SP34-2

Expanded characterization of CD3-binding antibodies includes identification of antibodies that bind regions of CD3 that are distinct from commonly used molecules Robust proof-of-concept study demonstrates T-cell engagers that potently eliminate cancer cells with minimal cytokine release VANCOUVER, British Columbia--(BUSINESS WIRE)-- AbCellera (Nasdaq: ABCL) today announced the release of new data on its T-cell engager (TCE) platform at the Society for Immunotherapy of Cancer (SITC) 37th Annual Meeting, to be held virtually and at the Boston Convention & Exhibition Center from November 8 to 12, 2022. AbCellera’s poster presentation describes the expansion, further characterization, and validation of a diverse panel of CD3-binding antibodies that can be used to develop T-cell engagers for cancer treatments. “The robust data package we are presenting at SITC demonstrates that our panel includes antibodies that are distinct from molecules commonly used for CD3 T-cell engager development,” said Bo Barnhart, Ph.D., VP, Translational Research at AbCellera. “By combining this panel with the OrthoMab bispecifics platform and high-throughput antibody analytics, we have shown that we can rapidly identify developable T-cell engagers that balance potent cytotoxicity and low cytokine release.” CD3 T-cell engagers are bispecific antibodies that redirect T cells to kill tumor cells. Developing effective T-cell engagers requires two parental antibodies: a CD3-binding arm that fine-tunes T-cell activation and a tumor-binding arm with high specificity for cancer cells. Pairs of parental antibodies that work well together are rare, creating a need for diverse panels of developable antibodies that can be combined and tested at scale to find optimal clinical candidates. To address the paucity of anti-CD3 antibodies for TCEs, AbCellera used its integrated antibody discovery, characterization, and engineering technologies to discover and validate an extensive panel of fully human CD3-binding antibodies. New data presented at SITC includes epitope binning analysis, revealing antibodies with species cross-reactivity that bind epitopes distinct from commonly used parental antibodies, such as SP34-2. AbCellera also conducted a second discovery campaign strategically designed to enhance the number of cross-reactive antibodies in the panel, resulting in hundreds of additional unique antibody sequences to be characterized. Developing bispecific antibodies that potently eliminate cancer cells without inducing toxicity has been a significant challenge limiting T-cell engager development. In a proof-of-concept study, AbCellera used its OrthoMabTM bispecifics platform to create CD3 x EGFR T-cell engagers. High-throughput functional and biophysical assays identified potent tumor-cell killing T-cell engager molecules that maintained low levels of cytokine production without the need for further engineering or optimization. “We debuted our T-cell engager platform at the AACR annual meeting in April of this year, and in less than six months, we have greatly expanded the data package supporting this platform,” said Murray McCutcheon, Ph.D., Senior VP, Corporate Development at AbCellera. “The remarkable progress demonstrates the speed of AbCellera’s antibody discovery engine, the quality of the antibodies in our T-cell engager panel, and the potential impact it has for partners looking to accelerate development of new cancer treatments.” Details on AbCellera’s presentation at SITC are as follows: Title: Streamlining T-cell engager development with a diverse panel of fully human CD3-binding antibodies, bispecific engineering technology, and an integrated discovery engine Poster Number: 1196 Date and Time: Friday, November 11, 9:00 a.m. to 8:30 p.m. ET Location: Boston Convention & Exhibition Center, Hall C or online at The poster is available for viewing here. About AbCellera Biologics Inc. AbCellera is a technology company that searches, decodes, and analyzes natural immune systems to find antibodies that its partners can develop into drugs to prevent and treat disease. AbCellera partners with drug developers of all sizes, from large pharmaceutical to small biotechnology companies, empowering them to move quickly, reduce cost, and tackle the toughest problems in drug development. For more information, please visit AbCellera Forward-looking Statements This press release contains forward-looking statements, including statements made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. The forward-looking statements are based on management’s current beliefs and assumptions and on information currently available to management. 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Source: AbCellera Biologics Inc.