Improved Chimeric Antigen Receptor Therapies B-cell Malignancies

在过去的一年中，我们设计并选择了一种针对CD19和CD20的最佳双频CAR结构。双频结构编码2个CAR，其中一个CAR是前面描述的Hu19-CD828Z CAR。第二种CAR是一种抗cd20 CAR，命名为Hu20-CD8BBZ。整个双链结构体被命名为Hu19-CD828-Hu20BB，该结构体由一个γ逆转录病毒载体编码。我们计划在2022年底开始一项针对CD19和CD20的双电子CAR设计的临床试验。我们花了大量的时间优化双链载体的DNA序列，以消除同源DNA序列驱动的缺失事件。我们已经在GMP条件下生产了一个优化的基因治疗载体。IND将很快提交给FDA。我们还制备了一种产生编码Hu19-CD828Z抗cd19 CAR的γ -逆转录病毒的生产细胞克隆。从这个主细胞库中产生了gmp级载体。我们计划在招募CLL患者的临床试验中使用该载体。在过去的一年里，我们花费了大量的时间和精力来准备这两项即将进行的临床试验所需的监管文件。我们还进行了实验来研究细胞因子对CAR毒性的影响，包括用于治疗CAR - T细胞对CAR - T细胞毒性的皮质类固醇的作用。

In the past year, we have designed and selected an optimal bicistronic CAR construct that targets both CD19 and CD20. The bicistronic construct encodes 2 CARs, one of the CARs is the previously -described Hu19-CD828Z CAR. The second CAR is an anti-CD20 CAR designated Hu20-CD8BBZ. The entire bicistronic construct is designated Hu19-CD828-Hu20BB, and the construct is encoded by a gammaretroviral vector. We plan to start a clinical trial with bicistronic CAR designs targeting CD19 and CD20 in late 2022. We have spent extensive time optimizing the DNA sequence of the bicistronic vector to eliminate deletion events driven by homologous DNA sequences. We have an optimized gene therapy vector that has been produced under GMP conditions. An IND will be submitted to the FDA very soon. We have also prepared a producer cell clone that generates a gamma-retrovirus encoding the Hu19-CD828Z anti-CD19 CAR. GMP-grade vector has been produced from this master cell bank. We plan to use this vector in a clinical trial that will enroll CLL patients. Substantial time and effort has been expended in the past year to prepare required regulatory documents for the two upcoming clinical trials. We have also carried out experiments to examine the impact of cytokines on CAR toxicity including the role of corticosteroids, which are used to treat CAR T-cell toxicity on CAR T cells.