The U.S. FDA approved denosumab (denosumab, dinosemide, trade name: Xgeva) on November 18, 2010, for the prevention of bone-related events (SREs) in patients with tumors whose cancers have metastasized and compromised bone quality. So-called bone-related events include cancer-induced pathologic fractures, hypercalcemia, surgery or radiotherapy to the bone, and spinal cord compression. However, the approved population for denosumab does not include patients with multiple myeloma or other leukemias. 1.Mechanism of action: Denosumab has a different mechanism of action than the currently approved drugs to reduce the skeletal complications of tumors. It is a fully humanized monoclonal antibody (IgG2 monoclonal antibody) that specifically targets nuclear factor-κB receptor activating factor ligand (RANKL), preventing the binding of RANKL and its receptor material, inhibiting osteoclast activation and development, reducing bone resorption, and increasing bone density. Earlier denosumab (trade name: Prolia) was used to treat osteoporosis in postmenopausal women with a higher risk of fracture, with a favorable safety and efficacy profile. 2. Clinical studies: Cancer bone metastases are an important cause of pain in patients and affect their quality of life. Three randomized-double-blind clinical studies confirmed the safety and efficacy of denosumab, with a total of 5,723 patients participating in the studies. These studies compared denosumab to zoledronic acid in patients with breast cancer, prostate cancer, and a variety of other cancers. The studies were designed to measure the time between when, as a result of cancer, a patient ended up with a fracture or spinal cord compression, or when radiation or surgical treatment was needed to control pain. In patients with prostate cancer, denosumab delayed SREs better than zoledronic acid. The median delay in SREs in patients with prostate cancer was 21 months compared with 17 months for zoledronic acid. In patients with breast cancer, zoledronic acid delayed SREs by a median of 26 months, while denosumab did not reach this level. In patients with other solid tumors, denosumab and zoledronic acid delayed SREs by a comparable median time. The subjects’ main solid tumors were non-small cell lung cancer, multiple myeloma, renal cancer, and small cell lung cancer. 3.Adverse Reactions: The most serious adverse reactions to denosumab were hypocalcemia and osteonecrosis of the jaw. 4.Dosage and Administration: Recommended Dose: Denosumab 120mg subcutaneously for 1/4 week in the upper arm, upper thigh, and abdomen. Calcium and vitamin D may treat or prevent hypocalcemia. Prior to administration, denosumab may be removed from the refrigerator and left at room temperature (up to 25°C/77H) in its original container. This usually takes 15 to 30 minutes. Do not warm by any other method. Aspirate the entire contents of the injection vial with a 27-gauge needle. Do not re-enter the vial, single use or abandon the vial after entry, Dosage form and specification: 120mg/1, 7mL (70mg/mL) single use vial. 5, Preservation: Stored in the refrigerator within 2 to 8 ℃ (36 to 46H) in the original box. Do not freeze, and once removed from the refrigerator, do not expose to temperatures above 25°C/77H or light, and must be used within 14 days. 6. Recommendation: There is insufficient evidence to show that denosumab is clearly superior to any other drug in the prevention of bone-related events, especially in terms of prolonging patient survival. Therefore, the choice should be based on a comprehensive consideration of the patient’s physical condition, economic status, drug toxicity and side effects, and personal preference, with the guideline of maximizing benefit to the patient as the criterion for selection.