My Alzheimer's Journey
Part 75 -Alector Therapeutics AL137
I planned to write about Alector Therapeutics preclinical anti-amyloid beta antibody a few days ago. My own amyloid plaques were kicking my ass, though. When I don’t feel well, I joke that my amyloid plaques are causing problems. I have struggled with depression, anxiety, and extreme tiredness the past two days. I feel better today.
Alector’s new preclinical drug (AL137) is an anti-amyloid beta antibody. This class of monoclonal antibodies target and clear amyloid plaques in the brain. Lecanemab and Donanemab are in this class of antibodies. Monoclonal antibodies are treatments that target specific proteins and help your immune system fight disease. They can also reduce inflammation caused by your immune system.
Alector AL 137 is promising because it uses a delivery technology designed to cross the Blood Brain Barrier (BBB). Lecanemab and Donanemab are hindered by their difficulty penetrating the BBB. I understand that only a small fraction of Lecanemab and Donanemab effectively crosses into the brain and the central nervous system. Alector AL 137 is combined with Alector Brain Carrier (ABC) technology. This proprietary technology is designed to enhance the brain penetration of medications, enabling them to reach the brain in sufficient quantities and with the potency needed for efficacy.
BBB is a protective layer that lines the inner surfaces of the blood vessels inside your brain. I have read that the BBB is like a filter in that it keeps harmful things out of the brain, and it keeps helpful things in the brain. This is a very simple description of the BBB. In a later post, I will write about the BBB in greater detail.
Another benefit of Alector’s Brain Carrier technology is that it may help to reduce the risk of brain bleeding and brain swelling (amyloid-related imaging abnormalities, or ARIA). As someone who has had several MRI’s in the past few months checking for ARIA, reducing this risk is a huge benefit.
There is limited information available about AL 137 since it is an investigational drug. I did learn that Alector plans to submit an investigational drug application to the FDA for AL137 this year.
It is important to note that Alector is no stranger to the research and development of therapies for neurodegenerative diseases. In October, 2025, Alector pulled the plug on Lonlatozinemab during its Phase 3 trial. This drug was being developed in collaboration with GSK. A year earlier, Alector stopped the development of its investigational antibody AL002 when it failed Phase 2 trials. AL002 was being developed through a partnership with Abb-Vie.
Both of the failures resulted in significant employee layoffs. Nearly half of Alector’s staff was laid-off after the failure of the Lonlatozinemab trial. Shares of the company dropped 51% when the announcement was made. Today, Alector shares are trading at $1.91. The 52-week high is $3.40 and the 52-week low is $.87. As of September 30, 2025, Alector reported having $291.1 million on hand. At this third quarter reporting, Arnon Rosenthal, Ph.D., Chief Executive Officer of Alector, said “We are well-resourced to advance our portfolio of innovative drug candidates for the treatment of neurodegenerative diseases, with a sharpened focus on our differentiated Alector Brain Carrier (ABC) platform.”
I am telling you the financial situation of Alector because a lot of money will be required to take AL 137 through clinical trials. I hope they are able to successfully push AL 137 through the pipeline. A new Chief Financial Officer and Chief Business Officer was announced December 12, 2025. Let’s hope he can keep the Alector ship upright.
From my layperson’s perspective, AL 137 combined with Alector Brain Carrier technology seems very promising.
In addition to the links in the article, I also obtained research information from the following sources:
Alector ditches GSK-partnered dementia drug and cuts staff
Amyloid related imaging abnormalities (ARIA)
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