CRISPR-edited CART with GM-CSF knockout and auto secretion of IL6 and IL1 blockers in patients with hematologic malignancy

Yan Yi; Xiaoshan Chai; Liping Zheng; Yongjing Zhang; Jiankai Shen; Biliang Hu; Guangshi Tao

doi:10.1038/s41421-021-00255-4

CRISPR-edited CART with GM-CSF knockout and auto secretion of IL6 and IL1 blockers in patients with hematologic malignancy

Cell Discov. 2021 Apr 27;7(1):27. doi: 10.1038/s41421-021-00255-4.

Authors

Yan Yi^#^{1

2}, Xiaoshan Chai^#^{1

2}, Liping Zheng^{1

2}, Yongjing Zhang^{1

2}, Jiankai Shen¹, Biliang Hu^{3

4}, Guangshi Tao^{5

6}

Affiliations

¹ The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China.
² Hunan Key Laboratory of Tumor Models and Individualized Medicine, Changsha, Hunan, 410011, China.
³ Celledit, Worcester, MA, 01606, USA. bilianghu@celledit.com.
⁴ Siweikang Therapeutics, Changsha, Hunan, 410013, China. bilianghu@celledit.com.
⁵ The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China. taoguangshi@csu.edu.cn.
⁶ Hunan Key Laboratory of Tumor Models and Individualized Medicine, Changsha, Hunan, 410011, China. taoguangshi@csu.edu.cn.

^# Contributed equally.

Abstract

Revolutionary CART therapy still faces the challenge of severe cytokine release syndrome (CRS). While IL6 and IL1 have been demonstrated as essential contributors, GM-CSF is one of the most abundant inflammatory cytokines secreted by CART and has also been suggested in contributing to CRS. To minimize GM-CSF production from CART to reduce its associated toxicity, we conducted a pilot study (ChiCTR2000032124) of CRISPR-edited GM-CSF knockout (KO) in CART secreting anti-IL6 scFv and IL1RA, with additional TCR KO for tracing edited CART. The initial results of three patients (1 Non-Hodgkin lymphoma (NHL) and 2 multiple myelomas (MMs)) are summarized as: 3/3 complete response, 2/3 none CRS, 1/3 grade 2 CRS, and 0/3 neurotoxicity. The analysis revealed low levels of GM-CSF, IL6 and IL1B at the time of interferon-gamma (IFNG) peaks, and elevated IL1RA. We also observed significant expansion of CD3^- CART during treatment and no aberrant expansion of CD3^- CART in the follow-up. Re-expansion of CD3^- CART was observed in two patients while recurring CD19⁺ cells were eradicated in the patient with NHL. In summary, our study supported the safety and durable potency of CRISPR-edited CART in patients, providing a novel platform for developing autologous or allogeneic CART to minimize GM-CSF-associated toxicity in addition to autonomous IL6/IL1 blockade.