A record-setting number of drugs for Alzheimer’s Disease are in the development pipeline this year—a clear sign that pharmaceutical companies are trying now more than ever to devise potentially viable strategies to treat the condition.
As of January 1, 2023, there were 187 trials assessing 141 unique treatments for AD. Disease-modifying therapies were the most common drugs, comprising 79 percent of drugs in trials.
Populating all current trials will require more than 57,000 participants.
This data was published earlier this year in Alzheimer’s & Dementia Translational Research & Clinical Interventions, which publishes an annual article about current Alzheimer’s Disease drugs in trial. The piece was authored by several researchers led by Dr. Jeffrey Cummings, director of the Chambers-Grundy Center for Transformative Neuroscience at the University of Nevada, Las Vegas.
Data from 2023 represents a significant uptick from data the same publication reported in 2022. Last year, as of January 25, 2022, there were 143 agents in 172 clinical trials for Alzheimer’s Disease.
Methodology for these studies was varied.
Study authors searched the governmental website clinicaltrials.gov, where are all clinical trials conducted in the United States must be registered. Authors used artificial intelligence and machine learning to ensure comprehensive detection and characterization of trials and drugs in development.
Study authors also used the Common Alzheimer’s Disease Research Ontology (CADRO) to classify drug targets and mechanisms of action of drugs in the pipeline.
New drugs must successfully complete a three-phase clinical trial process before being approved for use by the Food and Drug Administration (FDA); they must perform well enough in each phase to progress to the next one. Preclinical studies in laboratories establish a scientific basis for believing a drug is reasonably safe and may be effective.
Phase I trials, the first stage of human testing, typically involve fewer than 100 volunteers and look at the risks and side effects of a drug. Participants at this phase are often healthy volunteers.
Phase II trials enroll up to a few hundred volunteers. These studies provide further information about safety and help to determine the best dosage of a drug, and are generally too small to provide clear evidence about a treatment’s benefit.
Phase III trials enroll several hundred to thousands of volunteers, often at multiple study sites worldwide. They provide the chief evidence for safety and effectiveness that the FDA will consider in deciding whether to approve a drug. No Alzheimer’s Disease drugs can be approved unless they pass all three phases.
Typically, as Dr. Cummings told BrainWise in a Q&A earlier this summer, there is a high rate of failure in Alzheimer’s Disease drug development with 99% of trials showing no drug-placebo difference.
Still the Alzheimer’s Disease drug development pipeline is leading to new therapies.
After a 17-year hiatus in drug approvals, two agents—aducanumab and lecanemab—have entered the market since 2021. Other drugs have shown promise in Phase III testing. Dr. Cummings said this data indicates there is hope for Alzheimer’s Disease patients.
Alzheimer’s Disease is increasing at an alarming pace as populations age. According to the Alzheimer’s Association, there are an estimated 6.2 million individuals with Alzheimer’s Disease in the United States and an estimated 50 million individuals with Alzheimer’s Disease globally. These populations will grow to 12.7 million and 150 million in the United States and globally, respectively, by 2050.