- Cohort 2 (R-CHOP-14): Patients receive rituximab IV, cyclophosphamide IV, doxorubicin hydrochloride IV, and vincristine IV on day 1, oral prednisolone on days 1-5, and filgrastim (G-CSF) subcutaneously (SC) on days 5-12. Treatment repeats every 14 days in the absence of disease progression or unacceptable toxicity.