MABTHERA® (rituximab) 500 mg is a monoclonal antibody therapy used in rheumatology, immunology, and oncology to treat autoimmune diseases and certain blood cancers. In rheumatology, MABTHERA® is prescribed for adults with severe active rheumatoid arthritis who have had an inadequate response or intolerance to other disease-modifying antirheumatic drugs (DMARDs), including TNF inhibitors. It works by targeting and depleting CD20-positive B-cells, reducing autoimmune-driven inflammation and joint damage.

Key Benefits
• Effective treatment for severe rheumatoid arthritis unresponsive to standard therapies
• Targets CD20-positive B-cells, reducing autoimmune activity
• Helps decrease joint inflammation, pain, and swelling
• Contributes to slowing structural joint damage
• Also indicated for GPA and MPA (ANCA-associated vasculitis) under rheumatology care

How It Works
MABTHERA® contains rituximab, a monoclonal antibody that binds to CD20 on the surface of B-cells. This leads to selective B-cell depletion through immune-mediated mechanisms. By reducing pathogenic B-cell activity, MABTHERA® helps control autoimmune inflammation and improves disease symptoms over time.

Ideal Candidates
• Adults with severe active rheumatoid arthritis who have not responded adequately to one or more TNF inhibitors
• Patients diagnosed with GPA (Granulomatosis with Polyangiitis) or MPA (Microscopic Polyangiitis)
• Individuals requiring a biologic therapy that targets B-cells rather than T-cell–mediated pathways

Administration
Supplied as a 500 mg intravenous concentrate for infusion.
Administration is performed in a clinical setting under medical supervision. Treatment typically involves two infusions given two weeks apart, with repeated cycles scheduled based on patient response and clinical assessment. Pre-medication is often used to reduce the risk of infusion reactions.

Possible Side Effects
Common side effects may include infusion-related reactions, fever, chills, fatigue, mild hypotension, or rash during or shortly after infusion.
More serious risks include increased susceptibility to infections, rare severe infusion reactions, or hematologic abnormalities. Patients must be monitored throughout treatment and between cycles.