BCMA CAR-T therapy combined with pomalidomide is a safe and effective treatment for relapsed/refractory multiple myeloma.
B-cell maturation antigen (BCMA)-targeted chimeric antigen receptor T-cell (CAR T-cell) therapy has exhibited remarkable efficacy in refractory or relapsed multiple myeloma (R/R MM), but recurrence and rapid progression of disease are still observed within a short time after treatment. Long-term pomalidomide therapy, which potentiates T-cell functionality, might enhance the efficacy of BCMA CAR T-cell therapy.
We performed a single-center retrospective clinical study. Patients with relapsed or refractory multiple myeloma who received BCMA CAR T-cell infusion were enrolled in our study, and were followed by long-term pomalidomide treatment (4 mg/day) or not one month after infusion. The response and adverse events were assessed after infusion. The effect of pomalidomide on BCMA CAR T-cells was assessed in vitro.
The objective response rate (ORR) of BCMA-CART was 100%. Three months following CAR T-cell infusion, of the 8 patients receiving pomalidomide, except for 2 patients who stopped maintenance therapy and were lost to follow-up, all patients (6/6) achieved VGPR (very good partial response) or CR (complete response), while only 5 patients (5/8) who did not receive pomalidomide treatment achieved VGPR or better. At a median follow-up of 27 months, for the 8 patients who did not receive pomalidomide administration, the median TTP (time to progression) was 5.85 (1-14) months, while the OS (overall survival) was 10.7 (1.2-16) months. Of the 8 patients who received pomalidomide therapy after CAR T-cell infusion, the median TTP was 13 (7-13) months, while the OS was not reached. Moreover, neither long-term hematological toxicity nor drug-induced liver damage was observed during the follow-up period. Mechanistically, pomalidomide promotes antimyeloma efficacy of BCMA CAR T-cells by inhibiting cell apoptosis and enhancing cytoxicity.
Our results confirmed that BCMA CAR T-cell therapy combined with long-term pomalidomide had a low recurrence rate and manageable therapy-related side effects, providing a promising option for treating R/R MM.
Yan Y
,Tu Y
,Cheng Q
,Zhang J
,Wang E
,Deng Z
,Yu Y
,Wang L
,Liu R
,Chu L
,Kang L
,Liu J
,Li X
... -
《Journal of Translational Medicine》
Preclinical delayed toxicity studies of BCMA CAR T-cell injection in B-NDG mice with multiple myeloma.
Based on the efficacy data from the previous study of B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell injection, we further examined the delayed toxicity for 8 weeks after a single dose of BCMA CAR T-cell injection to observe possible toxic reactions.
B-NDG mice transplanted with multiple myeloma (MM) cells were given a single dose of BCMA CAR T-cell injection at two dosages or human normal T cells and then subjected to examinations including clinical signs, weight and food intake measurements, haematology, blood biochemical analysis, cytokine assay, T-lymphocyte subpopulation quantification and histopathology on days 28 and 56 after dosing. In addition, quantitative polymerase chain reaction (qPCR) was used to quantify DNA fragments in different tissues to assess the tissue distribution of CAR and provide a basis for its preclinical safety evaluation and clinical dosing.
In the delayed toxicity study, no mortality or significant toxic effects such as reductions in food intake, body weight, relevant biochemical parameters and target organ weights were observed in the BCMA CAR T-cell-treated groups. Compared to the model group, restorative changes in clinical signs and clinicopathology indicating therapeutic effects were seen in the BCMA CAR T-cell-treated groups. Human-derived cytokines interleukin-2 (IL-2), IL-4, IL-6, IL-12, IL-10, tumor necrosis factor α (TNF-α), and interferon-γ (IFN-γ) could be detected in all cancer cell-bearing mice by cytokine level measurement. IFN-γ levels showed a geometric increase due to the graft versus host disease (GVHD) response induced in the mice, while the levels of the other cytokines did not show significant changes. Histopathological examination indicated that the BCMA CAR T-cell treatment groups showed mixed cellular infiltration of human-derived T cells, cancer cells, and inflammatory cells in several target organs including the liver, spleen, lung, and kidney, and some of them showed mild tissue damage, but the number of the animals and the severity of damage were significantly less than those of the T-cell control group as well as the model group. The results of the tissue distribution study showed that BCMA CAR T cells were mainly concentrated in the kidney, lung, bone marrow and the related immune organs/tissues, and the distribution of BCMA CAR T cells was highly consistent with that of MM cells, suggesting that BCMA CAR T cells could follow the cancer cells during metastatic targeting of the tissues.
The present study demonstrated a low toxicity of BCMA CAR T-cell injection, with manageable side effects and good anticancer activity and without observable adverse effects. This study provides data to support future clinical studies of BCMA CAR T-cell injection for MM.
Guo J
,Wu Q
,Li H
,Liang C
,Dai J
,Zhang S
,Dai C
,Zhang J
,Wen Y
,Yang W
... -
《Frontiers in Immunology》