Randomized Trial of Biolimus DCB for In-Stent Restenosis: The Primary Results of the REFORM Study

Background: In recent years, drug-coated balloon (DCB) angioplasty has become an established treatment option for the treatment of coronary in-stent restenosis (ISR). Objectives: The aim of this study was to compare the angiographic and clinical performance of the Biolimus A9–coated balloon (BCB; Biosensors Europe) with that of the paclitaxel-coated balloon (PCB; SeQuent Please, Braun Melsungen). Methods: REFORM (Prospective, Randomized, Non-Inferiority Trial to Determine the Safety and Efficacy of the Biolimus A9™ Drug Coated Balloon for the Treatment of In-Stent Restenosis: First-in-Man Trial) was a multicenter, assessor-blinded, noninferiority, 2:1 randomized controlled trial comparing the BCB and the PCB for the treatment of coronary ISR. The primary endpoint was in-segment percentage diameter stenosis at 6 months. Secondary endpoints included target lesion failure. The trial was registered prospectively at ClinicalTrials.gov (NCT04079192). Results: A total of 202 patients were randomized at 20 centers in 6 countries, with 135 in the BCB group and 67 in the PCB group. The mean patient age was 68.5 ± 10 years. At 6 months, in-segment percentage diameter stenosis was 43.3% ± 22.9% in the BCB group compared with 31.4% ± 17.7% in the PCB group (95% CI for the difference: 4.9%-18.8%; prespecified noninferiority margin 12%, noninferiority P = 0.48). At 1 year, target lesion failure was observed in 23.7% of patients in the BCB group vs 17.1% in the PCB group (HR: 1.44; 95% CI: 0.72-2.88; P = 0.28). Conclusions: In patients with ISR, the REFORM study failed to demonstrate noninferiority of the investigational biolimus DCB compared with the standard paclitaxel DCB.