Scientists begin phase 1 trial of a nasal vaccine for Alzheimer’s disease

nasal vaccine
A nasal vaccine for Alzheimer’s disease has been suggested based on research in mouse models. Will it, however, be viable in humans?
  • Alzheimer’s disease is one of the leading causes of death.
  • There is no recognized cure at this time.
  • Scientists have created a nasal vaccine that protects and treats mice with Alzheimer’s disease.
  • The vaccine is currently being tested in a small group of humans to evaluate if it is safe.

A new phase 1 trial for an Alzheimer’s disease nasal vaccination has begun. Scientists have successfully utilized the vaccine in mouse models that mimic some of the symptoms of Alzheimer’s disease.

If the latest trial demonstrates that the vaccine is safe in humans, more research will be done to see if it is also effective.

Alzheimer’s

Alzheimer’s disease is the most common type of dementia and a neurological disease.

Symptoms usually appear beyond the age of 60 in people who have the disease. Alzheimer’s disease is marked by a progressive loss of cognitive function, and in its most severe form, a person may be unable to respond to their surroundings.

Alzheimer’s disease is the sixth biggest cause of mortality among adults in the United States, with an expected 5.8 million people diagnosed in 2020.

There is presently no cure for Alzheimer’s disease, and most therapies aim to assist people manage their symptoms.

Is this a “remarkable milestone”?

Scientists at Boston’s Brigham and Women’s Hospital have begun a phase one clinical trial to evaluate if a potential treatment is safe for humans.

The team previously shown that the nasal vaccine might prevent and treat Alzheimer’s disease in a mouse model. These investigations were first published in 2005, then again in 2008, and then again in 2012.

“The beginning of the first human trial of a nasal vaccine for Alzheimer’s disease is a significant milestone,” says Dr. Howard L. Weiner, the study’s leader and co-director of the Ann Romney Center for Neurologic Diseases at the hospital.

“We’ve accumulated preclinical evidence demonstrating the possibility of this nasal vaccine for Alzheimer’s disease over the previous two decades.” If clinical trials in humans indicate that the vaccine is safe and efficient, it might be used as a nontoxic treatment for Alzheimer’s people, as well as given early to help prevent Alzheimer’s in people at risk, according to Dr. Weiner.

The adjuvant Protollin is used in the vaccine to boost the immune system. This has been proved to be safe in people when used in conjunction with other treatments.

The researchers expect that by activating white blood cells in lymph nodes in the neck, the vaccination will encourage these immune cells to eliminate beta amyloid plaques. These amyloid plaques, according to scientists, are a major cause of Alzheimer’s symptoms.

“This is a new path for the therapy of Alzheimer’s disease and other neurodegenerative disorders,” Dr. Oscar Lopez, director of the University of Pittsburgh’s Alzheimer’s Disease Research Center, told Medical News Today.

“This medication is particularly attractive for the treatment of Alzheimer’s disease because of the mode of action — immune system stimulation — and the nasal administration of the substance,” he stated.

“The researchers will begin a phase 1 trial, which is often used to assess the proper dosage and pharmacokinetics of drugs. If this is positive, they can continue forward with phase 2 and phase 3 studies to determine the treatment’s efficacy and safety.”

‘Very early days’

While the start of the phase 1 study is encouraging, there are still many obstacles to overcome before the vaccine can be proven to be a safe and effective treatment.

Prof. Tara Spires-Jones, personal chair of neurodegeneration at the University of Edinburgh and deputy director of the Centre for Discovery Brain Sciences, told MNT that there is a significant gap between mouse models and human participants: “We have a poor track record of translating from mice to humans in Alzheimer’s disease.” Mice don’t make ideal models.”

“This experiment comprises only 16 people, and it is primarily focused on safety,” she added. They’ve previously used a similar strategy in humans, so we know it’s safe in some populations.”

“However, in the experiment, they’re putting little amounts of this vaccine on people who are older and have symptomatic Alzheimer’s disease to ensure it’s safe for people with Alzheimer’s disease.” So it’s still early in the game.”

“If it’s safe for them, they’ll move on to the next stage of the experiment, when they’ll see if it’s effective.” So for the time being, it’s simply a test to see if this is really practical to use.”

Prof. Spires-Jones went on to say that the study had a sound rationale:

“In terms of scientific rationale, the idea that brain immune cells are involved in developing Alzheimer’s disease is strong. This particular approach is very general — it doesn’t target anything specific about Alzheimer’s — so whether this general boost in people will effectively combat Alzheimer’s disease is unknown.”

“In fact, it may go the opposite way,” she cautioned, “since we know that immune system cells are implicated in several ways at various phases of the disease.”

“So my takeaway from this is that it’s wonderful that things are moving forward, but you should be careful because it’s still early days, and we don’t know if it’ll even be safe, let alone effective.”

Approach and timing

Prof. Spires-Jones highlighted that the timing and strategy for targeting the immune response are critical.

“Immune cells are helpful in the brain in part because they remove diseases. Then, in part, they develop sick and poisonous, emit toxic substances, and cause inflammation,” she explained.

“However, the concern is that if you don’t target that immune response at the right moment in the disease process, or if you don’t execute it correctly, you could make things worse in the brain.”

Prof Spires-Jones told us, “There has also been a little bit of concern in the field that if you clean this amyloid protein out of the brain — especially if it’s wrapped around the blood vessels where they’ve degenerated — you could cause a little damage.” “I don’t think that’s the case because amyloid reduction is usually considered safe, so I wouldn’t be concerned.”

“However, this isn’t precisely amyloid decreasing — it’s blanket immune strengthening, and I’m not sure anyone understands if that’s a good thing yet.” However, it was beneficial to the mice.”

Prevent or treat?

According to Prof. Spires-Jones, the novel medication offers a higher chance of preventing Alzheimer’s disease than treating its symptoms.

“I believe this would be more effective in preventing rather than treating,” she added, “because our experience with everything that’s been tried to treat people who already have disorders has been dismal, at best.”

“It would be incredible if this worked. It would be the best possible outcome if we could prevent Alzheimer’s disease, and this would potentially be a safe method because the researchers suggest that this type of vaccine has been used in humans previously.”

“If it was safe and we could give it to everyone in their mid-60s who might be at risk, or who already have amyloid-positive symptoms, that would be a game-changer.” That, in my opinion, is more likely to work,” Prof. Spires-Jones added.

Changes in your way of life

Many cases of dementia, particularly Alzheimer’s disease, can be avoided by making lifestyle and behavioral adjustments, according to Prof. Spires-Jones, who believes that emphasizing this is critical.

“The most important takeaway message of any study like this is that we estimate that roughly 40% of all-cause dementia, of which Alzheimer’s accounts for about 60%, might be prevented by lifestyle, modifiable risk factors right now.”

“These are the same things you’d want to be doing anyhow to protect your heart and vascular system to minimize your risk of stroke and heart attack,” the researcher explained. Exercise, eating healthy foods, and remaining physically, mentally, and socially engaged are examples of these activities.”

“An unexpected [risk factor] is that hearing loss is linked to an increased chance of dementia — we don’t know whether this is causal or a result of the brain changes, but it certainly wouldn’t harm to get your hearing aids and wear them to stay stimulated.”

“This isn’t to say that lifestyle or behavioral adjustments will assist everyone,” she noted. 60 percent of dementia and Alzheimer’s disease [cases] are caused by genetic factors. So it’s not fair to hold dementia people responsible – some people are simply unlucky.”

“However, [important improvements] can avoid [the disease] and make a significant difference for some of us, so we should all take good care of ourselves.” This safeguards both our brain and the rest of our body.”