Alzheimer’s Disease is an asteroid headed directly at Earth. An astonishing 1 in 4 Americans are expected to develop this devastating disease during their lifetimes, and its a horror story of a disease, with people losing their ability to even recognize themselves long before death essentially comes as a blessed relief.
Of course, like all horror stories, there is no current hope: No drug works to even marginally improve, much less cure or prevent, the disease. And much like the self-interested, long unrequited hype generated around HIV vaccines, cancer and gene therapy, every month over the past many years brings a “new breakthrough drug” for Alzheimer’s, and none–not a single one–has actually modified the disease in any way.
Throw enough darts at the board though and one eventually hits. But was it by chance or was the aim finally good? Such is the case with Biogen’s aducanumab, which failed its primary endpoints in two large trials (EMERGE and ENGAGE), on the heels of 20 years of failure of all similar amyloid-targeted therapies, but then, on reanalysis, a hint of a signal was seen. Basically, in a subset of people who got higher doses of the drug, the first ever statistically significant improvement in an Alzheimer’s symptom was detected.
As background, Alzheimer’s disease has long been pathologically characterized by the deposition of “amyloid-beta” or Abeta plaques in brain tissue, with more deposits being characteristic of more severe disease. Physicians and scientists have long debated whether Abeta is reactive or causative in Alzheimer’s, but its specificity for the disease and correlation with disease progression led to enormous efforts to combat it. Unfortunately, in a “proof-is-in-the-pudding” evolution, the “reactive” camp has been bolstered by the uniform clinical trial failure of every single Abeta-targeted drug developed. So the party line was that Abeta was reactive and it was time to move on before Biogen crashed the party last year.
Nevertheless, the news has made a huge splash throughout the field and even across the entire pharmaceutical industry. Many big companies were getting out of the Alzheimer’s game recently, due to the lack of hope. Now a watershed time has come and everyone has to choose sides. Whichever side the FDA comes down on, there is going to be a huge reaction. Welcome to 2020, FDA!