Reprints and permissions information is available at www.nature.com/reprints. Data availability All sequencing data from this study have been deposited in the National Center for Biotechnology Information Gene Expression Omnibus (GEO) and are accessible through the GEO Series accession code GSE122713. All other relevant data are available from the corresponding author on request.

Neoantigens, which are derived from tumour-specific protein-coding mutations, are exempt from central tolerance, can generate robust immune responses1,2 and can function as bona fide antigens that facilitate tumour rejection3. Here we demonstrate that a strategy that uses multi-epitope, personalized neoantigen vaccination, which has previously been tested in patients with high-risk melanoma4–6, is feasible for tumours such as glioblastoma, which typically have a relatively low mutation load1,7 and an immunologically ‘cold’ tumour microenvironment8. We used personalized neoantigen-targeting vaccines to immunize patients newly diagnosed with glioblastoma following surgical resection and conventional radiotherapy in a phase I/Ib study. Patients who did not receive dexamethasone—a highly potent corticosteroid that is frequently prescribed to treat cerebral oedema in patients with glioblastoma—generated circulating polyfunctional neoantigen-specific CD4+ and CD8+ T cell responses that were enriched in a memory phenotype and showed an increase in the number of tumour-infiltrating T cells. Using single-cell T cell receptor analysis, we provide evidence that neoantigen-specific T cells from the peripheral blood can migrate into an intracranial glioblastoma tumour. Neoantigen-targeting vaccines thus have the potential to favourably alter the immune milieu of glioblastoma.

Key Points Question Is tumor mutation burden (TMB) associated with improved outcomes of programmed cell death–1 (PD-1)/programmed death ligand–1 (PD-L1) inhibition across PD-L1 expression levels in non–small cell lung cancer (NSCLC)? Findings In this cohort study of 1552 patients with NSCLC, the group with high TMB had improved response rates and survival after receiving PD-1/PD-L1 inhibition therapy across PD-L1 expression subgroups compared with the group with low TMB. High TMB levels were associated with increased CD8-positive T-cell infiltration and distinct immune response gene expression signatures. Meaning These findings suggest that in NSCLC, a high number of nonsynonymous tumor mutations is associated with immune cell infiltration and inflammatory T-cell expression signatures, leading to increased sensitivity to PD-1/PD-L1 inhibition across PD-L1 expression subgroups.