Efficiency and toxicity of nab-paclitaxel and camrelizumab in the second or above line treatment of advanced non-small cell lung cancer: a retrospective cohort study

BACKGROUND: Paclitaxel-based chemotherapy represented by nanoparticle albumin-bound paclitaxel (nab-ptx) combined with programmed cell death protein 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors has become the standard model for the 1(st) treatment of advanced non-small cell lung cancer (NSCLC) with negative driver genes (such as EGFR, ALK, etc.), indicating that nab-ptx and PD-1/PD-L1 inhibitors are synergistic. Considering PD-1/PD-L1 inhibitors alone or chemotherapy single has limited efficiency in the 2(nd) line or above of NSCLC, so it is of great significance to explore the combination of PD-1/PD-L1 inhibitors and nab-ptx to further improve the therapeutic efficiency in such field. METHODS: We retrospectively collected the date of these advanced NSCLC patients who accept the combination treatment of PD-1/PD-L1 inhibitor and nab-ptx in the 2(nd) or above line. We further analysed baseline clinical characteristics, therapeutic efficacy, treatment-related adverse events (AEs) and followed up survival. The main parameters of the study were objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS) and AEs. RESULTS: A total of 53 patients were enrolled in this study. The preliminary results indicated that the ORR of the combination of camrelizumab and nab-ptx was about 36% in the 2(nd) or above line of NSCLC, with 19 cases of partial response (PR), 16 of stable disease (SD), and 18 cases of progressive disease (PD); the mean PFS and OS were 5 months and 10 months, respectively. Further subgroup analysis demonstrated that the expression of PD-L1 level and the decrease of regulatory T cell (Treg) correlated with the efficiency. the main adverse reactions were neuropathy, bone marrow suppression, fatigue, and hypothyroidism, most of which were mild and tolerable, indicating such regimen was higher efficiency and lower cytotoxicity for NSCLC. CONCLUSIONS: The combination of nab-ptx and camrelizumab shows promising efficiency and lower toxicities for advanced NSCLC in the 2nd or above line treatment. The mechanism of action may be related to depleting Treg ratio; such a regimen may have the potential to become an effective treatment approach for NSCLC. However, due to the limitation of sample size, the real value of this regimen needs to be further confirmed in the future.