Omalizumab

Indications

Asthma: Omalizumab is indicated for patients 6 years of age and older with moderate to severe persistent asthma who have a positive skin test or in vitro reactivity to a perennial aeroallergen and whose symptoms are inadequately controlled with inhaled corticosteroids. Omalizumab has been shown to decrease the incidence of asthma exacerbations in these patients.

Chronic Idiopathic Urticaria (CIU): Omalizumab is indicated for the treatment of adults and adolescents 12 years of age and older with chronic idiopathic urticaria who remain symptomatic despite H1 antihistamine treatment.

Pharmacology

Asthma: Omalizumab inhibits the binding of IgE to the high-affinity IgE receptor (FcεRI) on the surface of mast cells and basophils. Reduction in surface-bound IgE on FcεRI-bearing cells limits the degree of release of mediators of the allergic response. Treatment with Omalizumab also reduces the number of FcεRI receptors on basophils in atopic patients.

Chronic Idiopathic Urticaria: Omalizumab binds to IgE and lowers free IgE levels. Subsequently, IgE receptors (FcεRI) on cells down-regulate. The mechanism by which these effects of omalizumab result in an improvement of CIU symptoms is unknown.

Dosage And Administration

Subcutaneous-

Poorly controlled, moderate to severe asthma:

  • Adult: Doses (mg) and dosing frequency are based on pre-treatment serum IgE levels (IU/mL) and body wt (kg) as follows: ≥30-100 IU/mL: 150 mg (30-90 kg); 300 mg (>90-150 kg). >100-200 IU/mL: 300 mg (30-90 kg). >200-300 IU/mL: 300 mg (30-60 kg). All doses to be taken every 4 wk. >100-200 IU/mL: 225 mg (>90-150 kg). >200-300 IU/mL: 225 mg (>60-90 kg); 300 mg (>90-150 kg). >300-400 IU/mL: 225 mg (30-70 kg); 300 mg (>70-90 kg). >400-500 IU/mL: 300 mg (30-70 kg); 375 mg (>70-90 kg). >500-600 IU/mL: 300 mg (30-60 kg); 375 mg (>60-70 kg). 375 mg (30-60 kg). All doses to be taken every 2 wk. Doses no more than 150 mg should be admin at 1 inj site.
  • Child: ≥12 yr Same as adult dose.

Chronic idiopathic urticaria:

  • Adult: 150 or 300 mg every 4 wk.
  • Child: ≥12 yr Same as adult dose.

Contraindications

Severe hypersensitivity reaction to Omalizumab or any ingredient of this preparation

Side Effects

Generalised pain, arthralgia, myalgia, fatigue, dizziness, earache, headache, GI disturbances, fractures, pruritus, alopecia, dermatitis, upper resp tract infections, viral infections, sinusitis, pharyngitis, flu-like illness, systemic eosinophilia (e.g. Churg-Strauss syndrome).

Pregnancy And Lactation

Pregnancy Category B. Either animal-reproduction studies have not demonstrated a foetal risk but there are no controlled studies in pregnant women or animal-reproduction studies have shown an adverse effect (other than a decrease in fertility) that was not confirmed in controlled studies in women in the 1st trimester (and there is no evidence of a risk in later trimesters).

Precautions And Warnings

Not intended for treatment of acute asthma exacerbations, acute bronchospasm or status asthmaticus. Patient at risk of parasitic infections. May increase risk of malignancy. Delayed onset of anaphylaxis, it usually occurs 2 hr after admin but may also occur up to 4 days to >1 yr after initiation of regular treatment. Avoid abrupt withdrawal of corticosteroid therapy. Renal and hepatic impairment. Childn. Pregnancy and lactation.

Overdose Effects

The maximum tolerated dose of Omalizumab has not been determined. Single intravenous doses of up to 4,000 mg have been administered to patients without evidence of dose limiting toxicities. The highest cumulative dose administered to patients was 44,000 mg over a 20 week period, which was not associated with toxicities.

Therapeutic Class

Antihistamines anti-allergies & hypo-sensitisation.

Storage Conditions

Store between 2-8°C. May be transferred at room temp. Do not freeze. Following reconstitution, protect from direct sunlight. Stable for up to 8 hr if refrigerated or 4 hr if at room temp.