WCLC 2025 - Posters & ePosters-EP.18.05 Tislelizumab Combined With Low-Dose Chemotherapy in Previously Treated Advanced Squamous NSCLC

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This phase II prospective, single-arm study investigated the safety and efficacy of low-dose chemotherapy combined with the anti-PD-1 antibody tislelizumab as a second-line treatment in patients with previously treated advanced squamous non-small cell lung cancer (SQ-NSCLC). Thirteen patients with histologically confirmed locally advanced or metastatic SQ-NSCLC who had progressed after first-line systemic therapy were enrolled between August 2022 and June 2024. Treatment included low-dose nedaplatin or gemcitabine plus tislelizumab every three weeks for six cycles, followed by maintenance tislelizumab for up to two years or until disease progression.<br /><br />Among 11 evaluable patients, the primary endpoint of 6-month progression-free survival (PFS) rate was 63.6%, exceeding expectations compared with historical median PFS of approximately 3 months for standard second-line single-agent chemotherapy or immunotherapy. The objective response rate (ORR) was 36.4% (4 partial responses), disease control rate (DCR) was 72.7%, median PFS was 9.0 months, and 1-year overall survival (OS) rate was 72.7%. Median OS was not reached at a median follow-up of 27 months. Treatment was generally well tolerated, though two patients experienced grade 3-4 hematologic toxicities including thrombocytopenia and leukopenia.<br /><br />The study highlights that combining low-dose chemotherapy with immunotherapy may enhance anti-tumor immune responses while minimizing immunosuppression seen with conventional maximum tolerated dose chemotherapy. Preclinical evidence suggests low-dose chemotherapy can upregulate PD-L1 expression and stimulate immune memory, synergizing with checkpoint blockade. These findings support further exploration of this chemoimmunotherapy strategy as an effective and safe second-line option for advanced SQ-NSCLC, potentially improving outcomes beyond current standards. Larger, controlled trials are warranted to confirm these promising results.

Asset Subtitle

Binxun Ling

Meta Tag

Speaker Binxun Ling

Topic Clinical Trials in Progress

Keywords

Phase II study

low-dose chemotherapy

tislelizumab

anti-PD-1 antibody

second-line treatment

squamous non-small cell lung cancer

progression-free survival

objective response rate

disease control rate

immunotherapy