Final analysis of the ECOG I-COPA trial (E6484) in patients with non-Hodgkin's lymphoma treated with interferon alfa (IFN-alpha 2a) plus an anthracycline-based induction regimen

The Eastern Cooperative Oncology Group (ECOG) performed a prospectively ran domized study (E6484) evaluating the use of interferon alfa 2a (IFN-alpha 2 a) in patients with aggressive low-grade or with intermediate-grade non-Hod gkin's lymphoma (NHL) accruing close to 300 patients between 1985 and 1988. patients were eligible for study if they had bulky or symptomatic low-grad e lymphoma or defined intermediate-grade subtypes. Of 291 patients enrolled , 249 were eligible for analysis. Ali patients were randomized to receive a four-drug cytotoxic chemotherapy regimen including cyclophosphamide, doxor ubicin, vincristine and prednisone in 4-week cycles with or without IFN-alp ha 2a in addition (COPA vs I-COPA). Treatment was given for up to 8-10 mont hs. This report, at a time when the median follow-up among survivors has re ached 12 years, updates the analysis of time to treatment failure (TTF), du ration of disease-free survival (DFS), and overall survival. Patients rando mized to receive IFN-alpha 2a had a prolonged TTF (P = 0.008; median 2.4 vs 1.6 years), DFS for those patients who had complete responses was also lon ger if IFN-alpha 2a had been given (P = 0.035; median 2.1 vs 1.8 years). Th ere was a clinically but not a statistically significant prolongation of ov erall survival by IFN-alpha 2a (P = 0.107; median 7.8 vs 5.7 years). There were fewer deaths over time due to lymphoma in patients receiving IFN-alpha 2a (67 vs 80 deaths). A subset analysis, based on disease histology (low-g rade, follicular, intermediate-grade), revealed a significant prolongation of TTP in patients receiving IFN-alpha 2a with either low-grade (P = 0.002; median 2.4 vs 1.6 years) or follicular (P = 0.01; median 2.5 vs 1.7 years) NHL but not intermediate grade (P = 0.622; median 2.3 vs 1.6 years) NHL. T his analysis, performed approximately 12 years after closure of the study t o accrual, supports the addition of interferon alfa to an induction cytotox ic chemotherapy regimen including cyclophosphamide and doxorubicin in the t reatment of follicular NHL.