How it is administered

Rituximab is administered as an intravenous (IV) infusion by a healthcare professional. It is available in single-dose vials that are diluted and given through a vein over several hours. The infusion schedule and dose depend on the condition being treated and the patient's body surface area. For some conditions, such as non-Hodgkin's lymphoma or chronic lymphocytic leukemia, rituximab is given in cycles, often in combination with chemotherapy. Premedication with acetaminophen and an antihistamine is recommended before each infusion to reduce the risk of infusion-related reactions.

How it works

Rituximab is a monoclonal antibody that targets the CD20 protein found on the surface of certain white blood cells called B-lymphocytes (B-cells). By binding to CD20, rituximab helps the immune system recognize and destroy these B-cells. This is particularly important in blood cancers like lymphomas and leukemias, where abnormal B-cells multiply uncontrollably. The destruction of B-cells occurs through several mechanisms, including direct cell killing, activation of the immune system to attack the cells, and triggering processes that lead to cell death.

In blood cancers, reducing the number of abnormal B-cells can help control the disease and improve symptoms. After treatment, normal B-cells usually recover over time, but it may take several months to a year for the immune system to return to normal.

Who Should take it

Rituximab is indicated for adults (and some children, depending on the specific product and indication) with certain types of blood cancers, including:

• Non-Hodgkin's lymphoma (NHL), including follicular lymphoma and diffuse large B-cell lymphoma (DLBCL)
• Chronic lymphocytic leukemia (CLL)

It is often used in combination with chemotherapy, but can also be given as a single agent or as maintenance therapy to help keep the cancer in remission. For some autoimmune diseases, rituximab may also be prescribed, but it is not indicated for non-malignant conditions unless specifically approved.

For rare blood cancers like Large Granular Lymphocytic Leukemia (LGL), rituximab may be used off-label if B-cell involvement is present, but this should be discussed with your healthcare provider.

Who should not take it

Rituximab should not be used in patients with a known severe allergic reaction to rituximab or any of its components. It should also be avoided in patients with severe, active infections, as it can further suppress the immune system and increase the risk of complications.

Patients with active hepatitis B infection should not start rituximab until the infection is treated, as rituximab can cause hepatitis B reactivation, which can be life-threatening. Pregnant women should avoid rituximab due to the risk of harm to the unborn baby. If you are planning to become pregnant, discuss this with your doctor before starting treatment.

Commonly used with

Rituximab is commonly used in combination with chemotherapy agents such as:

• Cyclophosphamide
• Vincristine
• Prednisone
• Doxorubicin
• Fludarabine

It may also be used with other supportive medications, such as acetaminophen, antihistamines, and sometimes corticosteroids, to reduce the risk of infusion reactions.

Commonly tested with

Rituximab is frequently tested in combination with standard chemotherapy regimens for blood cancers, such as CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) or FC (fludarabine, cyclophosphamide). Clinical trials may also evaluate rituximab with newer targeted therapies or as maintenance therapy after initial treatment. Laboratory tests to monitor blood counts, liver and kidney function, and hepatitis B status are commonly performed before and during treatment.