There is lots of room for both success and failure in the Alzheimer's drug market.
While current Alzheimer’s disease (AD) treatments are limited at the moment, there are a number of promising drugs in the pipeline.
Globally, there are 646 treatments for AD in active development-albeit in the early stages-according to a recent GBI Research report, “Frontier Pharma: Alzheimer’s Disease and Associated Indications-Exceptional Level of First-in-Class Innovation within AD, and Diverse Range of Therapies in Development for Disorders Such as Anxiety and Depression.”
“The AD pipeline is large,” GBI Research Analyst Fiona Chisholm told Drug Topics.
Notably, among the treatments in the pipeline with a disclosed molecular target, 65.3% are the first in their class. “This represents a very high level of first-in-class innovation in comparison to pipeline products across the entire industry, where just over one third of products are first-in-class,” Chisholm said.
Although this degree of innovation is encouraging, it likely reflects the large number of difficulties and setbacks the AD field has experienced in terms of translating knowledge of pivotal targets into clinically beneficial therapeutics, Chisholm said.
For example, the pipeline contains several tau inhibitors and amyloid beta (Abeta) inhibitors. “These drug classes have been extensively investigated in AD but none of these drugs have achieved regulatory approval to date,” Chisholm said.
GBI Research’s data focuses on early-stage innovation (the developmental stages that occur prior to the product entering clinical development), which means they may not necessarily be products that will be developed into marketable drugs.
For example, one of the products in the pipeline, GM-6, is an inhibitor of apoptosis regulator BAX, a protein that mediates programmed cell death. Early research from cellular and animal studies suggests that inhibition of BAX can prevent nerve cell loss, according to Chisholm.
Other products in development include those targeting apolipoprotein E (APOE). “This is a multifunctional protein that is involved in the regulation of processes such as lipid transport, immunoregulation, and neuronal growth and repair,” Chisholm said.
Preclinical studies of drugs acting on BAX and APOE demonstrate potential disease-modifying effects that could delay the onset of symptomatic AD in high-risk patients or slow disease progression in the early stages of symptomatic AD.
“However, given the challenges associated with the development of disease-modifying drugs in AD, particularly in terms of translating findings from cellular and animal research into clinical benefits, this evidence should be interpreted cautiously,” Chisholm said. “As these drugs are in the early stages of development, it is likely to be at least five to ten years before they enter the market, if successful.”
There are currently limited treatment options for AD because many aspects of the disease’s pathophysiology remain incompletely understood, “which poses a major barrier to innovative drug development,” Chisholm said.
In addition, although investigational drugs targeting neuropathological hallmarks of AD, such as Abeta, have been researched extensively, they have largely proven to be unsuccessful in clinical trials.
“Consequently, the clinical trial failure rate is extremely high in AD. Drug development therefore remains very high-risk, which can further deter companies from investing in this area,” Chisholm said.