Background: Drug coated balloons (DCB) with paclitaxel (Ptx) dose of 2-3.5 μg/mm2 balloon surface inhibit restenosis with different effectiveness and duration of success. A clinical dose finding study is not known for any of the currently marketed products. The aim of the present preclinical trial was to investigate a novel DCB coated with 6 μg Ptx/mm2 in a porcine model.
Methods and results: The current study investigated a DCB with a novel, modified iopromide based matrix with 6 μg Ptx/mm2. Drug transfer to the vessel wall of peripheral arteries was compared with a dose of 3 μg Ptx/mm2 and two fully overlapping DCB with 3 μg Ptx/mm2, each. Ptx concentration in the vessel wall after drug transfer was about twice as high for balloons with 6 μg/mm2 (1957±1472 μg/g) and two overlapping DCB with 3 μg Ptx/mm2, each (1287±619 μg/g) compared to a single balloon with 3 μg Ptx/mm2, (787±738 μg/g), with statistical significant differences for 1x6 μg/mm2 vs. 1x3 μg/mm2 (p = 0.017) but not for 2x3 μg/mm2 vs. 1x3 μg/mm2 (p = 0.184) and 1x6 μg/mm2 vs. 2x3 μg/mm2 (p = 0.178). The proportion of residual Ptx on balloon after treatment was similar for all groups between 6±1% and 10±3% of dose on balloon.
Conclusion: The dose of 6 μg Ptx/mm2 was successfully as well as reproducibly coated on conventional balloon catheters. Increased Ptx on balloons resulted in increased drug concentration in the vessel wall. A single balloon with 6 μg Ptx/mm2 seems to provide double dose compared to 3 μg Ptx/mm2, facilitates the procedure, and may reduce medico-economic cost compared to the use of two standard DCB.