[Treatment of leukemias and lymphomas with interferons: I. Trial of myeloma therapy with human beta-interferon].

Eighteen patients with malignant gammapathies (16 with myeloma and 2 with Waldenström's disease) for a short time because in a phase II-I trial were treated with human (IF beta) given i. v. 6 X 10(6) units weekly (7 patients) or 3 X 10(6) units twice weekly (11 patients) during at least 3 months if tolerated. Treatment was discontinued because of side-effects in three patients. Reduction of the M component of at least 25% from the initial value was obtained in 3 patients. In one case, was also observed in disappearance of the urinary Bence-Jones protein, in 4 cases a significant reduction of bone marrow infiltration by plasma cells and, in 5 cases, major alleviation or disappearance of bone pain. Length of treatment seems an important factor for activity. Immune monitoring with currently available tests, mainly NK cell activity, yielded no correlation with therapeutic effect in these patients. This very preliminary study demonstrates the effect of fibroblastic interferon in myeloma, but further studies are mandatory to determine the population of patients likely to benefit from treatment, the best modalities, possible special indication, dose schedule and duration of treatment. Interferon, however, already appears in this population of patients as giving results similar to those of single agent chemotherapy. As it is not myelosuppressive, it could be indicated in that frequent situation of advanced myeloma with bone marrow failure contra-indicating combination chemotherapy.