Icatibant
Bradykinin B2 antagonist
Also Firazyr, Sajazir, HOE 140, HOE-140, Icatibant acetate, JE049
- Evidence
- AStrong human evidence
- FDA status
- FDA approvedas of 2026-10-26
- Route
- Injection
- Studies cited
- 1 human0 animal or cell
A self-injected drug that stops swelling attacks in people with hereditary angioedema. In 88 adults it cut the time to relief from about 20 hours to 2 hours.
Sold for
Icatibant is the on-demand injection that people with hereditary angioedema carry to stop a swelling attack.
Studies say
Placebo-controlled trials show icatibant shortens attacks from about 20 hours to about 2 hours, which supports the approval and the A grade.
Why grade A. Approval rested on three randomised phase 3 trials (FAST-1, FAST-2 and FAST-3). The cited FAST-3 trial randomised 88 patients with moderate to very severe attacks to icatibant or placebo and found median time to symptom relief of 2 hours against 20 hours. 12
FDA. Icatibant is FDA-approved as Firazyr, approved August 25, 2011, for treating acute attacks of hereditary angioedema in adults, given by subcutaneous self-injection. Generic icatibant injections have been approved since 2020. 21
Written from 2 cited sources. Fact-checked 2026-10-27: 16 claims checked, 1 corrected. Last refreshed 2026-10-27. Not physician reviewed.
What this means for you
- What people take it for
- Stopping swelling attacks from hereditary angioedema.
- Can a US doctor prescribe it?
- Yes, FDA approved for sudden swelling attacks in adults with hereditary angioedema.
- Properly tested in people?
- Yes, in large controlled trials: an 88-adult trial.
Evidence checklist
- Randomised controlled trial FAST-3 placebo-controlledyes
- Human study over 100 people FAST-3 had 88 patientsno
- More than one research group Three phase 3 trials, FAST-1 to FAST-3yes
- Clinical outcomes, not surrogate markers Time to symptom relief in attacksyes
- Human safety data beyond case reports Trial and label safety datayes
Drawn from the cited studies below. A dash means the sources give no information.
What it is
Icatibant is a lab-made peptide of ten amino acids. It blocks the bradykinin B2 receptor. Hereditary angioedema is a genetic lack of C1 esterase inhibitor. Without that brake, the body makes too much bradykinin. This peptide makes blood vessels leak. The result is sudden swelling of the skin, gut or airway. It can last days. In the throat, it can be fatal. 12
Jerini developed it, and then Shire (now Takeda). The FDA first rejected it, which led to the FAST-3 trial. It reached the US market in 2011. It comes as a prefilled syringe for injection into the abdomen. Patients are trained to give it to themselves when an attack starts. 12
How it works
Bradykinin drives the swelling in hereditary angioedema. It acts on B2 receptors on the inner lining of blood vessels. The vessels loosen their junctions and let fluid flow into tissue. Icatibant competes with bradykinin for that receptor. Bradykinin stays high, but the vessels stop responding. Icatibant does not replace the missing C1 inhibitor. It does not prevent future attacks. It treats the attack that is happening. 1
What human research shows
FAST-3 randomised 88 adults with moderate to very severe skin or abdominal attacks. They got a single subcutaneous injection of icatibant (43) or placebo (45). The median time to a 50% drop in symptom score was 2.0 hours with icatibant. With placebo it was 19.8 hours. The groups separated within the first hour. Ten patients had laryngeal attacks. Five had mild to moderate attacks and were randomised. Median time to 50% relief was 2.5 hours on icatibant and 3.2 on placebo. The other five had severe attacks and received icatibant open-label. The authors concluded that icatibant was effective and generally well tolerated. The result cleared the way for approval. 1
| Study | Model | Finding |
|---|---|---|
| FAST-3, Lumry 2011 | Humans, n=88, randomised double-blind placebo-controlled | Median time to 50% symptom relief was 2.0 hours with icatibant versus 19.8 hours with placebo. 1 |
| Firazyr label | FDA-approved prescribing information | Approved for acute attacks of hereditary angioedema in adults as a subcutaneous injection, with injection-site reactions the most common adverse event. 2 |
Safety
Almost every patient gets an injection-site reaction. These include redness, swelling, warmth, itching or pain at the site. They usually fade within hours. Other reported effects include fever, raised liver enzymes, dizziness and rash. Bradykinin also protects the heart. So the label advises caution in patients with acute ischaemic heart disease or stroke. The trials did not show a heart signal. After treating a laryngeal attack, patients are told to seek emergency care whatever the response. 12
Questions for your clinician
- How should I plan for laryngeal attacks after self-injecting?
- Do my heart conditions change whether icatibant is suitable?
- How does it compare with other hereditary angioedema treatments?
Questions people ask
Is icatibant FDA-approved?
Yes. It is sold as Firazyr and has been since August 2011. It treats acute attacks of hereditary angioedema in adults aged 18 and older. Several generic versions have been approved since 2020. 21
How fast does icatibant work?
In the FAST-3 trial, symptoms began to ease at a median of 2 hours after injection. On placebo it was about 20 hours. The difference was measurable within the first hour. 1
Does icatibant prevent attacks?
No. It blocks the bradykinin receptor during an attack. It does nothing for the C1 inhibitor deficiency underneath. Prevention uses other drugs, such as C1 inhibitor concentrate or lanadelumab. 1
Can patients inject it themselves?
Yes. It comes as a prefilled syringe for injection under the skin of the abdomen. Patients are meant to give it to themselves after training. 2
Citations
- Lumry 2011, Annals of Allergy, Asthma and Immunology: randomised placebo-controlled trial of icatibant for acute attacks of hereditary angioedema (FAST-3) doi.org
- NDC List: Firazyr (icatibant injection) label ndclist.com