There was disappointing news recently on a drug many had hoped would provide some relief for patients suffering with Alzheimer’s Disease (AD). Eli Lilly, the pharmaceutical company developing the drug Solanezumab announced that a round of clinical trials for the drug did not show a slowing of cognitive decline in test subjects that were given the drug. The clinical trials included 2,100 patients, half of whom were given the drug, and half of whom were given a placebo. When testing the patients for memory, cognition and mental decline, those who received the drug were not better off, at least not to a statistical significance.
The drug was designed to absorb amyloid plaques in the brain, which are indicated as a cause of AD. Amyloids are proteins that collect in deposits on the brain, but they are abnormal and can result in cell death and memory loss. Research into AD has shown time and again that patients who develop these plaques usually have some form of dementia, most often AD. Nerve cells in the brain seem to attract clumps of the protein and when that happens, communication between cells is diminished, resulting in the cognitive decline that is the hallmark of AD. When enough of the proteins accumulate, cells can die. No treatment exists to reduce or remove them and many in the neuroscience community, both patients and health care providers, were hopeful that Solanezumab would be a first. The drug, which contains an antibody to the amyloid proteins, showed some promise in earlier trials, however the most recent research suggests that it will not be the game changer hoped for.
John C. Lechleiter, Ph.D., chairman, president and chief executive officer, Lilly said in a statement, “The results of the solanezumab EXPEDITION3 trial were not what we had hoped for and we are disappointed for the millions of people waiting for a potential disease-modifying treatment for Alzheimer's disease. We will evaluate the impact of these results on the development plans for solanezumab and our other Alzheimer's pipeline assets. While the study results, including many secondary clinical endpoints, directionally favored solanezumab, the magnitudes of treatment differences were small. There were no new safety signals identified in the study. Lilly will not pursue regulatory submissions for solanezumab for the treatment of mild dementia due to Alzheimer's disease.”
Patients in the study were evaluated for cognitive abilities using the Alzheimer’s Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) which measures cognitive ability through word recall testing, remembering task directions, completing simple tasks and comprehending and using spoken language. It’s the most commonly used assessment tool to measure cognitive decline as well as how this decline affects mood and behavior.
Dr. David Reynolds, chief scientific officer at Alzheimer's Research UK, in an interview with FierceBiotech said, “While today’s results are a setback for the amyloid hypothesis, there are several other anti-amyloid drugs still in clinical trials that work in different ways, some of which are being tested even earlier in the disease process than solanezumab. We can't disregard these ongoing trials and their findings will now be more important than ever in shaping the search for disease-modifying treatments for Alzheimer's.” Reynolds pointed out that the pharmaceutical company Biogen is testing a slightly different protein antibody, aducanumab, that is also designed to act on the formation of amyloid plaques so researchers will be watching those trials carefully, hoping for better results. The video below explains more about this devastating news.
Sources: Eli Lilly NBC News FierceBiotech VeryWell.com