Neon Therapeutics, Inc. presented updated data at the Society for Immunotherapy of Cancer's (SITC) 34th Annual Meeting in National Harbor, MD. Neon announced updated results (August 2019 data cut) from the ongoing, multicenter Phase 1b clinical trial evaluating NEO-PV-01, Neon's personal neoantigen vaccine candidate, in combination with OPDIVO (nivolumab) in patients with advanced or metastatic melanoma, smoking-associated non-small cell lung cancer (NSCLC) and bladder cancer. Across all three distinct tumor types, results demonstrated prolonged and consistent improvements in progression-free survival (PFS) and overall survival (OS) that compare favorably to that observed with checkpoint inhibitor monotherapy, based on historical benchmark data. Further, neoantigen-specific immune responses and epitope spread to RECON -predicted targets were associated with longer PFS and major pathological responses post-administration of NEO-PV-01 in melanoma patients were also associated with longer PFS. The safety data for NT-001 were consistent with the safety profile for OPDIVO monotherapy. These updated results come from 82 patients who received at least one dose of OPDIVO in the Phase 1b NT-001 trial. The NT-001 trial was initiated in November 2016 and completed enrollment in July 2018. NEO-PTC-01: Advanced Process Development Supports Clinical Trial Application Filing in Europe by End of 2019. Neon continues to advance its preclinical and process development work for NEO-PTC-01, its personal neoantigen-targeted T cell therapy candidate consisting of multiple T cell populations targeting the most therapeutically relevant neoantigens from each patient's tumor. NEO-PTC-01 leverages Neon's RECON bioinformatics platform to individually select a set of neoantigen targets for each patient, and NEO-STIM, its proprietary process to directly prime, activate and expand neoantigen-targeting T cells ex vivo. Neon believes that this approach will allow NEO-PTC-01, a non-engineered T cell product that leverages peripheral blood mononuclear cells (PBMCs) as its starting material, to specifically target each patient's individual tumor with T cells that can drive a robust and persistent anti-tumor response. In the update presented November 8, 2019 at SITC, Neon demonstrated that it can reproducibly generate a potent T cell product from PBMCs of melanoma patients, as well as at therapeutic scale using a healthy donor sample. This process development work showed that NEO-PTC-01 induced multiple CD8 and CD4 T cell responses from both the memory and na ve T cell compartments. The induced T cell responses were mutant-specific, showed a polyfunctional profile and had a central and effector memory phenotype. The induced T cell responses had cytotoxic capability, shown by the recognition of antigen-expressing tumor cell lines. Importantly, NEO-PTC-01 induced T cell cultures that directly recognized autologous tumor digest. Neon is focusing the initial clinical development of NEO-PTC-01 in patients with solid tumors that are refractory to checkpoint inhibitors. Neon expects to file a clinical trial application, or CTA, in Europe by the end of 2019 to evaluate NEO-PTC-01 in the solid tumor setting.