[The Effecacy and Safety of Daratumumab Based Regimens in Relapsed/Refractory Multiple Myeloma: A Single-Center Real-World Data Analysis].

OBJECTIVE: To investigate the efficacy and safety of daratumumab based regimens in relapse and/or refractory multiple myeloma (RRMM) in the real world, as well as the impact of daratumumab on stem cell collection and engraftment. METHODS: The clinical data of patients with RRMM who received daratumumab in hematology department of the First Affiliated Hospital of Xiamen University from February 2019 to March 2023 and had evaluable efficacy were retrospective analysis. RESULTS: All 43 RRMM patients were treated with daratumumab-based combination regimens, including Dd, DVd, DRd, Dkd, DId, and Dara-DECP. With median follow-up time 10.1 (2.1-36.6) months, the best overall response rate (ORR) was 74.4% and a best complete response rate (CR) was 25.6%. 1-year overall survival rate (OS) was 84.5%. The most common severe hematologic adverse events (Grade>3) are 3/4 grade leukopenia（18.6%）, and the most common severe non-hematologic adverse events were infusion-related reactions (IRRs， 20.9%) and infections（7.0%）. Multivariate prognostic analysis showed that extramedullary infiltration was an independent adverse prognostic factor affecting OS （P =0.004）. The use of daratumumab has no effect on stem cell collection, or engraftment. CONCLUSION: Daratumumab is safe and effective in RRMM.

Combining triptolide with ABT-199 is effective against acute myeloid leukemia through reciprocal regulation of Bcl-2 family proteins and activation of the intrinsic apoptotic pathway.

Bcl-2 inhibitors display an effective activity in acute myeloid leukemia (AML), but its clinical efficacy as a monotherapy was limited in part owing to failure to target other antiapoptotic Bcl-2 family proteins, such as Mcl-1. In this context, the combination strategy may be a promising approach to overcome this barrier. Here, we report the preclinical efficacy of a novel strategy combining ABT-199 with triptolide (TPL), a natural product extracted from a traditional Chinese medicine, in AML. Combination treatment exhibited markedly increased cytotoxicity in leukemic cells irrespective of p53 status while largely sparing normal cells of the hematopoietic lineage. Moreover, co-administration of ABT-199 with TPL dramatically suppressed leukemia progression as well as prolonged animal survival in a xenograft AML model. The potentiated effect of ABT-199 and TPL against AML was associated with activation of the mitochondrum-related intrinsic apoptotic pathway through a mechanism reciprocally modulating Bcl-2 family proteins. In this case, TPL not only downregulated Mcl-1 but also upregulated proapoptotic BH3-only proteins, thereby overcoming the resistance toward ABT-199. Conversely, ABT-199 abrogated Bcl-2-mediated cytoprotection against TPL. Together, these findings suggest that the regimen combining TPL and ABT-199 might be active against AML by inducing robust apoptosis through reciprocal regulation of anti- and proapoptotic Bcl-2 family proteins, therefore providing a strong rationale for the clinical investigation of this combination regimen for the treatment of AML.