A hitherto unreported high incidence of zoledronic acid-induced acute phase reaction in patients with cancer treatment-induced bone loss

Abstract

The major adverse effect of i.v. administration of aminobisphosphonates (N-BPs) [such as pamidronate and zoledronic acid (ZA)] is the development of an acute-phase response (APR) in about one-third of patients who receive the treatment for the first time [1]. The APR is maximal within 28–36 h of i.v. administration and disappears 2–3 days later, despite continuing treatment. This reaction is characterized by a transient pyrexia and increased circulating levels of interleukin-6 (IL-6), tumor necrosis factor (TNF) and interferon (IFN) [2–4]. The reported incidence is variable, ranging between 10% and 50% in osteoporotic, pagetic and cancer patients according to the type of N-BP administration [5], and also to the different assessment criteria used to classify the APR.