Most of the information presented here is summarized in a table located at the end of this section.
Hydrazine sulfate has been studied extensively in patients with advanced cancer. These studies have evaluated the following: a) tumor response and/or survival among patients with various types of cancer,[1,2,3,4,5,6,7,8,9,10,11,12,13] b) changes in body weight,[1,2,3,4,5,6,8,10,11,12,14] c) carefully measured quality of life,[4,5,6,15] and d) changes in nutritional or metabolic status.[1,4,12,13,16,17]Clinical studies of hydrazine sulfate have been funded by a pharmaceutical company, the Russian government,[7,9,10,18] and by grants from the National Cancer Institute (NCI).[1,2,4,5,6,8,11,12,15,16] They have also been sponsored by the North Central Cancer Treatment Group (NCCTG) [5,6] and the Cancer and Leukemia Group B (CALGB).[4,15]
The first clinical tests of hydrazine sulfate as a treatment for cancer were conducted in the mid-1970s by a pharmaceutical company. In an uncontrolled study of 158 patients with advanced disease, it was found that 45 of 84 evaluable patients had subjective improvements (i.e., the patients reported an increase in appetite, a decrease in weight loss, an increase in strength, or a decrease in pain) and that 14 had objective improvements (i.e., there was measurable tumor regression, stable disease, or improvement in a cancer-related disorder) in response to treatment with hydrazine sulfate. Among the patients with objective responses, two had long-term (17 and 18 months) stabilization of their disease and seven had measurable tumor regression, although the extent and duration of these regressions were not specified. Major weaknesses of this study included the absence of a control (i.e., comparison) group and the fact that 74 of the 158 initially recruited patients could not be evaluated because of poor prognosis, missing documentation, insufficient duration of treatment, and/or concurrent therapy (i.e., therapy given at the same time) with other anticancer drugs.
In 1976, Russian investigators reported findings from 95 patients with advanced cancer who had been treated with hydrazine sulfate after all previous therapy (surgery, chemotherapy, and/or radiation therapy) had failed. Three partial responses (i.e., reductions in tumor size of greater than 50% observed for a period of 4 weeks or more) and no complete responses were noted after 1 to 5 months of treatment. Tumor regressions of 50% or less and stable disease (i.e., cessation of tumor growth for a period of 1.5 to 2.0 months or more) were reported for 16 and 20 patients, respectively.