The present invention relates to biomedically useful compositions of C2-C3 linked polyethers of 1,6:2,3-dianhydrohexopyranose derivatives combined with effective amounts of one or more bioactive agents. In certain embodiments the C2-C3 linked polyether of a 1,6:2,3-dianhydrohexopyranose derivatives are aqueous insoluble. In certain other embodiments biomedically useful compositions have the physical form of microparticles, microspheres, tubes, rods, sheets, membranes, fibers and the like. In certain embodiments the bioactive agent is a protein.