Icatibant

Icatibant is a synthetic 10-amino-acid peptide that blocks the bradykinin B2 receptor. Hereditary angioedema attacks are driven by bradykinin, not histamine, which is why antihistamines and adrenaline work poorly. It is a prescription medicine (Firazyr) for acute attacks in people with hereditary angioedema, self-injected subcutaneously.

1. 1

   Competitively blocks the bradykinin B2 receptor on blood vessels.

2. 2

   Stops bradykinin-driven leakage of fluid into tissue.

3. 3

   Attacks in hereditary angioedema come from uncontrolled bradykinin production when C1 inhibitor is low or faulty.

4. 4

   Relief of swelling begins within about an hour in trials.

5. 5

   Does not affect histamine pathways, so it is not useful in allergic reactions.

• Median time to first symptom relief around 2 hours in FAST-3 versus about 20 hours for placebo
• Median time to complete resolution of symptoms of roughly 8 to 10 hours
• No effect on the underlying C1 inhibitor deficiency
• Repeated doses may be needed for recurrence after about 48 hours

1. 01Lumry et al., Randomized placebo-controlled trial of the bradykinin B2 receptor antagonist icatibant for acute angioedema attacks (FAST-3), JACI 2011
2. 02European Medicines Agency - Firazyr product information

References link to published literature, regulator pages or literature indexes. Where a link points to a search, it collects the peer-reviewed work on that molecule rather than a single study.