A two-layer dissolution-diffusion model is derived which incorporates a surface burst component that is estimated from continuum percolation models of overlapping Poisson distributed spheres. The model is shown to adequately describe the release properties of paclitaxel from a hydrophobic polymer matrix, including the surface burst and sustained release dependence on drug loading.

The ultimate test for implant biomaterials is determined by the long-term, post-market clinical product performance. This is a key consideration in the initial design and development for drug-eluting stents. To insure this ultimate clinical success, a rigorous series of bench-top, preclinical and clinical evaluations must be performed. The factors in the biomaterial choice which are important for each stage in this development process include pharmaceutical, physical, and biological elements. This presentation will outline the steps taken by Boston Scientific in each of these stages to achieve the desired clinical end-points.