Gubens MA, et al. - Given that combination therapy with pembrolizumab plus ipilimumab was assessed in patients with previously treated advanced non-small-cell lung cancer (NSCLC) in the phase 1/2 KEYNOTE-021 study, researchers report outcomes from dose-finding and dose-expansion cohorts. The eligible patients were those with histologically/cytologically confirmed advanced NSCLC and treatment failure on ≥1 prior systemic therapy (platinum-based chemotherapy or targeted therapy for patients with EGFR/ALK aberrations). Included were 51 patients; ≥2 prior lines of therapy were received by 71%. Antitumor activity was displayed by pembrolizumab plus ipilimumab in patients with heavily pretreated advanced NSCLC but this combination therapy was related to treatment-related adverse events (64%). Rates of grade 3–5 treatment-related adverse events were 29%, and of immune-mediated adverse events and infusion reactions were 42% with pembrolizumab 2 mg/kg plus ipilimumab 1 mg/kg.