To observe the clinical efficacy and safety of tislelizumab injection in the treatment of patients with advanced non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations and resistance to targeted therapy.

Patients with advanced NSCLC and EGFR mutations were assigned to control group and treatment group. The control group received 500 mg·m^-2 pemetrexed disodium for injection by intravenous infusion on the first day + 7.5 mg·kg^-1 bevacizumab injection by intravenous infusion every 3 weeks + 80 mg·m^-2 nedaplatin by intravenous infusion on the first day. On the basis of control group, the treatment group received 200 mg tislelizumab injection by intravenous infusion every 3 weeks. Two groups were treated for 3 cycles with 3 weeks per cycle. The clinical efficacy, tumor markers, quality of life and safety were compared between two groups.

Treatment group was enrolled 51 cases; control group was enrolled 51 cases. After treatment, the overall effective rates of treatment and control groups were 54.90% (28 cases / 51 cases) and 21.57% (11 cases / 51 cases), with statistically significant difference (P<0.01). After treatment, the levels of carcinoembryonic antigen (CEA) in treatment and control groups were (6.67±1.24) and (11.58±1.36) ng·mL^-1; the levels of cytokeratin-19 fragments were (7.64±1.47) and (12.25±1.63) ng·mL^-1; the levels of neuron-specific enolase were (22.65±2.81) and (25.05±2.94) ng·mL^-1; the quality of life scores were (73.67±6.24) and (64.45±5.36) points; the median progression-free survival were 7.00 and 10.00 months; the median overall survival were 14.00 and 20.00 months, respectively. The differences of above indexes were statistically significant between two groups (all P<0.05). The adverse drug reactions of two groups were nausea and vomiting, liver function impairment and renal function impairment. The incidences of total adverse drug reactions in treatment and control groups were 27.45% (14 cases/51 cases) and 31.37% (16 cases/51 cases), without statistically significant difference (P>0.05).

Tislelizumab injection has a definitive clinical efficacy in the treatment of patients with advanced NSCLC harboring EGFR mutations and resistance to targeted therapy, which can reduce the tumor marker levels, improve the quality of life, with high safety.