Despite thousands of research studies and millions of dollars dedicated to clinical trials, a drug to treat Alzheimer's disease (AD) has yet to be found. Biogen, a pharmaceutical company, headquartered in Cambridge MA has a drug in clinical trials that is showing some early promise.
Aducanumab is an investigational compound being developed for the treatment of Alzheimer's disease. It's a human recombinant monoclonal antibody (mAb) derived from a de-identified library of B cells collected from healthy elderly subjects with no signs of cognitive impairment or cognitively impaired elderly subjects with unusually slow cognitive decline.
It targets the sticky beta-amyloid proteins that accumulate in the brains of patients with Alzheimer's. As the disease progresses, the plaques grow and tangle around brain tissue, interfering with memory and cognition. While the cause is still unknown, research has been focused on eliminating or slowing the progression of the proteins as a way to manage the disease. Recent trials at the University of Zurich showed that after a year of treatment with Aducanumab, cognitive decline in AD patients was slowed significantly, compared to the group who received a placebo.
Roger M. Nitsch, a professor at the Institute for Regenerative Medicine at UZH, led the research and explained, "The results of this clinical study make us optimistic that we can potentially make a great step forward in treating Alzheimer's disease. The effect of the antibody is very impressive. And the outcome is dependent on the dosage and length of treatment." After one year of treatment, practically no beta-amyloid plaques could be detected in the patients who received the highest dose of the antibody."
The antibody was developed by taking blood samples from healthy older adults with no cognitive decline. Since Aducanumab works by binding to beta-amyloid proteins so that microglial cells can destroy the plaques. It's important that the blood samples from healthy elderly patients are sorted out, and the immune cells that seek out the beta-amyloid are isolated. There's a protein that is quite similar to beta-amyloid. However, it's involved with the growth of nerve cells throughout the body. Aducanumab was designed to bind only to the toxic beta-amyloid, leaving the pre-cursor proteins to do their work.
There were 165 patients in the Zurich study. While the point of the research was to see if the drug could eliminate beta-amyloid plaques, the team also noticed that cognitive decline was also slowed. The researchers added questionnaires to the study so they could evaluate how the patients were doing cognitively. Nitsch stated, "Aducanumab also showed positive effects on clinical symptoms. While patients in the placebo group exhibited significant cognitive decline, cognitive ability remained distinctly more stable in patients receiving the antibody."
There were a small number of patients who experienced an adverse effect known as amyloid-related imaging abnormality (ARIA). The reported headaches that were mild to moderate, which is a result of swelling that can occur when amyloid plaques are being cleared from the brain. There are currently two Phase 3 clinical trials ongoing with Aducanumab, and those studies are happening in 300 centers in 20 countries, and include more than 2700 Alzheimer's patients. The video below details the experience of one woman who is participating in one of the studies, take a look.