Alzheimer’s disease patients, caregivers and researchers just got more bad news when another drug company halted its late-stage trial of a drug that had sent ripples of hope through the community.
Merck announced earlier this week that it was halting its work with verubecestat in the EPOCH clinical trial after an independent study found that it had “virtually no chance” of working. The company, however, will continue to research the potential of the drug in another trial, called the APECS.
That follows other similar announcements by other drug companies. Three months earlier, Eli Lilly ended the clinical trial of its Alzheimer’s drug solanezumab. It said patients had not shown any sign of improvement when compare to those taking a placebo.
These recent announcements have been especially disappointing because it’s been more than 10 years since a new drug has gone on the market to alleviate the symptoms of Alzheimer’s. What’s more, there has been no treatment to slow or prevent the disease either.
About 47 million people currently live with dementia, which is marked by a gradual decline in memory and leaves sufferers unable to care for themselves. Of those dementia cases, 60 to 80 percent suffer from Alzheimer’s. As the world’s population ages, that number is predicted to double every 20 years to reach 131 million people in 2050, according to Alzheimer’s Disease International. In the U.S. the Alzheimer’s Foundation estimates that as many as 5.1 million Americans may have the progressive disease.
“While we are disappointed that a benefit was not observed in this study, our work continues [to study the impact of] verubecestat in people with less advanced disease,” Dr. Roger Perlmutter, president of Merck Research Laboratories, told CNN.
Preventing and curing Alzheimer’s has been particularly challenging. Researchers still don’t know what exactly causes the loss of connection in the brain that ultimately leads to cognitive decline. Though there have been successful studies reducing memory loss in lab animals, this so far hasn’t been replicated in humans.
Researchers speculate that amyloid plaque build-up in the brain may be one of the main causes of the disease. Verubecestat works to control an enzyme involved in the formation of these abnormal protein plaques, so several pharmaceutical companies are investing big money to test drugs like verubecestat, which inhibit the plaque. These include AstraZeneca and its research partner Eli Lilly, Novartis in collaboration with Amgen, and Janssen and Biogen.
Some say verubecestat’s failure calls into question the underlying assumption that these amyloid plaques are the main cause of the disease. However, there are still promising trials testing that hypothesis, including ongoing trials with aducanumab, being run by Biogen, which has so far reported encouraging signs.