Immuno-oncology agents currently approved or in clinical trials may afford the most immediate benefit, particularly for patients with C-GBM tumors, including agents targeting PD-1 (nivolumab, pembrolizumab), TIGIT (tiragolumab), CD27 (varlilumab), or STAT3 (WP-1066). The gene discussed is PDCD1; the disease is glioblastoma.