TREATMENT OF CHRONIC MYELOID-LEUKEMIA WITH INTERFERON-ALPHA (ROFERON)- RESULTS OF THE ISRAELI STUDY-GROUP ON CML

Thirty patients with chronic myeloid leukemia from 11 Israeli medical centers entered this study. Their ages ranged from 16-65 (median 4 1 ) and time from diagnosis to treatment was 1-16 months (median 4 months ). After cytoreductive therapy with hydroxyurea (22 patients) or busul phan (8 patients), patients received 9 million units/day of recombinan t interferon alpha-2alpha (Roferon A) subcutaneously. Side effects inc luded arthralgia or low back pain in 7 patients, thromblocytopenia in 9, weight loss in four, neurologic disturbances in 4 and leukopenia in 3 cases. Seventeen patients achieved complete hematologic remission ( CHR) and 6 partial hematologic remission (PHR). Six patients achieved major cytogenetic response. 4 of them lost all Ph1 chromosome positive cells and 4 had minimal cytogenetic response. Frequency of relapse wa s high: 8 patients with CHR and 6 with PHR relapsed, but patients with major cytogenetic response did not relapse. Patients who had received prior therapy with busulphan had a higher remission rate but a lower quality of cytogenetic response. Escalation of Roferon to 12 million u nits per day in relapsing or nonresponding patients induced PHR in 2/7 . Neutralizing anti-interferon antibodies occurred in 7 relapsing or n onresponding patients. The cytoreductive induction with hydroxyurea en hanced the hematologic remissions to a median of 6 weeks. Further stud ies should define the role of combination therapy in order to improve response and prevent relapses.