A study into efficacy of omalizumab therapy in patients with severe persistent allergic asthma at a tertiary referral centre for asthma in Ireland

Abstract

Background: Asthma is a chronic airway disease characterized by airway inflammation, bronchial hyperresponsiveness and airflow obstruction. Patients with persistent symptoms despite maximum standard treatment as per Global Initiative of Asthma guidelines are considered to have severe persistent asthma. Omalizumab is a recombinant humanized monoclonal antibody licenced for use as an add-on therapy in these patients.

Aim: To assess the clinical benefit amongst responders to omalizumab therapy at a tertiary referral centre.

Methods: This was a retrospective audit assessing the effect of omalizumab therapy on asthma control, frequency of exacerbation and hospitalization rates over 6 months before and after therapy.

Results: The study included 30 responders (14 females). There was a reduction in exacerbation and hospitalization rates following initiation of omalizumab, 73 and 91%, respectively (P-value < 0.0001). The number of exacerbations decreased from 3.48 ± 2.20 to 0.93 ± 0.83 and the mean number of admissions decreased from 1.07 ± 1.1 to 0.1 ± 0.40 over the study duration (P < 0.001). There was 73% reduction in the weekly need for rescue salbutamol therapy with mean of 30.33 ± 6.49 puffs to 8.23 ± 1.51 puffs after omalizumab therapy (P < 0.0001). Seventy-nine per cent of patients were able to reduce their maintenance oral corticosteroid therapy.

Conclusion: Overall, responders to omalizumab therapy are less likely to experience an asthma exacerbation and hospitalization. They were also more likely to reduce maintenance corticosteroid therapy and the need for rescue reliever therapy. These data suggest that omalizumab has proven effective in improving health outcomes for a cohort of carefully selected patients with severe allergic asthma in Ireland.