A randomized comparison of two doses of human lymphoblastoid interferon-alpha in hairy cell leukemia. Wellcome HCL Study Group.

One hundred thirty-eight patients with hairy cell leukemia were randomized to receive either a dose of 2.0 megaunits (MU)/m2 or a 10-fold lower dose of 0.2 MU/m2 of a highly purified natural alpha-interferon, administered daily for 28 days followed by a three times a week schedule. Ninety-seven of these patients had previously undergone splenectomy, but otherwise none of the patients had received prior therapy for their leukemia. The two doses were comparable in their effect on improving the neutrophil and platelet count, whereas the higher dose had a greater beneficial effect on the hemoglobin level and a greater antileukemic effect on the marrow. Acute toxicity in the form of a flu-like syndrome, neurologic side effects, neutropenia, and the need for platelet transfusions was observed less frequently in the low-dose group, as was the chronic fatigue syndrome. No neutralizing antibody activity was seen in the sera from 61 patients examined. Because of its beneficial effect on the neutrophil and platelet count and a lower degree of toxicity (ie, a superior therapeutic/toxicity ratio), the low dose is recommended as initial therapy in patients with hairy cell leukemia. This therapy may be followed by dose escalation once clinical improvement is observed.

Interferon-alpha-n1 and continuous infusion vinblastine for treatment of advanced renal cell carcinoma.

Eighteen patients with advanced renal cell carcinoma were treated with human lymphoblastoid interferon (Wellferon) and continuous fusion vinblastine. All patients received vinblastine as a continuous infusion at a dose of 1.5 mg/m2/day on days 1 to 5. The interferon was given by daily intramuscular injections on days 1 to 10. Three patients were treated with a dose escalation scheme that reached a maximum daily dose by day 3 of 5 X 10(6) units/m2/day and that was then continued until day 10. Fifteen patients received 3 X 10(6) units/m2/day on day, 1, and 5 X 10(6) units/m2/day on days 3 to 10. Treatments were repeated every 28 days. Neutropenia (less than 1,500/mm3) occurred in 14 of 18 patients. Transient increases in serum glutamic-oxaloacetic transaminase levels to greater than four times baseline were noted in nine patients. Thrombocytopenia (less than 100,000 platelets/mm3) occurred in one patient. Fatigue, lethargy, and decline in performance status were marked in four of the patients. None of the patients in the low-dose interferon group and only 1 of the 15 patients in the high-dose interferon group had an objective response (7%, with a 95% confidence interval of 0 to 31%). Of the 12 patients completing at least two courses of therapy, 10 were in the high-dose group, which included the 1 objective (partial) response. This response noted at the start of the fourth course. Ten others developed progressive disease and one stopped treatment because of neurologic toxicity.(ABSTRACT TRUNCATED AT 250 WORDS)