency number, or get emergency care right away.

Digestive problems

Kalbitor treatment may cause nausea, diarrhea, vomiting, and belly pain. Digestive problems are common with Kalbitor use.

Nausea and diarrhea were common side effects reported in two studies of ecallantide (Kalbitor’s active ingredient). In these studies, ecallantide was given as a subcutaneous injection. Vomiting and belly pain were common side effects reported in studies that included ecallantide. In these studies, ecallantide was given as a subcutaneous injection and as an intravenous (IV) injection. IV injections are given into a vein.

Keep in mind that hereditary angioedema attacks can also affect your digestive system and cause symptoms such as belly pain. So you shouldn’t self-treat or ignore severe digestive problems. Be sure to talk with your doctor or get medical care right away.

If your doctor determines that Kalbitor is causing the digestive problems, they may recommend a prescription or OTC drug to treat nausea, vomiting, or diarrhea. If you’re dehydrated due to any of these side effects, your doctor may recommend drinking an electrolyte solution.

Injection site reactions

Reactions may occur in the area where Kalbitor is injected. These reactions are a common side effect of Kalbitor.

Symptoms of injection site reactions can include:

  • skin irritation
  • redness or deepening of skin color
  • swelling
  • itching or rash
  • bruising
  • pain

Injection site reactions may occur right after you receive injections or later on. But they’re usually mild, temporary, and can be managed. If you have mild symptoms that bother you, talk with your doctor.

Keep in mind that symptoms of an injection site reaction may be similar to those of an allergic reaction or HAE attack, such as swelling or rash. Both conditions can be medical emergencies. In fact, Kalbitor may cause a serious allergic reaction called anaphylaxis.*

If you have symptoms that get worse or feel life threatening, immediately call 911 or your local emergency number, or get emergency medical care.

* Kalbitor has a boxed warning for anaphylaxis. A boxed warning is the most serious warning from the FDA. To learn more, see “Allergic reaction” below.

Allergic reaction

Although rare, some people can have an allergic reaction to Kalbitor treatment. The drug may also increase the risk of a serious allergic reaction called anaphylaxis. In fact, Kalbitor has a boxed warning for anaphylaxis. A boxed warning is the most serious warning from the FDA. The warning alerts doctors and patients about drug effects that may be dangerous.

Due to this risk, you’ll receive Kalbitor injections only from a healthcare professional in a medical setting where anaphylaxis and hereditary angioedema (HAE) can be treated. The symptoms of anaphylaxis can be similar to those of an HAE attack, so you’ll be monitored closely.

Tell the healthcare professional right away if you have any symptoms during or shortly after your Kalbitor treatment. Symptoms of anaphylaxis are more common within 1 hour of receiving the drug. The symptoms can include:

  • wheezing, shortness of breath, or trouble breathing
  • cough or chest tightness
  • dizziness, feeling faint, or a weak or fast heartbeat
  • feeling nervous
  • facial flushing, redness, or swelling
  • skin itching, hives, or warm skin
  • a tight throat, swelling of your throat or tongue, or trouble swallowing
  • runny nose, congestion, or sneezing

It’s also possible to have symptoms of a mild allergic reaction when using Kalbitor. These symptoms can include:

  • skin rash
  • itchiness
  • flushing

Call your doctor right away if you have any allergy symptoms with Kalbitor, as the reaction could become severe. Call 911 or your local emergency number if your symptoms feel life threatening or if you think you’re having a medical emergency.

Keep in mind that if you’ve had an allergic reaction to Kalbitor in the past, you shouldn’t receive the drug again.

Other drugs are available to treat hereditary angioedema (HAE). Some medications are used to help prevent HAE attacks while others are used as immediate relief for attacks. Drugs used as immediate relief may be known as acute treatments. Kalbitor is a type of acute HAE treatment.

Some HAE drugs may be a better fit for you than others. If you’re interested in finding an alternative to Kalbitor, talk with your doctor. They can tell you about other options that may work well for you.

Note: Some of the drugs listed here are used off-label to treat these specific conditions. Off-label drug use is when an FDA-approved drug is used for a purpose other than what it’s approved for.

Drugs used to help prevent HAE attacks

Examples of drugs that may be used to prevent HAE attacks include:

Drugs used for the acute treatment of HAE attacks

Examples of drugs that may be used for the acute treatment of HAE attacks include:

  • C1 esterase inhibitor, human (Berinert)
  • C1 esterase inhibitor, recombinant (Ruconest)
  • icatibant (Firazyr)
  • tranexamic acid

Kalbitor comes as a liquid solution in single-dose vials. The drug is given by a healthcare professional as a subcutaneous injection (a shot just under your skin). You’ll receive Kalbitor to treat hereditary angioedema (HAE) attacks.

You’ll receive the injections in your abdomen (belly), thigh, or upper arm. The healthcare professional can inject them into the same area or change spots. But they typically won’t inject within 2 inches (5 centimeters) of areas where attack symptoms are occurring. Unless you have severe side effects, you’ll receive all three shots in a row.

If your symptoms don’t ease, you may receive three more injections within 24 hours. The healthcare professional can give the injections into the same areas as the first dose or different ones.

Kalbitor may cause a serious allergic reaction called anaphylaxis.* Because of this, you’ll receive the injections only in a medical setting where anaphylaxis and HAE can be treated.

* Kalbitor has a boxed warning for anaphylaxis. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). To learn more, see “Allergic reaction” in the “Kalbitor side effects” section above.

When it’s administered

You’ll receive Kalbitor injections only when you need immediate treatment for an HAE attack. The drug is not approved to help prevent HAE attacks.

You should seek treatment as soon as you notice symptoms of an HAE attack, even if they don’t seem severe. It’s possible that your symptoms could worsen. Keep in mind that you can receive Kalbitor injections only from a healthcare professional in a medical setting where HAE and anaphylaxis* can be treated.

If you have an HAE attack that involves swelling in your face or throat, immediately call 911 or your local emergency number, or get emergency medical care. These symptoms could be life threatening.

* Kalbitor has a boxed warning for anaphylaxis. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). To learn more, see “Allergic reaction” in the “Kalbitor side effects” section above.

Kalbitor treatment and food

You can receive Kalbitor injections on a full or empty stomach. Eating food doesn’t affect how your body responds to the drug.

But if you notice symptoms of an HAE attack, especially swelling in your face or throat, you shouldn’t eat or drink anything. During an attack, food and beverages could block your airways, which could cause choking and make it harder to breathe.

Kalbitor is approved for the acute treatment of hereditary angioedema (HAE) attacks in adults and certain children. To learn more about HAE, see the “Kalbitor uses” section below.

Kalbitor belongs to a drug class* called plasma kallikrein inhibitors. (A drug class is a group of medications that have similar effects or uses.) Here’s a brief explanation of Kalbitor’s mechanism of action (how the drug works).

Bradykinin is a protein that causes fluid buildup, swelling, and pain during an HAE attack. Kalbitor lowers the level of bradykinin by blocking the activity of another blood protein called plasma kallikrein. The protein kallikrein normally tells your body to make more bradykinin. So, when the activity of plasma kallikrein is blocked, your body can’t make bradykinin. This, in turn, prevents fluid buildup and HAE attack symptoms such as swelling and pain.

How long does it take to work?

Kalbitor starts working soon after it’s injected into your body. But it may take hours for your symptoms to ease. In clinical studies, people treated with Kalbitor had a significant decrease in the severity of their attack symptoms 4 hours after their dose.

The Food and Drug Administration (FDA) approves prescription drugs such as Kalbitor to treat certain conditions. Kalbitor may also be used off-label for other conditions. Off-label drug use means using a drug for a purpose other than what it’s been approved for by the FDA.

Kalbitor is FDA-approved for the acute treatment of hereditary angioedema (HAE) attacks.

  • “Acute” means the drug is used to treat attacks immediately. Acute treatment may also be called on-demand treatment.
  • “Hereditary” means the condition is typically inherited (passed down genetically through families).
  • “Angioedema” refers to the fluid buildup and swelling that occurs during an attack.

Kalbitor is for use in adults as well as children ages 12 years and older.

About hereditary angioedema

HAE is a rare but serious condition. In the most common type of HAE, the body doesn’t make enough of a blood protein called C1-inhibitor. In another type, the body’s C1-inhibitor doesn’t work properly.

When the level of this protein is low or the protein doesn’t work, your body makes too much of another protein called bradykinin. When the level of bradykinin is too high, it triggers an HAE attack and its symptoms, such as:

  • fluid buildup and swelling, deep within your skin or tissues
  • rash or large welts
  • pain
  • trouble breathing or a hoarse voice

HAE attacks can affect many body parts, such as the face, throat, limbs, hands, and feet. The attacks can also affect the genitals and abdomen (belly) or digestive system. HAE attacks often occur suddenly, and symptoms may last for several days if untreated. Swelling that occurs in the face or throat can be life threatening, so it requires emergency medical care.

Symptoms of HAE attacks may be similar to those of an allergic reaction.

Treatment for hereditary angioedema

In general, treatment for HAE is tailored to each person’s needs. In addition to receiving medication (such as Kalbitor) for sudden attacks, your treatment plan may include:

  • Learning your triggers. Your doctor may suggest you keep an HAE attack diary to learn more about your symptoms, including what triggers them.
  • Preventing attacks. Your doctor may suggest treatment that you should use on a regular basis to help prevent HAE attacks. (To learn more, see the “Kalbitor alternatives” section above.)

Effectiveness for hereditary angioedema

In two clinical studies, Kalbitor was effective as an acute treatment of moderate to severe HAE attacks. The attacks occurred in the abdomen, feet, face, hands, genitals, or throat. For details, you can refer to Kalbitor’s prescribing information.

Guidelines from the U.S. Hereditary Angioedema Association recommend Kalbitor as a first-line, acute treatment for HAE attacks. (“First-line” refers to the first treatment used for a condition.)

Kalbitor and children

Kalbitor is approved for use in children ages 12 years and older.

Children ages 16 and 17 years were included in clinical studies of Kalbitor. The children had similar results to adults for the acute treatment of HAE attacks. Based on the results of these studies, researchers determined that the drug was also effective for use in children ages 12 to 15.

Kalbitor doesn’t interact with alcohol.

However, alcohol may worsen certain side effects of Kalbitor, such as headache, nausea, or diarrhea.* So you may want to avoid drinking alcohol after treatment with Kalbitor or while recovering from a hereditary angioedema (HAE) attack.

Also, consuming alcohol may be a trigger for HAE attack in some people. If alcohol is a trigger for your HAE attacks, your doctor may advise you against drinking it.

If you have questions about alcohol use during your Kalbitor treatment, talk with your doctor.

* For more information on side effects, see the “Kalbitor side effects” section above.

It’s not known if Kalbitor interacts with any medications. Studies of drug interactions haven’t been done for Kalbitor. It’s also not known if Kalbitor interacts with any herbs, supplements, or foods.

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

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

It’s not known if Kalbitor treatment is safe during pregnancy. The drug hasn’t been studied in pregnant females.* However, no negative effects have been reported in pregnant females treated with Kalbitor since the drug was released onto the market.

In a study of Kalbitor in animals, the drug didn’t cause birth defects. However, Kalbitor did cause some cases of early pregnancy loss. Keep in mind that animal studies don’t always predict the effects in humans.

If you’re pregnant or planning to become pregnant, talk with your doctor about whether Kalbitor or a different drug may be right for you.

* Sex and gender exist on spectrums. Use of the term “female” in this article refers to sex assigned at birth.

It’s not known if Kalbitor treatment is safe during pregnancy. If you’re sexually active and you or your partner can become pregnant, talk with your doctor about your birth control needs with Kalbitor.

For more information about Kalbitor treatment during pregnancy, see the “Kalbitor and pregnancy” section above.

It’s not known if Kalbitor treatment is safe while breastfeeding. It’s also not known if the drug passes into breast milk.

If you’re breastfeeding or planning to breastfeed, talk with your doctor before receiving Kalbitor. They can review the pros and cons of the medication with you. Your doctor can also advise you on healthy ways to feed your child.

Here are answers to some frequently asked questions about Kalbitor.

Does Kalbitor help prevent attacks from hereditary angioedema?

No, Kalbitor isn’t used to help prevent hereditary angioedema (HAE) attacks. Kalbitor is approved for the acute treatment of HAE attacks. “Acute” means the drug is used to treat attacks immediately.

For a list of some drugs that are used to help prevent HAE attacks, see the “Kalbitor alternatives” section above.

If you have questions about Kalbitor, or about preventing or treating HAE, talk with your doctor.

Can I give Kalbitor injections to myself?

No, you shouldn’t self-inject Kalbitor.

Kalbitor can cause a serious allergic reaction called anaphylaxis.* So only a healthcare professional should give you the injections. In fact, you’ll need to receive them in a medical setting where anaphylaxis and hereditary angioedema (HAE) can be treated.

If you’re interested in an HAE treatment that you can self-inject, talk with your doctor about a drug called Firazyr. Keep in mind that if you have an HAE attack that affects your throat, you’ll self-inject Firazyr then need to get emergency medical help.

To learn about the similarities and differences between Kalbitor and Firazyr, talk with your doctor or pharmacist. You can also refer to this article.

* Kalbitor has a boxed warning for anaphylaxis. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). To learn more, see “Allergic reaction” in the “Kalbitor side effects” section above.

Are older adults able to use Kalbitor?

It’s unclear if Kalbitor is safe or effective for the acute treatment of hereditary angioedema (HAE) attacks in older adults. (“Acute” means the drug is used to treat attacks immediately.) Clinical studies of the drug didn’t include many people ages 65 years and older.

However, doctors may prescribe Kalbitor for use in this age group. But they should give it at the lowest possible dosage because older adults often have:

  • decreased liver, kidney, or heart function
  • other chronic (long-term) conditions, such as arthritis
  • more complex drug regimens than younger people

If you’re an older adult and have HAE, talk with your doctor about the best treatment plan for you.

This drug comes with several precautions.

FDA warning: Anaphylaxis

This drug has a boxed warning. This is the most serious warning from the Food and Drug Administration (FDA). A boxed warning alerts doctors and patients about drug effects that may be dangerous.

Treatment with Kalbitor may increase your risk for a serious allergic reaction called anaphylaxis. Due to this risk, you’ll receive Kalbitor injections only from a healthcare professional in a medical setting where anaphylaxis and hereditary angioedema (HAE) can be treated. The symptoms of anaphylaxis can be similar to those of HAE, so you’ll be monitored closely.

Keep in mind that if you’ve had an allergic reaction to Kalbitor in the past, you shouldn’t receive the drug again.

For more information on anaphylaxis and Kalbitor, see “Allergic reaction” in the “Kalbitor side effects” section above.

Other precautions

Before taking Kalbitor, talk with your doctor about your health history. Kalbitor may not be right for you if you have certain medical conditions or other factors affecting your health. These include:

  • Allergic reaction. If you’ve had an allergic reaction to Kalbitor or any of its ingredients, you shouldn’t have Kalbitor injections. Ask your doctor what other medications are better options for you.
  • Pregnancy. It’s not known if Kalbitor treatment is safe during pregnancy. For more information, see the “Kalbitor and pregnancy” section above.
  • Breastfeeding. It’s not known if Kalbitor treatment is safe while breastfeeding. For more information, see the “Kalbitor and breastfeeding” section above.

Note: For more information about the potential negative effects of Kalbitor, see the “Kalbitor side effects” section above.

Disclaimer: Medical News Today 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 other 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.