Recombinant alpha interferon in the treatment of low-grade non-Hodgkin's lymphoma: results of a cooperative phase II trial in 31 patients.

Thirty-one patients with advanced stage of favorable histology non-Hodgkin's lymphomas were entered into a multicenter phase II trial with recombinant alpha A interferon as single agent. Interferon was administered intramuscular in doses of 6 x 10(6)/IU/m2 three times per week for 12 weeks. Dose escalation was applied, in the absence of toxicities greater than WHO grade II, in patients not responding after 4 weeks. In responding patients treatment was continued at the same dose with a weekly maintenance schedule for 12 additional weeks. Objective responses (4 complete, 10 partial) were obtained in 14 of the 27 evaluable patients (52%). Median time to progression was 15 months for partial responders, while none of the complete responders has relapsed up to the present time. Toxicity was generally moderate and manageable. Treatment was discontinued in three patients because of side effects, and one patient refused therapy after 3 weeks. Our study shows that recombinant alpha A interferon has antitumor activity in patients with favorable histology non-Hodgkin's lymphoma.