4-month omalizumab efficacy outcomes for severe allergic asthma: the Dutch National Omalizumab in Asthma Registry

Omalizumab is licensed as add-on therapy for patients with severe allergic asthma. Response is in most studies scored by the physician's global evaluation of treatment effectiveness (GETE). A good clinical and validated parameter for treatment response is currently missing. Also, there are no established criteria for identifying patients who will respond to omalizumab based on pre-treatment characteristics. The Dutch National Omalizumab in Asthma Registry was developed in 2011 to better evaluate inclusion criteria and measure treatment response after 4 months. This is a "real world" prospectively designed, observational data registry in which the outcomes of patients who received omalizumab between 2012 and 2015 were evaluated. Data were collected from all centers in the Netherlands comprising demographic features, criteria for starting treatment, GETE, FEV1, oral corticosteroid use and ACQ. 65.5% of the 403 patients had a good or excellent response to omalizumab after 16 weeks according to the treating physician GETE. 64.5% fulfilled all the criteria for prescribing omalizumab at baseline. The mean ACQ improved from 2.96 at baseline to 1.83 at 16 weeks (p