Acumen Pharmaceuticals has announced a strategic collaboration with JCR Pharmaceuticals to develop next-generation Alzheimer's disease therapies that combine targeted antibody treatment with enhanced brain delivery technology. The partnership leverages Acumen's expertise in amyloid beta oligomer-selective antibodies with JCR's proprietary blood-brain barrier-penetrating J-Brain Cargo® platform.
The collaboration addresses a critical challenge in neurological drug development: the blood-brain barrier's protective function that limits therapeutic delivery to the brain. While this barrier protects against harmful substances, it significantly restricts the penetration of larger molecules like biologics into brain tissue at therapeutic concentrations.
Combining Complementary Technologies
The partnership will focus on developing Enhanced Brain Delivery (EBD™) therapies using Acumen's sabirnetug or additional novel amyloid beta oligomer (AβO)-selective antibodies combined with JCR's transferrin receptor-targeting technology. This approach aims to create treatments with enhanced efficacy, safety, and convenience for Alzheimer's disease patients.
"We are thrilled to enter into this collaboration pairing Acumen's AβO-targeted antibody expertise with JCR's validated proprietary BBB-penetrating technology after completion of a number of feasibility experiments with JCR over the past year," said Daniel O'Connell, Chief Executive Officer of Acumen. The collaboration follows more than one year of engagement to assess technical feasibility and profile development candidates.
JCR's J-Brain Cargo® technology represents a proprietary drug delivery system that efficiently delivers therapeutics to target tissues, including the central nervous system, through receptor-mediated transcytosis. The platform is applicable to various modalities including antibodies, enzymes, oligonucleotides, lipid nanoparticles, gene and cell therapy, peptides and decoy receptors.
Proven Clinical Foundation
Acumen's lead program, sabirnetug (ACU193), provides the clinical foundation for this collaboration. The humanized monoclonal antibody is the first to demonstrate selective target engagement of AβOs in Alzheimer's disease patients. These soluble and highly synaptotoxic forms of amyloid beta accumulate early in Alzheimer's disease and serve as persistent triggers of synaptic dysfunction and neurodegeneration.
The Phase 1 INTERCEPT-AD clinical trial demonstrated that sabirnetug was generally well-tolerated with low overall rates of ARIA-E (amyloid-related imaging abnormalities-edema). The trial showed dose- and exposure-dependent target engagement with AβOs and statistically significant amyloid plaque reduction compared to placebo at higher dose multiple-ascending dose cohorts.
Sabirnetug has received Fast Track designation from the U.S. Food and Drug Administration for the treatment of early Alzheimer's disease. The drug is currently being evaluated in ALTITUDE-AD, a Phase 2, multi-center, randomized, double-blind, placebo-controlled clinical trial that enrolled 542 patients with early Alzheimer's disease at sites in the United States, Canada, the European Union and the United Kingdom. Enrollment completion was announced in March 2025, with topline results including efficacy and safety data planned for late 2026.
Validated Delivery Platform
JCR's transferrin receptor binding platform includes a library of both scFv (single chain variable fragment antibodies) and VHHs (variable heavy domain antibodies), molecules related to the full IgG used in their approved therapy, IZCARGO®. The first drug developed based on J-Brain Cargo® technology is IZCARGO® (pabinafusp alfa), which is approved in Japan for the treatment of a lysosomal storage disorder and exhibits an established safety profile.
The collaboration will investigate not only sabirnetug but also other oligomer-specific antibodies in Acumen's library to establish lifecycle opportunities. A preclinical candidate data package, inclusive of a non-human primate study, is expected in early 2026, at which point Acumen has an exclusive right to exercise its option to develop up to two development candidates.
Financial Structure and Timeline
Under the agreement terms, JCR will receive an upfront payment and will be eligible for an additional option payment should Acumen exercise its exclusive option to develop up to two development candidates. JCR will also be eligible to receive future development, commercialization and sales milestone payments, as well as single digit percentage royalties on sales of any products that emerge from the collaboration.
The partnership represents a strategic approach to addressing the significant unmet need in Alzheimer's disease treatment by combining validated technologies from both companies. O'Connell noted that following "a robust search and evaluation process assessing multiple technologies in the space," Acumen selected JCR as "an established leader who has successfully developed an approved therapy in Japan."
