Programmed cell death protein-1/ligand-1 (PD-1/L1)阻断已经成为非小细胞肺癌(NSCLC)患者治疗的突破，但仍缺乏有效的筛选患者的方法。在这里我们报告了一种新型的68Ga标记的纳米抗体[68Ga]Ga-THP-APN09用于小鼠模型中PD-L1状态的PET成像以及NSCLC患者的首次临床前研究。[68Ga]Ga-THP-APN09通过位点特异性放射性标记制备，无需进一步纯化。在人类肺腺癌细胞系A549、NSCLC细胞系H1975和人类PD-L1基因转染A549细胞(A549PD-L1)中完成了细胞摄取实验。通过这三种肿瘤细胞类型的肿瘤负荷小鼠进行了PD-L1状态的成像和生物分布的研究。该首个临床前临床转化试验已登记为NCT05156515。安全性、放射剂量学、生物分布以及示踪物摄取与免疫组织化学染色和主要病理反应(MPR)的相关性在接受辅助免疫治疗联合化疗的NSCLC患者中进行了评估。 在10分钟内，[68Ga]Ga-THP-APN09在室温和6.0-6.5的pH下实现了放射性合成，具有较高的放射化学产率(>99%)和13.9-27.8 GBq/μmol的摩尔活性。细胞摄取研究的结果反映了流式细胞术观察到的表面PD-L1表达水平的差异，顺序为A549PD-L1 > H1975 > A549。在小动物PET/CT成像中，H1975和A549PD-L1肿瘤可以清晰显示，与PD-L1阴性的A549肿瘤相比显示了8.3:1和2.2:1的比率。体外生物分布研究显示，肿瘤摄取与PET结果一致，最高的A549PD-L1摄取最多(8.20 ± 0.87%ID/g)，其次是H1975(3.69 ± 0.50%ID/g)和A549(0.90 ± 0.16%ID/g)。共有9名可切除的NSCLC患者参加了临床研究。[68Ga]Ga-THP-APN09的摄取主要观察到在肾脏和脾脏中，其次是骨髓中的低摄取。辐射剂量在可靠范围内。肿瘤摄取与PD-L1表达TPS呈正相关(rs = 0.8763, P = 0.019)。[68Ga]Ga-THP-APN09的肿瘤摄取(SUVmax)在MPR患者中高于非MPR患者(median SUVmax 2.73 vs. 2.10, P = 0.036, 使用Mann-Whitney U检验确定)。[68Ga]Ga-THP-APN09具有转化为基于试剂盒的放射性示踪剂的潜力，可用于快速、简单、一步、室温放射性标记。该示踪剂可以检测肿瘤中的PD-L1表达水平，可能预测PD-1免疫治疗联合化疗的响应。需要在大量病例中进行确认。 临床试验(NCT05156515)。登记日期：2021年12月12日。©2023.作者(们)已授予Springer-Verlag GmbH Germany的独家许可，该公司是Springer Nature的一部分。

Programmed cell death protein-1/ligand-1 (PD-1/L1) blockade has been a breakthrough in the treatment of patients with non-small cell lung cancer (NSCLC), but there is still a lack of effective methods to screen patients. Here we report a novel 68 Ga-labeled nanobody [68 Ga]Ga-THP-APN09 for PET imaging of PD-L1 status in mouse models and a first-in-human study in NSCLC patients.[68 Ga]Ga-THP-APN09 was prepared by site-specific radiolabeling, with no further purification. Cell uptake assays were completed in the human lung adenocarcinoma cell line A549, NSCLC cell line H1975 and human PD-L1 gene-transfected A549 cells (A549PD-L1). The imaging to image PD-L1 status and biodistribution were investigated in tumor-bearing mice of these three tumor cell types. The first-in-human clinical translational trial was registered as NCT05156515. The safety, radiation dosimetry, biodistribution, and correlations of tracer uptake with immunohistochemical staining and major pathologic response (MPR) were evaluated in NSCLC patients who underwent adjuvant immunotherapy combined with chemotherapy.Radiosynthesis of [68 Ga]Ga-THP-APN09 was achieved at room temperature and a pH of 6.0-6.5 in 10 min with a high radiochemical yield (> 99%) and 13.9-27.8 GBq/μmol molar activity. The results of the cell uptake study reflected variable levels of surface PD-L1 expression observed by flow cytometry in the order A549PD-L1 > H1975 > A549. In small-animal PET/CT imaging, H1975 and A549PD-L1 tumors were clearly visualized in an 8.3:1 and 2.2:1 ratios over PD-L1-negative A549 tumors. Ex vivo biodistribution studies showed that tumor uptake was consistent with the PET results, with the highest A549PD-L1 being taken up the most (8.20 ± 0.87%ID/g), followed by H1975 (3.69 ± 0.50%ID/g) and A549 (0.90 ± 0.16%ID/g). Nine resectable NSCLC patients were enrolled in the clinical study. Uptake of [68 Ga]Ga-THP-APN09 was mainly observed in the kidneys and spleen, followed by low uptake in bone marrow. The radiation dose is within a reliable range. Tumor uptake was positively correlated with PD-L1 expression TPS (rs = 0.8763, P = 0.019). Tumor uptake of [68 Ga]Ga-THP-APN09 (SUVmax) in MPR patients was higher than that in non-MPR patients (median SUVmax 2.73 vs. 2.10, P = 0.036, determined with Mann-Whitney U-test).[68 Ga]Ga-THP-APN09 has the potential to be transformed into a kit-based radiotracer for rapid, simple, one-step, room temperature radiolabeling. The tracer can detect PD-L1 expression levels in tumors, and it may make it possibility to predict the response of PD-1 immunotherapy combined with chemotherapy. Confirmation in a large number of cases is needed.Clinical Trial (NCT05156515). Registered 12 December 2021.© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.