A new plant-based compound for the treatment of Alzheimer's disease has been approved in China, drawing the approval of Alzheimer's researchers and neurodegenerative disease experts.
A Chinese biotech startup called Green Valley Pharmaceutical Co has developed a drug that it claims improves cognitive function in Alzheimer's patients by altering their gut microbiomes, ScienceInsider reports. In mouse studies, this approach reduced inflammation in the brains of rodents engineered to develop Alzheimer's-like pathology. The drug's makers are also claiming that a phase III clinical trial of 818 people demonstrated consistent improvements in cognition among patients treated with the drug compared to a control group. Though they haven't been published yet, the results convinced China’s drug regulator to approve the marketing of the drug, called GV-971, with the condition that the company gather additional safety and efficacy data, ScienceInsider says.
"This is very exciting and important; GV-971 is the first drug approved anywhere in the world for Alzheimer's disease since 2003," Jeffrey Cummings, an Alzheimer's researcher at the University of Nevada in Las Vegas, who is advising Green Valley, tells ScienceInsider.
"I think it's fascinating, and if it's true that [the effects are happening] through the microbiome, that's fantastic," Sangram Sisodia, a neurobiologist at University of Chicago in Illinois who has studied the impact of the microbiome on Alzheimer's disease in mice, tells ScienceInsider. But he also wants to see more evidence.
Some researchers also aren't completely convinced that the subtle improvement among Alzheimer's patients measured by a cognitive test is clinically meaningful, ScienceInsider adds.
"We're still cautiously optimistic," Rebecca Edelmayer, director of scientific engagement at the Chicago-based Alzheimer's Association, tells ScienceInsider. "I think we need to really understand for sure what kinds of changes are occurring through a medicine like this and how they actually relate to a disease process."
The active ingredient in GV-971 is a sodium oligo-mannurarate derived from brown algae. The company's original mouse study published in Cell Research in September suggested that an imbalance in the gut's microbiota produces immune cells that infiltrate the brain and exacerbate the neuroinflammation associated with Alzheimer's disease progression. Feeding the mice GV-971 remodeled their guts in a way that reduced the accumulation of neuroinflammatory cells, ScienceInsider says.
In a statement, Green Valley Pharmaceuticals described the phase III trial as a multicenter, randomized, double-blind, placebo-controlled, parallel-group, 36-week study. Although some researchers believe that the improvement the patients in the study exhibited weren't clinically significant, they also note that the study's 36-week time span is far too short to adequately assess the medium- to long-term effects of the medication.
Cummings tells ScienceInsider that GV-971 doesn't yet meet the criteria for approval in the US. But Green Valley says it plans to initiate a multicenter global phase III clinical trial with sites in the US, Europe, and Asia in early 2020 to gather data needed to support regulatory approval in other countries.