Controlled release pharmaceutical compositions comprising a fumaric acid ester

A controlled release capsule comprising one or more enteric coating polymers forming an outermost coating of the capsule, wherein the capsule contains coated micro-crystals, wherein the coated micro-crystals comprise

• as an active substance from 10% to 90% w/w of a fumaric acid ester selected from the group consisting of a di-(C1-C5)alkylester of fumaric acid, a mono-(C1-C5)alkylester of fumaric acid, and a pharmaceutically acceptable salt thereof;
• ethyl cellulose;
• a hydrophilic excipient;
• wherein the fumaric acid ester is in the form of micro-crystals, the ethyl cellulose and hydrophilic excipient are present in a coating on the micro-crystals, the ethyl cellulose is 10% to 50% w/w of the coated micro-crystals, and wherein the release of the fumaric acid ester—when subjected to an in vitro dissolution test employing 0.1 N hydrochloric acid as dissolution medium during the first 2 hours of the test and then 0.05 M phosphate buffer pH 6.5 as dissolution medium—is as follows:
• within the first 3 hours after start of the test from 15% to 50% w/w of the total amount of the fumaric acid ester contained in the capsule is released.