(Post by Cameron Jahansouz, 2L at Stanford Law School)
In a rather over-the-top fashion, the Dean of Case Western School of Medicine announced “breaking news” regarding “a dramatic breakthrough in the battle against Alzheimer’s disease.” Professor Gary Landreth and his team of neuroscientists have discovered that administration of the cancer drug bexarotene in mice trials resulted in a 25% reduction of soluble amyloid beta plaque levels after just 6 hours. After 72 hours, bexarotene treatment cleared over 50% of the plaques en route to a final clearance level of 75%. Remarkably, the reduction of soluble and deposited amyloid plaque levels was met by the return of cognitive and memory deficits. Further, bexarotene improved mice ability to detect and respond to odors. Comparably, first author Paige Cramer noted that “the best existing treatment for Alzheimer’s disease in mice required several months to reduce plaque in the brain.” The drug works by stimulating retinoid X receptors, which are directly responsible for moderating Apolipoprotein E (ApoE) production. By augmenting the production of ApoE, which acts to remove amyloid beta naturally from the brain, the drug presents an innovative approach which huge potential implications.
So, where do we go from here?
For the moment, we will have to wait and see. The success has only been evident in mice trials. Needless to say, treatment of Alzheimer’s disease in mice does not represent a perfect analog to the treatment of the disease in humans. Nor is the Alzheimer’s disease used in mice the same as that found in humans. Further, it goes without saying that mice trials do not always segue with 100% reliability to human trials. This is true especially in the case of Alzheimer’s drugs, such as Dimebon, that have made their way into clinical trials and failed to demonstrate effectiveness.
Though this is an important advancement, it is way too early to pop open the champagne and declare the end of Alzheimer’s. There is no guarantee that bexarotene will work as effectively once clinical trials are performed. Indeed, it may just be yet another disappointing end in a long line of hopeful beginnings.
Depending on your perspective, the larger concern is that, as bexarotene is FDA-approved for a form of skin cancer known as cutaneous T-cell lymphoma, doctors will be able to prescribe bexarotene for off-label usage without technically needing to go through IRB approval. As a result, patients would not need to make an Abigail Alliance argument to gain access to bexarotene as soon as possible. This is a dangerous proposition for obvious reasons. A desperate patient would only need to find a willing doctor to provide the untested drug, and he or she would be free to do so without falling into the FDA’s jurisdiction.
Here is the link to the press release: