The Connection Study is a six-month confirmatory Phase 3 study to determine the safety and efficacy of Dimebon in the treatment of mild-to-moderate Alzheimer's disease (AD).

This study is a randomized, placebo-controlled 6-month study designed as an adequate and well-controlled trial to demonstrate the safety and efficacy of Dimebon in the treatment of patients with mild-to-moderate AD. Dimebon is an investigational drug for Alzheimer's disease. The target of Dimebon's mechanism of action are the mitochondria (a cell's primary source of energy).The Connection Study is the second of two pivotal studies evaluating the effect of Dimebon. It is a 6-month study enrolling 525 patients in the United States, Europe, and South America. All patients completing the 6-month study will be eligible to receive Dimebon in an open-label extension trial.

The patient population will be carefully selected to ensure inclusion of patients with AD, rather than other types of dementia. Mild-to-moderate disease will be defined by the screening Mini-Mental State Examination (MMSE). Patients will attend study visits with caregivers who will provide information about the patient's condition.

Inclusion Criteria:

• Mild-to-Moderate Alzheimer's disease
• Probable AD (National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) and Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV)
• MMSE score 10-24 inclusive
• Computerized tomography (CT) san or magnetic resonance imaging (MRI) consistent with AD
• Caregiver who cares for the patient at least 5 days per week

Exclusion Criteria:

• Anti-dementia drugs including cholinesterase-inhibitors or N-methyl-D-aspartate receptor (NMDA) receptor antagonists within 90 days
• Other causes of dementia
• Other primary psychiatric or neurological disorders
• Unstable medical illnesses or significant hepatic or renal disease