[Interferon alpha--the drug of choice for patients with chronic myeloid leukemia]

The conventional, or standard, treatment of chronic myeloid leukaemia (CML) with hydroxyurea and busulfan has no marked influence on its course or duration. Interferon (IFN) alpha administration has, on the other hand, been shown to induce not only a haematological but also cytogenetic response, i.e. partial or complete bone marrow repopulation by Ph-negative cells. This has triggered studies comparing IFN and conventional chemotherapy. The present work had the purpose to gain experience with IFN alpha treatment and compare the results with hydroxyurea and busulfan treatment, in the chronic phase of CML.

Therapeutic results obtained in 30 patients given IFN alpha and 30 others given conventional chemotherapy were evaluated retrospectively. In spite of the short time of IFN administration (4-27 months), significantly more complete haematological responses (83%) were observed in this than the conventional chemotherapy group (57%). Cytogenetic responses were achieved in 36%, complete cytogenetic remission in 20% of IFN-treated patients. Conventional chemotherapy produced no cytogenetic effect.

The results obtained confirm the value and efficacy of IFN-alpha treatment in CML patients, especially if it is started early and the dose is effective. Regular cytogenetic monitoring is necessary. Longer follow-up of the patients will be necessary for evaluation of the IFN effect on the length of their survival.