Vaccinex to report topline data for SIGNAL-AD Phase 1b/2 trial of Pepinemab in Alzheimer’s Disease at the Alzheimer’s Association International Conference, Philadelphia, July 31, 2024

In This Article:

Vaccinex, Inc.
Vaccinex, Inc.

Pepinemab is believed to block astrocyte reactivity, a key pathology driving Alzheimer’s progression

ROCHESTER, N.Y., July 17, 2024 (GLOBE NEWSWIRE) -- Vaccinex, Inc. (Nasdaq: VCNX), a clinical-stage biotechnology company pioneering a differentiated approach to treating Alzheimer’s disease (AD) and cancer through the inhibition of Semaphorin 4D (SEMA4D), today announced that it will present topline data for its randomized, double-blind, phase 1b/2 SIGNAL-AD study of pepinemab treatment for Alzheimer’s disease at the Alzheimer’s Association International Conference in Philadelphia, July 28- Aug 1, 2024. Eric Siemers, MD, Principal Investigator, will present results of the study in a Featured Research Session.

Presentation title: Results of SIGNAL-AD, a randomized, phase 1b/2 trial to evaluate safety and efficacy of targeting reactive astrocytes with pepinemab, SEMA4D blocking antibody, in people with MCI or mild Alzheimer’s dementia

Presenter: Eric Siemers, MD

Featured Research Session: Glial biomarkers and Alzheimer’s disease therapeutics

Date: Wednesday July 31st, 2024. 9:00 AM EST.

Venue: Ballroom A, Pennsylvania Convention Center, 1101 Arch St., Philadelphia, PA 19107, USA

What can we expect to learn from results of this study?

  • Vaccinex scientists discovered and published that SEMA4D, a molecule that binds to high affinity plexin-B1 receptors predominantly expressed on astrocytes in the brain, is highly upregulated on stressed or damaged neurons during progression of Alzheimer’s Disease (AD)

  • Astrocytes, which are key brain cells that support the health and function of neurons, undergo substantial changes in morphology and gene expression when SEMA4D binds to their plexin-B1 receptors. As a result, they switch from normal supportive functions to neurotoxic inflammatory activity that is believed to aggravate and accelerate progression of AD.

  • The Company’s hypothesis, which is being tested in the SIGNAL-AD study, is that treating with pepinemab antibody that binds SEMA4D can block signaling through its receptor on astrocytes and slow or prevent the damaging consequences of astrocyte activation.

  • The Company has previously reported that antibody blockade of SEMA4D appears to protect healthy astrocyte functions and to slow disease progression in patients with early manifest Huntington’s disease by several different biomarker and clinical measures. An important goal of the present study is to determine whether pepinemab treatment is effective at one or more defined stages of AD progression.

  • Key outcomes of the SIGNAL-AD study will include safety and tolerability and the impact of pepinemab treatment on brain metabolic activity determined by FDG-PET and astrocyte reactivity as detected by plasma levels of glial fibrillary acidic protein (GFAP), a molecule known to be released into blood by reactive astrocytes and believed to be a key biomarker of disease progression.

  • Deposition of Aβ amyloid in the brain is currently the earliest recognized event in the pathologic cascade leading to AD. Aggregates of Aβ are believed to trigger a series of subsequent events, including astrocyte reactivity and formation of toxic tau tangles in neurons, believed to be key drivers of neurodegeneration. It is, therefore, of considerable interest to determine whether blocking SEMA4D-induced astrocyte reactivity might also slow disease progression as evidenced by increasing plasma levels of phosphorylated tau peptide (p-tau 217), a biomarker released into blood during formation of tau tangles in neurons.

  • The Company believes that the prevalence of AD (6 million people diagnosed with AD in the US alone) and current concerns about the limitations of treatment with approved anti-Aβ amyloid antibodies such as Leqembi™ (lecanemab) or Kisunla™ (donanemab) could make pepinemab, if approved, attractive as either an alternative for patients at high risk for adverse events related to treatment with Leqembi™ or Kisunla™, or as a complementary treatment to further enhance the benefit of anti-Aβ antibodies to patients. In this regard, it is important that pepinemab has a very different mechanism of action than anti-Aβ antibodies. Pepinemab has, to date, been well-tolerated in clinical trials that enrolled a total of more than 600 patients.