How Exelon works
Alzheimer’s disease is a progressive neurodegenerative disorder characterized by a slow worsening of memory and cognitive functions. The symptoms are caused by the death of nerve cells in the brain. Some of these nerve cells are involved in the production of a chemical messenger (a neurotransmitter), called acetylcholine. When acetylcholine is released, it passes on a message to particular nerve cells that can pick it up, It is then broken down by an enzyme (a biological catalyst) called acetylcholinesterase. Acetylcholine is involved in processes such as memory, thinking, and reasoning. It is thought that some of the symptoms of AD are caused by a reduction in acetylcholine and the loss of the cells that can receive the messenger.
Exelon is part of a class of drugs called cholinesterase inhibitors. It acts to reversibly block the function of acetylcholinesterase. By inhibiting this enzyme, it prevents the breakdown of the neurotransmitter acetylcholine and increases its levels in the brain. This can provide a temporary relief for some of the symptoms of AD, by improving the communication between nerve cells in the brain. However, Exelon cannot stop the progression of AD, as it does not address the underlying cause of the disease.
Exelon in clinical trials
Exelon has been extensively tested in clinical trials. The drug is available in two forms: as an orally-taken capsule or as a patch to provide slow release of drug over a 24-hour period.
Exelon was approved by the U.S. Food and Drug Administration (FDA) in 2000, in capsule form to treat mild to moderate AD based on three main clinical studies. For these three randomized, double-blind studies, a total of 2126 patients were prescribed either Exelon or a placebo for a period of 26 weeks.
The clinical trials assessed the effectiveness of Exelon by measuring the change in cognition and the ability to carry out daily tasks compared to the placebo using the Alzheimer’s Disease Assessment Scale-Cognition (ADAS-cog) test, which scores the patient based on a series of questions to measure memory, language skills, and reasoning. A higher score implies the patient is experiencing more severe AD symptoms, and the score usually increases each year as the disease progresses. Another test called the Clinician’s Interview-Based Impression of Change (CIBIC) assesses the patients’ ability to perform general daily tasks such as eating, dressing, shopping, and household chores as well as their cognition and behavior. The results of the trials showed that patients treated with Exelon experienced a significantly smaller increase in their test score compared to those treated with placebo, suggesting that Exelon successfully reduced the symptoms of AD.
Exelon was approved for marketing as a patch based on a Phase 3 clinical trial called IDEAL, which demonstrated an increase in efficiency of the patch compared to the capsule form of the drug. The results of the study were published in the scientific journal Neurology. Since June 2013, the Exelon patch is approved to treat all stages of AD, based on the results of another clinical trial called ACTION (NCT00948766), which showed a significant improvement in cognition and daily function of Exelon-treated patients compared to those treated with placebo. The results of this study were published in the journal CNS Neuroscience and Therapeutics.
The most common side effects associated with taking Exelon are nausea (sickness), vomiting, anorexia (lack of appetite), dyspepsia (indigestion), dizziness, and asthenia (weakness). Some patients also report that the Exelon patch causes a skin reaction at the site of application (such as redness or itching).
Note: Alzheimer’s News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.