Green Valley to start US trials of algae-based Alzheimer’s drug

Shanghai Green Valley Pharma’s controversial Alzheimer’s disease therapy GV-971 has been cleared to start clinical testing in the US by the FDA.

The algae-based drug – also known as oligomannate – was granted approval for the treatment of mild-to-moderate Alzheimer’s last year by China’s National Medical Products Administration (NMPA), becoming the first new drug to be approved for the disease since memantine in 2003.

The drug is a low molecular acid oligosaccharide compound extracted from marine brown algae and was approved in China on the condition that it show efficacy in larger-scale trials – and there is a fair degree of scepticism that it will meet that objective.

Green Valley says it now has FDA approval for the Investigational New Drug (IND) application covering the US arm of its planned global trial of GV-971, which aims to enrol 2,000 patients in the US, Europe and Asia.

Last year, Green Valley said that patients with mild-to-moderate Alzheimer’s who received a twice-daily oral dose of oligomannate over 36 weeks showed a statistically-significant improvement over placebo on the ADAS-Cog 12 scale of cognitive function.

The average difference between GV-971 and placebo on that score by the end of the study was 2.54, said the drugmaker. A three-point decline on the scale is viewed as a clinically significant worsening of Alzheimer’s symptoms.

The drug failed to improve scores on the CIBIC-Plus scale of dementia symptoms compared to placebo, however, and the study didn’t look at other endpoints like levels of amyloid beta or tau proteins – two Alzheimer’s biomarkers that aggregate in the brain to cause characteristic plaques and tangles.

The Chinese drugmaker’s scientists have suggested that GV-971 may work by altering the balance of microorganisms in the gastrointestinal tract that contribute to inflammation in the central nervous system.

That is a very different mechanism of action to the legion of amyloid and tau targeting drugs that have been tested and almost without exception failed in Alzheimer’s trials.

Biogen is hoping to buck that trend with its amyloid-targeting aducanumab, due to be filed later this year after a delay caused by the coronavirus pandemic, although that is also viewed as a high-risk project.

Green Valley has said it intends to have the global trial underway this year – pending other regulatory approvals – and hopes to have data from the trial in time to file for marketing approvals in 2025 if all goes well with the study.

The trial will include a placebo controlled phase lasting for one year, with all subjects then switched to an open-label extension for six months, according to a Bloomberg report.