Researchers at Drexel University are studying an experimental medicine that they hope can stop Alzheimer's disease before it starts.

The drug solanezumab — from Eli Lilly -- clears away the amyloid plaque that builds up in the brain and destroys thinking and memory cells. But early studies found that "sola" did not help people who already have indications of Alzheimer's dementia.

Surgeon Erol Veznedaroglu, director of the Drexel Neurosciences Institute, said it's fair to say that those earlier attempts to treat mild and moderate Alzheimer's with sola failed.

"It's too late, there's really nothing we can do to reverse it once it occurs," he said.

In the newest arm of the study, the latest approach is to give the plaque-clearing drug to healthy people who have a high risk for dementia but before they have signs of Alzheimer's.

Study participants will take the drug for years to come, and health investigators will watch for signs of problems with thinking or memory.

"This is the first really big study — we call it a disease-modifying study — that could actually affect the biology of the disease to prevent it, or at least delay the onset of the disease," said neurologist Carol Lippa. She runs the cognitive and memory disorders program at Drexel University College of Medicine.

Drug maker Eli Lilly and the federal government are funding the study.

The Drexel site is one of 60 locations across the United States, in London and Canada looking for healthy volunteers age 65 and older.

Alzheimer's is the sixth-leading cause of death in the United States.

With no cure, about 5 million people in the U.S. are living with the disease, and as baby boomers age that number is expected to rise dramatically.

To find a research site location or information on eligibility, visit the A4study Web site.