Skin & aging Bradykinin B2 antagonist
Icatibant
Regulatory status
Status at a glance
503A compounding status
Not nominated
We found no pending nomination for the 503A bulks list. Unless the substance has another legal pathway (for example, a USP monograph or use in an FDA-approved drug), 503A pharmacies generally may not compound with it.
- FDA approval
- An FDA-approved product contains this peptide
- 503B outsourcing
- Not determined
- Anti-doping (WADA)
- Not on the WADA Prohibited List
- DEA schedule
- Not a controlled substance
About peptide status
Most peptides discussed here are not FDA-approved for any use, and products labeled “research use only” are not for human use. Removal from Category 2 does not authorize compounding. PCAC votes are non-binding recommendations; FDA and HHS make the final decisions.
This is not medical or legal advice, and we do not publish dosing, sourcing or reconstitution information. Talk with a licensed clinician before using any peptide.
If you think you are having a medical emergency, call 911.
Key takeaway
Icatibant (sold as Firazyr) is a peptide that blocks the bradykinin B2 receptor, used to treat acute attacks of hereditary angioedema, a condition of sudden, severe swelling. By blocking the mediator that drives the swelling, it shortens attacks. It has been FDA-approved in the U.S. since 2011 and can be self-administered as a subcutaneous injection.
At a glance
- What it is
- A bradykinin B2 receptor antagonist peptide
- Approved for
- Acute attacks of hereditary angioedema in adults
- Key fact
- In the FAST-3 trial it cut the time to meaningful symptom relief from about 20 hours to 2 hours versus placebo
- Route
- Subcutaneous injection, self-administered into the abdomen
- Evidence strength
- FDA approved
Summary
Icatibant is an FDA-approved peptide that blocks the bradykinin B2 receptor in hereditary angioedema attacks. Learn how it works and its side effects.
What is icatibant?
Icatibant, sold under the brand Firazyr, is a synthetic ten-amino-acid peptide that blocks the bradykinin B2 receptor. It is used for acute attacks of hereditary angioedema (HAE), a genetic disorder in which episodes of severe swelling affect the skin, abdomen, and sometimes the airway. It was developed under the code HOE 140 and approved in the United States in 2011.
How does icatibant work?
Icatibant targets bradykinin, the molecule responsible for the swelling in hereditary angioedema. In HAE, a deficiency or dysfunction of the C1 inhibitor protein leads to overproduction of bradykinin, which binds B2 receptors on blood vessels and makes them dilate and leak fluid into tissues, producing the characteristic swelling and pain. Icatibant is a selective competitive antagonist at the B2 receptor, so it blocks bradykinin from acting there and allows the attack to subside.
Because it acts directly at the receptor regardless of the upstream cause, it works in HAE attacks driven by bradykinin and can be given by the patient at the first sign of an attack. In the FAST-3 trial, icatibant shortened the median time to meaningful symptom relief to about 2 hours, compared with roughly 20 hours on placebo.
Is it FDA-approved?
Editor’s note
Status: Yes. Icatibant was approved by the FDA in 2011 for acute attacks of hereditary angioedema in adults, and generic versions are also available. It is formulated for subcutaneous self-injection.
Category: FDA-approved · Primary body area: Skin & aging
Yes. Icatibant was approved by the FDA in 2011 for acute attacks of hereditary angioedema in adults, and generic versions are also available. It is formulated for subcutaneous self-injection.
What is icatibant prescribed for?
Icatibant is prescribed to treat acute attacks of hereditary angioedema in adults. Patients are typically trained to self-inject at the onset of an attack. Attacks involving the airway still warrant medical attention, even after treatment.
What are the side effects?
According to the prescribing information, common side effects include:
- Injection-site reactions such as redness, swelling, pain, and itching, which are nearly universal
- Fever
- Dizziness
More serious considerations include:
- Potential for delayed airway symptoms in laryngeal attacks, which should be monitored in a medical setting
- Hives, reported after approval
Sources: FDA prescribing information for Firazyr; the FAST-3 trial (Lumry et al., Annals of Allergy, Asthma & Immunology, 2011, DOI: 10.1016/j.anai.2011.08.015), indexed on PubMed. This document is educational and does not constitute medical advice.
Registered human trials
0 registered human trials on ClinicalTrials.gov that we reviewed
Sources
- [1]
- [2]
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