Doxorubicin With or Without Sildenafil, With Analysis of Cardiac Markers

Definitive study of sildenafil enhancement of anthracycline anticancer effects and cardioprotection would require a randomized, placebo-controlled trial involving large numbers of patients and many years of follow-up. It is appropriate to demonstrate that concurrent administration of sildenafil and doxorubicin is safe and tolerable. Second, in definitive studies it might be helpful to incorporate early markers of cardiac injury in order to gain early insight into cardioprotective effects, but there are no such established markers. As a correlative study, multiple intermediate markers will be tested. In order to investigate these candidate markers it is appropriate to study patients receiving doxorubicin alone, as early markers of injury may not be apparent in patients treated with the combination. In order to accomplish these two goals the trial is a randomized trial involving a sildenafil/doxorubicin group and a doxorubicin group.