FIELD: organic chemistry, pharmacy.
SUBSTANCE: invention relates to a method for preparing a liquid antitumor composition containing derivative of camptothecin. Derivative is prepared by binding compound of the formula (I): 
with polysaccharide having carboxyl groups through amino acid or peptide, and pH value of composition is brought about to 5-8 using a buffer. As a buffer method involves using one or more compounds chosen from group consisting of citric acid, alkaline metal citrate, acetic acid, alkaline metal acetate and alkaline metal dihydrophosphate that provides the excellent stability of composition at storage being not only as a lyophilizate but as a solution also.
EFFECT: improved and valuable pharmaceutical properties of preparation.
17 cl, 6 tbl, 5 ex
