After decades of trying and dozens of failed trials, amyloid targeting has paid off with the first disease-modifying agents reaching the market. But success does not mean slam dunk. Aduhelm (aducanumab, Biogen Inc.) was dogged by controversy throughout its brief tenure, and Biogen pulled the plug on it in early 2024. Leqembi (lecanemab, Biogen Inc.) has received full approval. In this second installment of a three-part series on Alzheimer’s, BioWorld looks at the nuanced view of amyloid’s role in the disease.

After decades of trying and dozens of failed trials, amyloid targeting has paid off with the first disease-modifying agents reaching the market. But success does not mean slam dunk. Aduhelm (aducanumab, Biogen Inc.) was dogged by controversy throughout its brief tenure, and Biogen pulled the plug on it in early 2024. Leqembi (lecanemab, Biogen Inc.) has received full approval. In this second installment of a three-part series on Alzheimer’s, BioWorld looks at the nuanced view of amyloid’s role in the disease.

Alzheimer’s disease (AD) is recognized worldwide for its debilitating symptoms of declining cognitive function and gradual memory loss. What remains less clear is exactly what causes the neurodegenerative disease, and how to treat it. “Alzheimer’s disease is characterized by two key pathologies – beta-amyloid plaques and tau neurofibrillary tangles.” Seung-Yong Yoon, CEO of Adel Inc., told BioWorld. “Adel is looking to develop a tau-targeting drug, considering tau has been more correlated with AD symptom progression, and the industry’s need for tau pipelines.”

It is well known that protein tau forms aggregates in the brain in neurodegenerative diseases such as Alzheimer’s disease (AD) that are also known as tauopathies. Accumulation of protein tau in the brain leads to the cell toxicity and promotes the loss of synaptic plasticity, which in turn causes memory loss. As reported on Feb. 1, 2024, in The Journal of Clinical Investigation, assistant professor Tara Tracy and her research team from the Buck Institute for Research on Aging have discovered a protein in the brain that could restore this damage induced by protein tau.

Aquinnah Pharmaceuticals Inc. has announced preclinical research findings for a novel small-molecule therapeutic designed to slow or stop the progression of Alzheimer's disease and related disorders.

Protein quality control research is “almost exclusively focused on heat shock proteins, which are ubiquitously present” up and down the evolutionary chain, Xiaolu Yang told BioWorld. But “for more sophisticated organisms, which we humans like to think we are, it’s a little odd that we still use the system that bacteria started with…. It seems like we should have something more. The TRIM system,” he added, “fills that gap.”

Protein quality control research is “almost exclusively focused on heat shock proteins, which are ubiquitously present” up and down the evolutionary chain, Xiaolu Yang told BioWorld. But “for more sophisticated organisms, which we humans like to think we are, it’s a little odd that we still use the system that bacteria started with…. It seems like we should have something more. The TRIM system,” he added, “fills that gap.”

TRIMs or tripartite motif proteins are a group of quality control proteins that are found only in animals. One of their functions is to add ubiquitin tags to proteins, marking them for transport to the proteasome system. TRIMs are part of the innate antiviral defense system. But in the July 27, 2023, issue of Science, Yang, who is a professor of cancer biology in the Perelman School of Medicine at the University of Pennsylvania, and his colleagues reported that TRIM11 interacts with tau protein in multiple ways that were beneficial in preventing tauopathies.

Researchers from Washington University in St. Louis reported data validating microtubule-binding region (MTBR) of tau containing the residue 243 (MTBR-tau243) as a new cerebrospinal fluid (CSF) biomarker specific for insoluble tau aggregates in Alzheimer’s disease (AD).