Drug delivery from stents

A method for producing a drug coated intravascular stent comprising the steps:

• a) coating a metallic stent body on its inner and outer walls with a cross-linkable amphiphilic polymer;
• b) subjecting the cross-linkable amphiphilic polymer to conditions under which cross-linking takes place to produce a polymer-coated stent;
• c) contacting at least the outer coated wall of the polymer coated stent with a liquid drug composition comprising a sparingly water-soluble matrix metalloproteinase inhibitor (MMPI) and an organic solvent in which the MMPI is at least partially dissolved and which is capable of swelling the cross-linked polymer of the coating, for a time sufficient to swell the polymer coating on the outer wall, to produce a wet drug-coated stent;
• and
• d) evaporating the organic solvent from the wet drug-coated stent to produce a dry drug-coated stent;
• wherein the cross-linkable amphiphilic polymer is of formula:
• wherein:
• B is a straight or branched alkylene, alkyleneoxaalkylene or alkylene oligo-oxaalkylene chain optionally containing one or more fluorine atoms or, if X contains a terminal carbon atom bonded to B, a valence bond;
• X is a zwitterionic group;
• A is —O— or —NR1—;
• A1 is —O— or —NR15—;
• A2 is —O— or —NR22—;
• B2 is a straight or branched alkylene, oxaalkylene or oligo-oxaalkylene chain optionally containing one or more fluorine atoms up to and including perfluorinated chains, or B2 is a valence bond;
• D is a non-ionic alkyl(alk)acrylate or hydroxyalkyl(alk)acrylate;
• R is hydrogen or a C1-C4 alkyl group;
• R1 is hydrogen or a C1-C4 alkyl group or R1 is —B—X;
• R13 is a straight or branched alkyl, alkoxyalkyl or oligoalkoxyalkyl chain containing four or more carbon atoms unsubstituted or substituted by one or more fluorine atoms optionally containing one or more carbon double or triple bonds, or —(CR182)qq(SiR192)(OSiR182)ppR19;
• R14 is hydrogen or a C1-C4 alkyl group;
• R15 is hydrogen, a C1-C4 alkyl group or R13;
• each R18 is the same or different and is hydrogen or alkyl of 1 to 4 carbon atoms, or aralkyl;
• each R19 is alkyl of 1 to 4 carbon atoms;
• R20 is selected from the group consisting of ethylenically and acetylenically unsaturated group containing radicals;
• aldehyde groups;
• silane and siloxane groups containing one or more substituents selected from halogen atoms and C1-4-alkoxy groups;
• hydroxyl;
• amino;
• carboxyl;
• epoxy;
• —CHOHCH2Hal;
• succinimido;
• tosylate;
• triflate;
• imidazole carbonyl amino;
• optionally substituted triazine groups;
• acetoxy;
• mesylate;
• carbonyl di(cyclo)alkyl carbodiimidoyl;
• isocyanate, acetoacetoxy;
• and oximino;
• R21 is hydrogen or C1-4 alkyl;
• R22 is hydrogen, a C1-C4 alkyl group, or B2R20;
• Hal is selected from chlorine, bromine and iodine atoms;
• qq is from 1 to 6;
• pp is from 0 to 49;
• l is 1 to 75;
• m is 0 to 99;
• n is 0 to 33;
• i is about 15;
• and
• n+m is 25 to 99.