Patients and Selection Process
Twenty-four allergic and non-allergic adult subjects aged 18-75 with severe bilateral nasal polyps (average bilateral endoscopic nasal polyp total score of at least 5 out of 8 as defined below), eosinophil count of 300/µl or greater, refractory symptoms despite prior surgical polypectomy, and at least one oral steroid course over the previous twelve months were recruited. Potential subjects were excluded if they received immunosuppression or allergen immunotherapy build up in the past 3 months. Pregnant patients, those with cancer, immune deficiency, or helminth infection were also excluded as well as those receiving any type of anti-interleukin therapy. The study was performed at the Johns Hopkins University Asthma and Allergy Centre and was approved by the Johns Hopkins IRB. All participants provided written consent.