- Regimen B: Patients receive cyclophosphamide IV over 3 hours every 12 hours on days 1-3. Doxorubicin is administered IV over 24 hours on days 4 and 5. Vincristine is administered IV over 30 minutes on days 4 and 11. Dexamethasone is administered orally or IV on days 1-4 and 11-14. G-CSF is administered SC beginning on day 6 and continuing until blood counts recover. Treatment repeats every 21 days for up to 7 courses.