Five-year remission without disease progression in a patient with relapsed/refractory multiple myeloma with extramedullary disease treated with LCAR-B38M chimeric antigen receptor T cells in the LEGEND-2 study: a case report.

BACKGROUND: Multiple myeloma remains incurable despite treatment advancements over the last 20 years. LCAR-B38M Cells in Treating Relapsed/Refractory Multiple Myeloma was a phase 1, first-in-human, investigator-initiated study in relapsed/refractory multiple myeloma conducted at four sites in China. The study used LCAR-B38M chimeric antigen receptor-T cells expressing two B-cell maturation antigen-targeting single-domain antibodies designed to confer avidity, and a CD3ζ signaling domain with a 4-1BB costimulatory domain to optimize T-cell activation and proliferation. This chimeric antigen receptor construct is identical to ciltacabtagene autoleucel. In the LEGEND-2 study (n = 57, Xi'an site), overall response rate was 88%; median (95% CI) progression-free survival and overall survival were 19.9 (9.6-31.0) and 36.1 (26.4-not evaluable) months, respectively; and median follow-up was 25 months. This case study reports on a patient with relapsed/refractory multiple myeloma (λ light chain type) who was treated with LCAR-B38M chimeric antigen receptor T cells in the LEGEND-2 study (Xi'an site); he had received five prior lines of treatment and had extensive extramedullary lesions. CASE PRESENTATION: The patient, a 56-year-old Asian male, received cyclophosphamide (500 mg daily × 3 days) as lymphodepletion therapy and a total dose of 0.5 × 106 chimeric antigen receptor + T cells/kg split into three infusions (days 1, 24, and 84 from June to August 2016). He experienced grade 2 cytokine release syndrome after the first infusion; all symptoms resolved with treatment. No cytokine release syndrome occurred following the second and third infusions. His λ light chain levels decreased and normalized 20 days after the first infusion, and extramedullary lesions were healed as of January 2018. He has sustained remission for 5 years and received no other multiple myeloma treatments after LCAR-B38M chimeric antigen receptor T cell infusion. As of 30 October 2020, the patient is still progression-free and has maintained minimal residual disease-negative (10-4) complete response status for 52 months. CONCLUSIONS: This case provides support that treatment with LCAR-B38M chimeric antigen receptor T cells can result in long-term disease remission of 5 or more years without disease progression in a heavily pretreated patient with extensive extramedullary disease and no other treatment options.

Four-year follow-up of LCAR-B38M in relapsed or refractory multiple myeloma: a phase 1, single-arm, open-label, multicenter study in China (LEGEND-2).

BACKGROUND: LCAR-B38M is a chimeric antigen receptor T cell product with two binding domains targeting B cell maturation antigen. Our previous reports showed a remarkable efficacy of LCAR-B38M in patients with relapsed/refractory multiple myeloma (RRMM) at a median follow-up of 2 years. Here, we report long-term safety and efficacy data from a median follow-up of 4 years. METHODS: LEGEND-2 was a phase 1, single-arm, open-label study conducted in four registered sites in China. Seventy-four participants with RRMM received LCAR-B38M treatment. Lymphodepletion was performed using cyclophosphamide or cyclophosphamide plus fludarabine. LCAR-B38M, at a median dose of 0.513 × 106 cells/kg, was intravenously administered either in three split infusions or in a single infusion. The primary objective was the safety of LCAR-B38M, and the secondary objective was efficacy. RESULTS: As of May 25, 2021, the median follow-up was 47.8 months. All patients experienced ≥ 1 adverse events (AEs). Grade ≥ 3 AEs were observed in 45/74 (60.8%) patients. Cytokine release syndrome (CRS) occurred in 68/74 (91.9%) cases; 7 (9.5%) had grade ≥ 3 CRS. One patient experienced grade 1 central nervous system toxicity. The overall response rate was 87.8%. Fifty-four out of 74 (73.0%) patients achieved complete response. The median progression-free survival was 18.0 months, and the median overall survival for all patients was not reached. The median duration of response was 23.3 months. Four patients experienced viral infection more than 6 months post-infusion, and four patients developed second primary non-hematological malignancies at a median time of 11.5 months post-CAR-T cell transfer. CONCLUSIONS: The 4-year follow-up data of LCAR-B38M therapy demonstrated a favorable long-term safety profile and a durable response in patients with RRMM. Trial registration Clinicaltrials.gov NCT03090659 (retrospectively registered on March 27, 2017); ChiCTR-ONH-17012285.

A phase 1, open-label study of LCAR-B38M, a chimeric antigen receptor T cell therapy directed against B cell maturation antigen, in patients with relapsed or refractory multiple myeloma.

BACKGROUND: Chimeric antigen receptor (CAR) T cell therapy has demonstrated proven efficacy in some hematologic cancers. We evaluated the safety and efficacy of LCAR-B38M, a dual epitope-binding CAR T cell therapy directed against 2 distinct B cell maturation antigen epitopes, in patients with relapsed/refractory (R/R) multiple myeloma (MM). METHODS: This ongoing phase 1, single-arm, open-label, multicenter study enrolled patients (18 to 80 years) with R/R MM. Lymphodepletion was performed using cyclophosphamide 300 mg/m2. LCAR-B38M CAR T cells (median CAR+ T cells, 0.5 × 106 cells/kg [range, 0.07 to 2.1 × 106]) were infused in 3 separate infusions. The primary objective is to evaluate the safety of LCAR-B38M CAR T cells; the secondary objective is to evaluate the antimyeloma response of the treatment based on the general guidelines of the International Myeloma Working Group. RESULTS: At data cutoff, 57 patients had received LCAR-B38M CAR T cells. All patients experienced ≥ 1 adverse events (AEs). Grade ≥ 3 AEs were reported in 37/57 patients (65%); most common were leukopenia (17/57; 30%), thrombocytopenia (13/57; 23%), and aspartate aminotransferase increased (12/57; 21%). Cytokine release syndrome occurred in 51/57 patients (90%); 4/57 (7%) had grade ≥ 3 cases. One patient reported neurotoxicity of grade 1 aphasia, agitation, and seizure-like activity. The overall response rate was 88% (95% confidence interval [CI], 76 to 95); 39/57 patients (68%) achieved a complete response, 3/57 (5%) achieved a very good partial response, and 8/57 (14%) achieved a partial response. Minimal residual disease was negative for 36/57 (63%) patients. The median time to response was 1 month (range, 0.4 to 3.5). At a median follow-up of 8 months, median progression-free survival was 15 months (95% CI, 11 to not estimable). Median overall survival for all patients was not reached. CONCLUSIONS: LCAR-B38M CAR T cell therapy displayed a manageable safety profile and demonstrated deep and durable responses in patients with R/R MM. TRIAL REGISTRATION: ClinicalTrials.gov , NCT03090659 ; Registered on March 27, 2017, retrospectively registered.

[Drug-Resistant Mechanism of Multiple Myeloma and Its Therapy Combined with HDACi -Review].

Drug resistance of multiple myeloma(MM) has become more and more common, and greatly decreased the survival rate of these patients. The occurence of drug-resistance involves in many factors such as bone marrow microenveronment, tumor cell self-metabolism, cytokines, specific targets and so on. In this review, the potential mechanisms of resistance to glucocorticoid/proteasome inhibitor/immunomodulatory druges are briefly expounded in the aspect of tumor cell self-metabolism, including the changes of heat slock protein expression, mRNA expression, related cytokine levels and down-regulation of thalidomid-effecting site CRBN expression. In this review, the researches on the effect of histone deacetylase inhibitors(HDACi) combined with glucocorticoid, proteasome inhibitors, immunomodulatory drugs and monoclonal antibodies on multiple myeloma, specially, drug-resistant multiple myeloma are also summarized.

Effect of granulocyte colony-stimulating factor priming combined with low-dose cytarabine and homoharringtonine in higher risk myelodysplastic syndrome patients.

As sensitization of leukemia cells with granulocyte colony-stimulating factor (G-CSF) can enhance the cytotoxicity of chemotherapy in myeloid malignancies, a pilot study was conducted in order to evaluate the effect of G-CSF priming combined with low-dose chemotherapy in patients with higher risk myelodysplastic syndrome (MDS). The regimen, G-HA, consisted of cytarabine (Ara-C) 7.5mg/m(2)/12h by subcutaneous injection, days 1-14, homoharringtonine (HHT) 1.5mg/m(2)/day by intravenous continuous infusion, days 1-14, and G-CSF 150mg/m(2)/day by subcutaneous injection, days 0-14. 56 patients were enrolled, 34 patients (61%, 95% confidence interval: 51.44-70.56%) achieved complete remission (CR). Median duration of neutropenia was 7days (ranging from 2 to 16days). Grade 1-2 nonhematologic toxicities were documented, including nausea and vomiting (5%), liver function abnormality (5%), and heart function abnormality (2%). No central nervous system toxicity was found. Mortality within the first 4 weeks was 4%. The G-HA regimen is effective in remission induction for higher risk MDS patients and well tolerated due to the acceptable toxicity in maintenance therapy in the patients who cannot undergo Hematopoietic cell transplantation (HCT).

[Comparison of the Effectiveness and Safety of Combined Chemotherapy with PEG-Asp for Treatment of ALL and T-NHL Patients].

OBJECTIVE: To explore the effectiveness and safety of combined chemotherapy with pegasparaginase (PEG-Asp) for treatment of patients with acute lymphoblastic leukemia (ALL) and T cell non-Hodgkin's lymphoma (T-NHL) patients. METHODS: A total of 62 ALL or T-NHL patients were diagnosed and treated in our department and were enrolled in this study. Among them, 22 patients received the combined chemotherapy with PEG-Asp, while the other 40 patients received the standard chemotherapy with L-asparaginase (L-Asp) as the control. Therapeutic effectiveness, adverse effects, duration and expense of hospitalization, treatment-related mortality and survival were evaluated and compared in 2 different groups. RESULTS: In group of combined chemotherapy with PEG-Asp, the overall response rate was 90.91% (20 cases), among them CR rate and PR rate are 77.27% (17 cases) and 13.64% (3 cases), respectively. In the group of standard chemotherapy with L-Asp, the overall response rate was 87.5% (35 cases), among them CR rate and PR rate were 72.5% (29 cases) and 15% (6 cases), respectively. The difference neither between PEG-Asp and L-Asp chemotherapy groups nor between ALL and T-NHL subgroups was significant (P > 0.05). The 6-month and 12-month overall survival rates were not significantly different between the PEG-Asp and L-Asp chemotherapy groups, respectively (P > 0.05). The adverse effects were identified as degree 1-2 according to the WHO criteria of drug toxicity. Neither the adverse effects identified as degree 3-4 nor the treatment-related death were observed. Expect for allergy and hyperglycaemia, the difference of side-effect incidence between the two groups were not significant (P > 0.05). The treatment for all the patients in PEG-Asp chemotherapy group was completed, while the treatment with L-Asp was completed only in 29 cases. Moreover, both average duration and expense of hospitalization after the combined chemotherapy were less than the control. CONCLUSION: With higher response rate, lower drug toxicity and allergy incidence, the combined chemotherapy with PEG-Asp can replace the standard chemotherapy with L-Asp in the treatment of ALL and T-NHL. The optimization of the combined chemotheropeutic protocols for more cases and long-term survival rates need to further and deeply explorate.

[Clinical Study of Non Hodgkin's Lymphoma Treated with Enhanced Chemotherapy Regimen and Increased Treatment Courses].

OBJECTIVE: To study the non-Hodgkin's lymphoma treated with enhanced chemotherapy regimen and increase of treatment courses, including number of treatment courses, short-term efficacy, long-term survival and safety. METHODS: All the 254 cases of NHL in our hospital from January 2004 to February 2014 received a variety of intensive enhanced chemotherapy regimen, such as CHOPE, MAED, MMED and TAED. The median number of treatment course was 14, including 8 in the 1st year, 4 in the 2nd and 2 in the 3rd. RESULTS: (1) In 254 assessable patients, 182 patients (71.7%) achieved complete responses (CR), 30 patients (11.8%) achieved partial responses (PR), 22 patients (8.7%) achieved stable disease (SD), 20 patients (7.9%) achieved progressive disease (PD), 212 patients (83.5%) achieved response rate (RR). The median time of following-up was 56.5 months, the overall survivals (OS) of 1, 3 and 5 years were 90.1%, 74.5% and 61.1% respectively, the median survival time was 69 months, and the disease-free survivals (DFS) were 81.8%, 65.4% and 54.7% respectively, the median DFS was 65 months. (2) In therapeutic effects at early phase, the 3-year OS of patients who achieved CR, PR, SD and PD were 92.2%, 56.0%, 20.2% and 0% respectively; The 5-year OS of patients who achieved CR through ≤4 cycle treatments and the 5-year OS of patients who achieved CR through >4 cycles treatments were 83.1% and 6.8%, their DFS were 72.4% and 0% respectively. (3) The relapse rates of patients who received < 6, 6-8, 9-10, 11-13, 14, 15 and 20 cycle treatments were 82.5%, 78.9%, 71.9%, 65.8%, 41.8%, 30.4% and 16.7%. The response rate (RR) of patients who received 6-8 traditional chemotherapy cycle as CHOP or CHOP-like regimen were 50%-60% and relapse rate > 70%. CONCLUSION: Compared with traditional chemotherapy regimens, the dose-escalated, intensive and modified chemotherapy regimen can significatly improve the therapeutic efficiency for patients with NHL, including CR, long-term survival rate, and a good tolerance for patients. The chemotherapy intensity has been confirmed to be an important factor that associated with therapeutic efficiency. On the conditions tolerated by patients, the number of treatment cycles for NHL patients can be increased at lest 14, with 8 in the first year, 4 in the second year and 2 in the third year. The increase of chemotherapy cycle can obviously reduce the relapse rate and improve the long-term prognosis of patients. It is worth to further explore.

[Cohort Study on GHA and New Combined Priming Chemotherapeutic Regimens in Treatment of Refractory Acute Myeloid Leukemia and Myelodysplastic Syndrome].

OBJECTIVE: To explore the clinical efficacy and adverse effects of GHA(G-CSF+homoharringtonin+cytarabine C) and new combined priming chemotherapeutic regimens(GHAA/GHTA) with high efficacy and low toxicity for treatment of relapsed and refractory acute myeloid leukemia(AML) and myelodysplastic syndrome(MDS), and to analyze the relation of above-mentioned regimens with the expression of co-stimuolating molecule B7.1. METHODS: Standard GHA regimen consisting of G-CSF: 100 µg/(m2·d) subcutaneous injection, d 0-14; homoharringtonine: 1.0 mg/(m2·d) intravenous drip, d 1-14; Ara-C: 7.5-10 mg/(m2·d) subcutaneous injection, q12h, d 1-14. Other regimens as GHAA/GHTA were combined respectively with aclarubicin 20 mg d 1-7, or pirarubicin 20 mg d 1-7. 74 patients with refractory AML and 46 patients with MDS received these priming chemotherapy. The clinical efficacy and toxicity of above-mentioned priming chemotherapy were compared with 56 patients received routine chemotherapy (MA/TAE) respectively. And the expression of costimulatory molecule B7.1 on leukemia cells in patients of different subtypes was also detected by immunofluoressence and its relationship with clinical efficiency was explored. RESULTS: (1) for AML patients treated with priming chemotherapy, the total remission was 67.56% (CR 54.05%, PR 13.51%), which was much higher than that of patients received routine chemotherapy (P<0.05). The CR rate of AML-M2 and AML-M5 group (65.51%, 61.90% respectively) was much higher than that of AML other subtypes (P<0.05), and the longest remission period lasted for 4 years; (2) for MDS patients treated with priming chemotherapy, the total remission was 60.87% (CR 45.65%, PR 15.22%), which was also significantly higher than that of patients received routine chemotherapy (P<0.05); (3) in comparison with patients received standard GHA priming regimen, the remission rate of combined priming chemotherapy GHAA/GHTA was significantly higher both in patients with AML (85.18%) and MDS (81.25%); (4) side effects after chemotheropy, including granulocyte deficiency, thrombocytopenia and anemia etc, lasted for 7-14 days; the severe infection rate was 1%, there were no severe bleeding, digest effect and damage of function in heart, liver and kidney. The therapy-related mortality was zero. Compared with routine chemotherapy, priming chemotherapy proved significantly safe and effective (P<0.05); (5) the expression rate of costimulatory molecule B7.1 showed large variance between AML and MDS, it was higher in AML-M2/AML-M5 and lower in AML of other subtypes (P<0.05). In the same case, B7.1 expression was positive correlated with efficiency of priming chemotherapy. CONCLUSION: GHA priming chemotherapy, as well as other combination regimens GHAA/GHTA, are well-tolerated, effective regimens for refractory AML and advanced MDS, without severe side effects and therapy-related mortality. Especially the new regimens GHAA/GHTA has better efficacy, which are proved more efficient than conventional GHA. Efficiency of priming chemotherapy is positive correlated with B7.1 expression, its mechanism will be further explored.

The expression and functional characterization associated with cell apoptosis and proteomic analysis of the novel gene MLAA-34 in U937 cells.

MLAA-34 is a novel acute monocytic leukemia (M5)-associated antigen (MLAA) that plays a role in the apoptosis of U937 cells. However, the expression and molecular mechanism of MLAA-34 in U937 cells remain largely unclear. Here, we utilized three strategies to gain insight into the expression and molecular functions of MLAA-34 and to identify its interacting proteins and pathways involved in the fine-tuning of the MLAA-34 response. Western blot analysis was performed to assess the expression of MLAA-34 in 41 cell lines and five mixed cell types, which revealed that MLAA-34 is most strongly expressed in U937 cells. Immunostaining indicated that MLAA-34 is localized in the cytoplasm and cell membrane. Furthermore, lentivirus-mediated overexpression of MLAA-34 in the U937 cell line led to significant suppression of apoptosis and increased the potential of tumorigenicity. Co-immunoprecipitation (Co-IP), shotgun and bioinformatic analysis identified 256 proteins and 225 of them were annotated by gene ontology categories. This analysis revealed 71 proteins involved in cell apoptosis or proliferation of biological processes and signaling pathways. Moreover, the effect of MLAA-34 apoptosis may be through interaction with the Ras, Wnt, calcium and chemokine signaling pathways and thirteen of the annotated proteins may interact with MLAA-34 and participate in carcinogenesis directly. This study provides a basis for a better understanding of the molecular mechanism and proteomics in the inhibition of apoptosis by MLAA-34 in U937 cells and indicates that MLAA-34 may be a potential candidate for the early diagnosis and therapeutic application of M5.

Low dose of homoharringtonine and cytarabine combined with granulocyte colony-stimulating factor priming on the outcome of relapsed or refractory acute myeloid leukemia.

BACKGROUND: To explore the effect of low dose of homoharringtonine (HHT) and cytarabine (Ara-c) combined with granulocyte colony-stimulating factor (G-CSF) priming (HAG regimen) on relapsed or refractory acute myeloid leukemia (AML). METHODS: Sixty-seven patients with relapsed or refractory acute myeloid leukemia (AML) were enrolled. All the patients were treated with HAG regimen (HHT 1.5 mg/m(2)/day, 1-14d; Ara-C 7.5 mg/m(2)/12 h, 1-14d; G-CSF 150 µg/m(2)/day, according to the counting of the peripheral white blood cells). Blood cell counting, liver, kidney function, ECG and myocardial enzymes were monitored regularly. RESULTS: Thirty-five of 67 (52.2%) patients achieved complete remission (CR) and 8/67 (11.9%) partial remission (PR). The overall response rate was 64.1%. Myelosuppression was the most frequently observed adverse effect. Sixty of 67 (89.5%) patients suffered from grade 1-4 adverse effects of hematologic toxicity (according to World Health Organization criteria) and non-hematologic toxicity was mild. CONCLUSION: In conclusion, HAG regimen was effective and tolerated well in refractory or relapsed AML. As a promising regimen for relapse or refractory AML, further observations should be made.