Why can't I inject it myself at home?

It carries an FDA boxed warning for anaphylaxis and must be given by a healthcare professional equipped to manage a severe allergic reaction; unlike some other HAE therapies, self-administration is not approved.

How does it stop an attack?

It inhibits plasma kallikrein, cutting the excess bradykinin that drives the swelling of an HAE attack.

How fast does it work?

In the phase 3 trials many patients had meaningful symptom improvement within the first hour to four hours after dosing.

Is it a preventive (prophylactic) treatment?

No. It is an on-demand treatment for acute attacks, not a long-term prophylactic agent.

EMA-approvedaka Kalbitor

Ecallantide — Complete Research Guide (2026)

Last updated 2026-06-30

TL;DR

Ecallantide (also known as Kalbitor) is a peptide catalogued under Therapeutic Peptides (Plasma kallikrein inhibitor). It is described as: Plasma kallikrein. Documented context: Hereditary angioedema. Neutral reference entry; EU status: EU-approved prescription medicine.

What is Ecallantide?

Ecallantide (brand name Kalbitor) is a recombinant 60-amino-acid protein that potently and selectively inhibits plasma kallikrein. It was approved by the US FDA in 2009 for the treatment of acute attacks of hereditary angioedema (HAE) in patients 12 years and older.

Evidence is strong and human, based on the phase 3 EDEMA3 and EDEMA4 randomized placebo-controlled trials.

How does Ecallantide work?

In hereditary angioedema, unchecked plasma kallikrein activity drives excess bradykinin generation, which increases vascular permeability and causes tissue swelling.

Ecallantide blocks plasma kallikrein, reducing bradykinin production and thereby limiting the acute attack.

What does the research say about Ecallantide?

Subcutaneous ecallantide significantly reduced acute HAE attack symptom severity versus placebo in the phase 3 EDEMA3 trial. ^[1]
The phase 3 EDEMA4 trial confirmed significantly greater symptom improvement at 4 hours with ecallantide compared with placebo. ^[2]
An integrated analysis of both phase 3 studies showed consistent efficacy across attack sites, including laryngeal, abdominal, and peripheral attacks. ^[3]

Clinical research & studies

The references below are the primary sources cited throughout this guide. Each links directly to PubMed or the regulator. Where evidence is preclinical (animal or in-vitro), that is stated rather than implied.

[1] Ecallantide for the treatment of acute attacks in hereditary angioedema — Cicardi M et al., The New England Journal of Medicine 2010. (Phase 3 randomized, double-blind, placebo-controlled trial (EDEMA3))
[2] EDEMA4: a phase 3, double-blind study of subcutaneous ecallantide treatment for acute attacks of hereditary angioedema — Levy RJ et al., Annals of Allergy, Asthma and Immunology 2010. (Phase 3 randomized, double-blind, placebo-controlled trial (EDEMA4))
[3] Ecallantide (DX-88) for acute hereditary angioedema attacks: integrated analysis of 2 double-blind, phase 3 studies — Sheffer AL et al., Journal of Allergy and Clinical Immunology 2011. (Integrated analysis of two phase 3 RCTs)
[4] Response time for ecallantide treatment of acute hereditary angioedema attacks — Riedl M et al., Annals of Allergy, Asthma and Immunology 2010. (Analysis of phase 3 trial data)
[5] Ecallantide: in acute hereditary angioedema — Garnock-Jones KP et al., Drugs 2010. (Drug profile / review)

Dosing context

This is not medical advice or a usage recommendation. Dosing figures are reported research context only, cited from the published literature.

In FDA labeling the studied regimen is 30 mg given as three 10 mg subcutaneous injections, with a repeat 30 mg dose possible within 24 hours if the attack persists.

This is background context only, not directions for use; administration is by a healthcare professional prepared to treat anaphylaxis.

Side effects & safety profile

Ecallantide carries an FDA boxed warning for anaphylaxis: serious hypersensitivity reactions, including anaphylaxis, have occurred, sometimes within the first hour of dosing.

Because of this risk it must be administered ONLY by a healthcare professional with appropriate medical support to manage anaphylaxis, and it should not be self-administered.

Symptoms of a hypersensitivity reaction can overlap with those of an HAE attack, so observation after dosing is required; other common adverse effects include headache, nausea, injection-site reactions, and fatigue.

Stacking & combinations

It is a single-agent acute (on-demand) treatment for HAE attacks and is not intended to be combined with other agents for performance or stacking purposes; any concurrent HAE therapy is decided by a physician.

Finding Ecallantide vendors

This is an independent, neutral directory — we sell nothing and route no purchases. Use it to read regulatory context and (where available) genuine, moderated vendor information for your country.

Choose your country

We never list placeholder vendors. Pick your country to see neutral regulatory context.

Browse the directory

User reviews

No reviews yet

Reviews appear here once submitted and moderated. An aggregate rating is shown only after at least 5 genuine reviews — we never fabricate ratings.

Frequently asked questions

It is FDA-approved to treat acute attacks of hereditary angioedema (HAE) in patients 12 years and older.

References

[1] Ecallantide for the treatment of acute attacks in hereditary angioedema — Cicardi M et al., The New England Journal of Medicine 2010. PMID: 20818887. View sourceStudy: Phase 3 randomized, double-blind, placebo-controlled trial (EDEMA3)Subcutaneous ecallantide produced significantly greater symptom improvement than placebo for acute HAE attacks.
[2] EDEMA4: a phase 3, double-blind study of subcutaneous ecallantide treatment for acute attacks of hereditary angioedema — Levy RJ et al., Annals of Allergy, Asthma and Immunology 2010. PMID: 20568386. View sourceStudy: Phase 3 randomized, double-blind, placebo-controlled trial (EDEMA4)Ecallantide significantly improved symptoms at 4 hours versus placebo with a sustained response.
[3] Ecallantide (DX-88) for acute hereditary angioedema attacks: integrated analysis of 2 double-blind, phase 3 studies — Sheffer AL et al., Journal of Allergy and Clinical Immunology 2011. PMID: 21481442. View sourceStudy: Integrated analysis of two phase 3 RCTsPooled EDEMA3 and EDEMA4 data confirmed consistent efficacy across HAE attack locations and severities.
[4] Response time for ecallantide treatment of acute hereditary angioedema attacks — Riedl M et al., Annals of Allergy, Asthma and Immunology 2010. PMID: 21130380. View sourceStudy: Analysis of phase 3 trial dataSymptomatic relief after ecallantide often began within the first hour of dosing.
[5] Ecallantide: in acute hereditary angioedema — Garnock-Jones KP et al., Drugs 2010. PMID: 20614949. View sourceStudy: Drug profile / reviewSummarizes the pharmacology, efficacy, and safety (including anaphylaxis risk) supporting ecallantide's approval.

This article is for educational and research purposes only. Peptides discussed here are not approved for human consumption by the FDA, EMA, or equivalent regulators outside of specific clinical contexts. Always consult a licensed medical professional before any therapeutic use.