Medigene AG: Identification of ten novel tumor-specific antigens immunogenic for T cells

Medigene AG: Identification of ten novel tumor-specific antigens immunogenic for T cells

Poster presentation at virtual AACR Annual Meeting, 10-15 April 2021

Planegg/Martinsried and Montréal (pta/10.04.2021/14:30) 10 April 2021. Medigene AG (Medigene, FSE: MDG1, Prime Standard), a clinical stage immuno-oncology company focusing on the development of T cell immunotherapies, today presents the screening and identification of novel immunogenic tumor-specific antigens (TSAs) derived from non-coding regions of the human genome at the American Association for Cancer Research Virtual Annual Meeting (AACR) 2021. The poster can be found on Medigene's website: https://www.medigene.com/technologies/abstracts

Significant efforts are being dedicated worldwide to identifying novel TSAs as targets for cancer immunotherapy. In this respect, not only known proteins but also non-coding genetic regions of cells are studied as sources of peptides that can be presented by HLA molecules at the surface of tumor cells and be recognized by T cell receptors (TCRs). Such TSAs can provide new targets that allow improved discrimination between cancer cells and healthy tissues by T cells.

Under a collaboration agreement with IRICoR and the Institute for Research in Immunology and Cancer (IRIC) of the Université de Montréal, Canada, Medigene gained access to 47 potential TSAs presented by one of five common HLA types that were identified as novel peptides eluted from the HLA molecules of tumor cells. These peptides were found to be shared among specimens of several patients with solid tumors of different origin, such as ovarian, breast, and lung cancer, but were not detected in healthy tissues, giving them the character of TSAs for TCRs.

Medigene's high-throughput screening technology identified ten peptides as immunogenic and able to induce specific T cell responses. One or more immunogenic peptides were found for each of the five analyzed HLA types. TCRs of T cell clones recognizing these novel peptides were determined by gene sequencing and their characterization is ongoing.

Prof. Dolores Schendel, Chief Executive Officer and Chief Scientific Officer at Medigene: "We are very proud to demonstrate that our high-throughput functional T cell screening approach proves to be a key tool in development of TCR-based cancer immunotherapies that can target a new class of TSAs based on peptides derived from non-coding genetic regions expressed by tumor cells. Our technologies allowed new peptide-HLA combinations to be rapidly defined that have the potential to broaden TCR diversity for patients with different HLA types whose tumors present these novel peptides.

Experiments are ongoing for individual TCRs to determine their suitability for future clinical development of TCR-T-based immunotherapy. We look forward to learning whether this novel class of TSAs will form a strong basis for T cell-based immunotherapies that can reach more patients who are in need of new therapeutic options to treat cancer."

Dr. Steven Klein, Vice-President, Business Development at IRICoR: "Our ongoing collaboration with Medigene is very important for IRICoR and for the researchers at IRIC who identified these TSAs. The demonstration by Medigene of the immunogenicity of these solid tumor TSAs is an important milestone in the development of new TSA-based immunotherapies. IRICoR continues to invest in the identification of novel immunogenic TSAs in both solid and liquid tumors, and we expect to develop additional partnerships around this TSA discovery platform."