Acute attacks
Sudden attacks of hereditary angioedema.
Clinical trials
Studies that evaluate the effectiveness and safety of medications or medical devices before they are approved for use by the general public.
Ecallantide (e-KAL-lan-tide)
A protein made in yeast cells; ecallantide is the active ingredient in KALBITOR (ecallantide).
Abbreviation for hereditary angioedema.
Hereditary Angioedema
A rare, hereditary disease of the immune system that causes attacks of sudden swelling in various parts of the body.
KALBITOR Home Infusion Services®
KALBITOR Home Infusion Services is a program in which an experienced infusion nurse will administer your subcutaneous KALBITOR treatment in the comfort of your own home. This professional service is available to HAE patients, 12 years of age or older, who use KALBITOR to treat their sudden HAE attacks on demand. KALBITOR Home Infusion Services is not appropriate for treating laryngeal attacks.
KALBITOR® (KAL-bit-or)
A prescription medicine used to treat sudden attacks of hereditary angioedema in patients 12 years of age and older. KALBITOR® is not a cure for HAE.
Laryngeal attack
An HAE attack that affects the larynx (throat); this can block or close the airway, leading to difficulty breathing and, potentially, death.
The part of the throat that contains the vocal cords and is used for breathing, swallowing, and talking.
On-demand treatment
On-demand HAE treatment is used to treat sudden attacks of HAE as they occur, in order to relieve symptoms associated with the attack. On-demand treatment is not used to prevent attacks from occurring.
PATHWAYS 360 is a program that provides comprehensive, personalized support services to hereditary angioedema patients. Each patient works with a program case manager who guides the patient through their entire treatment journey with KALBITOR® (ecallantide), including health insurance support, financial assistance, treatment location coordination, and much more.
Plasma kallikrein (kal'i-kre'in)
A protein in the body that triggers the release of a substance that may lead to hereditary angioedema attack symptoms.
Under the skin.
In hereditary angioedema, something that causes an attack.
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HAE is a Serious Disease

Hereditary angioedema (HAE) attacks are unpredictable and can be potentially life-threatening. Help your patients better manage their condition by better understanding the source of acute HAE attacks.

Please see Full Prescribing Information, including Boxed Warning and Medication Guide.

About HAE

Hereditary angioedema (HAE) is characterized by unpredictable episodes of swelling.1

  • Clinical presentation of HAE attacks can vary widely, occurring at highly variable frequencies—in some patients on a weekly basis and in others only once or twice a year.2
  • Subcutaneous and submucosal swelling typically develops over 12 to 36 hours, and gradually subsides over 2 to 5 days.2
  • Attack triggers are often unidentified, but may include stress, minor trauma (such as dental procedures), menstruation and pregnancy, some drugs such as oral contraceptives, or infection.3

HAE attacks typically occur in one or more of these three main sites:4

  • Abdominal organs such as the GI tract
  • Larynx
  • Periphery, including the face, hands, feet and genitals

Warning Signs 5,6,7

Many patients experience warning signs before an HAE attack including:

  • Sudden mood changes, anxiety, or complete exhaustion
  • A tingling sensation in the soon-to-be-affected area
  • A painless, non-itchy rash, which may migrate from one location to another

KALBITOR® (ecallantide) is the first subcutaneous treatment approved for acute attacks of hereditary angioedema in patients 12 years of age and older.8

1 Bork K, Meng G, Staubach P, Hardt J. Hereditary angioedema: new findings concerning symptoms, affected organs, and course. Am J Med. 2006;119:267-274.
2 Gompels M, Lock R, Abinum M, et al. C1 inhibitor deficiency: consensus document. Clin and Exp Immunol. 2005;139:379-394.
3 Bowen T, Cicardi M, Bork K, et al. Hereditary angioedema: a current state-of-the-art review, VII: Canadian Hungarian 2007 international consensus algorithm for the diagnosis, therapy, and management of hereditary angioedema. Ann Allergy Asthma Immunol. 2008;100:S30-S40.
4 Agostoni A, Cicardi M. Hereditary and acquired C1-inhibitor deficiency: biological and clinical characteristics in 235 patients. Med. 1992;71:206-215.
5 Agostoni A, Aygoren-Pursun E, Binkley KE, et al. Hereditary and acquired angioedema: Problems and progress: Proceedings of the third C1 esterase inhibitor deficiency workshop and beyond. J Allergy Clin Immunol. 2004;114(3 Suppl): S51-131.
6 Weis M. Clinical review of hereditary angioedema: Diagnosis and management. Postgrad Med. 2009; 121: 113-120.
7 Zuraw BL. Hereditary angioedema. N Eng J Med. 2008;359:1027-1036.
8 KALBITOR® (ecallantide) Full Prescribing Information, Dyax Corp., Burlington, Massachusetts, March 2015.

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Important Safety
Information for KALBITOR.


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Learn how PATHWAYS 360® can help you prepare a treatment plan for your patient’s next acute HAE attack.

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KALBITOR® (ecallantide) is a plasma kallikrein inhibitor indicated for treatment of acute attacks of hereditary angioedema (HAE) in patients 12 years of age and older.
Important Safety Information

WARNING: Anaphylaxis

  • Anaphylaxis has been reported after administration of KALBITOR.
  • Because of the risk of anaphylaxis, KALBITOR should only be administered by a healthcare professional with appropriate medical support to manage anaphylaxis and HAE.
  • Healthcare professionals should be aware of the similarity of symptoms between hypersensitivity reactions and HAE and patients should be monitored closely.
  • Do not administer KALBITOR to patients with known clinical hypersensitivity to KALBITOR.


Do not administer KALBITOR to a patient who has known clinical hypersensitivity to KALBITOR.


In 255 HAE patients treated with intravenous or subcutaneous KALBITOR in clinical trials, 10 patients (4%) experienced anaphylaxis. For the subgroup of 187 patients treated with subcutaneous KALBITOR, 5 patients (3%) experienced anaphylaxis. These reactions occurred within the first hour after dosing.

Symptoms associated with these reactions have included chest discomfort, flushing, pharyngeal edema, pruritus, rhinorrhea, sneezing, nasal congestion, throat irritation, urticaria, wheezing, and hypotension.

Patients should be observed for an appropriate period of time after administration of KALBITOR, taking into account the time to onset of anaphylaxis seen in clinical trials. Given the similarity in hypersensitivity symptoms and acute HAE symptoms, patients should be monitored closely in the event of a hypersensitivity reaction.


The most common adverse events (≥3% and greater than placebo) in HAE patients were headache, nausea, diarrhea, pyrexia, injection site reactions, and nasopharyngitis.

There is a potential for immunogenicity with the use of KALBITOR. Overall, 20.2% of patients seroconverted to anti-ecallantide antibodies. Anti-ecallantide IgE antibodies were detected at a rate of 4.7% for tested patients, and anti-P. pastoris IgE antibodies were also detected at a rate of 20.2%. Patients who seroconvert may be at a higher risk of a hypersensitivity reaction. The long-term effects of antibodies to KALBITOR are not known.


KALBITOR should only be administered by a healthcare professional with appropriate medical support to manage anaphylaxis and hereditary angioedema. Safety and effectiveness of KALBITOR in patients below 12 years of age have not been established.

Please see the Full Prescribing Information, including Boxed Warning and Medication Guide.

Healthcare professionals should report all suspected adverse events associated with the use of KALBITOR. Please contact Dyax Corp. at 1-888-452-5248. Alternatively, this information may be reported to the FDA MedWatch System by phone at 1-800-FDA-1088, or by mail using Form 3500 at