Updated: Cortexyme's unorthodox Alzheimer's approach tripped up by FDA hold
The FDA has thrown a minor wrench in Cortexyme’s unorthodox plan to treat Alzheimer’s.
On Monday, the Bay Area biotech announced that the agency had put one of the studies in their pivotal program on hold after the company reported that patients experienced liver problems while taking their lead drug. The issues were reversible and had no known long-term effects, the company said.
The hold will not affect the Phase II/III, blinded, randomized controlled study they hope to read out towards the end of this year. Instead, the agency has decided to end, for the time being, an open-label extension study that had been measuring their molecule’s long-term effects on patients who already completed the initial 48-week study. No new patients will be enrolled and patients currently in the trial will be discontinued.
“Cortexyme’s highest priority is the safety of study participants,” Casey Lynch, Cortexyme’s CEO, co-founder, and chair said in a statement.
The hold took out of a quarter of Cortexyme’s $CRTX market cap, dropping shares from $47.47 to $36.
Cortexyme, which has been backed by Pfizer and Takeda Ventures, emerged from stealth mode in 2018 to pursue an alternative approach to Alzheimer’s. While most companies tried to directly cleave the amyloid plaques that build up in patients’ brains, generally floundering in the process, Lynch pursued an idea touted by a handful of renegade neuroscientists: that Alzheimer’s was caused by an infectious agent and the body’s inflammatory response to that agent.
Specifically, Cortexyme has gone after P. gingivalis, one of the bacteria that causes gum diseases. The bacteria has been found in the brain of Alzheimer’s patients and shown to lead to Alzheimer’s in mice models. Their drug, COR388, blocks a protease secreted P. gingivalis, inhibiting their ability to damage cells and slowly starving them by preventing them from getting food from those cells.
Although the hold marks a significant setback, the bigger test will come at the end of the year, when Cortexyme plans to announce whether COR388 slowed cognitive decline in a Phase II/III trial. The study, which the company believes will be pivotal, is already fully enrolled with 643 patients.