Metoprolol treatment minimally affects CAR T efficacy and cardiovascular function in patients. (A) The CONSORT flow diagram of the trial NCT04082910. (B–D) Heart rate (B), systolic blood pressure (SBP; C), and diastolic blood pressure (DBP; D) in patients who received metoprolol treatments (n = 16) were monitored at the indicated time points before and after CAR T infusion; the changes over the basal level at day 0 were calculated and shown. (E) Schematic depiction of metoprolol and non-metoprolol groups in the patients who received tandem CAR T therapy. (F and G) Response rate (F) and progression-free survival (G) after CAR T infusion in the patients who received metoprolol (n = 16) or not (n = 72) were monitored. (H) Peak absolute number of circulating tandem CAR T cells were determined by flow cytometry in patients who received metoprolol (n = 16) or not (n = 72). (I) Schematic depiction of single-cell sequencing for bone marrow mononuclear cells from patient #3. (J) UMAP projection of bone marrow mononuclear cells from patient #3. Monocyte/macrophages, T cells, and B cells were indicated. (K) Percentages of monocyte/macrophages, T cells, B cells, and other cells in bone marrow mononuclear cells from patient #3 were shown. (L) Changes in the percentages of T cells, B cells, and monocytes/macrophages in bone marrow mononuclear cells from patient #3 before and after metoprolol treatment are shown. Data are presented as mean ± SEM in B–D; ns, not significant; Mantel-Cox test in G; two-tailed unpaired t test in H. Each data point in H represents one individual patient.