Imagine if you could help treat someone with Alzheimer’s disease just by donating blood.
Eventually, that might be a possibility.
New research found that blood plasma infusions from young donors resulted in some signs of improvement in people with mild to moderate Alzheimer’s disease.
The goal of the study, presented at a conference earlier this month, was to establish the safety of administering the infusions.
Seeing improvements in people from four weekly infusions was surprising.
The improvements were seen in functional abilities, such as remembering to take medications, paying bills, or cooking for oneself.
“I thought that the study would prove that the young plasma was safe and hoped we would find trends for improvement,” Dr. Sharon Sha, a neurology professor at Stanford University in California who led the study, told Healthline, “but we were happily surprised that we found improvements on some measures of functional ability.”
Building on research
The Stanford study included just 18 participants.
Most of the hope for an eventual plasma-based treatment comes from a previous study, on which the new research builds upon.
That study had found that blood from younger mice improved older mice’s cognitive abilities.
“We don’t know yet if this will work in humans,” the study’s senior author, Tony Wyss-Coray, PhD, a Stanford neurology professor, said when his research was published in 2014.
Wyss-Coray has since co-founded a biotech company, Alkahest, that holds some intellectual property related to the plasma infusions.
Alkahest sponsored the new study, but Wyss-Coray wasn’t involved in the research, according to Stanford.
The efficacy of the blood transfusion treatment is still really based on the animal studies, and the small study size is problematic “because we know people sometimes react really well just to being in a trial, because of all the monitoring and all that,” James Hendrix, PhD, director of global science initiatives at the Alzheimer’s Association, told Healthline.
But, he said, “it’s exciting to see it move forward in human trials.”
“I do see a path forward for it,” Hendrix said. “It is something that you could envision the possibility of — to ask young people to donate to help those with Alzheimer’s.”
Supply could be a problem
There are about 5.5 million Americans with Alzheimer’s and nearly 50 million worldwide, a figure that’s expected to increase as the growing population ages and lives longer, according to the Alzheimer’s Association.
Donating plasma takes more than an hour and should be done no more than about once a month, according to the American Red Cross.
So, even if a plasma-based treatment were eventually shown to be effective, obtaining enough to make a difference on a large scale may be tricky.
But if it turns out to be an effective treatment, we’ll find a way, Hendrix said.
“Scale could be a challenge, but given the huge medical need, it’s something that could be possible,” he said. “If it’s really shown to be effective, it would be a lot cheaper and a lot more humane” than not attempting to treat people with Alzheimer’s.
What’s in blood?
If the treatment is proven effective, researchers could then eventually find out what exactly it is in plasma that’s reversing the cognitive decline.
Those substances could be isolated and replicated, decreasing overall plasma needs.
Hendrix noted other research efforts are working to find out if specific proteins in plasma could be key to a treatment.
The pharmaceutical company Grifols, for instance, is looking into swapping patients’ plasma out, based on the idea that this might flush amyloid-beta from the brain.
Amyloid-beta is a protein that’s known to accumulate in the brains of people with Alzheimer’s. It’s thought to bind to albumin, one of the proteins in plasma.
Grifols also owns a stake in Alkahest.
A 500-person study testing the blood transfusion hypothesis is due to wrap up next year.
In the Stanford study, nine participants were given four weekly infusions of either plasma from 18- to 30-year-old donors or a placebo saline solution.
Then, after a six-week “wash-out” period, those who had received the plasma received the placebo, and vice versa.
Later, to reduce the number of trips participants needed to make to the hospital, another nine participants all knowingly received the plasma infusions, with no control or placebo.
No significant change was found in the participants’ moods or cognitive abilities, like memorization or recalling events. But functional abilities did improve.
The biggest changes from the plasma infusions were seen in the first group, which didn’t know whether they were getting plasma or placebo.
The next step, Sha said, is “to determine whether this could be replicated in a larger sample of patients.”
If so, they’d then, as Hendrix imagined, move on to determining which components of plasma are making a difference in patient outcomes “and possibly replicate or isolate those components.”