Scientists hope jab could be available for patients within the next four years.
BRATISLAVIA, Slovak Republic — For people genetically prone to developing Alzheimer’s disease, the fear of one day becoming unaware of who and where they are can be a frightening thought. Perhaps even worse is knowing the burden the mind-erasing condition puts on loved ones. Though there is no cure for the disease, scientists believe they are on the cusp of creating a safe Alzheimer’s “vaccine” that slows and may even prevent the condition entirely.
According to researchers with Axon Neuroscience, their trial shows the Alzheimer’s vaccine, dubbed “AADvac1,” reduced mental deterioration by almost a third. It works by priming the immune system to kill rogue tau proteins, the well-known signature of the disease. Tau clump together in “tangles” inside brain cells, leading to the memory-robbing illness.
“The accumulation and spread of toxic forms of tau in the brain is a pathological hallmark of Alzheimer’s. It is thought to be responsible for the widespread death of neurons that ultimately leads to dementia,” explains corresponding author Dr. Petr Novak, per South West News Service.
Novak describes the antibody response to tau as “exceptional.” His team’s Alzheimer’s vaccine slashed clinical and functional decline by 27 and 30 percent, respectively.
“This is especially important when treating the elderly,” he says. “These tangles disrupt the normal functioning of neurons and were identified as one of the primary reasons for cognitive impairment in people with Alzheimer’s.”
Blood levels of a protein known as NfL (Neurofilament Light Chain), which is released by damaged brain cells, plunged by up to 62 percent. This was supported by strong reduction of core Alzheimer’s disease CSF (cerebrospinal fluid) biomarkers of neuro-degeneration. They include the most specific hallmark of the disease known as phospho-tau T217.
“The most pronounced effects of the vaccine were observed in a subgroup of patients with confirmed Alzheimer’s,” says Novak.
The 109 participants had undergone MRI brain scans to confirm Alzheimer’s. “In this subgroup, AADvac1 in comparison to a placebo significantly slowed the clinical decline by 27 percent and functional decline by 30 percent.”
Alzheimer’s vaccine could outperform latest therapy approved to treat patients
It opens the door to treating and possibly preventing tau pathology, the “driving force behind the clinical decline of patients,” says Novak.
The international team believes AADvac1 is even better than Aducanumab, which just became the first new Alzheimer’s drug to be approved in nearly 20 years. It removes sticky deposits of amyloid beta proteins, which also gather in the brains of patients.
“The recent approval of an amyloid-based therapy was encouraging for the whole Alzheimer’s industry,” says professor Norbert Zilka, chief science officer at Axon. “Unlike amyloid, which influences speed of Alzheimer’s progression, there is strong evidence tau pathology relates to the underlying cause of the disease. Our vaccine aims to halt the formation and spread of tau pathology, which has ultimately the potential to show a higher benefit for Alzheimer’s patients.”
The study in prestigious British journal Nature Aging also shows tthat AADvac1 is “safe and well-tolerated.”
‘Pivotal stage of clinical development’
In the phase 2 trial of the AADvac1, 196 volunteers in their over 60 were recruited from eight countries across Europe. They were selected at random to receive several doses of the Alzheimer’s vaccine or a placebo over the course of two years.
“It led to high levels of antibodies against tau in the treated group,” says Novak. “AADvac1 shows robust antibody response, excellent safety profile and highly significant impact on neuro-degeneration.”
Larger trials are now being planned to replicate the results and further test the clinical efficacy. Benefits are expected include symptomatic relief and even the prevention of Alzheimer’s. “Our trial successfully demonstrated the strengths of AADvac1, a tau vaccine on track to prevent and treat Alzheimer’s disease,” says Michal Fresser, CEO of Axon Neuroscience. “The results confirm the disease-modifying effect and support Axon’s progress toward a pivotal stage of clinical development. In view of the recent approval of amyloid-based therapy, our strong NfL end point results could serve as a surrogate in our forthcoming clinical development to achieve accelerated approval.”
Axon currently boasts the single biggest team in the world dedicated exclusively to tau research, with more than 60 scientists and 15 senior scientists. Over the last two decades, it has published a large body of evidence demonstrating pathological tau is the main driver of Alzheimer’s disease.
SWNS writer Mark Waghorn contributed to this report.