Acute Adverse Events Following Intravenous Bisphosphonate Infusion Are Uncommon in Patients With Duchenne Muscular Dystrophy Previously Treated With Oral Bisphosphonates.

INTRODUCTION/AIMS: Bisphosphonates are the standard treatment for osteoporosis in patients with Duchenne muscular dystrophy (DMD) undergoing long-term glucocorticoid therapy. In this study, we aimed to assess the short-term safety of intravenous bisphosphonates in a distinct group of patients with DMD, most of whom had previously been treated with oral bisphosphonates.

METHODS

We conducted a retrospective chart review of patients with DMD who had received intravenous zoledronic acid infusions at Cincinnati Children's Hospital Medical Center between January 2011 and March 2025. Primary outcomes were acute phase reactions (APR), hypocalcemia, and hypophosphatemia.

RESULTS

Forty-six patients (median age 17.5 years, IQR: 14.8-19.9) received 259 zoledronic acid infusions (median of 4 infusions per patient, IQR: 2-7). The majority of patients (44/46) had been treated with alendronate prior to receiving zoledronic acid for a median duration of 6.5 years (IQR: 3.9-9.3). Acute adverse events were rare with the first infusion in patients previously treated with alendronate: mild APR occurred in 12%, hypocalcemia in 3%, and hypophosphatemia in 8%. In contrast, both bisphosphonate-naïve patients experienced acute adverse events. With subsequent infusions, acute adverse events were uncommon among patients previously treated with alendronate (APR 6%, hypophosphatemia 3%).

DISCUSSION: Acute adverse events from zoledronic acid infusions were uncommon and manageable in patients with DMD previously treated with alendronate. It is possible that prior alendronate therapy may have mitigated the development of acute adverse events related to zoledronic acid infusions in these patients.