The Keynote-28 trial was a phase Ib basket study evaluating the safety and efficacy of pembrolizumab in different types of solid tumors, involving 26 patients with rGBM with PD-L1 expression >1% on stromal and tumor cells [188]; patients were treated with 10 mg/kg of pembrolizumab every 2 weeks; ORR (the primary endpoint) was 4% (95% CI, 0.1–20.4) and stable disease was observed in 48% of patients. The gene discussed is CD274; the disease is neoplasm.