Wyost

Bone Complications from Cancer

Wyost is used to prevent serious bone-related problems, such as fractures, spinal cord compression, or the need for radiation or surgery to the bone. It is prescribed for people with:

• Multiple myeloma.
• Solid tumors that have spread to the bone (bone metastases).

Giant Cell Tumor of Bone

This medication is used to treat giant cell tumor of bone in adults and in adolescents whose bones have finished growing. It is typically used when the tumor cannot be surgically removed or when surgery is likely to result in severe complications.

High Calcium Levels

Wyost is used to treat hypercalcemia of malignancy. This is a condition where cancer causes dangerously high levels of calcium in the blood. It is used when the condition does not respond to treatment with bisphosphonates.

Mechanism of Action

Wyost belongs to a class of medications known as RANK ligand (RANKL) inhibitors. It is a monoclonal antibody, which is a type of protein designed to recognize and attach to a specific structure in the body.

In the body, bone is constantly being broken down and rebuilt. Specialized cells called osteoclasts are responsible for breaking down bone tissue. To function, these osteoclasts require a protein called RANK ligand.

Wyost works by:

• Binding to the RANK ligand protein.
• Preventing the protein from activating its receptor on the surface of osteoclasts.
• Reducing the formation, function, and survival of these bone-destroying cells.

By slowing down the process of bone breakdown, Wyost helps to keep bones stronger and decreases the likelihood of fractures or other bone complications associated with certain types of cancer.

Common Side Effects

Some people using Wyost may experience mild to moderate side effects. These often include:

• Tiredness or weakness
• Nausea
• Diarrhea
• Shortness of breath
• Headache
• Cough
• Pain in the back, joints, or muscles

Serious Side Effects

Wyost can cause serious side effects that may require medical intervention. Contact a healthcare provider immediately if you experience:

• Low blood calcium (hypocalcemia): Symptoms include muscle spasms, twitches, cramps, or numbness and tingling in the hands, feet, or face.
• Jaw bone problems (osteonecrosis): Signs include jaw pain, swelling, loose teeth, or slow healing of the gums after dental work.
• Atypical thigh bone fractures: New or unusual pain in the hip, groin, or thigh area.
• Serious infections: This may affect the skin, ears, or bladder. Symptoms include fever, chills, or skin that is red, swollen, or tender.
• Skin reactions: Including dermatitis, rashes, or eczema.
• Severe allergic reactions: Symptoms such as swelling of the face or throat, hives, and difficulty breathing.

Severe Hypocalcemia in Kidney Disease

Wyost has a boxed warning regarding the risk of severe hypocalcemia (dangerously low blood calcium levels). This risk is significantly higher for individuals with advanced chronic kidney disease, especially those requiring dialysis. Severe hypocalcemia can be life-threatening and may lead to hospitalization. Healthcare providers typically monitor calcium levels closely and ensure patients are taking adequate calcium and vitamin D supplements before and during treatment.

Osteonecrosis of the Jaw

This medication may cause osteonecrosis of the jaw (ONJ), a serious condition where the jawbone is exposed and begins to die. This risk is higher for patients with poor oral hygiene, those undergoing invasive dental procedures like tooth extractions, or those with certain medical conditions like cancer or anemia. A dental examination is often recommended before starting treatment, and patients are encouraged to maintain good oral hygiene and avoid invasive dental work while using Wyost.

Atypical Femoral Fractures

Some patients using this medication have developed unusual fractures in the thigh bone (femur). These fractures may occur with little or no trauma. Patients should report any new or unusual pain in the hip, groin, or thigh to their healthcare provider immediately, as this may be a warning sign of a stress fracture.

Hypercalcemia After Stopping Treatment

In patients with growing skeletons (such as children) and those with giant cell tumor of the bone, stopping Wyost can lead to dangerously high blood calcium levels (hypercalcemia). This condition can occur weeks to months after the last dose and may require medical intervention.

Embryo-Fetal Toxicity

Wyost can cause harm to a developing fetus. It is not recommended for use during pregnancy. Individuals who can become pregnant should use effective birth control during treatment and for at least five months after the final dose. If pregnancy occurs, the medication should be discontinued immediately.

Hypersensitivity Reactions

Serious allergic reactions have been reported with denosumab products. Symptoms may include:

• Swelling of the face, lips, tongue, or throat
• Difficulty breathing or swallowing
• Severe rash, itching, or hives
• Low blood pressure

Pregnancy

Wyost can cause harm to an unborn baby and is generally not recommended for use during pregnancy. Animal studies have shown that exposure to denosumab products during pregnancy can lead to an increased risk of fetal loss, stillbirth, and postnatal mortality. It may also interfere with the normal development of the fetus's immune system and bone growth.

If you are able to become pregnant, your healthcare provider may require a pregnancy test before you start treatment to ensure you are not pregnant. Effective contraception should be used during treatment and for at least 5 months after the last dose of Wyost. If you become pregnant while receiving this medication, notify your doctor immediately to discuss the potential risks.

Breastfeeding

It is currently unknown whether Wyost passes into human breast milk. Because many drugs are excreted in human milk and there is a potential for serious side effects in a nursing infant, a decision must be made whether to stop breastfeeding or stop the medication. You should discuss the risks and benefits with your healthcare provider to determine the best course of action based on your medical needs.

Dosage Forms

Wyost is supplied as a sterile, preservative-free solution for injection. It is available in the following form:

• Subcutaneous Injection: A liquid solution administered into the fatty tissue just beneath the skin, typically provided in a single-dose vial.

FDA Approval and Biosimilar Status

Wyost (denosumab-bbdz) was approved by the U.S. Food and Drug Administration (FDA) in March 2024. It is the first interchangeable biosimilar to Xgeva (denosumab). As an interchangeable biosimilar, it has been shown to be highly similar to the reference product, with no clinically meaningful differences in safety or effectiveness. Depending on state laws, an interchangeable product may be substituted for the reference product by a pharmacist without requiring a new prescription from the healthcare provider.

Approved Indications

Wyost is indicated for several conditions related to bone health in patients with cancer:

• Prevention of skeletal-related events in patients with multiple myeloma and in patients with bone metastases from solid tumors.
• Treatment of adults and skeletally mature adolescents with giant cell tumor of bone that is unresectable or where surgical resection is likely to result in severe morbidity.
• Treatment of hypercalcemia of malignancy refractory to bisphosphonate therapy.

Boxed Warning

The FDA-approved labeling for Wyost includes a Boxed Warning regarding the risk of severe hypocalcemia (critically low blood calcium levels) in patients with advanced chronic kidney disease, particularly those on dialysis. This condition can lead to serious complications, including hospitalization or death. Healthcare providers are required to evaluate patients for this risk and monitor calcium levels closely before and during treatment.

Risks of Discontinuation

When Wyost is stopped, its effects on bone metabolism reverse quickly. This can lead to a rapid increase in bone turnover and a subsequent loss of bone mineral density. In some cases, stopping the medication may increase the risk of bone fractures or other skeletal-related events that the drug was intended to prevent.

Severe Hypercalcemia

A significant risk associated with stopping denosumab products like Wyost is the development of severe hypercalcemia (high calcium levels in the blood). This is particularly a concern for patients with giant cell tumor of bone or those with growing skeletons. This rebound effect can occur weeks or months after the last dose is administered and may be severe enough to require hospitalization.

Symptoms of high calcium levels to watch for after stopping treatment include:

• Nausea and vomiting
• Constipation
• Increased thirst and frequent urination
• Muscle weakness
• Confusion or fatigue

Managing Treatment Changes

Because of the risks associated with withdrawal, it is vital to adhere to the injection schedule prescribed by a healthcare provider. If treatment with Wyost must be interrupted or permanently stopped, doctors often transition the patient to a different type of bone-strengthening medication, such as a bisphosphonate, to help maintain bone density and prevent a surge in calcium levels.

Always consult your healthcare provider before missing a dose or stopping Wyost, as they must monitor your calcium levels and bone health closely during and after treatment.