Acumen Pharmaceuticals reported significant progress in its Alzheimer's disease pipeline during the second quarter of 2025, with the company's lead candidate sabirnetug advancing through Phase 2 trials and a new strategic partnership expanding its therapeutic portfolio. The clinical-stage biopharmaceutical company expects topline results from its pivotal ALTITUDE-AD study in late 2026, while simultaneously developing next-generation brain delivery technologies through a collaboration with JCR Pharmaceuticals.
ALTITUDE-AD Trial Demonstrates Operational Excellence
The Phase 2 ALTITUDE-AD study has successfully enrolled 542 individuals with early Alzheimer's disease across multiple sites in the United States, Canada, the European Union, and the United Kingdom. The randomized, double-blind, placebo-controlled trial is evaluating sabirnetug administered once every four weeks compared to placebo in slowing cognitive and functional decline.
Acumen implemented innovative operational strategies that significantly improved trial efficiency and reduced costs. The company introduced a two-step screening process using plasma pTau217 biomarker assay testing, which reduced total screening costs by approximately 40% across U.S. and Canadian sites. This approach helped achieve strong enrollment rates while reducing unnecessary amyloid PET scans and lumbar puncture procedures for potential participants.
Sabirnetug Shows Superior Selectivity Profile
New data presented at the Alzheimer's Association International Conference demonstrated sabirnetug's exceptional selectivity for toxic amyloid beta oligomers (AβOs). Comprehensive surface plasmon resonance testing revealed that sabirnetug achieved the highest binding affinities to AβO preparations among the monoclonal antibodies tested. The antibody demonstrated 8,750-fold selectivity for Aβ1-42 stabilized oligomers over Aβ1-40 monomers, supporting its mechanism of action and selectivity for AβOs.
"We believe, with this portfolio, that we are well-positioned to deliver next-generation treatment options for early Alzheimer's disease," said Daniel O'Connell, Chief Executive Officer of Acumen.
Strategic Partnership Expands Pipeline
In July 2025, Acumen announced a collaboration, option and license agreement with JCR Pharmaceuticals to develop an oligomer-targeted Enhanced Brain Delivery (EBD™) therapy for Alzheimer's disease. The partnership combines sabirnetug or additional novel AβO-selective antibodies with JCR's blood-brain barrier-penetrating technology (J-Brain Cargo®).
The companies have collaborated for more than a year conducting feasibility work to assess the combination of JCR's transferrin targeting technology with Acumen's AβO-targeting antibodies. Acumen expects non-clinical data to support the development of an EBD therapy in early 2026, at which point the company has an exclusive right to exercise its option to develop up to two development candidates as part of the partnership.
Financial Position Supports Extended Operations
Acumen reported cash, cash equivalents and marketable securities of $166.2 million as of June 30, 2025, compared to $197.9 million as of March 31, 2025. The company expects this cash position to support current clinical and operational activities into early 2027.
Research and development expenses increased to $37.1 million for the three-month period ended June 30, 2025, compared to $19.5 million for the same period in 2024. The increase was primarily due to manufacturing and materials costs, as well as CRO costs associated with the ALTITUDE-AD clinical trial. Net loss was $41.0 million for the second quarter of 2025, compared to $20.5 million for the same period in 2024.
Targeting Toxic Oligomers in Alzheimer's Disease
Sabirnetug is a humanized monoclonal antibody discovered and developed based on its selectivity for soluble amyloid beta oligomers, which are a highly toxic and pathogenic form of Aβ relative to Aβ monomers and amyloid plaques. Soluble AβOs have been observed to be potent neurotoxins that bind to neurons, inhibit synaptic function and induce neurodegeneration.
The drug has been granted Fast Track designation for the treatment of early Alzheimer's disease by the U.S. Food and Drug Administration. By selectively targeting toxic soluble AβOs, sabirnetug aims to address the hypothesis that soluble AβOs are an early and persistent underlying cause of the neurodegenerative process in Alzheimer's disease.
