CAR T cells targeting Nectin-4 safely overcome resistance to anti-Nectin-4 antibody-drug conjugate in solid tumors

Chimeric antigen receptor T (CAR T) cells represent a promising therapeutic option for a variety of cancers, including solid tumors. Nectin-4 is a cell adhesion molecule expressed at different levels in many solid tumors, including breast and urothelial carcinoma (UC). Enfortumab vedotin (EV), an antibody-drug conjugate (ADC) against Nectin-4, has significantly improved survival in patients with metastatic UC. Skin adverse reactions are frequently observed due to Nectin-4 expression in the epidermis. Here, we developed second-generation CAR T cells against Nectin-4 (N4CART) with a scFv that does not recognize human Nectin-4 expressed in skin keratinocytes. To study the effects of N4CART cell therapy, we used preclinical models of cell-derived xenografts (CDX) and patient-derived xenograft (PDX) of breast cancer expressing moderate to high levels of Nectin-4. We showed a marked efficacy with induction of remissions. Interestingly, N4CART cells kill Nectin-4-positive breast, urothelial and colon tumor cells, which are resistant to EV. Thus, N4CART cells represent a valuable and safe therapy for the treatment of patients with Nectin-4 expressing tumors, including those that are resistant to EV. Finally, baboon-envelope pseudotyped lentiviral vectors (LV) outperformed VSVG-LVs for Nectin-4 CAR expressing in {beta} T cells resulting in an efficient anti-tumoral response in PDX mice.