ALPHA-INTERFERON TREATMENT OF IDIOPATHIC MYELOFIBROSIS

Idiopathic myelofibrosis is a chronic myeloproliferative syndrome for which there is no effective treatment. The good results obtained with interferon in other chronic myeloproliferative syndromes have led thei r being tested in idiopathic myelofibrosis, but to date the experience is scarce. Four patients out of a total of 12 diagnosed with idiopath ic myelofibroses over a period of 3 years were selected for interferon treatment. Patients with low leukocyte or platelet counts or with con traindication for administration of the drug were excluded. Alpha-2b i nterferon was administered at an initial dose of 3 MU/day which was in creased at 4-6 weeks to 5 MU/day in cases of insufficient response and if tolerance so permitted. In patients in whom favorable response was observed a maintenance schedule was initiated with low doses of inter feron. Treatment was discontinued in two patients due to bad tolerance at 6 and 8 weeks of initiation of treatment with no response having b een observed until that time. In the other patients favorable response was reported to interferon after 5 months of treatment with disappear ance of the symptomatology, normalization of the hemoperipheral values and a marked reduction of splenomegaly. This response was accompanied by a decrease in bone marrow fibrosis in one case and total disappear ance of the same in the other patient. Alpha-2b interferon constitutes an effective therapy for a selected number of patients with idiopathi c myelofibrosis. Greater experience would allow the identification of the subgroup of patients who may benefit from this type of treatment.