Aliphatic polyester terpolymers for stent coating and drug elution: effect of polymer composition on drug solubility and release

Drug Deliv. 2009 Aug;16(6):304-11. doi: 10.1080/10717540902999653.

Abstract

Ring-opening terpolymerization of L-lactide (LA), -caprolactone (CL), and glycolide (GA) was performed in the presence of tin (II) 2-ethylhexanoate at 170 degrees C. Random terpolyesters with weight-average molecular weight up to 130,000 g/mol were obtained. These terpolyesters, especially those with LA:CL:GA composition of 3:1:1, provided good coating integrity following spraying onto bare metal stents. The semi-synthetic macrolide immunosuppressant, everolimus, was incorporated into the terpolyester coating, and its release from the stent was evaluated. Unlike PLLA homopolymers, which are immiscible with the drug and non-optimal for controlled release, these terpolymers gave excellent control in a screening study, by tuning terpolymer molecular weight, relative monomer ratio, and drug-to-polymer ratio. Adjusting the polymer properties to improve drug solubility (or miscibility) in the polymer coating was found beneficial to the release profile.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Drug Delivery Systems / methods
  • Drug-Eluting Stents*
  • Polyesters / chemistry*
  • Polyesters / pharmacokinetics*
  • Polymers / chemistry*
  • Polymers / pharmacokinetics*
  • Solubility

Substances

  • Polyesters
  • Polymers