erodible bioadhesive drug delivery vehicles for use in delivering pharmaceutical compounds to the eye and similar physiological environments are disclosed . the drug delivery vehicles are formed of a homopolymer or copolymer of maleic anhydride or lower alkyl maleic anhydride incorporating a pharmaceutical compound in either a monolithic matrix or encapsulated form . the bioadhesive erodible drug delivery vehicles are configured to be retained in the eye following administration while providing specific erosion profiles allowing convenient drug delivery schedules ranging from hourly to daily or weekly intervals .