What is the recommended dose and administration of icatibant (Bradykinin B2 receptor antagonist) for treating acute attacks of hereditary angioedema?

Icatibant Dosing for Acute Hereditary Angioedema Attacks

The recommended dose of icatibant for treating acute attacks of hereditary angioedema is 30 mg administered by subcutaneous injection in the abdominal area, with additional doses administered at intervals of at least 6 hours if response is inadequate or if symptoms recur, with no more than 3 doses in any 24-hour period. 1

Dosage and Administration Details

• Icatibant is supplied in a prefilled syringe delivering 30 mg (3 mL solution with a concentration of 10 mg/mL) 1
• Administer by subcutaneous injection in the abdominal area over at least 30 seconds 1
• Patients may self-administer icatibant upon recognition of symptoms of an HAE attack after proper training under healthcare professional guidance 1
• Inspect the solution visually for particulate matter and discoloration prior to administration - the drug solution should be clear and colorless 1
• Use the provided 25-gauge needle attached securely to the syringe hub 1

Treatment Response and Additional Dosing

• If response is inadequate or symptoms recur, additional doses may be administered at intervals of at least 6 hours 1
• No more than 3 doses may be administered in any 24-hour period 1
• The median time to onset of symptom relief in clinical trials was approximately 2 hours 2, 3
• In some studies, patients reported symptom improvement as early as 0.5-1 hour after administration 4, 5

Special Considerations for Laryngeal Attacks

• For laryngeal attacks, patients should be advised to seek immediate medical attention in an appropriate healthcare facility in addition to treatment with icatibant due to potential airway obstruction 1
• Clinical trials have shown that icatibant is effective for laryngeal attacks with a median time to first symptom improvement of 0.6-1.0 hours 3

Common Adverse Effects

• The most frequently reported adverse reactions are injection site reactions, occurring in almost all patients (97%) in clinical trials 1
• Injection site reactions include hematoma, burning, erythema, hypoesthesia, irritation, numbness, edema, pain, pressure sensation, pruritus, swelling, urticaria, and warmth 1
• Other common adverse reactions occurring in greater than 1% of patients include: 1
  • Pyrexia (4%)
  • Transaminase increase (4%)
  • Dizziness (3%)

Efficacy Across Attack Types

• Icatibant has demonstrated efficacy for different types of HAE attacks: 6, 2, 3
  • Cutaneous attacks
  • Abdominal attacks
  • Laryngeal attacks
• The mechanism of action as a bradykinin B2 receptor antagonist directly addresses the pathophysiology of HAE attacks 7, 5

Practical Administration Tips

• Disinfect the injection site before administration 1
• The subcutaneous route offers advantages over intravenous administration in terms of ease of self-administration 7
• Self-administration allows for earlier treatment of attacks, which has been associated with faster resolution of symptoms 7, 3

Icatibant represents a targeted approach to treating HAE attacks by antagonizing bradykinin B2 receptors, which are responsible for most symptoms of HAE 7, 5. The recommended dosing regimen provides rapid and effective relief for acute attacks while maintaining a favorable safety profile.