Ultrasound controlled paclitaxel releasing system—A novel method for improving the availability of coronary artery drug coated balloon

Abstract

Objectives: The aim of this study is to improve local-drug delivery efficiency and tissue absorption using the ultrasound (US)-responsible drug coating based on a newly developed US-controlled paclitaxel release balloon. Background: Low availability of the drug coating remains a major concern of the current drug coated balloon (DCB). The goal of this study is to develop a method to use an US-responsible paclitaxel-loaded microcapsules (PM) as the main content of balloon drug coating to enhance bioavailability of DCB. Methods: An US-controlled paclitaxel release balloon is designed and fabricated based on the US-responsible paclitaxel-loaded poly (lactic-co-glycolic acid) (PLGA) microcapsules. Rapid exchange percutaneous transluminal coronary angioplasty (PTCA) balloon catheters were coated with the PM. The deployment processes of the paclitaxel-loaded microcapsules coated balloons (PMCB) under US, PMCB without US and a homogenous matrix of paclitaxel and iopromide coated balloon (PICB) were then placed in healthy and stent implanted porcine coronary arteries. Results: In vitro release assay demonstrated an ability of US (1 MHz, 1.22 W/cm2, 1 minute) to affect the release kinetics of paclitaxel from PM by inducing a 76 ± 5.4% increase in the rate of release. The paclitaxel content in target vessels are 203 ± 37 μg/g for PMCB under US, 85 ± 23 μg/g for PMCB without US, and 107 ± 31 μg/g for PICB 1-hr post-surgery. The availability of the drug for the PMCB reaches 27% under US. Conclusions: The US-controlled paclitaxel release balloon significantly improved the drug content of the target vessels in the porcine model.