Effect of first-line bevacizumab on prognosis of second or later-line immunotherapy in patients with advanced non-squamous non-small cell lung cancer: A retrospective analysis.

e20570 Background: Previous studies have demonstrated that anti-angiogenic agents have the capacity to regulate tumor microenvironment and may affect the clinical effect of immune checkpoint inhibitors (ICIs). However, the impact of previous anti-angiogenic agents on clinical outcomes of non-squamous non-small cell lung cancer (nsqNSCLC) patients treated with ICIs remains unclear. Methods: In the present study, we incorporated POPLAR, OAK, and BIRCH trials with a total of 912 non-squamous NSCLC patients. Using Vivli data-sharing platform, we have obtained specific clinical information about individual patients. The progression-free survival (PFS) and overall survival (OS) were analyzed by Kaplan-Meier analysis with a log-rank test, and the corresponding hazard ratio (HR) and 95% confidence interval (CI) were estimated using the Cox proportional regression model. Chi-squared test was used to compare proportions between different groups. All statistical analysis and plotting were done in R version 4.1.1 and SPSS R26.0.0.2. P less than 0.05 was considered statistically significant. Results: In the overall cohort, PFS (2.77 months vs. 2.83 months; hazard ratio [HR],1.1; 95% confidence interval [CI], 0.9 to 1.3; p = 0.43) and OS (15.1 months vs. 14.3 months; HR,1.0; 95% CI, 0.8 to 1.3; p = 0.86) in patients treated with bevacizumab before atezolizumab (pre-bevacizumab group) and patients treated without bevacizumab before atezolizumab (no pre-bevacizumab group) were not statistically different. Merely in patients with KRAS mutation, no pre-bevacizumab group had an improved PFS (4.04 months vs. 1.64 months; HR,1.7; 95% CI, 1.0 to 2.7; p = 0.04) as compared to the pre-bevacizumab group. Longer use of bevacizumab (≥1.43 months) before atezolizumab suggested a longer PFS compared with shorter use of bevacizumab ( < 1.43 months) (20.07 months vs. 2.75 months; HR,0.40; 95% CI, 0.17 to 0.95; p = 0.03). Conclusions: In conclusion, our study demonstrated that whether or not first-line bevacizumab is given has no effect on PFS or OS of second-line or later-line immunotherapies. Patients with longer duration of first-line bevacizumab use have a longer PFS on later immunotherapy. The more appropriate timing and sequence of administration of anti-angiogenic agents and ICIs will help us achieve a better therapeutic effect in the clinical practice of patients with advanced NSCLC.