Biolimus A9™ (BA9™) Drug Coated Balloon (DCB) Study

Inclusion Criteria: * Patients presenting with in-stent restenosis (ISR) and clinical symptoms of ischemia and/or (i) evidence of ischemia on non-invasive testing or (ii) hemodynamically relevant lesion defined by FFR ≤ 0.80 or iFR ≤ 0.89 or \> 90% stenosis. * Patient presenting with a lesion that can be fully covered with one DCB length. - Patients can have up to two index lesions with ISR, which can both be treated and evaluated. * Patient has provided written informed consent * Age ≥ 18 years. * Patient is willing and able to comply with the study procedures and follow-up. Exclusion Criteria: * Patient presents with a ST-elevation myocardial infarction (STEMI) or had an acute MI within 48 hours prior to presentation (according to the universal definition of myocardial infarction). * Patient with acute cardiac decompensation or acute cardiogenic shock * Documented left ventricular ejection fraction (LVEF) ≤ 30% * Patient with impaired renal function (glomerular filtration rate \< 80 mL/min/1.73 m2). * More than 2 epicardial vessels requiring revascularization * Significant left main stenosis (by visual estimation) or an ISR located in the left main (LM). * Patient has an ISR lesion that cannot be covered with one DCB length. * Patient has an ISR in the target segment in a stent of a smaller diameter than 2.5mm. * Severe calcification that might prevent a sufficient expansion of the DCB, if not pre-treated with rotablation or a shockwave application device. * Known hypersensitivity or contraindication to biolimus, paclitaxcel, aspirin, thienopyridines, or iodinated contrast that cannot be pre-treated. * Pregnant and/or breast-feeding females or females who intend to become pregnant during the time of the study. * Subject currently enrolled in other investigational device or drug trial in which the primary endpoint has not yet been reached. * Anticipated difficulties to complete the angiographic follow-up study. * Patient with a life expectancy of less than 12 months. * Patients lacking mental capacity (i.e. patients suffering from dementia and others) to provide informed consent.