Background: Since 2019, six PD-1/PD-L1 inhibitors (sugemalimab, sintilimab, pembrolizumab, camrelizumab, atezolizumab and tislelizumab ) are already in or about to be launched in the Chinese market, but there are no head-to-head RCT studies reporting the comparative efficacy nor the long-term effectiveness. Therefore, this study aims to indirectly compare these six drugs and project to the final outcome in order to provide evidence for clinical decision and Chinese national reimbursement drug listing.

Methods: We collected phase III clinical trials targeted on stage IIIB–IV patients for first-line immunotherapy of sq-NSCLC by systematically searching databases and conference abstracts. Chemotherapies were limited to paclitaxel/gemcitabine plus platinum. KEYNOTE-407 (pembrolizumab plus chemotherapy versus chemotherapy) was chosen as the anchor for indirect comparison. We used non-proportional hazard ratio to adjust for PFS rate cycle by cycle among drug groups, and proportional hazard ratio to adjust for OS rate. Life-year estimates in PFS and OS were calculated from Kaplan-Meier survival curve and extrapolated survival curve based on partitional survival model. We also performed sensitivity analysis using the range of parameters distribution as well as different comparison methods to test the robustness of the results.

Results: A total of 6 clinical trials were included. When followed up till 24 months, sugemalimab achieved the highest PFS benefit (1.061 LYs), with camrelizumab (1.03 LYs), sintilimab (0.9264 LYs), pembrolizumab (0.9255 LYs), tislelizumab (0.788 LYs) and atezolizumab (0.734 LYs) ranking in order. When extrapolated to 120 months, sugemalimab achieved the highest OS benefit (3.799 LYs), with camrelizumab (3.379 LYs), sintilimab (3.287 LYs), pembrolizumab (2.644 LYs) and atezolizumab (2.107 LYs) ranking in order. When simply comparing HR, sugemalimab ranked first in PFS (38%) and OS (42%). The results were robust under all conditions.

Conclusions: Sugemalimab is significantly superior both in PFS and OS benefits for advanced sq-NSCLC patients.