Cassava Sciences halts Alzheimer's drug trial after limited progress

Cassava Sciences have drawn a close to their investigations and development of the drug simufilam, which they intended to be used for the treatment of Alzheimer’s disease. 

In a second Phase III trial, – REFOCUS-ALZ – simufilam failed to show any significant benefits in mild to moderate Alzheimer’s disease. Topline data released at the end of March shows that REFOCUS-ALZ did not meet all of the specified co-primary, secondary and exploratory biomarker endpoints. These endpoints namely included a change in cognition and function from baseline measurements to the end of treatment (at week 76). Simufilam was compared to a placebo and measurements were taken using ADAS-COG12 and ADCS-ADL scales. 

The REFOCUS-ALZ trial enrolled 1125 patients across more than 75 trial sites, and following a report from a previously undertaken 52-week Phase III study (called RETHINK-ALZ) where the co-primary endpoints were not met, was discontinued on 25 November 2024. 

A high number of the patients enrolled in REFOCUS-ALZ had completed their full study appointments by the time the trial was completed. The drug always demonstrated an overall positive safety profile. 

“We are disappointed that the results of REFOCUS-ALZ and RETHINK-ALZ showed no treatment benefit for patients with mild-to-moderate Alzheimer’s disease. These results were unambiguous. Working with patients, their families and their caregivers has brought a special dignity to our Phase III Alzheimer’s disease clinical trial programme and to each of us at Cassava. We are deeply grateful for the dedication and committed efforts of study investigators and site teams, who enabled us to conduct these trials with integrity and scientific rigor and whose efforts provided a clear data read out,” stated Rick Barry, President and Chief Executive Officer of Cassava.

“Cassava will discontinue all efforts to develop simufilam for Alzheimer’s disease and we expect to phase out the programme by the end of Q2 2025,” continued Barry. “We remain dedicated to our mission of developing novel medicines for central nervous system disorders. While we have initiated preclinical studies to evaluate simufilam’s potential as a treatment for TSC-related epilepsy, we maintain ongoing strategic expense management efforts.”

Eric Schoen, Chief Financial Officer of Cassava commented, “We remain focused on the interests of Cassava shareholders and are committed to enhancing shareholder value. Cassava is well-capitalised with approximately US$128.6 million in cash and cash equivalents as of December 31, 2024.”

Source:

Cassava Sciences. Cassava Sciences Reports Topline Phase 3 REFOCUS-ALZ Data. [Date Accessed 04/04/2025]. www.cassavasciences.com/news-releases/news-release-details/cassava-sciences-reports-topline-phase-3-refocus-alz-data