Intensive combination chemotherapy and interferons in the management of chronic myelogenous leukemia

Compared to single-agent therapy with hydroxyurea or myleran (155 patients), intensive chemotherapy with vincristine, cytosine arabinoside, prednisoneand cyclophosphamide (60 patients) or anthracyc-lines (37 patients) showed significant survival improvement overall (p<0.01) and among intermediate-and high-risk patients. Of 51 patients treated with human leukocyte alpha interferon (IFN-α), 36 (71%) had complete hematologic remission (CHR); 20 patients (39%) showed Ph suppression which was persistent in 13 for >21 months. Survival was better in patients obtaining remission with IFN-α. Recombinant gamma interferon (IFN-γ) was also active in chronic myelogenous leukemia. Therapy with combined IFN-α + IFN-γ has been initiated. Compared to the expected survival, the observed survival is favorable for IFN-α and the combined chemotherapy and IFN-α programs. Future therapeutic trials will incorporate initial IFN therapy followed by cyclic intensive chemotherapy at 6-month intervals and IFN maintenance between chemotherapy cycles.