A new drug has been shown to slow brain shrinkage in multiple sclerosis patients, according to a new preliminary trial conducted in part with the University of Iowa.The study, published this week in the New England Journal of Medicine, tested a drug called ibudilast on individuals with progressive multiple sclerosis, a disease also commonly known as MS that affects the brain and central nervous system.Of the 255 patients with progressive multiple sclerosis, the study found that ibudilast slowed brain atrophy — or brain shrinkage — by 48 percent compared with the patients who took a placebo over the course of 96 weeks, said Dr.