Treatment of hairy-cell leukemia with recombinant alpha 2-interferon.

Eleven patients with hairy-cell leukemia (eight with progressive and three with non-progressive disease) were treated with low dose recombinant human alpha 2-interferon. After a 3-month treatment period, nine patients showed an improvement and one patient a partial remission. By then, transfusions were not required any more and serious infections were no longer encountered. Four patients were further treated: three for a total period of 9 months and one for 6 months; all of them reached a partial or complete remission. The treatment was equally effective in patients with both progressive and non-progressive disease. Previous absence of response to splenectomy did not preclude a positive effect of IFN therapy. In two patients, IFN dose reduction was necessary due to unremitting flu-like symptoms.