RESUMEN
SUMMARY: Patients treated with intravenous zoledronic acid 5 mg for osteoporosis may experience post-dose influenza-like symptoms. Oral acetaminophen/paracetamol or ibuprofen administered 4 h post-infusion reduced the proportion of patients with increased oral temperature and worsening post-infusion symptom scores vs. placebo, thus providing an effective strategy for the treatment of such symptoms. INTRODUCTION: Once-yearly intravenous zoledronic acid 5 mg is a safe and effective treatment for postmenopausal osteoporosis. This study assessed whether transient influenza-like post-dose symptoms associated with intravenous infusion of zoledronic acid can be reduced by post-dose administration of acetaminophen/paracetamol or ibuprofen. METHODS: In an international, multicenter, randomized, double-blind, double-dummy parallel-group study, bisphosphonate-naïve postmenopausal women with osteopenia (n = 481) were randomized to receive zoledronic acid 5 mg + acetaminophen/paracetamol (n = 135), ibuprofen (n = 137) or placebo (n = 137), or placebo + placebo (n = 72). Acetaminophen/paracetamol and ibuprofen were administered every 6 h for 3 days beginning 4 h post-infusion. RESULTS: The proportion of patients with increased oral temperature (≥1°C above 37.5°C) and with worsening post-infusion symptom scores over 3 days was significantly lower in patients receiving ibuprofen (36.8% and 48.5%) or acetaminophen/paracetamol (37.3% and 46.3%) vs. those receiving placebo (63.5% and 75.9%, respectively; all p < 0.0001) compared with background rates of 11.1% and 16.7%, respectively, in the absence of any active treatment. Overall incidence of adverse events was comparable for patients receiving acetaminophen/paracetamol or ibuprofen. CONCLUSION: Oral acetaminophen/paracetamol or ibuprofen effectively managed the transient influenza-like symptoms associated with zoledronic acid 5 mg.