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Nov. 5, 2019 -- A Chinese drugmaker has stunned the world with news that it has won conditional approval from the Chinese equivalent of the FDA to sell a new drug for Alzheimer’s disease.

In a news release, Green Valley Pharmaceuticals says it will sell the drug -- GV-971, or Oligomannate -- in China by the end of the year.

In a field littered with drug disappointments, it is the first approval of any new agent to treat Alzheimer’s since 2003.

Oligomannate is a sugar derived from seaweed. The company says it works by modifying gut bacteria to ultimately turn down inflammation in the brain.

But there is scant proof to back up those claims.

Last year, the scientists developing the drug published an article in the journal Cell Research showing that the compound appears to change gut bacteria and brain inflammation in mice that were genetically engineered to have the disease.

But mice are not people, especially when it comes to the brain. For every 100 drugs for brain diseases entering clinical trials -- typically because they worked in mice -- only nine go on to be approved for people. That’s one of the lowest success rates for any therapeutic area.

There is data on the medication in people, but it hasn’t been published in a peer-reviewed medical journal, where outside experts scrutinize and critique a paper before it’s presented to the public.

A news release published by the company Monday gave details of a phase 3 study, done in 34 hospitals in China, in 818 people with mild to moderate Alzheimer’s disease. Study participants were randomly assigned to receive Oligomannate pills twice a day or a placebo. Doctors gave them tests to measure changes in their thinking and memory over time.

Both groups showed improvements in their test scores, but the group taking Oligomannate had better improvement on one test, called the ADAS-Cog12, compared to those who were taking the placebo. There were no differences between the two groups on other kinds of tests given to patients.

Aaron Ritter, MD, director of clinical trials at the Cleveland Clinic’s Lou Ruvo Center for Brain Health in Las Vegas, urged caution over the announcement.

“The findings need to be replicated in order for this to be safely prescribed,” he says. What’s more, the benefits seen with the drug “were not that much different than what we’re seeing in drugs that are currently available in the marketplace,” including drugs like Aricept.

So while it is an interesting idea that you could turn down disease in the brain by changing bacteria in the gut, Ritter says far more study is needed to show that this medication works.

“This is certainly not the panacea for Alzheimer’s disease that people are reaching for,” he says.

Maria Carrillo, PhD, chief science officer of the Alzheimer’s Association, says in a statement that she is intrigued by the chance that this drug may work through communication between the stomach and brain and immune system to benefit memory and thinking skills.

“That said, little is known at this point about exactly how the drug works,” she says. “At this time, the Alzheimer’s Association cannot recommend that anyone in the U.S. take this drug until it has met the safety and efficacy standards of the U.S. FDA.”

Derek Lowe, whose blog about drug discovery appears on Science Translational Medicine, wrote about an earlier study of Oligomannate that found the compound did not appear to perform better than a placebo. He also found a slide from the study, presented at a recent Chinese biomedical conference. The slide shows the group of patients taking the placebo saw a rapid and unexplained decline in how well their brains worked 6 months into the study. This sharp drop appears to drive most of the 2.54-point difference between the placebo and drug groups.

There were also questions about the company’s history. As noted in Lowe’s blog, Chinese journalists posted stories about another drug sold by the company, derived from a fungus, that had been marketed as a cancer cure. Lowe writes that the aggressive claims drew the attention of law enforcement and led to lawsuits from customers.

Chinese regulators will require the company to do more studies of the compound for safety. And Green Valley has promised to seek approval for its medicine in other countries. It pledged to do global clinical trials “in the near future.”

WebMD Health News


Aaron Ritter, MD, director of clinical trials, Lou Ruvo Center for Brain Health, Cleveland Clinic, Las Vegas.

Maria Carrillo, PhD, chief science officer, Alzheimer’s Association.

In the Pipeline blog, Nov. 5, 2019.

News Release, Green Valley Pharmaceuticals, Nov. 2, 2019.

PubPeer, accessed Nov. 5, 2019.

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