背景:局部晚期/复发性头颈部鳞状细胞癌(HNSCC)与显著的发病率和死亡率相关。为了靶向在该癌症中上调的ErbB二聚体表达,我们开发了一种基于CD28的自体嵌合抗原受体T细胞(CAR-T)方法,称为T4免疫疗法。通过逆转录病毒转导对患者来源的T细胞进行工程改造,以共表达称为T1E28ζ的panErbB特异性CAR和IL-4反应性嵌合细胞因子受体,4αβ,这允许在制造期间IL-4介导的转导细胞的富集。这些细胞引发针对HNSCC和其他癌的临床前抗肿瘤活性。在这次审判中,由于健康组织中ErbB的低水平表达,我们使用肿瘤内给药,以减轻肿瘤外毒性的显著临床风险.
方法:我们进行了一项HNSCC瘤内T4免疫治疗的1期剂量递增3+3试验(NCT01818323)。CAR-T细胞批次是使用2周的半封闭工艺从40到130毫升的全血制造的。单一的CAR-T细胞治疗,在1-4毫升培养基中配制为新鲜产品,注射到一个或多个靶病变中。CART细胞的剂量在1×107-1×109T4+T细胞的5个队列中逐步增加,没有事先淋巴清除给药。
结果:尽管大多数受试者有基线淋巴细胞减少,在所有情况下都成功制造了靶细胞剂量,产生高达75亿个T细胞(67.5±11.8%转导),没有任何批处理失败。治疗相关的不良事件均为2级或以下,无剂量限制性毒性(不良事件通用术语标准V.4.0)。常见的治疗相关不良事件是肿瘤肿胀,疼痛,pyrexias,发冷,和疲劳。没有证据表明肿瘤内递送后T4+T细胞泄漏到循环中,和注射放射性标记的细胞证明肿瘤内的持久性。尽管进入试验时进展迅速,在CART细胞施用后6周,在15名受试者中的9名(60%)中观察到疾病的稳定(实体瘤V.1.1中的反应评价标准)。随后用pembrolizumab和T-VEC溶瘤病毒治疗在一名受试者中实现了快速完整的临床反应。这是持久的超过3年。中位总生存期大于历史对照。疾病稳定与免疫表型拟合剂的施用有关,更少的疲惫,T4CAR-T细胞产品。
结论:这些数据证明了T4免疫治疗在晚期HNSCC中的安全肿瘤内给药。
Locally advanced/recurrent head and neck squamous cell carcinoma (HNSCC) is associated with significant morbidity and mortality. To target upregulated ErbB dimer expression in this cancer, we developed an autologous CD28-based chimeric antigen receptor T-cell (CAR-T) approach named T4 immunotherapy. Patient-derived T-cells are engineered by retroviral transduction to coexpress a panErbB-specific CAR called T1E28ζ and an IL-4-responsive chimeric cytokine receptor, 4αβ, which allows IL-4-mediated enrichment of transduced cells during manufacture. These cells elicit preclinical antitumor activity against HNSCC and other carcinomas. In this
trial, we used intratumoral delivery to mitigate significant clinical risk of on-target off-tumor toxicity owing to low-level ErbB expression in healthy tissues.
We undertook a phase 1 dose-escalation 3+3
trial of intratumoral T4 immunotherapy in HNSCC (NCT01818323). CAR T-cell batches were manufactured from 40 to 130 mL of whole blood using a 2-week semiclosed process. A single CAR T-cell treatment, formulated as a fresh product in 1-4 mL of medium, was injected into one or more target lesions. Dose of CAR T-cells was escalated in 5 cohorts from 1×107-1×109 T4+ T-cells, administered without prior lymphodepletion.
Despite baseline lymphopenia in most enrolled subjects, the target cell dose was successfully manufactured in all cases, yielding up to 7.5 billion T-cells (67.5±11.8% transduced), without any batch failures. Treatment-related adverse events were all grade 2 or less, with no dose-limiting toxicities (Common Terminology Criteria for Adverse Events V.4.0). Frequent treatment-related adverse events were tumor swelling, pain, pyrexias, chills, and fatigue. There was no evidence of leakage of T4+ T-cells into the circulation following intratumoral delivery, and injection of radiolabeled cells demonstrated intratumoral persistence. Despite rapid progression at
trial entry, stabilization of disease (Response Evaluation Criteria in Solid Tumors V.1.1) was observed in 9 of 15 subjects (60%) at 6 weeks post-CAR T-cell administration. Subsequent treatment with pembrolizumab and T-VEC oncolytic virus achieved a rapid complete clinical response in one subject, which was durable for over 3 years. Median overall survival was greater than for historical controls. Disease stabilization was associated with the administration of an immunophenotypically fitter, less exhausted, T4 CAR T-cell product.
These data demonstrate the safe intratumoral administration of T4 immunotherapy in advanced HNSCC.