I had written previously about a potential Alzheimer’s disease vaccine that was quite exciting and potentially a “game changer” in the treatment of the disease. While researching that vaccine, I discovered several more Alzheimer’s disease vaccine candidates that were at various stages of development.

Even though most of these treatments are called vaccines, they are not for the prevention of the disease, they are used for the treatment of extant Alzheimer’s disease. It is an immunotherapy, much like treatments for cancer, in which the vaccine trains the immune system to attack the cancer. In the case of the Alzheimer’s disease vaccines, the immune system attacks one of the presumed biochemical causes of Alzheimer’s disease.

This article will discuss the key aspects of Alzheimer’s disease and how this vaccine can help treat it.

What is Alzheimer’s disease?

Before I proceed, it’s important to describe Alzheimer’s disease (AD). It is a chronic neurodegenerative disease that usually starts slowly and worsens over time. It accounts for 60-70% of dementia cases, even though the terms are sometimes used interchangeably. Alzheimer’s disease is a form of dementia.

Amyloid plaques (caused by amyloid beta, or Aβ), phosphorylated tau tangles (pTau), and neurofibrillary tangles are generally easily visible pathologies that can be observed by microscopic analysis of brain tissue from autopsies of those potentially afflicted by AD. These plaques and tangles seem to affect nerve functioning. Despite these observations, the precise pathophysiology, or development, of the disease is not known.

Since amyloid plaques are often identified in patients with Alzheimer’s disease, a large amount of research is focused on attacking those plaques as a way to reverse the effect on nerves which leads to AD.

The causes of AD are unknown (notice how much we do not know about this disease), although it is speculated that it is mostly genetically related, with a large number of genes that underlie this relationship. Despite the internet tropes, there is no rigorous evidence that aluminum causes AD – I wish this belief went away fast.

And since we have no clear understanding of the etiology and pathophysiology of AD, there are no treatments available today for the disease, though some drugs target the amyloid plaques but have not been shown to change the outcomes of AD.

There are a couple of medications that help manage some of the symptoms of the disease, but they are certainly not cures. There are several drugs at the very earliest stages of development that may hold out hope to treat the underlying disease.

One more thing that needs to be made clear. There are no biological tests for Alzheimer’s disease — usually, you can only find the amyloid plaques and other pathologies in post-mortem autopsies. Unfortunately. in the absence of an autopsy, clinical diagnoses of AD are “possible” or “probable”, based on other findings, such as memory tests and other methods.

List of Alzheimer’s disease vaccine candidates

Below is the list of Alzheimer’s disease vaccine candidates along with a link to any clinical trials:

• AC Immune — ACI-24.060 is an amyloid-beta (Abeta) antibody that attacks one of the causes of AD. It is designed to prevent Abeta plaque accumulation and enhance plaque clearance by generating antibodies against amyloid-beta and similar proteins. The vaccine candidate is in Phase 1 and 2 clinical trials.
• AC Immune and Janssen Pharmaceuticals — ACI-35.030 is an Alzheimer’s disease vaccine candidate designed to generate a specific antibody response against pTau proteins in the brain. The vaccine is undergoing Phase 1b/2a clinical trials in Europe. AC Immune has recently published results (these have not been published or peer-reviewed) that show that ACI-35.030 treatment rapidly leads to the strong and durable induction of antibodies specific for pathological forms of Tau, such as pTau. 
• Alzamend Neuro, Inc.’s — ALZN002 was developed to treat dementia-related Alzheimer’s disease. The vaccine candidate has completed a Phase 2A multiple ascending dose clinical trial. Another Phase 1/2A clinical trial is underway.
• Alzinova AB — ALZ101 is a therapeutic vaccine candidate that stimulates the production of antibodies against toxic amyloid beta oligomers.
• Vaxxinity — UB-311 is an immunotherapeutic vaccine candidate targeting toxic forms of aggregated amyloid-beta in the brain to treat Alzheimer’s disease. Phase 1, Phase 2a, and Phase 2a LTE trials have shown UB-311 to be highly immunogenic with a high responder rate and antibodies that bind to the amyloid beta target.

Summary of Alzheimer’s vaccine research

I was pleasantly surprised at how many different vaccines were under development to treat Alzheimer’s disease. I know that many of you have family members or know someone who has Alzheimer’s disease, and you would love to have access to these new vaccines.

Unfortunately, these are mostly in early development, and even though many of these vaccines have Fast Track designation by the FDA, which speeds up the development of novel treatments, it may be years before they are commercially available. However, as new clinical trials are set up by the sponsoring companies, individuals with Alzheimer’s disease may be able to volunteer for the clinical trial.

I am excited about these potential treatments for this insidious disease. However, I need to remind you that these vaccines target proteins that may or may not cause Alzheimer’s disease. They are a sign of the disease, but we just don’t have enough evidence to determine if they are the cause of it.

So, phase 3 clinical trials, which haven’t started for any of these vaccines, will need an endpoint of whether those vaccines actually reduce the symptoms of or reverses the disease itself. But for now, I am cautiously optimistic that we could have some effective treatments for Alzheimer’s disease. And that treatment could be a vaccine.

Citations

• Finder VH, Glockshuber R. Amyloid-beta aggregation. Neurodegener Dis. 2007;4(1):13-27. doi: 10.1159/000100355. PMID: 17429215.