Dementia is a global epidemic, affecting nearly 50 million people worldwide. By 2050, it’s estimated that 115 million people will suffer from some form of dementia. Alzheimer’s disease (AD) is the most common type of dementia occurring late in life. AD is also the only condition among the leading causes of death that cannot currently be prevented, cured or even significantly slowed.
Despite intensive research, we have seen no new Alzheimer’s medications since 2003, when memantine (marketed as Namenda®) was approved by the FDA. For those living with Alzheimer’s disease and their loved ones, there is a significant unmet need for progress in understanding and treating this most prevalent form of dementia. In 2010, Congress passed the National Alzheimer’s Project Act to create a national plan to address AD, and in 2012, that plan articulated the goal of preventing and effectively treating AD by 2025.
For sponsors who are pursuing this ambitious goal, understanding the obstacles inherent in Alzheimer’s clinical trials can help in planning for, and overcoming, these challenges.
Treatment Landscape
Treatments for Alzheimer’s disease can be classified according to two broad categories:
1. Symptomatic Therapies
Approved symptomatic therapies include the cholinesterase inhibitors (donepezil, rivastigmine, and galantamine) and memantime, a glutamate-NMDA receptor modulator. Other cholinesterase inhibitors, nicotine receptor agonists, serotonin receptor modulators, h3 histamine receptor antagonists, and numerous other neurotransmitter system-targeting agents have been investigated without success. Currently, sigma1 and muscarinic receptor modulators, intranasal insulin, peroxisome proliferator-activated receptor gamma agonists, and glucagon-like peptide 1 agonists are under development and investigation.