New Alzheimer’s drug trial gives researchers optimism
Better diagnostics allow more targeted testing
No effective treatment for Alzheimer’s is yet in sight, but better diagnostics, deeper scientific understanding and an encouraging drug trial are leading to a positive mood as the largest Alzheimer’s research conference of the year began Sunday in Chicago.
“There have been plenty of disappointments, and sadly, I’m an expert in those disappointments,” said Stephen Salloway, director of the Memory and Aging Program at Butler Hospital in Rhode Island and a professor of neurology at the Alpert Medical School of Brown University. But “I’m quite bullish and think we’re making significant progress.”
Much of the optimism surrounds a drug trial that will report more details at the Alzheimer’s Association International Conference. In that small trial, a drug seems to have removed a protein called amyloid, the hallmark of Alzheimer’s. All previous trials attacking amyloid, including some costing hundreds of millions of dollars, have failed. The new study suggests that’s because patients were given too little, too late.
“You’re going to have to move early and be very aggressive,” said Reisa Sperling, who directs the Center for Alzheimer Research and Treatment at Brigham and Women’s Hospital in Boston.
Eighteen months after they began taking the experimental drug – called BAN2401 – patients who received the highest dose saw a dramatic drop in the amyloid in their brains as well as signs that disease progression had slowed, according to Biogen, which is developing the drug along with Japanese company Essai.
“I’ve seen the data and I find them very encouraging for a change,” said Sperling, a professor of neurology at Harvard Medical School.
Exactly how early the treatments should be started remains unclear.
Other trials, including the recently announced Alzheimer’s Prevention Initiative Generation Program, a collaboration between drug companies Novartis and Amgen and the nonprofit Banner Alzheimer’s Institute, are trying similar drugs earlier in the disease, before people have noticeable symptoms.
Such early approaches are largely possible because of a diagnostic test approved in 2012 that can confirm amyloid in the brain before the person suffers obvious memory loss. The PET scan diagnostic is not available to most patients, because it’s not routinely covered by Medicare, but it has been used in clinical trials to make sure that only people who have amyloid in their brains are given the anti-amyloid drugs. Many earlier anti-amyloid drug trials turned out to have included people who had dementia but not Alzheimer’s, so the drug would never have worked on them.
About 5.7 million Americans have Alzheimer’s disease, the most common form of dementia. That number is ex- pected to climb to nearly 14 million by 2050, as the population ages.
Although anti-amyloid drugs are still considered the most promising to treat early forms of Alzheimer’s, researchers are also developing candidate drugs that act on other aspects of the disease. An experimental diagnostic PET scan can visualize the buildup of another protein characteristic of Alzheimer’s, called tau.
Trials are underway to see if drugs that remove tau will benefit people with Alzheimer’s. Sperling said she’s excited about the potential of the work but notes that researchers must still figure out how much of the drugs to give, which form of tau to go after and what stage of the disease to treat. “We have years of work ahead,” she said.
A combination of treatments – maybe an anti-amyloid and an antitau drug – might prove to be the best approach, particularly as the disease advances, Sperling said.
People at later stages of the disease have very little to help them right now, and not much on the near-term horizon, Salloway conceded.
“We haven’t had a new treatment for symptomatic Alzheimer’s for more than 13 years,” he said. “I’m not seeing anything at the moment.” He and other researchers pointed to a drug recently approved for psychosis among Parkinson’s disease patients that might also prove useful in Alzheimer’s.
Pierre Tariot, a geriatric psychiatrist and director of Banner Alzheimer’s Institute, said he’s hopeful some new therapies will come along in the next three to five years that will address the emotional and psychological aspects of the disease and others that will allow people to hold on to their intellectual function longer.
Patients and their loved ones would be grateful for any improvements that allow them to participate in family events or even something as simple as making their own breakfast. “They’re not looking for miracles,” he said.
The target of the research is a new attack on a protein called amyloid, the hallmark of Alzheimer’s. All previous trials attacking amyloid have failed.