Mepolizumab Use in Patients with Severe Eosinophilic Asthma: Real-World Experience

In one practitioner's experience, adding mepolizumab (Nucala, GlaxoSmithKline) to the treatment regimens of patients with severe eosinophilic asthma in his practice resulted in improved symptoms and quality of life, similar to those reported in controlled clinical trials with screened participants.

"After extensive double-blind controlled studies, it is always reassuring to the physician in the field that the results of these studies are applicable in a private practice office setting," Ronald Strauss, MD, Cleveland Allergy & Asthma Center and Case Western Reserve University Medical School, Cleveland, Ohio, told MD Magazine®.

For the case-series report, Strauss retrospectively reviewed the records of 18 men and 18 women in his practice who received monthly subcutaneous injections of mepolizumab as an add-on treatment for asthma for 6 to 14 months, (mean duration, 10 months). Each patient served as their own control; with symptoms by history, pulmonary function tests, and response on the asthma control questionnaire (ACQ) in the corresponding period before the injection then compared with symptoms during treatment.

The patients ranged in age from 36 to 92 years (mean age, 58 years). The duration of asthma symptoms ranged from 2 to 61 years (mean duration, 33 years). Thirty-one of the patients (86%) had allergic rhinitis, and 6 were receiving immunotherapy for their allergies. Eight patients had a history of smoking and 3 were currently smoking less than one-half pack per day. Eleven patients were obese and 5 were morbidly obese, with body mass index (BMI) greater than 40. Each patient had an eosinophil count of at least 150 cell/µL, (range, 150 to 1700; mean, 404 cell/µL).

In the year prior to receiving mepolizumab, all patients had at least 2 symptom exacerbations that required treatment with short bursts of high-dose prednisone. All required ongoing, high daily doses of an inhaled corticosteroid with a long-acting beta-adrenergic agonist, montelukast, and as-needed controller medications, including terbutaline injections.

Strauss reported that there were 124 exacerbations in the period of 6 to 14 months before treatment, which was reduced to 25 in the corresponding period with monthly mepolizumab injections. In addition, there had been 3.2 bursts of high-dose prednisone required before mepolizumab, compared to 0.7 in the period after mepolizumab was started. Seven of the 13 steroid-dependent asthmatics were able to discontinue prednisone after an average of 6 months on mepolizumab (range, 1 to 12 months).

The ACQ scores prior to the addition of mepolizumab ranged from 0.28 to 4.0 (mean, 1.69). After adding mepolizumab, the ACQ score ranged from 0 to 2.57 (mean, 0.93). The frequency of cough, wheeze, dyspnea at rest, and exercise-induced asthma were also reported to be significantly decreased with mepolizumab, as was the use of rescue inhalers.

“[The patients] frequently reported feeling significantly better with increased quality of life and had increased energy,” wrote Strauss and colleague Nesreen Jawhari, MN. “Although the frequency of upper respiratory infections appeared to be about the same, they did not precipitate exacerbations as frequently as before being treated with mepolizumab, thus frequently obviating the need for bursts of prednisone.”

Strauss and Jawhari described it as "ironic" that although the majority of patients in their clinic who require prednisone bursts do not have asthma that was severe enough to qualify them for the controlled clinical trials with mepolizumab, administration of the drug reduced the patients’ need for oral corticosteroids.

The case-series report, “Mepolizumab in the treatment of severe eosinophilic asthma: Results from a physician in the field,” was published in Annals of Allergy, Asthma and Immunology.