FIELD: biotechnology. SUBSTANCE: recombinant factor VIII is prepared from mammalian cells by culturing in protein-free medium but with addition of polyol copolymers and in the presence of trace elements preferably, such as copper. Medium for preparing recombinant factor VIII contains polyglycol known as pluronic F-68, copper sulfate, chelate of iron sulfate with ethylenediaminetetraacetic acid and trace element salts, such as manganese, molybdenum, silicon, lithium and chrome. Method provides the enhancement of factor VIII formation and to reduce danger of its infection. EFFECT: improved preparing method. 13 cl, 3 tbl, 3 ex
