How is omalizumab (anti-IgE antibody) administered for severe asthma or chronic spontaneous urticaria?

Administration of Omalizumab for Severe Asthma and Chronic Spontaneous Urticaria

Omalizumab is administered as a subcutaneous injection every 2-4 weeks, with dosing determined by weight and IgE levels for asthma, and as a fixed dose of 300 mg every 4 weeks for chronic spontaneous urticaria. 1

Administration Route and Preparation

• Omalizumab is administered exclusively as a subcutaneous (SC) injection 1
• Available in three formulations:
  • Prefilled syringes (75 mg/0.5 mL, 150 mg/1 mL, or 300 mg/2 mL) 1
  • Autoinjectors (same doses as prefilled syringes) 1
  • Lyophilized powder in vials (150 mg) requiring reconstitution with 1.4 mL of Sterile Water for Injection 1

Dosing for Severe Allergic Asthma

• Indicated for patients ≥12 years of age with moderate to severe persistent asthma who have a positive skin test or in vitro reactivity to a perennial aeroallergen 2
• Dosing is individualized based on:
  • Patient's body weight (kg)
  • Baseline serum total IgE level (IU/mL) measured before treatment 1
• Administered every 2 or 4 weeks according to dosing tables in the prescribing information 1
• Used as adjunctive therapy for patients requiring step 5 or 6 care (severe persistent asthma) 2

Dosing for Chronic Spontaneous Urticaria (CSU)

• Standard dose is 300 mg administered subcutaneously every 4 weeks 3, 4
• Some patients may require dosing every 2-3 weeks based on clinical response 3
• No need for IgE level testing or weight-based dosing for CSU indication 4, 5

Administration Setting and Monitoring

• Clinicians who administer omalizumab should be prepared and equipped to identify and treat anaphylaxis that may occur 2
• Patients should be observed for an appropriate period after administration due to risk of anaphylaxis 1
• The needle cap of some prefilled syringes contains a derivative of natural rubber latex which may cause allergic reactions in latex-sensitive individuals 1

Clinical Response Assessment

• For asthma: Evaluate improvement in asthma control, reduction in exacerbations, and decreased need for rescue medications 2, 6
• For CSU: Monitor response using validated tools such as the Urticaria Control Test (UCT) 3
• Response to omalizumab in CSU may be linked to baseline IgE levels and changes in IgE levels after treatment initiation 7

Special Considerations

• Omalizumab has shown efficacy for other IgE-mediated conditions beyond its approved indications, including allergic rhinitis, atopic dermatitis, and food allergies 6, 8
• Treatment discontinuation should be considered after 12-16 weeks if no clinical benefit is observed 3, 5
• Racial disparities in access to omalizumab for CSU have been documented, with White patients more likely to receive this therapy than non-White patients 2

Potential Adverse Effects

• Most common side effects include injection site reactions, viral infections, upper respiratory tract infection, sinusitis, headache, and pharyngitis 1
• Anaphylaxis is rare but can occur, requiring appropriate monitoring and emergency preparedness 2, 1