The invention relates to pharmaceutical compositions comprising an ester ofolmesartan, such as olmesartan medoxomil. Olmesartan medoxomil is a prodrugthatis hydrolyzed during absorption, but it is not desirable that it hydrolyzesprior toingestion, during storage. A stable formulation comprising an ester ofolmesartan andstearic acid, exhibiting exceptional stability when subject to stressconditions, isdisclosed. Processes for the preparation of such pharmaceutical compositions,aswell as the use of stearic acid to prevent degradation of olmesartanmedoxornil toolmesartan acid in a pharmaceutical composition, are also disclosed.
