P134 Real world experience of mepolizumab in steroid-dependent severe eosinophilic asthma: one year outcomes. (December 2018) - Kavanagh, JE
Abstract : Introduction: Mepolizumab is a monoclonal antibody against IL-5 and is licensed for treatment of severe eosinophilic asthma (SEA). In clinical trials, most patients dependent on maintenance oral prednisolone (mOCS) were able to reduce or stop mOCS by 24 weeks. At present, real world data on the steroid-sparing effect of mepolizumab after a year of treatment are lacking. Method: We carried out a retrospective review of patients in a tertiary asthma centre with SEA who required mOCS in addition to high dose inhaled corticosteroid/long-acting ß2 agonists and had completed 12 months of mepolizumab treatment (100 mg SC, 4-weekly). mOCS dose, blood eosinophil count, post-bronchodilator FEV1, fractional exhaled nitric oxide (FeNO), Asthma Control Questionnaire (ACQ6), Mini Asthma Quality of Life Questionnaire (mini-AQLQ) and exacerbation history were documented at baseline and one year. At one year patients reported any side effects, and their own view of treatment efficacy (5-point Likert scale). Results: Fifty-two patients were included in the analysis (59.6% female, mean age 52.9±12.4, BMI 30.7±5.62). The median mOCS dose reduced from 10 mg (IQR 10–15) at baseline to 1 mg (IQR 0–10) at 1 year (p≤0.001). ACQ6 score fell from a mean of 2.88 (±1.25) to 2.12 (±1.31; Δ0.76; p=0.005) and mini-AQLQ rose from a baseline of 3.78 (±1.42) to 4.65 (±1.65; Δ0.87; p<0.001). There was no significant change in FeNO or FEV1. Median exacerbation rate was unchanged (2, IQR 0–3). Most patients reported their asthma was 'much better' controlled (55.8%) or 'somewhat better' controlled (17.3%) since commencing mepolizumab. No patients reported worsening control. 19.2% reported side effects, however no patient discontinued the drug on this account. Six patients (11.5%) stopped treatment early due to lack of response. Conclusion: Mepolizumab enabled a significant reduction (≥50%) in mOCS dose in 38 patients (73.1%) with a simultaneous improvement in asthma control and quality of life scores, of an order that is both clinically and statistically significant. This compares favourably to the trial data at 24 weeks. Why a significant minority did not benefit from mepolizumab treatment despite an eosinophilic phenotype requires further investigation.