Figure 1. . Timeline of clinical trials for glioma using immunotherapy.

A search for ‘immunotherapy’ and ‘glioma’ in the ClinicalTrials.gov database (March 2015) yields a list of 61 clinical trials: 14 with dendritic cell vaccines, 9 testing synthetic peptide vaccines, 8 using autologous T-cell transfer, 6 gene therapy, 4 with tumor cell lysate vaccine combined with T-cell transfer, 2 with autologous NK or NKT cell transfer, 2 with allogeneic T-cell transfer, 4 targeting immunosuppressive checkpoints and 7 using other immune treatment strategies. Limitations of the search engine may not allow a comprehensive listing; nonetheless, the graph illustrates the extensive interest in antiglioma vaccines and an emerging trend of testing immunosuppressive checkpoints.

NK: Natural killer; NKT: NK T cell.