The present invention relates to a composition-eluting balloon catheter (100) having a proximal (20) and distal (15) end, comprising an elongated catheter tube (6) with an inflation lumen (7) extending therewithin and at least one inflatable balloon (4) towards the distal end (15) in fluid communication with the inflation lumen (7), wherein the balloon (4) in the uninflated condition is provided as one or a plurality of folded wings (10′, 10″), and composition (12′, 12″) is provided essentially exclusively within the folds of the wings (10′, 10″), wherein the balloon (4) in the uninflated condition is further provided with a relief structure (30) comprising at least one groove on the outside of the folded wings (10′, 10″), configured to substantially reduce in depth in an inflated state of the balloon (4), and whereby the at least one groove is essentially devoid of composition (12′, 12″).
