What is Omalizumab?
It is a recombinant,humanized IgG1 monoclonal antibody that binds the IgE molecule at the same epitope on the Fc region that IgE binds the FcE RI receptor on the mast cells or basophils.
Mechanism of action
Ig E plays a central role in initiating bronchial asthma, by binding the allergen to specific receptors on mast cells to cause it degranulate. Omalizumab binds with the Fc portion of allergen laden IgE molecules and prevent it from binding to Fc receptor.
Projected indications
1. Asthma for atleast 1 year and on inhaled corticosteroids.
2. At least one positive allergen skin test.
3. Elevated IgE levels.
4. Patient with persistant asthma with coexistant allergic rhinitis, sinusitis and gastroesophageal disease.
Dasage: 0.016mg/kg wt/iu of IgE every 4 weeks subcutaneously. (aim is to reduce IgE <10 iu/ml)
Adverse effects
1.Epithelial and solid organ malignancies.
2. Anaphylaxis (paradoxical)
3.Rash,diarrhoea,vomiting,Epistaxis,menorrhagia, hematoma in injection sites.
