Bone Abstracts

Zoledronic acid (AZ), is considered first-line treatment for Paget’s disease (PD) of bone. The most common adverse event is flu-like syndrome, described between 10 and 50% of patients. Nowadays, there is not known exactly the molecular basis of this syndrome yet. Statins play an important role in the mevalonate pathway, blocking the production of proinflammatory cytokines secreted by T cells γ/δ.

Objectives: Characterization and incidence of adverse events (AEs) secondary to treatment with AZ in patients with PDB. Evaluate the impact of statins on AZ-induced flu-like syndrome.

Methods: A prospective open-label study was conducted in 50 patients with active PD after 2 years period. Each patient received a single 5 mg i.v. infusion of ZA over a 15-min period.

Results: Baseline characteristics of patients with active PD: gender: 50 (23 F/27 M). Mean age at diagnosis (years): 59±12.5. Mean duration of the disease (years): 14.5±8.5. Regarding to AE, there was not hematological, renal, gastrointestinal or liver toxicity detected after infusion of 5 mg ZA nor during the following period. The most frequent side effect was flu-like symptoms, observed in 54% of patients. The incidence of fever was detected in 100% of the patients affected. There was no statistically significant correlation between the presence of flu-like syndrome and a gender, scintigraphic distribution, duration of the disease, number of locations, serum alkaline phosphatase at diagnosis. Instead, it was observed a statistically significant correlation between age at diagnosis, baseline plasma calcium, 1.25-dihydroxyvitamin D3 at baseline and prolonged therapy (>3 m) with statins, with the presence of flu-like syndrome. Patients presenting flu-like symptoms had a lower age at diagnosis, baseline plasma calcium levels below average, plasma levels of 1.25-dihydroxyvitamin D3 above average, and did not maintain statin therapy.

Conclusions: The most important AE was the flu-like symptoms (54%), with mild to moderate intensity. It has been observed that the absence of AE has been correlated with prolonged intake of statins.