Xolair Omalizumab Injection

1. Indications and Usage
Moderate-to-Severe Asthma: Indicated for patients (≥12 years) with moderate-to-severe persistent allergic asthma who have an inadequate response to inhaled corticosteroids.
Chronic Spontaneous Urticaria (CSU): Indicated for adults with chronic spontaneous urticaria who remain symptomatic despite H1-antihistamine treatment.
Nasal Polyps: Indicated for inadequately controlled chronic rhinosinusitis with nasal polyps.
2. Dosage and Administration
Asthma Dosing: The dose is determined by baseline serum total IgE levels and patient weight, ranging from 75 mg to 600 mg. It is administered subcutaneously every 2 or 4 weeks.
CSU and Nasal Polyps Dosing: The recommended dose for CSU is 150 mg or 300 mg subcutaneously every 4 weeks. For nasal polyps, it is 300 mg every 4 weeks.
Administration: For subcutaneous injection only. If the calculated dose exceeds 150 mg, it must be administered as separate injections at different anatomical sites. The upper arm or thigh are preferred injection sites.
3. Mechanism of Action
IgE Binding: Omalizumab binds with high affinity to free human IgE, preventing its interaction with the high-affinity IgE receptor (FcεRI) on mast cells and basophils.
Receptor Downregulation: The binding reduces the surface expression of FcεRI on these cells, thereby inhibiting the release of inflammatory mediators (such as histamine, leukotrienes, and prostaglandins) that drive allergic responses and urticaria.
4. Safety and Warnings
Anaphylaxis: Serious, sometimes fatal, anaphylactic reactions can occur. Although most events occur after repeated doses, post-marketing surveillance has shown reactions can happen after the first dose.
Malignancies: An increased risk of malignancy has been observed in clinical trials, though a causal relationship has not been established.
Hypereosinophilic Syndrome: Cases of Churg-Strauss syndrome and other forms of hypereosinophilic syndrome have been reported.
Thromboembolism: A higher incidence of thromboembolic events has been observed in patients with nasal polyps compared to placebo.
5. Adverse Reactions and Clinical Research
Adverse Reactions: Common adverse reactions include injection site reactions, upper respiratory tract infection, headache, and viral infections.
Clinical Research: Clinical trials have demonstrated that omalizumab significantly reduces the annualized asthma exacerbation rate, improves quality of life scores, and decreases the need for oral corticosteroids. It also significantly reduces the Urticaria Activity Score in CSU patients.
6. Drug Interactions
Vaccines: No data on the effect of omalizumab on vaccines; however, clinical trials did not show an effect on the immune response to influenza vaccine. Live or live-attenuated vaccines should be avoided.
Concurrent Asthma Medications: Omalizumab is an add-on therapy and should not replace short-acting or long-acting beta-agonists and inhaled or oral corticosteroids.
7. Pharmaceutical Information
Composition: The active ingredient is omalizumab, a recombinant DNA-derived humanized monoclonal antibody.
Appearance: It is a clear to slightly opalescent, colorless to light yellow liquid.
Storage: Store at 2°C to 8°C (refrigerate). Do not freeze or shake. Protect from light.