Firazyr Icatibant Acetate Injection

1. Indications and Usage
According to the National Medical Products Administration drug registration information, the drug is indicated for the treatment of acute attacks of hereditary angioedema (HAE) in adults, adolescents, and children aged 2 years and older.
2. Dosage and Administration
Adults: The recommended dosage is 30 mg administered as a single subcutaneous injection. If the attack is not relieved or recurs, a second injection may be administered 6 hours later, and a third injection 6 hours after the second. No more than 3 doses should be given in 24 hours.
Pediatrics: The dosage is determined by weight: 12-25 kg (10 mg), 26-40 kg (15 mg), 41-50 kg (20 mg), 51-65 kg (25 mg), and >65 kg (30 mg).
Administration: The solution should be administered as a slow subcutaneous injection, preferably in the abdominal area. The injection time should be at least 30 seconds to minimize local irritation.
3. Mechanism of Action
Icatibant is a synthetic decapeptide that acts as a selective, competitive antagonist of the human bradykinin B2 receptor. Bradykinin is a potent vasodilator that mediates the swelling, inflammation, and pain characteristic of HAE. By blocking the B2 receptor, icatibant prevents bradykinin from binding and exerting its effects, thereby rapidly resolving HAE symptoms.
4. Safety and Warnings
Administration Precautions: The first injection should be administered in a healthcare setting under the supervision of a physician until the patient or caregiver is trained to perform self-injection safely.
Pregnancy and Lactation: Use is generally avoided unless clearly necessary. Animal studies show excretion in breast milk, and it is unknown if icatibant is excreted in human milk.
Renal and Hepatic Impairment: No dose adjustment is required for patients with liver or kidney damage.
5. Adverse Reactions and Clinical Research
Adverse Reactions: The most common adverse reaction is injection site reactions (including pain, erythema, pruritus, and swelling). Other reported reactions include fever, increased transaminases, dizziness, nausea, and rash.
Clinical Research: Clinical trials have demonstrated that icatibant provides rapid relief of HAE symptoms, typically within 1 to 2 hours of administration.
6. Drug Interactions
ACE Inhibitors: Concomitant use of angiotensin-converting enzyme (ACE) inhibitors may increase the risk of angioedema.
Metabolic Interactions: Icatibant is metabolized by peptidases rather than the CYP450 enzyme system, so it is not expected to have significant pharmacokinetic interactions with CYP450 substrates, inhibitors, or inducers.
7. Pharmaceutical Information
Composition: The active ingredient is icatibant acetate.
Appearance: The solution is clear and colorless to slightly yellowish.
Storage: Store in the original packaging at 2°C to 8°C. Do not freeze. Protect from light.