From the Guidelines
The recommended dosage of Rituximab (Rituxan) is 375 mg/m2 intravenously, with the treatment schedule varying by condition being treated, and the most recent evidence suggests eight infusions of rituximab are applied as the recommended standard 1.
Dosage Variations
The dosage of Rituximab varies depending on the condition being treated.
- For rheumatoid arthritis, the standard dose is 1,000 mg given as an intravenous infusion, repeated two weeks later.
- For most non-Hodgkin lymphomas, the typical dose is 375 mg/m² given weekly for 4-8 weeks, often combined with chemotherapy.
- For chronic lymphocytic leukemia, 375 mg/m² is given for the first cycle, followed by 500 mg/m² for subsequent cycles.
- For granulomatosis with polyangiitis and microscopic polyangiitis, 375 mg/m² is administered once weekly for 4 weeks.
Administration and Monitoring
The first infusion should be given slowly (50 mg/hour initially) and gradually increased if tolerated, with subsequent infusions potentially given at faster rates.
- Premedication with acetaminophen and an antihistamine is recommended before each infusion to reduce infusion reactions.
- Patients should be monitored closely during infusions for reactions including fever, chills, and hypotension.
Mechanism of Action
Rituxan works by targeting CD20-positive B cells, depleting them from circulation, which explains its effectiveness in B-cell malignancies and autoimmune conditions where B cells play a pathogenic role.
Recent Evidence
The most recent evidence from 2024 suggests that eight infusions of rituximab are applied as the recommended standard 1, while other studies have shown varying response rates and relapse rates depending on the condition being treated 1.
From the FDA Drug Label
The recommended dose is 375 mg/m2 as an intravenous infusion according to the following schedules: Relapsed or Refractory, Low-Grade or Follicular, CD20-Positive, B-Cell NHL Administer once weekly for 4 or 8 doses. Retreatment for Relapsed or Refractory, Low-Grade or Follicular, CD20-Positive, B-Cell NHL Administer once weekly for 4 doses Previously Untreated, Follicular, CD20-Positive, B-Cell NHL Administer on Day 1 of each cycle of chemotherapy for up to 8 doses. In patients with complete or partial response, initiate RITUXAN maintenance eight weeks following completion of a rituximab product in combination with chemotherapy. Administer RITUXAN as a single-agent every 8 weeks for 12 doses Non-progressing, Low-Grade, CD20-Positive, B-Cell NHL, after first-line CVP chemotherapy Following completion of 6–8 cycles of CVP chemotherapy, administer once weekly for 4 doses at 6-month intervals to a maximum of 16 doses. Diffuse Large B-Cell NHL Administer on Day 1 of each cycle of chemotherapy for up to 8 infusions Pediatric patients aged 6 months and older with previously untreated mature B-cell NHL/B-AL RITUXAN is given in combination with systemic Lymphome Malin B (LMB) chemotherapy. In total, six infusions of RITUXAN are given, two doses during each of the induction courses, COPDAM1 and COPDAM2, and one dose during each of the two consolidation courses of CYM/CYVE The recommended dose is 375 mg/m2 the day prior to the initiation of FC chemotherapy, then 500 mg/m2 on Day 1 of cycles 2–6 (every 28 days). When used as part of the Zevalin therapeutic regimen, infuse 250 mg/m2 in accordance with the Zevalin package insert. Administer RITUXAN as two-1,000 mg intravenous infusions separated by 2 weeks. Subsequent courses should be administered every 24 weeks or based on clinical evaluation, but not sooner than every 16 weeks. Induction Treatment of Adult Patients with Active GPA/MPA Administer RITUXAN as a 375 mg/m2 intravenous infusion once weekly for 4 weeks Follow up Treatment of Adult Patients with GPA/MPA who have achieved disease control with induction treatment Administer RITUXAN as two 500 mg intravenous infusions separated by two weeks, followed by a 500 mg intravenous infusion every 6 months thereafter based on clinical evaluation Induction treatment of Pediatric Patients with Active GPA/MPA Administer RITUXAN as a 375 mg/m2 intravenous infusion once weekly for 4 weeks Follow up Treatment of Pediatric Patients with GPA/MPA who have achieved disease control with induction treatment Administer RITUXAN as two 250 mg/m2 intravenous infusions separated by two weeks, followed by a 250 mg/m2 intravenous infusion every 6 months thereafter based on clinical evaluation
The recommended dosage of Rituximab (Rituxan) varies depending on the condition being treated.
- Non-Hodgkin's Lymphoma (NHL): 375 mg/m2 as an intravenous infusion, administered according to specific schedules.
- Chronic Lymphocytic Leukemia (CLL): 375 mg/m2 the day prior to the initiation of FC chemotherapy, then 500 mg/m2 on Day 1 of cycles 2–6.
- Rheumatoid Arthritis (RA): two 1,000 mg intravenous infusions separated by 2 weeks.
- Granulomatosis with Polyangiitis (GPA) and Microscopic Polyangiitis (MPA): 375 mg/m2 intravenous infusion once weekly for 4 weeks for induction treatment, and two 500 mg intravenous infusions separated by two weeks for follow-up treatment. 2
From the Research
Recommended Dosage of Rituximab
The recommended dosage of Rituximab (Rituxan) varies depending on the condition being treated.
- For non-Hodgkin's lymphoma, the standard regimen is 375 mg/m² weekly for 4 weeks 3.
- For rheumatoid arthritis, the recommended dosage is 1,000 mg on days 1 and 15 4, 5.
- For adult immune thrombocytopenia, a regimen of 1,000 mg on days 1 and 15 has been shown to be effective and safe 5.
Infusion Rate
The infusion rate of Rituximab can also vary.
- The standard infusion rate is over 4.25 hours for the first infusion and 3.25 hours for subsequent infusions 6.
- However, studies have shown that a faster infusion rate of 2 hours 6 or 90 minutes 7 can be safe and well-tolerated for subsequent infusions.
Factors Affecting Dosage
Several factors can affect the dosage and efficacy of Rituximab, including: