Despite all the excitement over Biogen's ($BIIB) recent Phase I success in Alzheimer's, the question of whether attacking protein buildups in the brain can in fact treat the disease remains a subject of intense debate in the neurology world. And Roche ($RHHBY), at work on a $100 million trial, is out to find out once and for all. The Wall Street Journal takes a detailed look into the company's expansive effort to determine whether crenezumab, a beta amyloid-targeting antibody, can slow the progression of early-onset Alzheimer's in patients genetically predisposed to the disease. Roche has zeroed in on a region in Colombia with a particularly high concentration of such patients, finding an ideal proving ground for its treatment. Thanks to the purity of the population, some researchers say the crenezumab could provide the final word on the amyloid hypothesis once final results are available in 2020. More