Novel specific TCRs targeting KRASG12V-related cancers.

e14528 Background: KRAS mutations act as oncogenic drivers in a variety of tumors, such as pancreatic, colorectal and lung cancer. Among these, the KRAS G12V mutation, being one of the most common mutations, is associated with adverse outcomes in patients. KRAS has been regarded as an “undruggable” target, and no clinical trials targeting tumors carrying shared KRAS G12V mutation have been initiated. Notably, KRAS G12D specific TCR-T has shown high effectiveness, including the regression of metastases in patients with pancreatic cancer. Therefore, TCR-engineered T cells could be a promising strategy for the treatment of solid tumors harboring G12V mutation. Methods: We have developed an innovative approach to rapidly and sensitively identify natural TCRs from single T cell derived from patients using CorreGene’s Single T cell TCR Cloning platform, thus obviating the requirement for NGS sequencing and TCR gene synthesis. Additionally, natural TCRs can be refined with SMART-TCR system, utilizing T cell reporter cell lines to construct a high-throughput T-cell Display Platform for functional screening of TCRs. This system is meticulously designed to enrich TCRs with superior potency and specificity from a natural TCR mutation library. We performed a thorough assessment of each TCR identified, evaluating them across both in vitro and in vivo settings. Results: In the present study, we identified three natural TCRs from patients' TILs, designated as KVA11-N01, KVA11-N02 and KVA11-N04 respectively, that specifically recognized the HLA-A*11:01-restricted KRAS G12V epitope. KVA11-N01 exhibited lower affinity and potency, prompting us to develop an affinity-optimized variant, KVA11-M01-231, using the SMART-TCR system. For comparison, we used the murine TCR TRAV3-301/BV401, identified by NCI from HLA-A11:01 transgenic mice immunized with KRAS G12V 7-16 , as a benchmark. Three of our TCRs, including KVA11-N02, KVA11-N04 and the engineered KVA11-M01-231, outperformed TRAV3-301/BV401 in both in vitro and in vivo assays. These three TCRs exhibited excellent expression intensity and stability on T cells, and notably, their IFN-γ release potency surpassed that of TRAV3-3*01/BV4*01. Furthermore, in vivo experiments confirmed the significant tumor suppression efficacy of our TCRs in a tumor-bearing mouse model, showing enhanced tumor growth inhibition compared to TRAV3-301/BV401. TCRs from Corregene’s platform exhibited exceptional specificity, with no allo-reactivity, no reaction to KRAS G12V -negative cell lines, and no off-target effects. Additionally, all our TCRs demonstrates favorable tolerance in mice during in vivo studies. Conclusions: TCRs via Corregene’s Single T cell TCR Cloning platform and SMART-TCR system showed significantly excellent anti-tumor activities with great specificity and offers a promising solution for the treatment of KRAS G12V -related cancers.