Gaynor, Michael S. Rooney,Lakshmi Srinivasan Correspondence asaf.poran@biontech.us (A.P.), lakshmi.srinivasan@biontech.us (L.S.) In Brief Poran et al. study peripheral blood cells from metastatic melanoma patientsbefore, during, and after treatment withpersonalized neoantigen therapy plusanti-PD-1. The combination of T cellreceptor repertoire proﬁling andimmunophenotyping of blood cellscollected pre-treatment presents a strongpredictor for response to treatment in aminimally invasive manner.Principal Component Analysis for scoring 0.000.250.500.751.00 TimeProgression free survival (PFS)Pre-treatment measurements from patient cohort TCR /g68/g18/g69 Sequencing Flow CytometryGini Coefficient DE50Shannon’s EntropyUnique TCR countsTCR Repertoire Flow Cytometry Naive B cells Naive T cells Memory B cellsEffector/MemoryT cells Poor PC1 score: Shorter PFSFavorable PC1 score: longer PFSMetastatic melanoma patients receiving the personalized neoantigen therapy NEO-PV-01 plus anti-PD-1 Poran et al., 2020, Cell Reports Medicine 1, 100141 November 17, 2020 ª2020 The Author(s). https://doi.org/10.1016/j.xcrm.2020.100141 ll Report Combined TCR Repertoire Proﬁles and Blood Cell Phenotypes Predict Melanoma Patient Responseto Personalized Neoantigen Therapy plus Anti-PD-1 Asaf Poran,1,4,5,*Julian Scherer,1,4Meghan E. Bushway,1Rana Besada,1Kristen N.