Background: Lung cancer is the first killer among all types of cancer worldwide. Immune checkpoint inhibitors (ICIs) have revolutionized the oncology practice in the field of advanced lung cancer. ICIs have significantly improved the median overall survival rates (mOS) in advanced lung cancer patients and improved their quality of life. In April 2023 ICIs have been publicly funded in New Zealand (NZ) for advanced lung cancer, which makes NZ one of the last developed countries where the public have got access to ICIs. This systematic review (SR) has been conducted to examine the most up-to-date data for using ICIs as a subsequent line in advanced NSCLC, develop recommendations for using ICIs in this arena and support the decision to publicly fund ICIs in NZ.
Methods: SR has been conducted and the Cochrane SR methods have been adopted. Multicentre randomized controlled trials (RCTs) in adults with advanced NSCLC which used ICIs as a subsequent line of treatment have been included. The included RCTs should be published in the English language.
Results and Conclusion: 2153 studies were identified. 2141 were excluded and 12 published papers were included. There were 7 RCTs and 5 follow-up data on the original trials. 3974 patients were recruited in the included RCTs. Extended follow-up ranged from 2 to 5 years. In the included RCTs Pembrolizumab, Nivolumab, Atezolizumab or Avelumab were compared head-to-head against Docetaxel as a subsequent line of treatment in advanced NSCLC. The included RCTs have all shown low risk of bias. The SR has shown the efficacy of targeting the PD1 – PD-L1 pathway. Avelumab did not improve mOS. ICIs as a subsequent line in advanced NSCLC did not improve the median PFS rate but improved the mOS and showed endured response over several years regardless of the PDL-1 expression level. EGFR mutant NSCLC did not show a response to ICIs. Allowing patients who received Paclitaxel as a first line to receive Docetaxel as a second line did not affect the mOS or the outcome of the trials. It is highly recommended that Immune-Modified Response Evaluation Criteria In Solid Tumors (imRECIST) criteria be used in future clinical trials examining the effect of ICIs. ICIs are highly recommended to be publicly funded in NZ for advanced NSCLC.