A closely watched experimental Alzheimer's treatment has failed to slow the disease in one late-stage study, a big disappointment for doctors and patients but not the end of the road for the drug. Pfizer Inc. said Monday that it will continue to study its effect on a different group of patients…Biomarkers are genes or measurable characteristics that indicate a normal biologic process, a disease or a response to a treatment. "I would defer complete judgment on the drug until I see some biomarker data," said Dr. Ronald Petersen, director of the Mayo Clinic's Alzheimer's Disease Research Center. "It still may leave the door open for some positive news if there are any biomarker movements."
AP by Linda Johnson