A Phase 3 multi-center trial, 12 month safety and efficacy study evaluating an oral study medication in patients with mild to moderate Alzheimer’s disease. Over 1000 patients enrolled across 120+ sites in 10 countries worldwide with approximately 60 sites in the United States. Patients will be followed for 12 months of study treatment and offered open label study drug at the end of that time for a period of at least one year after which minimal evaluations will be required and patients will be followed for safety.