Analysts and stockholders “love” aducanumab, a new drug from Cambridge-based Biogen. The biotech company in March published the findings of a study that showed promising results for Alzheimer’s patients who took the drug. However, patients and their families might not entirely love what Meg Boyce, vice president of programs and services at the Alzheimer’s Association of the Hudson Valley has to say about it. “It is very encouraging—however, a Phase 1D clinical trial really is for safety and tolerability rather than what the benefits are,” said Boyce. “It’s important that they’re putting funding towards taking that next step where they will have a larger group of individuals on the medication, along with a placebo, for a longer period of time.”
Though the drug has been deemed safe and tolerable for human consumption—the trials published in March were the first to be tested on human subjects—the efficacy of the drug cannot be determined until a test is done on a larger number of individuals (this test used 166 patients) over a longer period of time.
“There’s still a lot of skepticism because there are a lot of people out there who are kind of surprised this worked,” said Westchester Magazine Top Doc Stephen Marks, MD, professor of clinical neurology at New York Medical College, who is attending at Westchester Medical specializing in vascular neurology and dementia.
Marks explained that the medical community is split between believing that Alzheimer’s is caused primarily by a buildup of amyloid plaque in the brain, and believing that it’s caused by an accumulation of abnormal tau protein. “I think of the brain as an organ that has to recycle a lot of its metabolites, and we have to put out protein and recycle it. Alzheimer’s patients have misfolded protein which becomes amyloid plaques,” said Marks. Aducanumab works to target amyloid plaque, so much of the skepticism comes from those in the tau protein camp.
The drug is promising, though. Despite the relatively small 166-participant sample size (it’s estimated that around 5 million people have Alzheimer’s in the United States alone), those who were given a dosage responded well—their amyloid plaque buildup decreased—and subjects who were given larger doses responded better according to their PET scans. Marks speculated that aducanumab would likely be targeted at those with prodromal (mild or early-onset) Alzheimer’s. “Two percent of Alzheimer’s is early-onset and genetic; the other 98% is what we typically see in older people,” said Marks. “It’d be interesting to give to children of genetic Alzheimer’s [patients] to see if we could prevent them from getting it at all.” Treating Alzheimer’s in later stages is much more difficult, and drug studies that have targeted patients in that 98% category have not shown as much success as the the aducanumab results, according to Marks.
Not only did aducanumab show a decline in amyloid plaque, their clinical dementia ratings (CDR) improved, as did their results on mini mental status exams.
Boyce said, “Medications out there—none of them slow the progression of the disease, and family members have different experiences with efficacy of treatment for loved ones.” These other medications include Memantine, which works as a modulator of glutamate, and Aricept, which works to increase acetyl choline, a transmitter in the brain that deals with memory. Adumanucab is unique because, as is currently speculated, it could slow down the development of Alzheimer’s rather than only treat symptoms.
“We have to do a bigger study to validate this, but it worked out nicely,” Marks said. “I wouldn’t be surprised if it did meet the approval of the FDA, it seems to be a pretty safe medicine…What I’ve been telling my patients is to stay tuned.”
Boyce came to a similar conclusion: “Keep it on your radar, but we’re not there just yet.”
In the meantime, Marks urges his patients and the public at large to to keep on top of your blood pressure and and cholesterol levels, and that sedentary lifestyles are not conducive to Alzheimer’s prevention.
“The brain is a use it or lose it organ,” he said.
