It's too early to say whether Targacept's drug will improve Alzheimer's treatment, but it has been given to 540 people in 12 prior trials for indications including mild cognitive impairment, which is often a precursor to Alzheimer's and age-associated memory impairment.

FORBES: Magazine Article

All three companies are also looking at whether their drugs work in a condition called mild cognitive impairment--mild memory loss that may or may not be a precursor to Alzheimer's or other dementia.

FORBES: Use Widening For Alzheimer's Drugs