Clinical evaluation of the cardiac toxicity of 4'-deoxy-doxorubicin

4'-deoxy-doxorubicin, a new doxorubicin analog, was tested in 65 phase II patients with advanced malignancies. Cardiac toxicity evaluation was performed by means of electrocardiography (ECG), left ventricular systolic time intervals, echocardiography and radionuclide left ventricular ejection fraction. ECG abnormalities were observed in a lower percentage of patients (23%) compared to that described for doxorubicin and other anthracycline analogs such as 4'-epi-doxorubicin and 4-demethoxy-daunorubicin. Other functional parameters serially measured to evaluate chronic cardiotoxicity in 23 patients, who received more than 200 mg/m2 were not significantly different from mean pretreatment values. No patient developed congestive heart failure but some of them exhibited a fall of left ventricular function parameters more than 15% from pretreatment values. These data suggest that this new analogue is probably less cardiotoxic than the parent compound doxorubicin but not completely devoid of cardiotoxicity.