P94\u2005Can early changes in asthma control and quality of life predict mepolizumab response at 12 months?

Abstract

Background and objectives Mepolizumab is a monoclonal antibody approved for severe refractory eosinophilic asthma. Real-world severe asthma patients treated with mepolizumab have demonstrated a heterogeneity in response with some patients not meeting NICE criteria for oral corticosteroid (OCS) reduction after 12 months of treatment. We aim to identify early predictors of mepolizumab response. Methods We conducted a retrospective analysis of patients who received mepolizumab for 12 months at a single severe asthma clinic in the UK. Inhaler adherence was assessed using INCA devices if fractional exhaled nitric oxide (FeNO) was ≥45ppb prior to mepolizumab. Questionnaire scores including St George’s Respiratory Questionnaire (SGRQ), Asthma Control Questionnaire (ACQ)-5, full or mini-Asthma Quality of Life Questionnaire (AQLQ) and ED5Q5L-VAS, FeNO, lung function and blood eosinophil count were recorded at baseline and three months. Responders are defined as ≥50% reduction in exacerbations or maintenance OCS dose after 12 months. Results Thirty-three patients had their response assessed after 12 months of treatment. Mean reduction in maintenance OCS dose and exacerbation number were 43% and 3.4, respectively. 25 (76%) patients were responders and eight (24%) were non-responders. At three months, there was a clinically significant improvement in SGRQ (mean change -13.5±17.0, p=0.001), ACQ-5 (-0.9±1.5, p=0.004), mini-AQLQ (+1.0±1.4, p=0.007) and ED5Q5L-VAS (+7.1±15.8, p=0.021) scores. When scores were compared between responders and non-responders, mean SGRQ reductions were 16.5 and 2.5, respectively (p=0.105). Responders had a median change of 1.2 for full AQLQ score, compared to 0.2 in non-responders (p=0.061). Changes in SGRQ and full AQLQ score reached minimal clinically important differences in responders but not in non-responders. A trend towards greater improvement in FEV1 in responders was observed (+170 ml vs -140 mls, p=0.053). Percentage of predicted FEV1 improved in responders but not in non-responders (+6.5% vs -5%, p=0.033); baseline percentages did not differ significantly between the two groups (58% vs 68%, 95% CI -26.8 to 5.8, p=0.198). Conclusion In a real-world severe asthma population, changes in SGRQ, full AQLQ and FEV1 are potential early predictors of mepolizumab response. Further analyses with greater patient numbers is needed for confirmation.Abstract P94 Table 1 Change in questionnaire scores and clinical parameters after 3 months of mepolizumab Data shown as mean (SD) where parametric testing was used and median (range) where non-parametric testing was used statistically significant result are highlighted in bold. Abbreviations: SGRQ St. George’s Respiratory Questionnaire; ACQ-5, Asthma Control Questionnaire-5; AQLQ, Asthma Quality of Life Questionnaire; VAS, Visual Analogue Scale; FEV, Forced Expiratory Flow; BEC, Blood Eosinophil Count; FeNO, Fractional Exhaled Nitric Oxide.