Depletion of high-content CD14+ cells from apheresis products is critical for successful transduction and expansion of CAR T cells during large-scale cGMP manufacturing

• Published in: Molecular therapy. Methods & clinical development Vol. 22; pp. 377 - 387
• Main Authors: Wang, Xiuyan, Borquez-Ojeda, Oriana, Stefanski, Jolanta, Du, Fang, Qu, Jinrong, Chaudhari, Jagrutiben, Thummar, Keyur, Zhu, Mingzhu, Shen, Ling-bo, Hall, Melanie, Gautam, Paridhi, Wang, Yongzeng, Sénéchal, Brigitte, Sikder, Devanjan, Adusumilli, Prasad S., Brentjens, Renier J., Curran, Kevin, Geyer, Mark B., Mailankhody, Sham, O’Cearbhaill, Roisin, Park, Jae H., Sauter, Craig, Slovin, Susan, Smith, Eric L., Rivière, Isabelle
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 10.09.2021; American Society of Gene & Cell Therapy; Elsevier
• Subjects: CAR T cell; cGMP; clinical grade; large-scale manufacturing; monocyte depletion; Original; clinical grade; cGMP; monocyte depletion; large-scale manufacturing; CAR T cell
• ISSN: 2329-0501; 2329-0501
• DOI: 10.1016/j.omtm.2021.06.014

With the US Food and Drug Administration (FDA) approval of four CD19- and one BCMA-targeted chimeric antigen receptor (CAR) therapy for B cell malignancies, CAR T cell therapy has finally reached the status of a medicinal product. The successful manufacturing of autologous CAR T cell products is a key requirement for this promising treatment modality. By analyzing the composition of 214 apheresis products from 210 subjects across eight disease indications, we found that high CD14+ cell content poses a challenge for manufacturing CAR T cells, especially in patients with non-Hodgkin’s lymphoma and multiple myeloma caused by the non-specific phagocytosis of the magnetic beads used to activate CD3+ T cells. We demonstrated that monocyte depletion via rapid plastic surface adhesion significantly reduces the CD14+ monocyte content in the apheresis products and simultaneously boosts the CD3+ content. We established a 40% CD14+ threshold for the stratification of apheresis products across nine clinical trials and demonstrated the effectiveness of this procedure by comparing manufacturing runs in two phase 1 clinical trials. Our study suggests that CD14+ content should be monitored in apheresis products, and that the manufacturing of CAR T cells should incorporate a step that lessens the CD14+ cell content in apheresis products containing more than 40% to maximize the production success. [Display omitted] By analyzing 214 apheresis products and CAR T cell manufacturing runs across multiple disease indications, IR and colleagues have established a threshold of 40% CD14+ cell content as the trigger for the introduction of a rapid plastic adherence monocyte depletion step to enable a 97% manufacturing success rate.