A modified release pharmaceutical composition comprising, as active ingredient, a compound of formula (I), wherein R.sub.1 represents C?1-2#191 alkyl substituted by one or more fluoro substituents; R.sub.2 represents hydrogen, hydroxy, methoxy or ethoxy; and n represents 0, 1 or 2; or a pharmaceutically acceptable salt thereof; and a pharmaceutically acceptable diluent or carrier, provided that the formulation may only contain iota-carrageenan and a neutral gelling polymer when the compound of formula (I) is in the form of a salt; such formulations being of use for the treatment of a cardiovascular disorder ##STR00001##