Omalizumab is effective for severe, “difficult-to-treat” allergic asthma in patients above 12 years of age.
It is a recombinant humanised monoclonal IgG1 antibody that binds to IgE to inhibit the initiation of the allergic cascade. Omalizumab reduces the frequency of asthma exacerbations, and the need for inhaled corticosteroids and bronchodilators; and improves the forced expiratory volume, symptoms, and quality of life.
The Thoracic Society of Australia and New Zealand set guidelines for it’s use, and strict criteria control the PBS authority supply of this expensive drug to patients (of respiratory specialists) who achieve predetermined response criteria.
Anaphylaxis occurs unpredictably in 0.1 – 0.2% of patients and may be delayed by up to 24 hours. Management of anaphylaxis must be considered for those in remote areas. Injection site reactions and headache are the most common adverse reactions, but there is also an uncertain risk of an increase in malignancies.
Medicare statistics show hospital outpatients supplies at $142,378 in August 2012, implying that fewer than 80 people in Australia are using omalizumab (average dose of 4 vials per month2). With asthma affecting around 10% of Australians, and as the underlying cause in 0.2% of all deaths, these numbers show just how severely affected a patient should be before the benefits from omalizumab become cost effective.
- eTG complete [CD-ROM]. Melbourne: Therapeutic Guidelines Limited; 2012 Jul.
- Thoracic Society of Australia and New Zealand. Omalizumab: recommendations for use in the Australasian context, April 2009. (A consensus paper of The Thoracic Society of Australia and New Zealand); 2009.
- National Institute of Clinical Excellence, UK. Omalizumab for severe persistent allergic asthma. November 2007, Reviewed 2010.