Patient population
Adult patients (>18 years) diagnosed with eCRS who had
undergone endoscopic sinus surgery and whose upper airway disease was
not controlled with long term continuous oral corticosteroids were
eligible for participation. Exclusion criteria included patients
previously treated with mepolizumab, mepolizumab hypersensitivity,
established immunodeficiency, cystic fibrosis, pregnancy, lactation and
hypereosinophilic syndromes.
Patients were recruited to receive 100mg subcutaneous mepolizumab
(GlaxoSmithKline, UK) at four-weekly intervals for 24 weeks. Demographic
characteristics, including age, gender, asthma status, atopy, smoking
status, date of previous surgery, and use of intranasal and systemic
corticosteroid medication, were recorded. Asthma status was determined
by either a 15 percent change in forced expiratory volume in 1 second on
spirometry with challenge testing or β-agonist use, or current use of
regular inhaled bronchodilator or corticosteroid therapy. Atopy was
determined by an spIgE automated immunoassay (ImmunoCAPVR, Thermo Fisher
Scientific, Massachusetts, United States). Concentration of any allergen
group >0.35 kUA/L was classed as a positive result. The
grass mix consisted of Lolium perenne , Phleum pratense ,Poa pratensis (Kentucky blue), Sorghum halepense(Johnson), Paspalum notatum (Bahia) and Cynodon dactylon(Bermuda). The dust mite mix contained Dermatophagoides
pteronyssinus , Dermatophagoides farina and Blatella
germanica (German cockroach). The mould mix comprised Penicillium
chrysogenum , Cladosporium herbarum , Aspergillus fumigatusand Alternaria alternata . The animal epithelium mix includedFelis domesticus (Cat), Equus caballus (Horse), Bos
Taurus (Cow) and Canis familiaris (Dog). Smoking status was
defined by having smoked within the last 12 months. Medication name and
dosage were recorded at screening and reviewed at each treatment visit.
All trial participants were precluded from changing medication in the
four weeks prior to commencement of mepolizumab treatment.