Steroid-Sparing Therapy for Hypereosinophilic Syndrome

Patients with nonneoplastic hypereosinophilic syndrome are managed with continuous high-dose glucocorticoids, putting them at risk for a variety of steroid-related adverse effects. Dexpramipexole, a synthetic amino-benzothiazole, was serendipitously observed to reduce eosinophil counts while under evaluation for the treatment of amyotrophic lateral sclerosis.

To examine whether dexpramipexole might play a steroid-sparing therapeutic role in the hypereosinophilic syndrome, investigators conducted a nonrandomized trial in 10 patients with glucocorticoid-responsive disease. Dexpramipexole was given in oral doses of 150 mg twice daily for 12 weeks to determine if the drug could safely decrease the minimum effective steroid dose by ≥50%.

This goal…