Lyzed epimastigotes of Trypanosoma cruzi clones P209-1, Gamba1, Sp104-1, MASu, Y7/1, MN12, Cl-Brener, 86/2036, Y7/2-1 inhibit the growth of Ehrlich adenocarcinoma in mice. The tumor decreased 1.5-3 times after 12 daily injections of lysates from 15 million epimastigotes. The protective effect progressed after the injections were discontinued and depended on the dose and lysate producer clone. Trypanosoma lysates in the studied doses were nontoxic. © Springer Science+Business Media, Inc. 2006.