Chemotherapy combined with immunotherapy has become the first-line standard treatment regimen for metastatic non-small cell lung cancer (NSCLC). QL1706 is an antibody that can simultaneously block the CTLA-4 and PD-1. In a phase II clinical study, when QL1706 was combined with chemotherapy for first-line treatment of metastatic NSCLC, the median progression-free survival (mPFS) was 6.8 months and the objective response rate (ORR) was 45% at a median follow-up time of 12.6 months (range, 0.4-15.2 months).
Radiotherapy is one of the commonly used local treatment modalities for tumors, which has a synergistic effect with immunotherapy, can enhance the response to immunotherapy, and trigger the abscopal effect. Quad shot radiotherapy is a periodic pulsed hypofractionated radiotherapy, with a specific mode as follows: 2 fractions per day, with an interval of more than 6 hours between the two fractions, for 2 consecutive days, with a total dose of 14-14.8 Gy. This regimen can be repeated every 3-4 weeks for a total of 3 cycles, with a total treatment dose of approximately 44-48 Gy, and it can be used for palliative treatment of various advanced tumors.
This project intends to explore whether the addition of Quad shot radiotherapy to QL1706 combined with chemotherapy can improve local and systemic tumor control rates, prolong patients' PFS, and evaluate the safety of the combined therapy in treatment-naive patients with metastatic NSCLC.