BIOGEN has recently announced the positive results of its trial of BIIB037 in Alzheimer’s Disease. The BIIB037 Phase Ib trial reported a significant decrease in beta amyloid and a significant reduction in cognitive decline compared to placebo. Alzheimer’s Disease is a chronic neurodegenerative disease that accounts for 60% of dementia cases in the USA. It is believed that this disease is associated with the buildup of beta amyloid plaques that tangle within the cortex of the brain, leading to the cognitive decline that characterizes dementia patients. Given the association between Alzheimer’s and beta amyloid protein, it is understandable that many pharmaceutical manufacturers have invested significant time and capital into discovering an effective therapy to target this protein.
In Alzheimer’s trials, tying reductions in beta amyloid plaques to improvement in cognitive function has proven incredibly difficult. ELI LILLY as well as PFIZER and J&J (in collaboration) have all ceased or delayed the FDA filing of their beta amyloid assets for this reason. The reduction in both beta amyloid protein and cognitive decline (as measured by the Mini Mental State Examination) achieved by BIIB037 is what sets this drug apart from those that have failed previously and could represent the first disease modifying drug for Alzheimer’s Disease. This trial result provides much-needed confidence to other manufacturers, especially those with beta amyloid targets. The history of failed trials in this space has led to many companies directing their attention away from Alzheimer’s.
In the US alone over 5.3 million people are thought to have Alzheimer’s Disease and while BIIB037 only targets mild to moderate forms of the disease, the potential for a blockbuster is evident. However, BIOGEN still has some significant safety and efficacy hurdles ahead. They must convert these exciting early stage results into solid Phase III data in a larger patient population while mitigating significant safety concerns; – something their competitors have struggled to accomplish. Should BIIB037 gain approval, the managed care world is sure to ask Biogen to concretely define the Alzheimer’s subpopulation that is most likely to respond to therapy, given the very large population that could be eligible for treatment and the likely high price tag associated with such an innovative launch. The ability for new drug intervention to slow the progression of this disease (and its associated healthcare expenditure impact) will remain a key question in coming years.