Aclasta

Zoledronic acid belongs to the class of nitrogen-containing bisphosphonates and acts primarily on bone. It is an inhibitor of osteoclast-mediated bone resorption. The action of bisphosphonates on bone is based on their high affinity for mineralized bone. Intravenously administered Zoledronic acid is rapidly distributed to bone. The main molecular target of Zoledronic acid in the osteoclast is the enzyme farnesyl pyrophosphate synthase, but this does not exclude other mechanisms. There was no accumulation of the active substance in plasma after multiple doses given every 28 days. Zoledronic acid is not metabolized and is excreted unchanged via the kidney.

Specific drug-drug interaction studies have not been conducted with Zoledronic acid. Zoledronic acid is eliminated by renal excretion. Caution is indicated when Zoledronic Acid is administered in conjunction with drugs that can significantly impact renal function (e.g. aminoglycosides or diuretics that may cause dehydration).

The post-dose side-effects are fever, myalgia, flu-like symptoms, arthralgia and headache, the majority of which occur within the first 3 days following Zoledronic Acid administration. The majority of these symptoms were mild to moderate in nature and resolved within 3 days of the event onset. The incidence of these symptoms occurring within the first 3 days after administration of Zoledronic Acid, can be reduced with the administration of Paracetamol or Ibuprofen shortly following Zoledronic Acid administration. Severe and occasionally incapacitating bone, joint, and/or muscle pain have been infrequently reported in patients taking Zoledronic Acid.

Zoledronic Acid is contraindicated during pregnancy and in breast-feeding women. It is also not recommended for use in children and adolescents below 18 years of age.

Patients must be appropriately hydrated prior to administration of Zoledronic Acid. This is especially important in the elderly and for patients receiving diuretic therapy. Adequate hydration can be achieved by the patient drinking two glasses of fluid (such as water) before and after the infusion. Pre-existing hypocalcaemia must be treated by adequate intake of Calcium and Vitamin-D before initiating therapy with Zoledronic Acid. Other disturbances of mineral metabolism must also be effectively treated (e.g. diminished parathyroid reserve, thyroid surgery, parathyroid surgery, intestinal Calcium malabsorption). Physicians should consider clinical monitoring for these patients.

Patients with renal impairment: The use of Zoledronic Acid in patients with creatinine clearance <35 mL/min is not recommended due to limited clinical safety data in such patients. No dose adjustment is necessary in patients with creatinine clearance >35 mL/min.

Patients with hepatic impairment: No dose adjustment is required for patients with hepatic impairment.

Elderly patients: No dose adjustment is required. However, because decreased renal function occurs more commonly in the elderly, special care should be taken to monitor renal function.

Zoledronic Acid must not be mixed or given intravenously with any other medication and must be given through a separate infusion line at a constant infusion rate. If refrigerated, allow the refrigerated solution to reach room temperature before administration. Aseptic techniques must be followed during the preparation of the infusion. Any unused solution should be discarded. Only clear solution free from particles and discoloration should be used.

After opening, the solution is chemically and physically stable for at least 24 hours at 2°C to 8°C. From a microbiological point of view, the product should be used immediately. Zoledronic Acid solution for infusion must not be allowed to come into contact with any Calcium or other divalent cation-containing solutions.

Bisphosphonate preparations

Clinical experience with acute over dosage is limited. Patients who have received doses higher than those recommended should be carefully monitored. In the event of overdose leading to clinically significant hypocalcaemia, reversal may be achieved with supplemental oral Calcium and/or an infusion of Calcium.

Store below 30° C prior to opening. Protect from moisture and light. Zoledronic Acid must be kept out of the reach and sight of children.