Evaluation of Efficacy and Safety of Galantamine in Patients With Dementia of Alzheimer's Type Who Failed to Benefit From Donepezil

8 mg/day (4 mg twice daily) for 4 weeks, followed by 16 mg/day (8 mg twice daily) for an additional 4 weeks, followed by dose at 16 mg or increased to 24 mg (with the option of decreasing back to 16 mg) for the remainder of the study (to week 24)