In 1993, Harvard researchers Dennis Selkoe and Howard Weiner got together over dinner to talk about how they might combine their expertise to find a better treatment for Alzheimer’s, a disease that robs more than 4 million Americans of their cognition and personalities. Selkoe has spent much of his research career trying to understand how Alzheimer’s destroys a person’s brain. For the past 15 years, Weiner has been developing oral and nasal vaccines for diseases such as multiple sclerosis, rheumatoid arthritis, and diabetes. They decided to fight Alzheimer’s with the same protein that seems to cause it. Now they have successfully treated Alzheimer’s disease in mice by putting drops of vaccine in their noses. They think it will ultimately be possible to do the same with people.”We plan to begin human trials next year,” in 2002, says Weiner. “These studies open up the possibility, not only of treating Alzheimer’s, but of preventing it by injection or nasal spray,” says Selkoe.