Mepolizumab as a glucocorticoid-sparing agent in eosinophilic granulomatosis with polyangiitis (EGPA): is a lower dose sufficient?

Abstract

Introduction

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare form of small-vessel vasculitis characterized by asthma, hyper-eosinophilia, and progressive multiorgan involvement. EGPA is traditionally treated using glucocorticoids, either alone or in combination with conventional immunosuppressants. Mepolizumab, a novel anti-interleukin (IL)-5 agent, has been approved as an add-on therapy for adult patients with EGPA. The recommended dose of mepolizumab is 300 mg (subcutaneous [SC]) every 4 weeks.

Case Study

The present report discusses three cases of refractory and/or relapsing EGPA in patients regularly taking a stable dose of prednisolone, all of whom were successfully treated with a lower-than-recommended dose of mepolizumab (100 mg SC, every 4 weeks).

Results

Treatment with a low dose of mepolizumab enabled us to gradually reduce glucocorticoid doses. In addition, patients treated with low doses of mepolizumab exhibited better asthma control and experienced sustained relapse-free periods. Responses to 100 mg of mepolizumab were comparable to those previously observed in patients taking the recommended dose of 300 mg.

Conclusion

Our findings suggest that mepolizumab at a third of the recommended dose can achieve reasonable clinical efficacy in the long-term treatment of EGPA in some patients. Initiation of mepolizumab therapy in the early, eosinophilic phase of EGPA—which is characterized by asthma, marked blood eosinophilia, pulmonary infiltrates, and sinonasal abnormalities—may help to prevent the deleterious side-effects of long-term glucocorticoid use while reducing the cost of EGPA treatment.

Keywords:

• Case reports
• economics
• pharmacotherapy
• mechanisms

Declaration of interests

MV has received speaker fees and conference grants from Chiesi, Berlin-Chemie Menarini and GSK. ZM has received speaker fees from Abbot Laboratories, AstraZeneca, Berlin-Chemie Menarini and Boehringer Ingelheim, and conference grants from Berlin-Chemie Menarini and Pliva; JTT has received consulting and lecturing fees from Boehringer Ingelheim, and Roche; NT has received fees for speaking and consulting from AstraZeneca, Berlin-Chemie Menarini, Boehringer Ingelheim, Chiesi, GSK, Meda, Novartis, Pliva, and Sandoz.