The effects of lebrikizumab in patients with mild asthma following whole lung allergen challenge

BackgroundInterleukin 13 (IL13) is a T-helper type 2 (Th2) cytokine associated with inflammation and pathology in allergic diseases such as bronchial asthma. We have shown that treatment with lebrikizumab, an anti-IL13 monoclonal antibody, significantly improves prebronchodilator forced expiratory volume in 1s (FEV1) in a subset of subjects with uncontrolled asthma. ObjectiveTo evaluate efficacy and safety of lebrikizumab in subjects with mild asthma who underwent bronchial allergen challenge. MethodsTwenty-nine subjects were randomized 1:1-5mg/kg lebrikizumab (n=13) or placebo (n=16) administered subcutaneously every 4weeks over 12weeks, a total of four doses. Primary efficacy outcome was late asthmatic response (LAR) at Week 13, defined as area under the curve of FEV1 measured 2-8h following inhaled allergen challenge. Serum biomarkers were measured to verify IL13 pathway inhibition and identify patients with an increased response to lebrikizumab. ResultsAt Week 13, the LAR in lebrikizumab subjects was reduced by 48% compared with placebo subjects, although this was not statistically significant (95% confidence interval, -19%, 90%). Exploratory analysis indicated that lebrikizumab-treated subjects with elevated baseline levels of peripheral blood eosinophils, serum IgE, or periostin exhibited a greater reduction in LAR compared with subjects with lower baseline levels of these biomarkers. Lebrikizumab exerted systemic effects on markers of Th2 inflammation, reducing serum immunoglobulin E (IgE), chemokine ligands 13 and 17 by approximately 25% (P<0.01). Lebrikizumab was well tolerated. Conclusion and Clinical RelevanceLebrikizumab reduced the LAR in subjects with mild asthma. Clinical trial number NCT00781443.