Oligomannate: Seaweed / Brown Algae Extract to Treat the Symptoms of Alzheimer’s & Other Dementias

Last Updated: February 14, 2020


In late 2019 Chinese regulators approved the sale of the first new drug for dementia symptoms in almost 20 years. It’s called Oligomannate, and clinical trials have given researchers hope that it may relieve the thinking and memory problems that are so prevalent for our loved ones suffering with Alzheimer’s.

This is a big deal! In almost 20 years, pharmaceutical companies have started hundreds of clinical trials looking for a compound that could alleviate, or even cure, dementia. None have gotten regulatory approval into Phase II since Namenda in 2003. The Chinese pharmaceutical company Shanghai Green released Oligomannate to Chinese residents late last year, and global tests are expected in 2020, which could lead to availability in the United States.

So, what is Oligomannate?

What is Oligomannate?

Oligomannate is made of extracts from brown algae. Put another way, it’s sugar derived from seaweed or kelp. (Seaweed looks like a plant, but is actually algae.) Researchers tested Oligomannate in pill form in double-blind, placebo-controlled trials. That means groups with dementia were given either the Oligomannate drug or a placebo (which is like a sugar pill, something with no actual benefit). What they found is that the group that took the algae extract showed a statistical improvement in cognitive function, or thinking ability. This improvement was shown after only four weeks in some subjects, and continued over follow-up assessments.


How Does Oligomannate Work?

Scientists have long believed there is a link between gut bacteria and the brain. Within our intestines are germs (metabolites) which serve purposes including keeping our immune systems strong. In people with Alzheimer’s disease, the gut bacteria changes to produce harmful cells that affect swelling in the brain. The dementia-causing proteins called amyloid-beta and tau increase in the brains of people with this gut-bacteria issue.

Oligomannate was shown, first in laboratory mice, to block the rise in harmful intestinal bacteria, reducing the buildup of proteins that cause swelling in the brain and bring symptoms like memory loss. The complete results of clinical trials by Shanghai Green Valley Pharmaceuticals were not announced, but the company did confirm that there was significant improvement in thinking and memory for people with Alzheimer’s disease who took Oligomannate twice a day for 36 weeks.


For Which of Stages of Dementia is Oligomannate Effective?

The drug showed benefits for people with mild-to-moderate Alzheimer’s. This means someone in the later stages of dementia probably won’t see a benefit to taking Oligomannate, but people in the earlier and middle stages could see their symptoms improve.


How Much Will Oligomannate Cost?

The pill available in China is 150 milligrams and costs the equivalent of about $500 for one month’s supply. Because the drug is not yet available outside China, an issue like insurance coverage can’t be addressed yet. Medicare Part D, which covers prescriptions, and Medicare Advantage, which is tailored to specific individuals, can cover the cost of other Alzheimer’s drugs like memantine and cholinesterase inhibitors, so it is possible that if/when Oligomannate becomes available globally, these Medicare programs will cover costs for your loved one to try the new medicine.


Side Effects of Oligomannate

There have not been reported side effects. This doesn’t mean the drug is completely safe, but reporting on Oligomannate says side effects were similar to a placebo. One of the reasons more trials are required before the drug becomes widely available is that researchers must determine exactly which side effects people will experience if they start taking the drug. It’s possible longer-term issues simply haven’t surfaced yet. In fact, some skeptics have argued that the clinical trials so far have been too short to evaluate the medium- to long-term effects, including side effects.


How To Get Oligomannate

Shanghai Green, the drug’s manufacturer, has said it will roll out global trials in 2020, including at sites in the U.S. The company has not, however, been more specific about where and when these trials will be held. A good place to check is the National Institute on Aging’s engine for finding Alzheimer’s disease trials, available here. If an opportunity to be part of the Oligomannate trials comes up, it’s likely to appear on that page. Read more about clinical trials for dementia.


Is There A Supplement Alternative to Oligomannate?

Maybe. Brown algae, brown seaweed, and kelp supplements are available to take as pills, drops, or powder to add to food or beverages. These are marketed as nutritious and useful in digestion, but the supplement market is notorious for loose regulations. Try to purchase supplements from a source you can trust, and have realistic expectations. Supplements are not pharmaceuticals, so the benefits of taking straight brown seaweed in pill form may not match the drug Oligomannate, even if the drug is made from brown seaweed extract. More on dementia supplements.