Preliminary clinical experience with 4-epidoxorubicin in advanced human neoplasia

4'-Epidoxorubicin (epi-DXR) was tested in 56 patients with various types of advanced malignancies. The pattern of acute toxicity was similar to that of doxorubicin (DXR), but epi-DXR produced a lower incidence of vomiting, stomatitis, alopecia, and myelosuppression. The study of cardiac toxicity, utilizing only noninvasive methods, indicated that epi-DXR also is cardiotoxic. The increase in the systolic time intervals after the first dose as well as after cumulative doses was slightly lower compared with that observed after DXR. Antitumor activity occurred in a variety of tumors including malignant melanoma, renal cancer, and rectal cancer, which are refractory to DXR. Present results suggest that further studies with epi-DXR are indicated.