Treatment of multiple myeloma with recombinant alpha-interferon.

Thirty-two patients with multiple myeloma were treated with recombinant alpha-interferon clone A (rIFN alpha A) daily by intramuscular injection with an initial dose of 12 X 10(6) U/m2. Of 27 patients evaluable for response, tumor responses were obtained in seven of 14 previously untreated patients (50%) and two of 13 who had relapsed or failed prior chemotherapy (15%). In all patients who had tumor response, there was restoration from subnormal levels of serum immunoglobulins, an effect infrequently observed with chemotherapy. The median duration of tumor responses exceeded 14 months (range, 6 to 20). Moderate-to-severe fatigue was the predominant side effect and necessitated dose reductions in all patients. We conclude that treatment of early stages of multiple myeloma with rIFN alpha A is beneficial because of the substantial response rate and the improvement in the synthesis of serum immunoglobulins. rIFN alpha A has a potential role in combination with other agents in the treatment of multiple myeloma.