How it is administered

Denosumab is given as a subcutaneous injection (an injection under the skin). It is available in prefilled syringes or vials, typically administered by a healthcare provider.

For bone-related complications in blood cancers (such as multiple myeloma), the usual dose is 120 mg every 4 weeks, injected into the upper arm, upper thigh, or abdomen. For osteoporosis or bone loss due to cancer therapy, the dose is typically 60 mg every 6 months.

Patients are usually advised to take calcium and vitamin D supplements while on denosumab to help prevent low calcium levels.

How it works

Denosumab is a monoclonal antibody that targets and binds to a protein called RANKL (receptor activator of nuclear factor kappa-B ligand). RANKL is essential for the formation, function, and survival of osteoclasts, which are cells that break down bone tissue.

In blood cancers like multiple myeloma, cancer cells can stimulate osteoclasts, leading to increased bone breakdown, bone pain, fractures, and high calcium levels in the blood. By blocking RANKL, denosumab prevents osteoclasts from breaking down bone, helping to maintain bone strength and reduce the risk of fractures and other skeletal-related events. This is especially important for people with blood cancers that affect the bones, as it helps protect bone health and quality of life.

Denosumab's effects are reversible, so if treatment is stopped, bone turnover can increase again. That’s why it’s important to continue therapy as prescribed and discuss any changes with your healthcare provider.

Who Should take it

Denosumab is used in patients with blood cancers, especially multiple myeloma, to prevent skeletal-related events such as bone fractures, spinal cord compression, and the need for radiation or surgery to the bone. It is also used in patients with solid tumors that have spread to the bones.

Additionally, denosumab is indicated for patients with osteoporosis at high risk for fracture, including those receiving hormone therapy for breast or prostate cancer, and for those with glucocorticoid-induced osteoporosis. In the context of blood cancers, its primary use is to protect bone health and reduce complications from bone involvement by cancer.

Who should not take it

Denosumab should not be used in patients with:

• Low blood calcium levels (hypocalcemia) that have not been corrected.
• Known hypersensitivity to denosumab or any of its components (reactions can include anaphylaxis, facial swelling, and urticaria).
• Pregnant women, as it may cause harm to an unborn baby.

Caution is needed in patients with severe kidney problems, as they are at higher risk for low calcium levels. Denosumab is not approved for use in children, except for certain rare bone tumors in skeletally mature adolescents. Patients should not receive denosumab if they are already receiving another denosumab product for a different indication.

Commonly used with

Denosumab is often used alongside other cancer treatments, such as chemotherapy, targeted therapies, or hormone therapies, particularly in patients with multiple myeloma or other cancers that have spread to the bone.

Patients are also advised to take calcium and vitamin D supplements to help prevent low calcium levels while on denosumab.

Commonly tested with

In clinical trials and practice, denosumab has been studied and used in combination with:

• Chemotherapy agents for multiple myeloma (such as bortezomib, lenalidomide, or thalidomide)
• Zoledronic acid (a bisphosphonate, for comparison)
• Hormone therapies (for breast or prostate cancer)

Denosumab is not known to have significant drug interactions with these therapies, but calcium and vitamin D supplementation is recommended to reduce the risk of hypocalcemia.