How it is administered

Bortezomib is given as an injection, either under the skin (subcutaneous) or directly into a vein (intravenous). It comes as a powder in a single-dose vial that is mixed with a liquid before use. The recommended starting dose is 1.3 mg/m², administered as a quick (3 to 5 second) intravenous injection or as a subcutaneous injection. The dosing schedule and duration depend on the specific condition being treated and may be adjusted based on your body's response and side effects.

For blood cancers, such as multiple myeloma or mantle cell lymphoma, bortezomib is often given in cycles, with rest periods between treatments. Your healthcare team will determine the best schedule for you.

How it works

Bortezomib works by blocking the activity of a protein complex in cells called the 26S proteasome. This proteasome is responsible for breaking down and removing proteins that are damaged or no longer needed. In cancer cells, especially blood cancers like Waldenström's Macroglobulinemia, multiple myeloma, and mantle cell lymphoma, the proteasome is often overactive, helping cancer cells survive and grow.

By inhibiting the proteasome, bortezomib causes a buildup of unwanted proteins inside the cancer cells. This disrupts their normal function and signaling, leading to stress and ultimately cell death. Because cancer cells are more dependent on the proteasome than normal cells, they are more sensitive to its inhibition. This targeted action helps slow or stop the growth of cancer cells and can shrink tumors or reduce disease activity.

Who Should take it

Bortezomib is approved for adults with certain blood cancers, including multiple myeloma and mantle cell lymphoma. While it is not specifically approved for Waldenström's Macroglobulinemia, it may be used off-label for this condition, especially if other treatments have not worked.

It is often given to patients who are newly diagnosed or who have relapsed (the disease has returned) after previous treatments. Your doctor may recommend bortezomib alone or in combination with other medications, depending on your type of blood cancer, your overall health, and your treatment history.

Who should not take it

You should not take bortezomib if you are allergic to bortezomib, boron, or mannitol. Severe allergic reactions, including anaphylaxis, have been reported. Bortezomib must not be given into the spinal canal (intrathecal administration), as this can be fatal.

People with severe peripheral neuropathy (nerve damage causing numbness, tingling, or pain) should only use bortezomib after careful consideration by their doctor. If you have moderate or severe liver problems, your doctor will adjust your dose. Always inform your healthcare team about all your medical conditions and allergies before starting treatment.

Commonly used with

Bortezomib is often used in combination with other medications to treat blood cancers. Common combinations include:

• Melphalan and prednisone (for multiple myeloma)
• Rituximab, cyclophosphamide, doxorubicin, and prednisone (for mantle cell lymphoma, known as the VcR-CAP regimen)
• Dexamethasone (a steroid, sometimes added if response is not optimal)

Your doctor will choose the best combination for you based on your specific diagnosis and health status.

Commonly tested with

Bortezomib has been tested in clinical trials with a variety of other medications, including:

• Dexamethasone
• Melphalan and prednisone
• Rituximab, cyclophosphamide, doxorubicin, and prednisone
• Other chemotherapy agents and targeted therapies

These combinations have been studied to improve treatment outcomes in blood cancers. Your healthcare team will monitor you closely for side effects and effectiveness when using bortezomib with other drugs.