 Background: Drug-eluting stents have shown promising anti-restenotic effects in clinical trials. It may be preferable, however, to avoid the stent-in-stent approach in treating in-stent restenosis ISR. In prior animal trials, we demonstrated a highly significant reduction of neointimal formation by drug-eluting balloon catheters DEB. The aim of the PACCOCATH ISR study is to investigate the novel DEB in the treatment of ISR. 