Microencapsulated 3-piperidinyl-substituted 1,2-benzisoxazoles and 1,2-benzisothiazoles

A sustained-release microparticle comprising:

• a 1,2-benzazole of the formula ##STR16## and the pharmaceutically acceptable acid addition salts thereof, wherein R is hydrogen or alkyl of 1 to 6 carbon atoms;
• R.sup.1 and R.sup.2 are independently selected from the group consisting of hydrogen, halo, hydroxy, alkyloxy of 1 to 6 carbon atoms, and C alkyl of 1 to 6 carbon atoms;
• X is O or S;
• Alk is C.sub.1-4 alkanediyl;
• and
• Q is a radical of formula ##STR17## wherein R.sup.3 is hydrogen or alkyl of 1 to 6 carbon atoms;
• Z is --S--, --CH.sub.2 --, or --CR.sup.4 .dbd.CR.sup.5 --;
• where R.sup.4 and R.sup.5 are independently selected from the group consisting of hydrogen or alkyl of 1 to 6 carbon atoms;
• A is a bivalent radical --CH.sub.2 --CH.sub.2 --, --CH.sub.2 --CH.sub.2 --CH.sub.2 -- or CR.sup.6 .dbd.CR.sup.7 --;
• where R.sup.6 and R.sup.7 are independently selected from the group consisting of hydrogen, halo, amino or alkyl of 1 to 6 carbon atoms;
• and
• R.sup.8 is hydrogen or hydroxyl;
• and a biodegradable and biocompatible polymeric matrix.