Compliance, toxicity and quality of life in a Phase 3 randomized trial of adjuvant temozolomide versus PCV in grade 2–3 gliomas

Background: Procarbazine, lomustine, vincristine (PCV) and temozolomide (TMZ) are adjuvant therapy options for grade 2 and 3 gliomas. We report compliance, toxicity, and quality of life (QoL) outcomes from an ongoing study comparing these regimens. Objectives: The primary objective was to determine whether adjuvant TMZ is noninferior to PCV in terms of progression-free survival. Secondary objectives were to compare compliance, toxicity, and QoL between the two regimens. Materials and Methods: Adults with high-risk grade 2 or 3 gliomas were randomized (2:1) to receive TMZ or PCV after radiotherapy. The TMZ arm received concurrent TMZ (75 mg/m 2 /day) followed by adjuvant TMZ (150-200 mg/m 2 , days 1-5 every 28 days, up to 12 cycles). The PCV arm received procarbazine (60 mg/m 2 , days 8-21), lomustine (110 mg/m 2 , day 1), and vincristine (1.4 mg/m 2 , days 8 and 29) every 56 days for up to 6 cycles. Results: This analysis included the first 50 patients (TMZ, n = 32; PCV, n = 18). Two patients in each arm did not initiate adjuvant chemotherapy. Chemotherapy completion rates were higher with TMZ (86.7%, n = 26) than PCV (68.8%, n = 11). Dose reductions were significantly more frequent with PCV (68.8%, n = 11 vs 3.3%, n = 1; P < 0.001). Grade ≥3 anemia ( P , 0.011), neutropenia ( P , 0.001), thrombocytopenia ( P , 0.015), and lymphopenia ( P < 0.001) were significantly higher with PCV. QoL did not differ significantly between arms. Conclusion: Adjuvant PCV is feasible with careful monitoring, although it is associated with higher toxicity than TMZ.