B‐cell maturation antigen chimeric antigen receptor T‐cell re‐expansion in a patient with myeloma following salvage programmed cell death protein 1 inhibitor‐based combination therapy.

Increase in the proportion of CAR T cells expressing PD-1 post-infusion, as we observed in our transient re-expander, warrants further exploration as a biomarker that could predict response to anti-PD1 therapy after CAR T cells. CAR-negative T cells also became activated (73% HLA-DR SP + sp , up from 20% at the day 28 time-point), suggesting non-specific T-cell activation by the Pembro/Elo/Pom/Dex combination. Nonetheless, this proof-of-principle observation that CAR T-cell activity can be modulated in patients with myeloma post-infusion supports further exploration of immune-modulating therapies such as checkpoint inhibitors in combination with CAR T cells. Keywords: myeloma therapy; cellular therapies; immunotherapy; T cells EN myeloma therapy cellular therapies immunotherapy T cells 851 855 5 05/17/21 20210515 NES 210515 Autologous T cells expressing a chimeric antigen receptor (CAR) specific for B-cell maturation antigen (BCMA) have demonstrated high response rates in refractory myeloma,1-3 but relapses remain common. [Extracted from the article]