Sintilimab Combined with Nanoparticle Albumin-Bound Paclitaxel-Based Chemotherapy in Severe Locally Advanced or Metastatic Squamous NSCLC Showed Good Efficacy and Safety: A Pilot Retrospective Analysis

Introduction: Squamous non-small cell lung carcinoma (sqNSCLC) is associated with a poorer prognosis and limited treatment options. Sintilizumab combined with chemotherapy is used as first-line treatment for advanced sqNSCLC. However, the efficacy and safety of sintilimab combined with nanoparticle albumin-bound paclitaxel-based chemotherapy for severe squamous NSCLC remain to be unknown in clinical studies. Methods: Patients with confirmed unresectable stage III/IV sqNSCLC were retrospectively collected between July 1 st , 2019, and December 31 st . According to performance status (PS) scores, these patients received first-line sintilimab plus nab-PTX-based chemotherapy were divided into severe (PS=2) and non-severe groups (PS=0– 1). The treatment regimen was repeated every 3 weeks for a maximum of six cycles, or until unacceptable toxicity occurred. The primary endpoint of this study was to assess progression free survival (PFS), with secondary endpoints including the objective response rate (ORR), adverse events (AEs) and disease control rate (DCR). Results: Among 367 patients with unresectable stage III/IV sqNSCLC, 28 male patients, with a median age of 65.5 years, received first-line sintilimab plus nab-PTX-based chemotherapy. These patients were divided into a severe group (11 patients) and a non-severe group (17 patients). The severe group had a significantly higher incidence of chronic obstructive pulmonary disease (COPD) compared to the non-severe group (54.5% vs 11.8%, p = 0.03). The two groups had a similar median number of treatment cycles and safety profiles. Although the severe group showed higher ORR (63.6% vs 47.1%) and DCR (100% vs 76.5%) than the non-severe group, these differences were not statistically significant. Median PFS and Kaplan-Meier curves were also comparable between the groups. Conclusion: Sintilimab combined with nab-PTX-based chemotherapy was effective and well tolerated in a small sample of severe lung squamous cell carcinoma population. This combination may offer a potential treatment option for these patients. Keywords: chemotherapy, immunotherapy, severe lung cancer, squamous non-small cell lung carcinoma