What is the recommended initial dosing for Truxima (rituximab) in patients with non-Hodgkin's lymphoma?

Recommended Initial Dosing for Truxima (Rituximab) in Non-Hodgkin's Lymphoma

The recommended initial dosing for Truxima (rituximab) in patients with non-Hodgkin's lymphoma is 375 mg/m² administered intravenously once weekly for 4 weeks. 1

Dosing Recommendations Based on NHL Type

Indolent NHL (Follicular Lymphoma)

• First-line therapy: Rituximab 375 mg/m² IV weekly for 4 doses, either as monotherapy or in combination regimens 1
• For elderly or infirm patients: Rituximab 375 mg/m² IV weekly for 4 doses (preferred option for those who cannot tolerate combination therapy) 1
• When used in combination regimens such as:
  • Bendamustine + rituximab (category 1 recommendation) 1
  • RCHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) (category 1) 1
  • RCVP (rituximab, cyclophosphamide, vincristine, prednisone) (category 1) 1

Aggressive NHL (Diffuse Large B-Cell Lymphoma)

• When used in combination regimens such as RCHOP: Rituximab 375 mg/m² IV per cycle 1
• The addition of rituximab to CHOP has consistently increased overall response rate, response duration, progression-free survival, and in some studies, overall survival 1

Maintenance Therapy Considerations

• For patients initially presenting with high tumor burden: Rituximab maintenance 375 mg/m² one dose every 8 weeks for 12 doses (category 1) 1
• For patients initially treated with single-agent rituximab: Consolidation with rituximab 375 mg/m² one dose every 8 weeks for 4 doses 1
• Second-line maintenance: Rituximab 375 mg/m² one dose every 12 weeks for 2 years (category 1, optional) 1

Clinical Evidence Supporting Dosing

• In pivotal trials, rituximab at 375 mg/m² weekly for 4 weeks produced objective response rates of approximately 48% in patients with relapsed or refractory indolent NHL 2
• In previously untreated patients with indolent NHL, rituximab monotherapy at this dose achieved response rates of 54-64% 3, 4
• Serum rituximab concentrations essentially double from the first (239.1 mg/L) to the fourth (460.7 mg/L) infusion due to saturation of CD20-binding sites 2

Important Considerations and Precautions

• Monitor for infusion-related reactions, which occur in the majority of patients but are usually mild to moderate; approximately 10% may develop severe reactions (e.g., bronchospasm, hypotension) 2
• Consider prophylaxis for tumor lysis syndrome in high-risk patients 1
• Monitor for viral reactivation, particularly hepatitis B virus (HBV) 1
• Progressive multifocal leukoencephalopathy (PML) is a rare but serious complication; monitor for neurological symptoms 1

Special Population Considerations

• For chronic lymphocytic leukemia (CLL), a higher dose of 500 mg/m² has been approved, but this is not applicable to NHL patients 5
• For elderly or infirm patients who cannot tolerate combination therapy, single-agent rituximab at 375 mg/m² weekly for 4 doses is preferred 1

The consistent dosing recommendation across multiple guidelines and clinical trials supports the 375 mg/m² weekly for 4 weeks as the standard initial dosing for rituximab in NHL patients, with strong evidence for improved outcomes in both indolent and aggressive NHL subtypes 1, 3, 2.