Vaccinex’s Next Generation ActivMAb® Technology Published in mAbs, a Leading Biotech Journal, and Validated in OmniAb Proof-of-Concept Collaboration

Application is based on proprietary poxvirus system that enables Hard-to-Drug Complex Proteins to be expressed at high levels in their “native conformation” so as to efficiently induce and select specific antibody-producing cells

Successfully applied in proof-of-concept evaluation by OmniAb to select antibodies against ion channel and chemokine receptor proteins in transgenic animals

ROCHESTER, N.Y., Sept. 28, 2023 (GLOBE NEWSWIRE) — Vaccinex, Inc. (Nasdaq: VCNX), a clinical-stage biotechnology company pioneering a differentiated approach to treating Alzheimer’s and other neurodegenerative diseases through the inhibition of SEMA4D, announces a new publication in the journal mAbs describing a novel way in which its proprietary ActivMAb® poxvirus platform can enable the presentation of high complexity, hard-to-drug proteins as targets for antibody discovery.

The article, titled “Use of poxvirus display to select antibodies specific for complex membrane antigens” provides an overview of how Vaccinex created an elegant, poxvirus system modified for safety that can readily express high levels of hard-to-drug protein targets, such as G-protein coupled receptors (GPCRs) and ion channels, on the natural external membrane of virus in a “native”, properly-oriented conformation. This allows a consistent supply of protein to be readily available as antibody immunogens and greatly facilitates the screening, selection and affinity improvement of antibody candidates.

“We believe this new “Antigen Virus” application is a powerful complement to Vaccinex’ ActivMAb platform and we are pleased for this work to be published in mAbs. After rigorous evaluation, using a variety of different, complex protein targets including the SARS-CoV-2 Spike protein and a number of GPCRs, we believe that the ActivMAb system can readily generate functional and properly folded complex proteins that can be used for selection of novel, high-value, antibody therapeutics,” said Ernest Smith, Ph.D., Senior Vice President of Research and Chief Scientific Officer of Vaccinex.

This novel application of Vaccinex’s ActivMAb technology was successfully used with OmniAb, Inc.’s high-throughput B cell screening and proprietary in vivo immunization platform. OmniAb was able to select antibodies against challenging multipass membrane targets (ion channel Kv1.3 and a chemokine receptor), that were displayed on ActivMAb antigen viruses.

Dr. Smith concluded, “Early results with our industry collaborators have been successful where alternative approaches have failed. We look forward to making this new ActivMAb application broadly available to biopharmaceutical partners to accelerate development of novel, high-value therapeutics.”

Dr. Smith has been invited to present this exciting work at CHI’s 11th Annual Discovery on Target (DOT) conference in Boston, which takes place from September 25-28, 2023. The team will be making both podium and poster presentations at this preeminent event.

About ActivMAb®
ActivMAb is a proprietary mammalian cell-based antibody discovery platform developed by Vaccinex with unique capabilities for multi-pass membrane targets such as G-protein-coupled receptors (GPCRs). The ActivMAb technology has multiple applications including: complex membrane antigen presentation and expression, antibody and antigen discovery, directed evolution and protein optimization.

The first clinical candidate selected through use of this technology (SRF114, a fully human monoclonal antibody targeting CCR8 for the potential treatment of solid tumors), entered development in a Phase 1/2 study sponsored by our licensee, Surface Oncology, recently acquired by Coherus Biosciences, Inc. The technology and its potential applications for drug discovery against complex membrane protein targets have been described in several publications and is the focus of collaborations with leading biopharmaceutical companies.

About Vaccinex Inc. 
Vaccinex, Inc. is pioneering a differentiated approach to treating slowly progressive neurodegenerative diseases and cancer through the inhibition of semaphorin 4D (SEMA4D). The Company’s lead drug candidate, pepinemab, is designed to block SEMA4D, a potent biological effector that is believed to trigger damaging inflammation in chronic diseases of the brain and inhibit immune infiltration and activation in tumors. In neurodegenerative diseases, pepinemab is being studied as a monotherapy in the Phase 1/2a SIGNAL-AD study in Alzheimer’s Disease, with ongoing exploration of potential Phase 3 development in Huntington’s disease. In oncology, pepinemab is being evaluated in combination with KEYTRUDA® in the Phase 1b/2 KEYNOTE-B84 study in recurrent or metastatic head and neck cancer (HNSCC) and in combination with BAVENCIO® in a Phase 1b/2 study in patients with metastatic pancreatic adenocarcinoma (PDAC). The oncology clinical program also includes several investigator-sponsored studies in solid tumors including breast cancer and melanoma.

Forward Looking Statements
To the extent that statements contained in this presentation are not descriptions of historical facts regarding Vaccinex, Inc. (“Vaccinex,” “we,” “us,” or “our”), they are forward-looking statements reflecting management’s current beliefs and expectations. Such statements include, but are not limited to, statements about our the applicability and ability of the “Antigen Virus” application of the ActivMab® platform, plans, expectations and objectives with respect to, the expected timeline for disclosure of results at scientific conferences or through publications, and other statements identified by words such as “believes,” “being,” “may,” “will,” “appears,” “expect,” “continue,” “estimate,” “ongoing,” “potential,” “prevents,” “suggest”, and similar expressions or their negatives (as well as other words and expressions referencing future events, conditions, or circumstances). Forward-looking statements involve substantial risks and uncertainties that could cause the outcome of our research and pre-clinical development programs, clinical development programs, future results, performance, or achievements to differ significantly from those expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, uncertainties inherent in the execution, cost and completion of preclinical studies and clinical trials, that interim and preliminary data may not be predictive of final results and does not ensure success in later clinical trials, uncertainties related to regulatory approval, risks related to our dependence on our lead product candidate pepinemab, the impact of the COVID-19 pandemic, the possible delisting of our common stock from Nasdaq if we are unable to regain compliance with the Nasdaq listing standards, and other matters that could affect our development plans or the commercial potential of our product candidates. Except as required by law, we assume no obligation to update these forward-looking statements. For a further discussion of these and other factors that could cause future results to differ materially from any forward-looking statement, see the section titled “Risk Factors” in our periodic reports filed with the Securities and Exchange Commission (“SEC”) and the other risks and uncertainties described in the Company’s annual year-end Form 10-K and subsequent filings with the SEC.

Investor Contact                                        
John Mullaly                                        
LifeSci Advisors, LLC                                
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