Impact of prior immunotherapy on Paclitaxel/Bevacizumab in advanced non-squamous cell lung cancer

Charlotte Domblides^1,2*Agathe Peyret^1,2Clémentine Le Berrurier^1,2Luc Héraudet^1,2Tara Delon^1,2Maéva C Zysman^1,2Mathieu Larroquette^1,2Laura Leroy³Sophie Cousin³

• ¹Bordeaux University Hospital - Hôpital Saint-André, Bordeaux, France
• ²Universite de Bordeaux, Talence, France
• ³Institut Bergonie, Bordeaux, France

Even if immunotherapy is becoming essential in the management of advanced non-small cell lung cancer (NSCLC), the best treatment sequence remains to be determined. Some data showed that immunotherapy prior to chemotherapy with Paclitaxel Bevacizumab (PB) appeared to be an interesting option. Here, we propose to study this sequence in a validation cohort from the Bordeaux Cancer Institute (France). We retrospectively included all patients with NSCLC diagnosed between 2015 and 2021, treated with PB directly after immunotherapy (CAI) or without prior exposure to immunotherapy (CWPI). The primary outcome was the time to treatment discontinuation (TTD), and secondary endpoints were progressionfree survival (PFS), overall survival (OS), overall response rate (ORR), and disease control rate (DCR). We included 121 patients, 60 in the CAI and 61 in the CWPI groups. Characteristics were comparable, even for the main prognosis criteria. Median number of lines received was higher in CAI (4 vs 2). There was a significant difference in TTD (HR = 0.55, 95% CI 0.34-0.72; p = 0.0002), PFS (HR = 0.60, 95% CI 0.41-0.87, p < 0.005) and ORR (58% versus 38%, p < 0.05) between the two groups, as well as a non-statistically significant trend towards better OS (7.40 vs 3.70 months, HR = 0.76, 95% CI 0.52-1.10, p = 0.15). We found a significant difference in TTD, PFS and ORR for PB after exposure to immunotherapy, with a trend toward better OS. This suggests that sequential treatment with immunotherapy followed by chemotherapy could be an interesting option after first-line treatment.