Overview
11 DESCRIPTION Zoledronic acid injection contains zoledronic acid, a bisphosphonic acid which is an inhibitor of osteoclastic bone resorption. Zoledronic acid is designated chemically as (1-Hydroxy-2-imidazol-1-yl-phosphonoethyl) phosphonic acid monohydrate and its structural formula is: Zoledronic acid is a white crystalline powder.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action The principal pharmacologic action of zoledronic acid is inhibition of bone resorption. Although the antiresorptive mechanism is not completely understood, several factors are thought to contribute to this action. In vitro , zoledronic acid inhibits osteoclastic activity and induces osteoclast apoptosis. Zoledronic acid also blocks the osteoclastic resorption of mineralized bone and cartilage through its binding to bone. Zoledronic acid inhibits the increased osteoclastic activity and skeletal calcium release induced by various stimulatory factors released by tumors. 12.
Indications
- 1 INDICATIONS AND USAGE Zoledronic acid injection is a bisphosphonate indicated for the treatment of: Hypercalcemia of malignancy. (1.1) Patients with multiple myeloma and patients with documented bone metastases from solid tumors, in conjunction with standard antineoplastic therapy. Prostate cancer should have progressed after treatment with at least one hormonal therapy. (1.2) Limitations of Use : The safety and efficacy of zoledronic acid injection has not been established for use in hyperparathyroidism or non-tumor-related hypercalcemia. 1.
Common Doses
- 4 mg
- 60 mL
- 500 mg
- 12 mg
Dosage
2 DOSAGE AND ADMINISTRATION Hypercalcemia of malignancy ( 2.1 ) 4 mg as a single-use intravenous infusion over no less than 15 minutes. 4 mg as retreatment after a minimum of 7 days. Multiple myeloma and bone metastasis from solid tumors. ( 2.2 ) 4 mg as a single-use intravenous infusion over no less than 15 minutes every 3 to 4 weeks for patients with creatinine clearance of greater than 60 mL/min. Reduce the dose for patients with renal impairment. Coadminister oral calcium supplements of 500 mg and a multiple vitamin containing 400 international units of vitamin D daily.
Contraindications
- 4 CONTRAINDICATIONS Hypersensitivity to any component of zoledronic acid injection (4) Hypersensitivity to Zoledronic Acid or Any Components of Zoledronic Acid Injection Hypersensitivity reactions including rare cases of urticaria and angioedema, and very rare cases of anaphylactic reaction/shock have been reported [ see Adverse Reactions (6.2) ].
Side Effects
- 6 ADVERSE REACTIONS The most common adverse events (greater than 25%) were nausea, fatigue, anemia, bone pain, constipation, fever, vomiting, and dyspnea ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Avet Pharmaceuticals Inc. at 1-866-901-DRUG (3784) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in...
Interactions
- 7 DRUG INTERACTIONS Aminoglycosides: May have an additive effect to lower serum calcium for prolonged periods. ( 7.1 ) Loop Diuretics: Concomitant use with zoledronic acid injection may increase risk of hypocalcemia. ( 7.2 ) Nephrotoxic Drugs: Use with caution. ( 7.3 ) In vitro studies indicate that the plasma protein binding of zoledronic acid is low, with the unbound fraction ranging from 60% to 77%. In vitro studies also indicate that zoledronic acid does not inhibit microsomal CYP450 enzymes.