Cassava Sciences (SAVA) fell ~14% in the premarket on Friday after the company said it will be forced to delay a clinical trial for its lead candidate, simufilam, for a form of epilepsy, as it moves to address several concerns raised by the U.S. FDA.
The setback relates to a proof-of-concept clinical trial for simufilam in tuberous sclerosis complex (“TSC”)-related epilepsy, for which the company has submitted an investigational new drug application seeking regulatory clearance for its initiation.
In an SEC filing on Thursday, the Austin, Texas-based biopharma added that the FDA has sent it a formal letter regarding the IND, noting that the proposed study is on full clinical hold pending further information, such as additional preclinical data from the company.
Cassava (SAVA) said it “intends to work expeditiously to address” the FDA’s concerns, and as a result, it no longer expects to begin the trial in H1 2026 as previously disclosed.
The company has already phased out its Alzheimer’s disease development program for simufilam following a late-stage trial setback for the oral therapy.