TY - JOUR T1 - BTS Difficult Asthma Registry: Effect of omalizumab dosing table expansion on size of population of severe persistent allergic asthma patients potentially eligible for omalizumab therapy JF - European Respiratory Journal JO - Eur Respir J VL - 40 IS - Suppl 56 SP - 4699 AU - Liam Heaney AU - Andrew Menzies-Gow AU - Adel Mansur AU - Chris Brightling AU - Robert Niven AU - Rekha Chaudhuri AU - Christine Bucknall AU - Amr Radwan Y1 - 2012/09/01 UR - http://erj.ersjournals.com/content/40/Suppl_56/4699.abstract N2 - The dosing of omalizumab is determined by baseline serum total IgE and body weight. In 2010, the EU licence for omalizumab increased the maximum baseline total IgE in the dosing table from ≤700 IU/mL ('Standard' dose) to >700–1500 IU/mL ('Expanded' dose). Using data from the BTS Difficult Asthma Registry we evaluated the effect of this expansion on the size of the patient population with severe persistent allergic asthma potentially eligible for omalizumab therapy. 582 adult and adolescent patients were identified from all seven Specialist Centres that submit data to the Registry. Mean age was 21.4 (±18.6) years and mean IgE was 501 (±1546) IU/mL. With the expansion of the dosing table, the percentage increase in the pool of patients with severe persistent allergic asthma potentially eligible for omalizumab was less than 23%, when applying the omalizumab licence criteria (Population A). With the addition of the NICE criteria (Population B) an even smaller percentage increase in the patient pool was seen [Figure]. In conclusion, despite the expansion in license and application of NICE criteria, the change in the number of patients eligible for omalizumab treatment is relatively modest.BTS=British Thoracic Society; SPT=skin-prick test; RAST=radioallergosorbent test; ICS=inhaled corticosteroid; LABA=long-acting β2-agonist. ER -