Interferon studies in the treatment of patients with leukemia

alpha-Interferon has been studied in a variety of hematologic malignancies. alpha-Interferon has efficacy in the treatment of hairy-cell leukemia, and a recent completed comparison with pentostatin in previously untreated patients will provide important insight into its comparative activity in this treatable disorder. Early clinical trials have demonstrated activity in patients with follicular lymphomas. Additional trials are in progress to determine whether interferon administered in different doses and schedules adds to the activity of established chemotherapeutic regimens in this disease. Lastly, trials with alpha-interferon have produced cytogenetic remissions of the Philadelphia chromosome in approximately 10% to 20% of patients with chronic myelogenous leukemia. Attempts to improve upon these results with the addition of high-dose chemotherapy or gamma-interferon have not been successful, and current trials are in progress evaluating the effects of combination with low-dose chemotherapeutic agents such as cytarabine and hydroxyurea. Further follow-up is necessary to determine whether these cytogenetic changes will translate into long-term survival benefits or prevention of blast crisis. Further understanding of the mechanisms of interferon action could be helpful in preselecting the patients who may benefit from trials with interferon, and indeed other "biologic" agents.