A French Multicenter Real-Life Study on the Biological and Clinical Parameters Associated With Response to Immune Checkpoint Inhibitors (ICIs) in Second-Line Treatment of Advanced Urothelial Carcinoma: Impact of Antibiotics Administration at the Time of ICIs Initiation

In this study, we investigated the effect of clinical and biological criteria on response to immunotherapy in advanced urothelial cancer. We found that patients who received antibiotics had a lower probability of achieving a response to immunotherapy, while those with locally advanced or lymph node-only disease appeared to have better chance of response to immunotherapy than those with bone or visceral involvement. Background: After failure of first-line chemotherapy, standard of care for advanced urothelial cancer (aUC) is immune checkpoint inhibitors (ICIs) targeting PD-1/PD-L1 pathway. Several prognostic models (Bajorin and Bellmunt scores) have been evaluated, but only in the context of chemotherapy. Objective: To study whether the variables in these scores and new emerging clinical and biological criteria have an impact on the probability of objective response in aUC treated with ICIs in 2nd-line setting and beyond. Materials and methods: Between October 2016 and March 2023, we included 168 patients treated with ICIs in 2nd-line setting or more in 2 French centers. Variables of interest were selected after a literature review and collected retrospectively. Analyses used log-rank test and multivariate models (binary logistic and Cox regressions). Results and limitations: Median age at diagnosis was 68 years. Patients presented with bladder tumors in 73.8% and upper urinary tract tumors in 26.2%. 63.7% of patients had received only one line of chemotherapy before ICIs. Median follow-up after starting ICIs was 8.9 months. The variables statistically associated with objective response were: - The presence of locally advanced or lymph node-only disease compared with visceral involvement (adjusted Odds Ratio 0.19, 95% confidence interval [0.06-0.55], P = .002) and bone-only involvement (aOR 0.22 [0.080.64], P = .005) - The absence of antibiotic therapy the month before/after ICIs initiation (aOR 0.31 [0.12-0.84], P = .021). Limitations included retrospective design and small number of patients included. Conclusion: This real-life study from 2 French centers found a higher likelihood of objective response: - In the absence of antibiotic therapy at ICIs initiation: - In locally advanced or lymph node-only disease, in contrast to visceral or bone-only disease. Our results suggest that negative impact of antibiotic therapy on the response to ICIs needs to be further investigated to optimize the management of these patients.