Cassava Sciences Abandons Alzheimer's Program as Simufilam Fails Second Phase 3 Trial

Simufilam's Late-Stage Failure Leads to Program Discontinuation

Cassava Sciences has announced the discontinuation of its Alzheimer's disease program following the failure of simufilam in a second phase 3 clinical trial. The Texas-based biotech company reported that the ReFocus-ALZ study missed its prespecified co-primary, secondary, and exploratory biomarker endpoints, leading to the decision to halt all development efforts for simufilam in Alzheimer's disease.

The ReFocus-ALZ trial, which had already been discontinued after an initial phase 3 failure reported late last year, completed 52-week follow-ups for all patients, with many reaching 76-week assessments. However, the additional data failed to demonstrate any treatment benefit for patients receiving simufilam.

Clinical Trial Results and Implications

The co-primary endpoint data from the ReFocus-ALZ trial showed no significant improvement in cognitive or functional outcomes for patients treated with simufilam compared to placebo. On the ADAS-COG12 scale, where lower scores indicate less cognitive impairment, patients in the simufilam cohorts saw increases of 4.97 and 5.26 points, while the placebo group increased by 4.70 points. Similarly, on the ADCS-ADL scale measuring functional impairment, simufilam-treated patients experienced declines of 6.27 and 6.43 points, compared to a 5.32-point decline in the placebo group.

Cassava Sciences CEO Rick Barry stated, "These results were unambiguous. Cassava will discontinue all efforts to develop simufilam for Alzheimer's disease and we expect to phase out the program by the end of Q2 2025."

Company Strategy and Financial Outlook

In light of the simufilam failure, Cassava Sciences is shifting its focus to other potential applications for the drug. The company has recently entered into a license agreement and begun preclinical studies to evaluate simufilam as a potential treatment for tuberous sclerosis complex-related epilepsy.

Despite this setback, Cassava remains financially stable, reporting $128.6 million in cash and cash equivalents at the end of the previous year. The company plans to maintain its "ongoing strategic expense management efforts" while investing in the new preclinical studies.

The announcement of simufilam's failure and the subsequent discontinuation of the Alzheimer's program had an immediate impact on Cassava's stock price, which fell more than 20% to $2.20 when markets opened on Tuesday, down from Monday's closing price of $2.78.