Real-world data on efficacy and safety of pembrolizumab in the first-line treatment of metastatic lung cancer in patients with PD-L1 expression >0% - a single center experience

OBJECTIVE: With the advent of immunotherapy, there has been a significant improvement in the outcomes of non-small cell lung cancer treatment. Several clinical trials have con-firmed the efficacy and safety of pembrolizumab, but research with real-world data is needed to confirm the findings from clinical trials.PATIENTS AND METHODS: In this retrospective study, data on the treatment of lung cancer with pembrolizumab were analyzed in 78 patients who started pembrolizumab therapy as first-line treatment for metastatic disease at University Hospital Centre Osijek, from May 15, 2018, until December 31, 2021. November 30, 2022, was set as the last date of data monitoring. Patients who had received less than 3 cycles of pembrolizumab were excluded from the study. The main objectives of the study were OS (overall survival) and PFS (progression-free survival). The differences in the incidence and type of adverse events between the two groups of patients were also compared.RESULTS: Kaplan-Meier analysis of the survival determined that the median OS was 20 months and PFS was 13 months. Although OS and PFS are longer in patients with PD-L1 (programmed death-ligand 1) >= 50%, the differences are not statistically significant. The most commonly reported adverse events related to pembrolizumab treatment were gastrointestinal ad-verse events. No significant differences were found in the frequency of occurrence of certain adverse events between the two groups of patients.CONCLUSIONS: This study demonstrates that real-world data for pembrolizumab treatment of non-small cell lung cancer confirm the efficacy and safety indicated by clinical trials. Nevertheless, it is necessary to assess the patient's general condition more objectively before starting the treatment.