Acumen to Halt Sabirnetug Development After Alzheimer's Trial Misses Main Goal
The company also plans cash conservation and a review of strategic options, with $78.6 million in cash and investments as of Sept. 30.
Stock reaction: ABOS shares were down 86.0% at 10 a.m. ET on Oct. 30, from Oct. 29's close of $2.29. The S&P 500 was down 1.1% over the same span.
Key points
- Sabirnetug missed its primary endpoint at both 35 mg/kg and 50 mg/kg doses in the Phase 2 ALTITUDE-AD trial
- Acumen plans to stop developing sabirnetug, including the open-label extension
- Cash and investments totaled $78.6 million as of Sept. 30
- Q3 2026 net loss was $25.4 million, versus $26.5 million a year earlier
- Market value before the filing was about $165.6 million at $2.29 a share
Acumen Pharmaceuticals (Nasdaq: ABOS) said its lead Alzheimer's drug candidate did not meet the main goal of its Phase 2 trial, and that it will stop developing the drug. The news came in an 8-K filed Friday, Oct. 30, 2026, which attached a press release with initial topline results.
The trial missed its primary goal
The trial, called ALTITUDE-AD, tested sabirnetug in people with early Alzheimer's disease. The primary endpoint was the change from baseline in cognitive and functional decline, measured by the Integrated Alzheimer's Disease Rating Scale at 18 months, compared with placebo. Neither the 35 mg/kg nor the 50 mg/kg dose separated from placebo on that measure.
The trial also failed to reach statistical significance on key secondary endpoints, including the Clinical Dementia Rating, Sum of Boxes. The company said there was no meaningful difference between either sabirnetug arm and the placebo arm. The study enrolled 542 people at sites in the United States, Canada, the European Union and the United Kingdom.
Amyloid results and side effects
The company said sabirnetug was generally well tolerated. Amyloid-related imaging abnormalities, or edema, appeared in about 10% of treated participants. A positron emission tomography analysis showed statistically significant reductions in amyloid plaque load at both doses at week 36 and week 76.
Acumen said it expects to receive additional fluid biomarker and imaging data from the trial in the coming weeks, but does not expect those data to change the trial's efficacy conclusions.
Plans and cash position
Acumen plans to cease development of sabirnetug, including the open-label extension portion of the trial. It also plans to evaluate its strategic options, including its Enhanced Brain Delivery program, and to take steps to implement cash conservation measures. The company said it will explore strategic options to maximize shareholder value.
As of Sept. 30, Acumen had $53.1 million in cash and equivalents and $25.5 million in short-term investments, or $78.6 million combined. Its net loss for the third quarter was $25.4 million, compared with $26.5 million a year earlier. For the 2025 fiscal year, the net loss widened to $121.3 million from $102.3 million.
Before the filing, the company's market value was about $165.6 million, based on 72.3 million shares outstanding as of Oct. 21. The shares closed at $2.29 on Thursday, Oct. 29. Combined cash and investments equal about 47% of that market value.
The filing does not give a dollar figure for the cash conservation measures or a timeline for the strategic review.
Sources
Written with AI from the company's SEC filing and our market data, and checked against those sources before publishing. Our editorial standards.
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