Rituximab

Rituximab

What Rituximab Is and How It Works 

Rituximab (available under brand names like Rituxan, Ruxience, Truxima, Riabni) is an immunosuppressant medication. It is a monoclonal antibody that targets and depletes B-lymphocytes by binding to the CD20 antigen on their surface. B cells are thought to contribute to autoimmune diseases by producing autoantibodies, presenting antigens, activating T-cells, and releasing pro-inflammatory substances. By reducing these B cells, rituximab helps manage the autoimmune response.

Conditions Treated 

Rituximab is FDA-approved for rheumatoid arthritis (RA) and ANCA vasculitis. It is also widely used for other autoimmune conditions such as Systemic Lupus Erythematosus (SLE), Sjogren syndrome, and IgG4 related disease.

Administration 

Rituximab is typically given as an intravenous (IV) infusion. The frequency of infusions varies depending on the specific autoimmune disease being treated. Patients usually receive premedication, such as acetaminophen, an antihistamine, and methylprednisolone, before the infusion to help prevent reactions.

Potential Side Effects and Risks

Infusion Reactions

These are relatively uncommon but can include symptoms like hypotension (low blood pressure), rigor (shaking), chills, fever, hypoxia (low oxygen), angioedema (swelling), bronchospasm (airway narrowing).

Infections

Rituximab can increase the risk of various infections, including the reactivation of Hepatitis B and though very rare can be associated with a brain infection called progressive multifocal leukoencephalopathy (PML). If a patient experiences persistent immunodeficiency with recurrent infections, discontinuation of rituximab might be necessary.

Hypogammaglobulinemia

This is a reduction in immunoglobulin levels, which can further increase the risk of infection.

Other Reactions

Less severe reactions can include skin reactions, elevated liver enzymes, gastrointestinal perforation, edema (swelling), hypertension (high blood pressure), fatigue, headache, insomnia, rash, itching, nausea, diarrhea, and weight gain [20].

Important Considerations

Pre-treatment Screening: Before starting rituximab, patients should be screened for Hepatitis B and latent tuberculosis.

Monitoring

Regular monitoring of immunoglobulin levels is important. If IgG levels are too low or if recurrent infections occur, immunoglobulin replacement therapy might be considered.

Contraindications

Rituximab is contraindicated during pregnancy or lactation, and for individuals using inadequate contraception [20].

Vaccinations

Live or live-attenuated vaccines are generally not recommended during or shortly before rituximab treatment. Non-live vaccines should ideally be administered at least two weeks before starting treatment, if possible.

Communication with Provider

Patients should discuss the purpose of the medication, follow-up care, and potential side effects with their healthcare provider.

This information is not a substitute for professional medical advice. Always discuss your specific situation with your healthcare provider.