1.第一部分 LAF-bTMB作为晚期NSCLC一线免疫联合化疗疗效预测指标的探索

【背景】免疫检查点抑制（immune checkpoint inhibitors, ICI）联合化疗的模式作为晚期非小细胞肺癌（non-small cell lung cancer, NSCLC）的一线治疗标准尚未发现有确切的疗效预测生物标志物（biomarker）。既往研究已经证实低频血液肿瘤突变负荷(low allele frequency adjusted blood-based tumor mutational burden, LAF-bTMB)与ICI单药治疗疗效相关，但关于LAF-bTMB与ICI联合化疗模式的疗效相关性数据目前尚未有文献报道。本研究旨在探索LAF-bTMB能否作为晚期NSCLC一线免疫联合化疗疗效的生物标志物（biomarker）。

【方法】本研究入选自2020年5月至2021年12月在中国医学科学院肿瘤医院初诊即为晚期NSCLC的患者，全部患者接受一线ICI联合化疗治疗，采集患者的临床信息、治疗信息及治疗前的外周血液样本10ml，每2个周期对患者进行疗效评价，随访患者的无进展生存期（progression-free survival，PFS），对患者的血样进行NGS检测，计算LAF-bTMB，探索LAF-bTMB与疗效的关系。

【结果】共42例NSCLC患者纳入本研究，19例患者获得部分缓解（partial response, PR），客观缓解率（objective response rate, ORR）为45%。全部患者的中位PFS为13.4个月。治疗有效组（responder, R）的中位PFS和中位OS均优于治疗无效组（non-responder, NR）（中位PFS：16.4个月vs.7.2个月，p=0.028；中位OS：NE vs.9.3个月，p=0.016）；R组的bTMB、LAF-bTMB与NR组无统计学差异;当LAF-bTMB cut-off值为8muts/Mb时，LAF-bTMB≤8muts/Mb的患者ORR显著高于LAF-bTMB＞8muts/Mb的患者（ORR分别为61%和26%，p=0.033），尚未发现LAF-bTMB与PFS和OS具有相关性。

【结论】LAF-bTMB作为晚期NSCLC一线免疫联合化疗的预测指标有一定的局限性，后续还需探索更为合适的biomarker用来筛选免疫联合化疗的优势患者群体。

2.第二部分 PD-L1表达指导下免疫检查点抑制剂治疗晚期非小细胞肺癌的真实世界研究

【背景】免疫检查点抑制剂（immune checkpoint inhibitor, ICI）已经是晚期非小细胞肺癌（non-small cell lung cancer, NSCLC）标准治疗方案之一，诸多临床试验发现PD-L1作为免疫治疗的生物标志物可以预测ICI治疗的疗效，但国内真实世界中PD-L1对ICI疗效的预测作用还没有大规模数据的报告，本研究旨在探索真实世界中PD-L1在中国晚期NSCLC患者免疫治疗中的疗效预测作用。

【方法】本研究为多中心研究，收集了从2018年1月至2021年12月在中国医学科学院肿瘤医院、北京协和医院、北京大学第三医院、首都医科大学附属胸科医院就诊的接受过ICI治疗的晚期NSCLC患者的临床资料，并随访患者的生存数据。统计各线治疗前PD-L1表达检测情况、对PD-L1表达水平与临床疗效、生存数据之间的关系进行统计学分析。

【结果】共有551例符合条件的晚期NSCLC患者纳入本研究，根据患者使用ICI的时间分与治疗模式不同分为三个组。（1）第一组纳入一线接受ICI治疗并且PD-L1≥50%的患者，共有67人，ICI单药与ICI联合化疗之间的客观缓解率（objective response rate, ORR）和无进展生存（progression-free survival, PFS）未见到差异（ORR:41.2% vs. 50%，p=0.529;PFS 7.6 vs.12.5个月,HR 0.300，95%CI 0.313-1.431，p=0.142）。使用ICI单药相比于ICI联合化疗的患者3个月内更容易出现疾病进展（p=0.021）。（2）第二组全部纳入一线接受含ICI治疗的患者，共279例，67%的患者接受了PD-L1检测，接受免疫联合化疗的患者中有64%在治疗前进行了PD-L1检测。PD-L1≥50%的患者接受一线ICI治疗的ORR比PD-L1<1%的患者显著提高（47.8% vs.26.4%，p=0.017），PD-L1≥50%的患者相比PD-L1 1-49%患者的PFS显著延长（HR 0.619，95%CI 0.384-0.998，p=0.049），但在OS方面，PD-L1≥50%的患者劣于PD-L1 1-49%的患者（HR 2.821，95%CI 1.041-7.65，p=0.042）。（3）第三组纳入二线及后线接受ICI治疗的患者，共272例，46%的患者在使用免疫治疗前接受了PD-L1的检测。PD-L1≥50%的患者ORR显著高于PD-L1≤49%的患者，PD-L1≥50%、PD-L1 1-49%和PD-1阴性的患者在PFS（log-rank p=0.1105）和OS（log-rank p=0.2647）方面未见到差异。

【结论】对于中国晚期NSCLC患者，一线使用ICI单药与ICI联合化疗都可以改善PD-L1≥50%患者的PFS和OS,但需要警惕ICI单药带来的快速进展风险。PD-L1可以预测晚期NSCLC一线免疫治疗的疗效，因此在一线治疗前检测PD-L1十分有必要；在二线及后线治疗中，PD-L1的检测可以作为ICI用药前的补充诊断。

3.第三部分 特瑞普利单抗联合安罗替尼在EGFR突变耐药的晚期非鳞非小细胞肺癌中疗效及安全性探索

【背景】EGFR-TKI耐药后的治疗一直是临床实践中面临的挑战和研究的热点。免疫检查点抑制剂（immune checkpoint inhibitor, ICI）联合抗血管生成治疗药物在基础研究中发现可以协同增效，但ICI联合抗血管生成治疗模式在此类耐药患者中的效果还未知。本研究为前瞻性单臂II期研究，试图探索特瑞普利单抗联合安罗替尼在EGFR晚期突变耐药的非小细胞肺癌患者中的疗效和安全性。

【方法】本研究纳入自2020年5月至2021年10月在中国医学科学院肿瘤医院就诊的EGFR敏感突变的晚期肺腺癌患者，一线治疗接受一代或二代EGFR-TKI后耐药，组织或血液检查提示T790M突变阴性患者，或为一线或二线治疗使用三代EGFR-TKI后进展的患者。入组后给与静脉注射特瑞普利单抗（240mg/第1天）联合口服安罗替尼（12mg/日，第1至14天），21天为1个周期，每2周期后评估疗效直至疾病进展。若患者无法耐受此方案或疾病进展则出组。主要终点为客观缓解率（objective response rate，ORR），次要终点为无进展生存（progression-free survival, PFS）。基线血及进展后的血样经NGS检测基因突变频率、计算bTMB，MSD法测定血液可溶性PD-L1表达水平用以探索疗效预测指标。

【结果】共19例患者入组，患者初诊均携带常见EGFR突变，12例为EGFR 19DEL，6例为EGFR 21 L858R突变，1例为T790M突变。11例患者（57.9%）最佳疗效评价为疾病稳定（stable disease, SD），8例患者最佳疗效评价为疾病进展（progressive disease, PD）。患者的ORR为0%，疾病控制率（disease control rate，DCR）为57.9%，患者中位PFS为2.1个月（95%CI 0.251-3.949）。III级及以上不良反应发生率为11%，常见不良反应包括甲状腺功能减退（12/19）、乏力（9/19）、高血压（8/19）、转氨酶升高（8/19）、蛋白尿（4/19）等，未发现既往研究未报道的不良反应。探索性分析发现SD组患者的入组治疗前血EGFR突变丰度（allele frequency, AF）低于PD组（p=0.147）。当EGFR AF cutoff值为2时，EGFR AF低组的PFS有长于EGFR AF高组的趋势（p=0.059）。可溶性PD-L1高水平患者的PFS也有延长的趋势，但不显著（p=0.16）。

【结论】特瑞普利单抗联合安罗替尼在EGFR-TKI耐药的晚期NSCLC且既往未接受化疗的患者中耐受性尚可,但未达到预期的疗效。低EGFR突变丰度、高sPD-L1的患者可能是潜在的获益类型，但仍需进一步探索与验证。

1.An exploratory study of LAF-bTMB as predictor for patients with NSCLC treated with PD-1 inhibitor plus chemotherapy

Background: Immune checkpoint inhibitor (ICI) combined with chemotherapy is one of the standards of care for advanced Non-small cell lung cancer (NSCLC) without driver mutations. However, the biomarker of combination therapy is still unknown. Although previous studies have confirmed that low allele frequency adjusted blood-based tumor mutational burden (LAF-bTMB) is associated with the efficacy of ICI monotherapy, there has been no report on the correlation between the efficacy of LAF-bTMB and ICI combined chemotherapy. This study aimed to explore whether LAF-bTMB can be used as a biomarker for the efficacy of immunotherapy combined with chemotherapy in advanced NSCLC.

Methods: This study enrolled patients diagnosed with advanced NSCLC and who received ICI combined with chemotherapy for first-line therapy from May 2020 to December 2021 at Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. Clinical information, treatment information, survival data, and peripheral blood samples of every patient before treatment were collected. Next-generation sequencing was performed on plasma samples collected before treatment to evaluate bTMB and LAF-bTMB.

Results: A total of 42 patients with NSCLC were included in the study. In this cohort, 19 patients achieved partial response (PR), and the objective response rate (ORR) was 45%. The median progression-free survival (PFS) of all patients was 13.4 months. Both PFS and the overall survival (OS) were significantly longer in the responder (R) group than in the non-responder (NR) group (mPFS:16.4months vs.7.2months, p=0.028; mOS: NEvs.9.3months, p=0.016). There was no significant difference in bTMB and LAF-BTMB between the R group and the NR group. The ORR of patients with LAF-bTMB≤8muts/Mb was significantly higher than that of patients with LAF-BTMB>8muts/Mb(ORR 61% vs. 26%, respectively, p=0.033).No correlation has been found between LAF-bTMB and PFS or OS.

Conclusions: LAF-bTMB has some limitations as a predictor of first-line immunochemotherapy for advanced NSCLC. More suitable biomarkers need to be explored to screen patients with better efficacy of immunotherapy combined with chemotherapy in the future

2.Predictor value of PD-L1 for immune checkpoint inhibitor in advanced non-small cell lung cancer: A real-world study

Background: Immune checkpoint inhibitor monotherapy or in combination with chemotherapy is now one of the standards of care in the first line for advanced non-small cell lung cancer (NSCLC) without driver mutations. PD-L1expression has been shown to be associated with the efficacy of ICI in serval clinical trials. However, there is no large-scale research reported on the predictive effect of PD-L1 on ICI efficacy in the real world in China. This study aimed to explore the predictive effect of PD-L1 in immunotherapy for advanced NSCLC patients in the real world.

Methods: This is a multi-center retrospective study. Clinical data of advanced NSCLC patients who received ICI therapy were collected between January 2018 and December 2021 in National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Peking Union Medical College Hospital, Peking University Third Hospital, Beijing Chest Hospital. Survival data of patients were followed up until March 2022.The detection percentage of PD-L1 expression, the relationship of PD-L1 expression level with clinical efficacy and survival were analyzed.

Results: A total of 551 patients with advanced NSCLC were enrolled in this study and divided into three groups according to the different treatment line and regimens. (1) 67 patients with PD-L1≥50% used ICI as their first-line therapy. The objective response rate (ORR) and progression-free survival (PFS) did not differentiate significantly between patients treated with ICI monotherapy and ICI combined chemotherapy (ORR:41.2% vs. 50%, p=0.529；PFS 7.6 vs.12.5 months, HR 0.300, 95%CI 0.313-1.431, p=0.142).Patients treated with ICI alone were more likely to have disease progression within 3 months than those treated with ICI plus chemotherapy (p=0.021).(2) 279 patients were treated with ICI monotherapy or ICI-based therapy in first-line.67% of 279 patients underwent PD-L1 testing before treatment.64% patient treated with immunochemotherapy detected PD-L1 expression in the baseline. The ORR of patients with PD-L1≥50% receiving first-line immunotherapy was significantly higher than that of patients with PD-L1<1% (47.8% vs.26.4%, p=0.017).PFS of patients with PD-L1≥50% was significantly longer than that of patients with PD-L1 1-49% (HR 0.619, 95%CI 0.384-0.998, p=0.049).The overall survival (OS) of patients with PD-L1≥50% was worse than that of patients with PD-L1 1-49%(HR 2.821,95%CI 1.041-7.65,p=0.042).(3)272 patients received ICI in the second and posterior line.46% of them received PD-L1 test before immunotherapy. ORR of patients with PD-L1≥50% was significantly higher than that of patients with PD-L1≤49%.There were no significant difference observed in both PFS (log-rank p=0.1105) and OS (log-rank p=0.2647) of patients with PD-L1≥50%, PD-L1 1-49% and PD-1 <1%.

Conclusions: ICI monotherapy and ICI combined chemotherapy can improve PFS and OS in advanced NSCLC patients with PD-L1≥50%, but the risk of rapid progression caused by ICI alone should be warned. PD-L1 high expression was associated with better response to first-line immunotherapy. In second-line and posterior line treatment, PD-L1 detection can be used as a supplementary diagnosis before immunotherapy.

3.Efficacy and safety of toripalimab combined with anlotinib in patients with advanced non-small cell lung cancer after failure of EGFR-TKI treatment.

Background: Patients treated with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) will inevitably face the problem of drug resistance. To date, multiple clinical studies have reported promising results using immune checkpoint inhibitors (ICIs) or antiangiogenic therapy for EGFR-TKI resistance. But the combination therapy of immunotherapy plus antiangiogenic drugs is still controversial. In this study, we propose to evaluate the efficacy and safety of toripalimab combined with anlotinib in patients with advanced non-small cell lung cancer (NSCLC) after the failure of EGFR-TKI treatment.

Methods: Previously the EGFR-TKI treated patients with advanced NSCLC were enrolled in this study. Patients were given intravenous toripalimab (240mg, day 1) combined with oral anlotinib (12mg, once daily, day 1-day 14) for each therapy cycle of 21 days. Efficacy assessment was performed after 2 cycles of treatment. Patients without progressive disease after 4 cycles received the original regimen for maintenance treatment until disease progression or unacceptable adverse events. The primary endpoint is objective response rate (ORR) and the secondary endpoint is progression-free survival (PFS). The frequency of gene mutation was detected by NGS and TMB was calculated. The expression level of soluble PD-L1 was determined by ELISA.

Results: A total of 19 patients with EGFR mutation were enrolled，including 12 cases of 19 DEL, 6 cases of EGFR 21 L858R mutation and 1 patient with T790M mutation .The median treatment cycle was 2 (range 2-14 cycles). The best response was stable disease (SD) which was observed in 11 patients (57.9%) and progressive disease (PD) in 8 patients. The ORR was 0%, and the median PFS was 2.1 months (95%CI 0.251-3.949). The PFS of patients with SD was approximately 2 months longer than that of patients with PD (mPFS 3.5 vs.1.4 months, HR 0.104,95%CI0.0021-0.521). The incidence of grade III or higher adverse events (AEs) was 11%. The most common AEs was hypothyroidism (12/19), and no new adverse events were found that had not been reported in previous studies. Exploratory analysis showed that EGFR allele frequence (AF) at baseline in the SD group was lower than in the PD group(p=0.147). When the cut-off value of EGFR AF was 2%, patients with low EGFR AF had a PFS benefit trend, but there was no statistical significance (log-rank p =0.059).

Conclusions: Ttoripalimab combined with anlotinib did not show antitumor activity in EGFR-TKI resistant patients. EGFR mutation AF，sPD-L1 may be related to the efficacy of immunotherapy after EGFR-TKI resistance, which needs to be further explored in subsequent trials.