Fifteen patients with hormone resistant advanced prostate cancer were treated with anthracycline analog 4'-deoxydoxorubicin (Esorubicin). No patient had objective evidence of tumor regression. Six patients (40%) were classified using the National Prostatic Cancer Project criteria as having stable disease after two courses of therapy. Treatment was associated with significant hematologic toxicity with 50% of patients experiencing grade III or IV neutropenia. Clinical cardiac toxicity was not observed. Further trials of 4'-deoxydoxorubicin do not appear to be warranted in advanced prostate cancer.