Recombinant α-2-interferon for hairy cell leukemia

Twenty-two patients with hairy cell leukemia were treated with biosynthetic (recombinant) α-2-interferon in an open-label, single-arm efficacy study. Patients received 2 x 10⁶ U/m² recombinant α2-interferon three times weekly. Therapy was well tolerated subjectively with minimal short-term hematologic toxicity. Two patients had bacterial infections during the period of study, and one patient experienced a short-lived readily reversible rejection of a corneal transplant. Statistical comparison of the mean hematologic indices at study entry and after three to six months of therapy with recombinant α-2-interferon indicates a significant improvement in hemoglobin, granulocyte, and platelet counts. Bone marrow biopsies in six of 14 patients after six months of therapy showed a > 50% decrease in the infiltration of leukemia cells. We conclude that recombinant α-2-interferon is highly effective therapy for hairy cell leukemia.