Abstract Body (Do not enter title and authors here): Background:
Internationally, drug-coated balloons have emerged as a new treatment approach in In-Stent Restenosis (ISR) offering localized drug delivery to inhibit neointimal growth without the need for additional stent layers. However, their use has not been assessed or approved in the United States. Paclitaxel-coated balloons (PCBs) are gaining traction as alternatives for in-stent restenosis patients. Yet, their safety and effectiveness compared to uncoated balloons remain uncertain. This meta-analysis seeks to systematically assess PCBs' safety and efficacy for ISR treatment by comparing them to uncoated balloons.

Research Question:
Are paclitaxel-coated balloons (PCBs) superior to uncoated balloons (UCBs) in terms of safety and efficacy for the treatment of coronary in-stent restenosis (ISR)?

Aims:
Systematically assess the safety and efficacy of paclitaxel-coated balloons (PCBs) compared to uncoated balloons (UCBs) for the treatment of coronary in-stent restenosis (ISR).

Methods:
A comprehensive literature review was conducted utilizing multiple databases up to May 2024, focusing on randomized controlled trials comparing PCB vs UCB in patients with coronary in-stent restenosis. Six randomized controlled trials with a total of 1,347 patients who completed 1-year follow-up were included. Dichotomous data were calculated as odds ratios (ORs) and 95% confidence intervals (95% CI). P<0.05 was considered to indicate a statistically significant difference. The primary outcomes included Target Lesion Revascularization (TLR), Myocardial Infarction (MI), Stent Thrombosis (ST) and Total Mortality (TM).

Results:
Compared with patients who underwent UCB angioplasty, those in the PCB group exhibited a clear superiority in TLR [odds ratio (OR), 0.21; 95% CI [ 0.11,0.41]; P<0.00001], and MI [odds ratio (OR), 0.55; 95% CI [0.33,0.91]; P<0.02]. ST was numerically lower in the PCB arm without statistical significance (OR, 0.21; 95% CI [0.03,1.48]; P=0.11). TM was also numerically lower with PCB without reaching statistical significance (OR, 0.60; 95% CI [0.32,1.11]; P=0.10).

Conclusion:
This meta analysis supports that PCBs are associated with superior outcomes when compared with UCBs in the management of ISR. Paclitaxel-coated balloons are an effective treatment option for patients with coronary in-stent restenosis as demonstrated by superior outcomes in target lesion revascularization and recurrent myocardial infarction.