A Pilot Study of the Use of 129Xe and 1H MRI to Measure the Modulation of Eosinophil-Related Inflammation by Mepolizumab In COPD

Inclusion Criteria: * Diagnosis of COPD as determined by a post bronchodilator FEV1/FVC \<70% and an FEV1 of between 20 and 80% at screening visit * Treatment with inhaled triple therapy (licensed combination of long acting beta 2 agonist, long acting anti-muscarinic and corticosteroid) at constant dose for at least 12 weeks before screening visit. Treatment with roflumilast, theophyillines and macrolides will be permitted so long as they were introduced at stable dose \> 12 weeks prior to screening visit. (If maintenance drug dosing has not been with stable dosages for 12 weeks the screening visit may be rescheduled until this is achieved: see sections 7.3 and 7.10) * At least 2 acute exacerbations of COPD (AECOPD) requiring treatment with oral steroids and/or antibiotics in the last 12 months, or 1 acute AECOPD requiring hospital admission in the last 12 months. * At least one eosinophil count of \>0.3 cells·μL-1 in the 12 months prior to screening * Age over 18 years Exclusion Criteria: * Contraindication to MRI scanning, including Gadovist (ie hypersensitivity or poor renal function; see below); this includes claustrophobia and musculoskeletal difficulties, this information is collected on the UoS MRI unit screening form. * Inability to give informed consent or comply with study procedures * Hypersensitivity to mepolizumab or its excipients * Untreated helminthic infection * Exacerbation of COPD requiring treatment with oral steroids and/or antibiotics within 4 weeks o…