Mepolizumab has been approved for treatment in severe eosinophilic asthma. However, there are no post-approval practice-based data on its effectiveness and safety.
We performed a retrospective chart review of patients who received mepolizumab for asthma and compared characteristics from 6 months prior to starting mepolizumab to 6 months after starting. Characteristics analyzed included demographics, history, asthma severity and eosinophil counts.
We recruited twenty-four patients who received at least 6 months of continuous mepolizumab. Mean age was 51.0±10.4 years and 17/24 (71%) were female. 19/24 (79%) had history of chronic rhinosinusitis (CRS), 14 of whom had nasal polyps. Immediately prior to starting mepolizumab, patients required a mean of 2.3±0.9 controller medications. 7/24 (29%) previously received omalizumab. After starting mepolizumab, eosinophil counts decreased by >90% (1.2±1.1 vs 0.11±0.10/mm3, p=0.0001). Total asthma exacerbations in 6 months decreased by >55% (2.2±1.8 vs 0.9±1.4, p=0.0006) and number of steroid courses in 6 months decreased by >60% (2.3±1.8 vs 0.9±1.2, p=0.0003). There was a small improvement in FEV1 (1.8±1.0 vs 1.9±1.0 liters, p=0.025). The 10 patients who began mepolizumab while on chronic daily prednisone significantly reduced their daily prednisone dosage (9.4±3.6 mg vs 4.0±4.0 mg, p=0.024). Based on overall global physician assessment, 22/24 (92%) had improvement in asthma control and 7/16 (44%) had improvement in CRS. A 36-year-old patient developed shingles, and 5 complained of new-onset fatigue.
Real-world treatment of eosinophilic asthma with mepolizumab was associated with reduced oral steroid use and improvement in lung function, disease control, and fewer asthma exacerbations with minimal adverse effects.