ACU401

July 15, 2026: Acumen Pharmaceuticals, Inc. (NASDAQ: ABOS) announced AAIC 2026 (London) presentations on its Enhanced Brain Delivery™ (EBD™) anti-amyloid beta oligomer (AβO) bispecific antibodies developed with JCR Pharmaceuticals’ J-Brain Cargo® transferrin receptor (TfR) platform, plus patient-experience research from its Phase 2 ALTITUDE-AD trial.

EBD/TfR bispecific antibodies (preclinical): In humanized TfR mice, anti-AβO antibody fusion proteins showed substantially higher brain levels vs native anti-AβO antibodies, while maintaining AβO affinity/selectivity; systemic absorption was confirmed after subcutaneous dosing, and constructs bound Aβ species in human AD brain tissue, supporting advancement toward clinical trials.

Non-human primate data: In cynomolgus monkeys, three bispecifics fusing ACU234 with anti-TfR fragments achieved higher brain exposure than ACU234 alone (≥14-fold in frontal cortex after IV dosing). Lead candidate ACU401 reached 22-fold higher frontal cortex exposure at 3 hours and 40-fold at 24 hours, with similar trends in hippocampus and putamen; no hematologic findings suggestive of anemia were observed.

ALTITUDE-AD (Phase 2 sabirnetug/ACU193): Pre-treatment interviews (n=38 participants plus study partners) described memory, functional, and emotional impacts in early symptomatic AD. The Phase 2 trial (NCT06335173; 542 enrolled) has topline results expected in late 2026.