There is a great deal of research being conducted in the area of cell structure and the treatment of Marfan syndrome. In 2006, research found that a drug commonly used to lower blood pressure may help individuals with Marfan syndrome. Studies indicated that the drug losartan stopped aortic enlargement and reversed muscle wasting in genetically engineered mice with Marfan. The mice who received losartan developed a stronger aorta and had a lower risk of aortic aneurysm (bursting of the artery). Clinical trials are underway to test the effectiveness of this drug in people with Marfan syndrome. Other clinical studies are also comparing losartan to another drug atenolol to determine which one is more effective in slowing aortic growth. In addition, the trials are studying the side effects that may occur with either drug.