The invention relates to novel uses, pharmaceutical compositions and kits for use in medicine or for treating or preventing disease through the administration of random copolymers. The invention also relates to the treatment of autoimmune diseases, such as multiple sclerosis, and to the administration of random copolymers in treatment regimen comprising formulations that are administered at intervals greater than 24 hours, or to sustained release formulations which administer the copolymer over a period greater than 24 hours.