Common brand names

• Riabni
• Rituxan
• Ruxience
• Truxima

How it is administered

Rituximab is administered as an intravenous (IV) infusion by a healthcare professional. It comes in single-dose vials that are diluted and infused over several hours. The infusion rate is gradually increased if no reactions occur. For some conditions, a faster 90-minute infusion may be used after the first dose if tolerated. Rituximab should never be given as a rapid IV push or bolus.

For certain conditions, rituximab can also be given as a subcutaneous injection (under the skin), but this is not the standard for all indications. The dosing schedule and number of infusions depend on the specific disease being treated and whether rituximab is used alone or in combination with chemotherapy.

How it works

Rituximab is a monoclonal antibody that targets a protein called CD20 found on the surface of certain B-cells, which are a type of white blood cell. In blood cancers like Hairy Cell Leukemia and other B-cell lymphomas, these cells grow uncontrollably. Rituximab binds to CD20 on these cells and helps the immune system recognize and destroy them.

The destruction of B-cells by rituximab happens through several mechanisms, including complement-dependent cytotoxicity (where the immune system's complement proteins help kill the cell), antibody-dependent cell-mediated cytotoxicity (where immune cells are recruited to destroy the target cell), and direct induction of cell death. After treatment, B-cell levels drop and usually recover over several months. This targeted action helps reduce the number of cancerous or abnormal B-cells in the body, improving symptoms and controlling the disease.

Who should take it

Rituximab is indicated for adults (and some pediatric patients for certain conditions) with various blood cancers, including:

• Non-Hodgkin's Lymphoma (NHL), including follicular lymphoma and diffuse large B-cell lymphoma
• Chronic Lymphocytic Leukemia (CLL)
• It is also used for other autoimmune conditions and in combination with chemotherapy for some cancers.

For Hairy Cell Leukemia specifically, rituximab may be used in certain cases, especially when other treatments are not suitable or if the disease is refractory (not responding) to standard therapies. Your doctor will determine if rituximab is appropriate based on your diagnosis, previous treatments, and overall health.

Who should not take it

Rituximab should not be used in patients with:

• Known severe allergic reactions (hypersensitivity) to rituximab or any of its components
• Active, severe infections

Caution is needed in patients with a history of hepatitis B, as rituximab can cause reactivation of the virus. It is also not recommended for use during pregnancy due to potential harm to the fetus, and women should use effective contraception during treatment and for 12 months after the last dose. Live vaccines should not be given before or during rituximab treatment.

Always discuss your full medical history with your healthcare provider before starting rituximab.

Commonly used with

Rituximab is often used in combination with chemotherapy regimens for blood cancers. For example:

• With CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) for diffuse large B-cell lymphoma
• With CVP (cyclophosphamide, vincristine, prednisone) for follicular lymphoma
• With fludarabine and cyclophosphamide for CLL

It may also be used as a single agent or as maintenance therapy after initial treatment. Your doctor will tailor the regimen to your specific disease and health status.

Commonly tested with

In clinical studies, rituximab has been tested with various chemotherapy combinations, such as CHOP, CVP, and FC (fludarabine and cyclophosphamide). It has also been studied as a single agent and as part of maintenance therapy protocols.

For Hairy Cell Leukemia, rituximab may be tested in combination with other agents or after failure of standard therapies. Your care team will discuss the best evidence-based options for your situation.