Short- and long-term real-world effectiveness of omalizumab in severe allergic asthma: systematic review of 42 studies published 2008-2018

<b>Introduction</b>: Omalizumab is a recombinant monoclonal anti-IgE antibody approved in the US as add-on treatment in moderate-to-severe allergic asthma (in severe allergic asthma [SAA] in Europe). A 2016 review of 24 real-world effectiveness studies in SAA published between 2008–2015 concluded that omalizumab was associated with significant improvements in objective and subjective outcomes with benefits extending beyond 2 years. Several new real-world studies have been published since, bringing the total to 42 studies. <b>Areas covered</b>: This systematic review of 42 studies published since 2008 updates and extends the 2016 review on the real-word evidence on omalizumab in SAA. It offers greater granularity as to time windows within which outcomes are reported and includes studies extending well beyond 4 years post omalizumab initiation. <b>Expert commentary</b>: This review firmly establishes the short-term effectiveness of omalizumab in adolescent and adult patients with SAA at 1 year, and provides strong evidence of long-term effectiveness up to 4 years and emergent evidence of effectiveness beyond 4 years. In the aggregate, these 42 studies underscore the long-term effectiveness of omalizumab in terms of: reducing exacerbations and symptoms, achieving asthma control, improving lung function, enhancing quality of life, decreasing emergency department visits and hospitalizations, and promoting concomitant medication-sparing.