Epipodophyllotoxin (VM 26; 4′-demethyl-epipodophyllotoxin-β-D-thenylidene glucoside) has been proved, in clinical screening, to be able to induce apparently complete remissions and pronounced though incomplete regressions in Hodgkin's disease, reticulosarcoma, and bladder cancer, as well as incomplete regressions in lymphosarcoma. Apparently complete regressions of malignant pleural effusions have been obtained after giving this drug systemically. It has a notable toxic action on the bone marrow.