Therapeutic Classification: antineoplastics
Pharmacologic Classification: monoclonal antibodies
Absorption: IV administration results in complete bioavailability.
Distribution: Binds specifically to CD20 binding sites on lymphoma cells.
Metabolism/Excretion: Unknown.
Half-Life: 59.8174 hr (depending on tumor burden).
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Relapsed or Refractory Low-Grade or Follicular CD20-Positive B-Cell Non-Hodgkins Lymphoma
- IV (Adults ): 375 mg/m2 once weekly for 4 or 8 doses; may retreat with 375 mg/m2 once weekly for 4 doses.
Previously Untreated Follicular CD20-Positive B-Cell Non-Hodgkins Lymphoma
- IV (Adults ): 375 mg/m2 given on Day 1 of each cycle of chemotherapy with cyclophosphamide, vincristine, and prednisone for up to 8 doses; if patients experience complete or partial response, give 375 mg/m2 (as monotherapy) every 8 wk for 12 doses (initiate this maintenance therapy 8 wk after completion of rituximab + cyclophosphamide/vincristine/prednisone regimen).
Nonprogressing Low-Grade CD20-Positive B-Cell Non-Hodgkins Lymphoma
- IV (Adults ): For patients who have not progressed following 68 cycles of chemotherapy with cyclophosphamide, vincristine, and prednisone, 375 mg/m2 given once weekly for 4 doses given every 6 mo for up to 16 doses.
Diffuse Large B-Cell Non-Hodgkins Lymphoma
- IV (Adults ): 375 mg/m2 given on Day 1 of each cycle of chemotherapy for up to 8 infusions.
Previously Untreated Mature B-Cell Lymphomas and B-Cell Acute Leukemia
- IV (Children ≥6 mo): 375 mg/m2/dose in combination with systemic Lymphome Malin B chemotherapy regimen; administer 2 doses during each of the two induction courses (Day −2 and Day 1), and one dose during each of the two consolidation cycles (Day 1) (6 doses total).
Chronic Lymphocytic Leukemia
- IV (Adults ): 375 mg/m2 given on the day before initiating chemotherapy with fludarabine and cyclophosphamide, then 500 mg/m2 on Day 1 of cycles 26 (every 28 days).
Rheumatoid Arthritis
- IV (Adults ): 1000 mg every 2 wk for 2 doses; subsequent courses should be administered every 24 wk (not sooner than every 16 wk).
Granulomatosis With Polyangiitis and Microscopic Polyangiitis
- IV (Adults ): Induction treatment: 375 mg/m2 once weekly for 4 wk; Follow-up treatment in patients who have achieved disease control with induction treatment: 500 mg every 2 wk for 2 doses (should be started 1624 wk after last rituximab induction dose; if achieved disease control with another agent, start follow-up treatment within 4 wk after last induction dose of that agent), then 500 mg every 6 mo thereafter.
- IV (Children ≥2 yr): Induction treatment: 375 mg/m2 once weekly for 4 wk; Follow-up treatment in patients who have achieved disease control with induction treatment: 250 mg/m2 every 2 wk for 2 doses (should be started 1624 wk after last rituximab induction dose; if achieved disease control with another agent, start follow-up treatment within 4 wk after last induction dose of that agent), then 250 mg/m2 every 6 mo thereafter.
Pemphigus Vulgaris
- IV (Adults ): 1000 mg every 2 wk for 2 doses, then maintenance dose of 500 mg infusion at Month 12 and then every 6 mo thereafter. On relapse, administer 1000 mg.