BACKGROUNDIn-stent restenosis caused by airway granulation poses a challenge due to the high incidence of recurrence after treatment. Weekly applications of anti-proliferative drugs have potential value in delaying the recurrence of airway obstruction. However, it is not practical to subject patients to repeated bronchoscopy and topical drug applications. We fabricated novel pacilitaxel-eluting tracheal stents with sustained and slow pacilitaxel release, which could inhibit the formation of granulation tissue. And we assessed the quality and drug release behaviors of drug-eluting stents (DESs) in vitro.

METHODSStents were dipped vertically into a coating solution prepared by dissolving 0.5 g (2% w/v) of poly lactic acid-coglycolic acid (PLGA) and 0.025 g (0.1% w/v) of pacilitaxel in 25 ml of dichloromethane. DES morphology was examined by scanning electron microscopy (SEM). Pacilitaxel release kinetics from these DESs was investigated in vitro by shaking in PBS buffer followed by high performance liquid chromatography (HPLC).

RESULTSUsing an orthogonal experimental design, we fabricated numerous pacilitaxel/PLGA eluting tracheal stents to assess optimum coating proportions. The optimum coating proportion was 0.1% (w/v) pacilitaxel and 2% (w/v) PLGA, which resulted in total pacilitaxel loading of (16.380 6 ± 0.002 1) mg/stent. By SEM the coating was very smooth and uniform. Pacilitaxel released from DES was at (0.376 3 ± 0.003 8) mg/d, which is a therapeutic level. There was a prolonged, sustained release of pacilitaxel of >40 days.

CONCLUSIONSPaclitaxel-loaded PLGA coating tracheal stents were successfully developed and evaluated. Quality assessments demonstrated favorable surface morphology as well as sustained and effective drug release behavior, which provides an experimental reference for clinical practitioners.