BCMA-Targeted CAR T-cell Therapy plus Radiotherapy for the Treatment of Refractory Myeloma Reveals Potential Synergy

Abstract

We present a case of a patient with multiply relapsed, this response, which resembled cytokine-release syn-refractory myeloma whose clinical course showed evi-drome, immediately following XRT, we investigated dence of a synergistic abscopal-like response to chimeric changes in the patient's T-cell receptor (TCR) repertoire antigen receptor (CAR) T-cell therapy and localized radio-over 10 serial time points. Comparing T-cell diversity via therapy (XRT). Shortly after receiving B-cell maturation Morisita's overlap indices (CD), we discovered that, antigen (BCMA)–targeted CAR T-cell therapy, the patient although the diversity was initially stable after CAR T-cell required urgent high-dose steroids and XRT for spinal therapy compared with baseline (CD ¼ 0.89–0.97, base-cord compression. Despite the steroids, the patient had line vs. 4 time points after CAR T cells), T-cell diversity a durable systemic response that could not be attributed changed after the conclusion of XRT, with >30% newly to XRT alone. Post-XRT findings included a second wave expanded TCRs (CD ¼ 0.56–0.69, baseline vs. 4 time of fever and increased CRP and IL6, beginning 21 days points after XRT). These findings suggest potential synergy after CAR T cells, which is late for cytokine-release syn-between radiation and CAR T-cell therapies resulting in an drome from CAR T-cell therapy alone on this trial. Given abscopal-like response.