Rosiglitazone (Extended Release Tablets) As Adjunctive Therapy In Subjects With Mild To Moderate Alzheimer's Disease

Rosiglitazone (RSG) has been tested in clinical studies and is approved by the FDA as a treatment for type II diabetes mellitus, a disease that occurs when the body is unable to effectively use glucose. RSG XR, the investigational drug used in this study, is an extended-release form of RSG. This study tests whether RSG XR safely provides clinical benefit to people with mild to moderate Alzheimer's disease (AD) when combined with one of the currently approved AD medications, Aricept®, Razadyne® or Exelon®. RSG XR is a new approach to AD therapy and this study tests a new way to treat AD by testing whether one's genetic makeup affects the response to the study drug. Clinical data suggesting that RSG may benefit AD patients was first seen in a small study performed at the University of Washington and then from a larger GSK study conducted in Europe and New Zealand. In the first study, subjects receiving RSG once daily for 6 months scored significantly better on 3 tests of memory and thought than those who did not receive RSG. In the GSK study, those that appeared to benefit most from treatment with RSG XR had a specific genetic pattern. They did not have the gene that caused them to produce the protein apolipoprotein E e4 (APOE e4). Subjects who have the APOE e4 gene may have two copies, one from each parent, or they may have only one APOE e4 gene meaning that they inherited either the APOE e2 or APOE e3 version of the gene, instead of APOE e4, from one of their parents. Subjects with one copy of the APOE e4 gene remained at their same level of thinking ability while those with two copies of the APOE e4 gene, continued to worsen during the 6-month treatment. The current study will more directly test the effectiveness or RSG XR on people who either have or lack the APOE e4 gene.