ROCHE's ROFERON-A EFFICACY IN CHRONIC MYELOGENOUS LEUKEMIA

Executive Summary

ROCHE's ROFERON-A EFFICACY IN CHRONIC MYELOGENOUS LEUKEMIA is suggested in a study of 17 patients published in the April 24 issue of the New England Journal of Medicine. Investigators Moshe Talpaz, MD, et al, M. D. Anderson Hospital and Tumor Institute, concluded that the data, which they said are preliminary and need further confirmation, "suggest that recombinant human interferon alpha[a] is effective in inducing hematologic remission in most patients with benign-phase chronic myelogenous leukemia and in suppressing the Philadelphia chromosome in some of these patients." The investigators reported that 17 patients with Philadelphia-chromosome-positive chronic myelogenous leukemia were given daily intramuscular injections of Roferon. The starting dose was 5X10 units per square meter of body-surface. The dose was reduced by 50% if toxicity was observed and increased 100% in cases of treatment resistance or only a minor cytoreductive effect. A hematologic remission "required normalization of the peripheral blood white cell counts, to levels of less than 9X10 per microliter; normalization of the differential cell counts, with no immature forms . . . and the disappearance of all clinical symptoms and signs of disease, including palpable splenomegaly," Talpaz, et al, stated. The authors reported that "14 patients responded to the treatment, of whom 13 had a hematologic remission and one hand a partial hematologic remission. The median number of white cells in those patients declined from 60.9X10 to 3.4X10 per microliter, and the median number of platelets decreased from 476X10 to 231X10 per microliter." Further, the authors noted that "among the five responding patients who had splenomegaly before treatment, the spleen size returned to normal in four and decreased by 75% in one, although it remained enlarged," and "bone marrow cellularity declined from a median of 92.5% to a median of 57.5%." Regarding Philadelphia chromosome suppression, Talpaz, et al, stated that "in six of the patients with hematologic remission, complete suppression of Philadelphia cells was observed on at least one examination." The investigators noted that "of the 14 patients who responded, 11 have received the interferon therapy for 9 to 15 months." They said one patient relapsed during the treatment, and treatment was temporarily interrupted in two patients because of toxicity. Side effects associated with the recombinant human alpha interferon included diffuse neurologic toxicity, which the investigators said occurred in six of the patients. Two of these patients had extrapyramidal symptoms with a Parkinsonian-like syndrome, Talpaz, et al, said. Other side effects included weight loss, mild, dry cough, postnasal drip, arthralgias and myalgias, anemia, and thrombocytopenia, which developed in two patients. The investigators added that "it is notable that the severe muscle and bone pains that were observed during the administration of partially purified alpha-interferon did not occur with recombinant human interferon alpha[a]."