Les cellules CAR-T anti-CD19 : prototypes du médicament vivant

Abstract

Chimeric antigen receptors (CARs) are synthetic receptors that determine the specificity and functions of transduced T cells. They bind cell surface antigens through their extracellular domain and initiate via their intracellular domain cytolytic functions, cytokine secretion and proliferation. The CAR thus specifies the properties of a living drug that is programmed to exert anti-tumor and immunoregulatory effects.After establishing a method to stably integrate foreign genes in primary T lymphocytes in the early 1990s, we identified combinatorial signaling modules that could sustain a prolonged T cell function [17], which underpins an essential feature of a living drug. We further identified CD19 as a promising molecular target, which, based on encouraging preclinical results in mice [30], paved the way for clinical trials.The first clinical studies in patients with relapsed, refractory leukemias and lymphomas, which all made use of CAR T cells produced in the academic setting, yielded remarkable clinical response that were soon confirmed at several centers [2]. CAR T cells targeting CD19 were the first living drugs to be approved by the US Food and Drug Administration in 2017 and the European Medicines Agency in 2018.CD19 CARs have thus spawned a new class of drugs and inspired new applications to treat cancer and autoimmune diseases with engineered immune cells, warranting sustained efforts to lower their cost and increase their availability in equitable fashion.