Enalapril Maleate and Doxorubicin Hydrochloride in Treating Women With Breast Cancer

This study is a drug interaction study designed to study the effects of enalapril on doxorubicin metabolism. Women with breast cancer for whom at least two cycles every 14 day doxorubicin is planned will be considered for enrollment. Study participation will be for 2 treatment cycles of doxorubicin or approximately 4 weeks. Patients will receive a 14 day course of daily enalapril in association with one cycle of doxorubicin and receive no study agent during the other cycle allowing patients to act as their own control. The sequence of enalapril dosing will be assigned by randomization at study enrollment. Blood samples for pharmacokinetics will be drawn before and at 7 time points after each of the two doses of doxorubicin. For each patient, serum doxorubicin and doxorubicinol concentrations both on and off of enalapril will be compared.