Alzheimer's disease is the leading cause of dementia in the United States today. It devastates families, leaving in its wake fear, sadness, and confusion. Since it cannot be fully diagnosed until after it has caused death, Alzheimer's hangs over the heads of many Americans. The symptoms of this harrowing disease include but are not limited to memory loss, balance control issues, confusion, aggression, and wandering. (However, these symptoms may be due to other causes as well.) For caregivers of someone with symptoms and a diagnosis of Alzheimer's, the crucial question is the possibility of a cure. As of yet, there exists no cure for Alzheimer's disease; however, scientists have found new drugs that show some promise.
Recently, a team from Merck (a pharmaceutical organization) released a new study that shows progress on an Alzheimer's cure. In scientific terms, the researchers used a BACE1 inhibitor to slow (or perhaps even stop) the progression of Alzheimer's disease. This type of medication blocks the ability of the enzyme beta-secretase 1 to produce amyloid beta. Amyloid beta forms clumps in the brain.
It is these clumps which form plaques and surround neurons in the brain, causing Alzheimer's disease. When neurons are blocked from sending signals, parts of the brain cease to be able to communicate. This creates the well-known symptom of memory loss, since memory-holding parts of the brain can no longer communicate with the rest of the brain. This is why it is possible, for example, for an Alzheimer's patient to forget routes he or she knows well. The memory of the streets and turns are present; there is simply a blotting out of communication within the brain. An Alzheimer's patient may forget how to get around an open door, or how to navigate a flight of stairs. The almost automatic messaging of the brain has been interrupted by neuron-blocking deposits and tangles.
If the Merck researchers' hypothesis is correct, then a medication that blocks production of amyloid beta would, indeed, halt Alzheimer's.
It should be made perfectly clear: this study has not reached a stage where it can declare a definitive cure or stop to Alzheimer's disease. Many other attempts have been or are being made to do just what Merck has done. However, they have encountered numerous roadblocks. The most significant obstacle is side effects. One molecule in the drug does that is needed but may cause side effects like liver toxicity. Studies had to be cut short in order to keep patients safe. This left the researchers wondering whether the drugs really had any impact on Alzheimer's disease. The studies stopped too soon to tell. What evidence has been released from Merck shows promise, however, in its short, limited trials. The drug, called verubecestat, showed some promise in adults with mild to moderate forms of Alzheimer's disease.
Initial results show that side effects from the new drug are, thus far, nonexistent. Those few people taking part in the clinical trial did not experience the dangerous side effects caused by other drugs. This development means that Merck can move on to more extensive human trials. While the drug is some time away from being available on the market, it is certainly making headway in the world of research for a cure for Alzheimer's.
The most important takeaway is likely this: given these promising results, the drug can now move to full clinical trials. That does not mean that the drug is perfect, though. Since the drug only prevents (in theory) the production of new clumps that obstruct neurological activity, later-stage patients may not be helped by it. The drug likely cannot remove existing plaque and give late-stage Alzheimer's patients their memories and lives back. It can, however, be implemented in early-stage patients in order to prevent further decline. For Alzheimer's patients, that could mean being on medication for the rest of their lives. It is important, then, to impress upon caregivers for Alzheimer's patients the need for quality health insurance. Public advocacy, too, should include low drug costs for seniors with low incomes.
Caregivers of seniors who have Alzheimer's disease should consider speaking with a doctor about testing, preventive measures, and even enrollment in clinical trials. The new Merck drug is, at this time, a ray of hope for caregivers of Alzheimer's patients and their charges.
Kennedy, Matthew E., Stamford, Andrew W., Chen, Xia, Cox, Kathleen, Cumming, Jared N., Dockendorf, Marissa F., et al. (November 2, 2016). The BACE1 inhibitor verubecestat (MK-8931) reduces CNS b-amyloid in animal models and in Alzheimer's disease patients. Science Translational Medicine, 8(363): pp. 363ra150. Available at http://stm.sciencemag.org/content/8/363/363ra150. Retrieved November 19, 2016.
Makin, Simon. (November 2, 2016). New Alzheimer's Drug Clears Milestone in Human Clinical Trial. Scientific American. Available at https://www.scientificamerican.com/article/new-alzheimer-s-drug-clears-milestone-in-human-clinical-trial1/#. Retrieved November 19, 2016.