Introduction: Lung cancer is the leading cancer-related cause of death worldwide. The introduction of immune checkpoint inhibitors (ICIs) for the treatment of lung cancer has significantly improved the outcome of these patients. Pembrolizumab, a monoclonal IgG4-kappa antibody against programmed-death-1 (PD-1) protein, nowadays represents a standard of care for NSCLC patients. Although it has a favorable toxicity profile, some immune-related adverse events (irAEs) can be life-threatening, therefore its knowledge may help to optimize the care of these patients.Areas covered: The authors review data regarding the efficacy and safety of pembrolizumab from the most relevant clinical trials as well as toxicities reported in the clinical use. Special considerations of use in special populations will be noted. Finally, its toxicity profile will be compared with other ICIs used in NSCLC.Expert opinion: In the scenario of NSCLC, pembrolizumab shows a favorable safety profile with less than 10% serious immune-related adverse events (irAEs) when used in monotherapy and without adding relevant extra-toxicity to chemotherapy when used in combination. Monotherapy with pembrolizumab is associated with better health-related quality of life than chemotherapy. Early recognition and appropriate treatment of irAEs is of prime importance as most are reversible if correctly managed. Rechallenge with pembrolizumab is frequently feasible.
Keywords: Non-small cell lung cancer (NSCLC); PD-1; immune- related adverse effects (irAEs); pembrolizumab.