[Principles of the clinical study of new antitumor perparations]

Clinical studies on new antitumor drugs are characterized by a number of features different from testing other drugs and may be divided into 3 phases, each having its specific aims. Of greatest importance for adequate estimation of a new cytostatic is selecting a primary dosage and its increase, selecting of the so-called "signal" tumors, elaborating the regimen of using the drug which agrees with the mechanism of its action and pharmacokinetics. The methods of randomization and stratification may be used for the third phase, but some elements of the latter are essential for the second phase to compensate the effect of different factors (age and general patients' status, the degree of proliferation and intensity of the process) on the results of chemotherapy. To compare the results of clinical trials, it is necessary to have a unified system of estimating the effectiveness of new chemotherapeutic antitumor drugs.