91P Identification of T cell receptors from tumour-infiltrating lymphocytes cross-reactive to multiple patient-derived metastatic melanoma cell lines using CRISPR-cas9 mediated TCR replacement

PTPRZ1-specific TCR-T cells (TCT-001), administered via a catheter placed during reresection, with or without preceding lymphodepletion.Biomarker studies include advanced MRI and longitudinal immune profiling of blood and cerebrospinal fluid.For engineering patient autologous T cells, we developed a customized non-viral nSMAR DNA vector-based manufacturing process on the CliniMACS Prodigy platform.Results: Benchmarking of our customized manufacturing pipeline confirmed feasibility, reproducibility, and scalability in GMP-compliant settings.Cell engineering consistency of >45% was achieved through electroporation with recovery rates >80%.The cryopreserved product demonstrated optimal post-thaw viability, with validation confirming retained cytotoxic potency.Conclusions: INVENT4GB establishes a first-in-human clinical evaluation of PTPRZ1specific TCR-T in GB.Beyond assessing safety and early efficacy, this trial provides proof-of-concept for a faster, cost-efficient, and clinically translatable non-viral strategy for producing T cell therapies, potentially broadening accessibility and accelerating future development.