International Myeloma Working Group consensus criteria for response and minimal residual disease assessment in multiple myeloma

Evaluation of Clinical Characteristics and Prognostic Factors of Early Progressive Disease (EPD) in Newly Diagnosed Multiple Myeloma Patients: Real-World Data of the Greek Myeloma Study Group

BACKGROUND

Despite treatment improvements a considerable proportion of newly diagnosed multiple myeloma (MM) patients experience early progressive disease (EPD) defined as progression or relapse in < 18 months following initial response to first line treatment.

METHODS

We evaluated 1436 newly diagnosed MM patients out of whom 23.3% had EPD.

RESULTS

Patients with EPD had higher median age, β2-microglobulin, LDH and lower hemoglobin and eGFR, compared to others (P < .05); EPD population presented more commonly with advanced stage (ISS3, RISS3, and R2-ISS stage III/IV). Ultra-high-risk MM (UHR-MM) i.e., detection of ≥ 2 high-risk molecular abnormalities was more frequent in EPD population (P < .001). The percentage of patients treated with lenalidomide-based regimens was not significantly different. Daratumumab-based therapies (DBT) were administered less frequently in patients with EPD (2% vs. 10%; P < .001); 11% of patients with EPD versus 33% underwent ASCT (P < .001); Complete response to induction therapy was significantly lower in EPD patients (12% vs. 27%; P < .001). Binary logistic regression analysis demonstrated that ISS, RISS, R2-ISS, UHR-MM, ASCT and DBT were significant predictors for EPD (P < .05). In multivariate analysis R2-ISS, ASCT, and DBT were independent prognosticators for EPD (P < .001). Median PFS and OS were 10 versus 40 months and 29 versus 76 months in patients with EPD versus others, respectively (P < .001).

CONCLUSION

In real-world, EPD is observed in more than one-fifth of patients, and it remains an unmet clinical need. Daratumumab-based therapies and ASCT significantly reduce the probability of EPD, while R2-ISS could serve as a useful prognostic tool for recognizing this population and guide therapeutic decisions.

Minimally Invasive Assessment of Peripheral Residual Disease During Maintenance or Observation in Transplant-Eligible Patients With Multiple Myeloma

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.In multiple myeloma (MM), measurable residual disease (MRD) is assessed in bone marrow (BM). However, less invasive evaluation of peripheral residual disease (PRD) in blood could be advantageous and less cumbersome. We investigated the prognostic value of PRD monitoring after 24 cycles of maintenance in 138 transplant-eligible patients with MM enrolled in the GEM2012MENOS65/GEM2014MAIN clinical trials. PRD was assessed using next-generation flow (NGF) and mass spectrometry (MS). Positive PRD by NGF in 16/138 (11.5%) patients was associated with a 13-fold increased risk of progression and/or death; median progression-free survival (PFS) and overall survival (OS) were 2.5 and 47 months, respectively. Considering patients' MRD status in BM as the reference, PRD detection using NGF showed positive and negative predictive values of 100% and 73%, respectively. Presence of PRD helped identifying patients at risk of imminent progression among those with positive MRD in BM. Patients with undetectable PRD according to both NGF and MS showed 2-year PFS and OS rates of 97% and 100%, respectively. In multivariate analyses including the Revised International Staging System and the complete remission status, only MRD in BM and PRD by NGF showed independent prognostic value for PFS. This study supports the use of less invasive PRD monitoring during maintenance or observation in transplant-eligible patients with MM.

CD27-Armored BCMA CAR T-cell Therapy (CBG-002) for Relapsed and Refractory Multiple Myeloma: A Phase I Clinical Trial

B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell therapy has been approved for the treatment of relapsed and refractory multiple myeloma (RRMM); however, whether patients have long-term responses has yet to be established. We investigated the feasibility of CBG-002, a CD27-armored BCMA CAR T-cell therapy, to improve clinical efficacy in patients with RRMM. We present preclinical data showing the activity of CBG-002 against myeloma and results from a phase I clinical trial (NCT04706936) evaluating its safety and efficacy in patients with RRMM. The primary endpoint was safety, as assessed by grade 3 or 4 adverse events (AE). Key secondary endpoints were overall response rate (ORR), duration of response (DOR), progression-free survival (PFS), and overall survival (OS). A total of 11 patients were enrolled and received CBG-002 therapy. Nine patients developed grade 1 or 2 cytokine release syndrome (CRS), whereas no patients experienced grade 3 or higher CRS or immune effector cell-associated neurotoxicity syndrome. Other grade 3 or higher AEs included neutropenia (72.7%), thrombocytopenia (45.5%), and anemia (36.4%). At a median follow-up of 16.7 months, the ORR was 81.8%, including a stringent complete response/complete response rate of 45.5%, very good partial response rate of 18.2%, and partial response rate of 18.2%, with a median DOR of 8.9 (range 1.8-21.9) months. The median OS was not reached, and the median PFS was 8.5 (2.7-22.9) months. In this phase I study, CBG-002, a CD27-armored BCMA CAR T-cell therapy, demonstrated safety and clinical efficacy in patients with RRMM.

Analysis of early efficacy and immune reconstitution after autologous hematopoietic stem cell transplantation in multiple myeloma

This retrospective study aimed to stress the advantages of autologous hematopoietic stem cell transplantation (auto-HSCT) in treating primary MM. Ninety-four MM patients who underwent initial parallel sequential auto-HSCT were selected. Data on efficacy (efficacy evaluation, renal function and hemoglobin recovery), immune reconstitution (B-cell subsets, immunoglobulin levels, T-cell subsets, NK cells, neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR)) and hematopoietic reconstitution times were collected and analyzed. Whether in all selected patients or in groups R-ISS II-III, there was a notable increase in the proportion of patients achieving in a very good partial response (VGPR) or better (P < 0.001, P = 0.02) and a complete response (CR) or better (P = 0.007, P = 0.014) after transplantation compared to the pre-transplant status. Post-Transplant Immune Reconstitution Analysis (Baseline vs. Pre-Transplant and Pre-Transplant vs. Post-Transplant): The level of CD19 + B cells, CD20 + B cells, CD22 + B cells, CD3 + T cells, IgG and LMR showed the same change trend, that is, it decreased before transplantation (P < 0.001, P < 0.001, P < 0.001, P < 0.001, P<0.007, P < 0.001) and then increased significantly after transplantation(P < 0.001, P < 0.001, P < 0.001, P < 0.001, P < 0.001, P < 0.001). CD3 + CD4 + T cells from 545.97 (342.11,708.60)/µL to 342.93 (168.38, 475.52)/µL (P < 0.001) and then to 251.48 (188.52, 406.98)/µL (P = 0.348); CD3 + CD8 + T cells from 391.36 (242.19, 563.37)/µL to 337.23 (192.54, 505.96)/µL (P = 0.065) and then to 797.96 (514.49, 1198.03)/µL (P < 0.001), so the CD3 + CD4+/CD3 + CD8 + T cell ratio still remained inverted post-transplant. NK cells changed from 309.86 (206.33, 460.96)/µL to 258.31 (160.75, 436.68)/ µL (P = 0.229) and then to 151.08 (108.17, 240.84)/µL (P = 0.007). Auto-HSCT can promote prolonged remission in patients with MM and also overcome some high-risk factors to achieve superior efficacy in group R-ISS II-III. Patients were immunodeficient before transplantation and auto-HSCT facilitated immune reconstitution.

Iberdomide, ixazomib and dexamethasone in elderly patients with multiple myeloma at first relapse

Most transplant-ineligible patients present with multiple myeloma (MM) refractory to lenalidomide and/or anti-CD38 monoclonal antibody at first relapse and represent a difficult-to-treat population. The Intergroupe Francophone du Myélome phase 2 study iberdomide, ixazomib and dexamethasone (I2D) evaluated the oral triplet iberdomide, ixazomib and dexamethasone in MM patients aged ≥70 years at first relapse (NCT04998786). Seventy patients were enrolled to receive iberdomide (1.6 mg on day 1-21), ixazomib (3 mg on day 1, 8, 15) and dexamethasone (20 mg on day 1, 8, 15, 22 on cycle 1-2 and 10 mg on day 1, 8, 15, 22 on cycle 3-6) (28-day cycle) until disease progression. Median age was 76; 50% patients were frail according to the International Myeloma Working Group frailty score; 74% and 37% were refractory to lenalidomide and daratumumab respectively. With a median follow-up of 14 months, the overall response rate was 64%, including 36% very good partial response or better. The 12-month progression-free survival, duration of response and overall survival were 52%, 76% and 86% respectively. The most common (46%) grade 3-4 toxicity was neutropenia. Non-haematological adverse events were mostly grade 1 or 2. Overall, I2D demonstrated a favourable risk-benefit profile in elderly MM patients at first relapse, including in patients with lenalidomide and daratumumab refractory disease.

Safety and efficacy of standard-of-care ciltacabtagene autoleucel for relapsed/refractory multiple myeloma

ABSTRACT

Ciltacabtagene autoleucel (cilta-cel) was approved in 2022 for patients with relapsed/refractory multiple myeloma (RRMM). We report outcomes with cilta-cel in the standard-of-care setting. Patients with RRMM who underwent leukapheresis for cilta-cel manufacturing between 1 March 2022 and 31 December 2022 at 16 US academic medical centers were included. Overall, 255 patients underwent leukapheresis and 236 (92.5%) received cilta-cel, of which 54% would not have met CARTITUDE-1 eligibility criteria. In treated patients (N = 236), cytokine release syndrome was seen in 75% (grade ≥3, 5%), immune effector cell-associated neurotoxicity syndrome in 14% (grade ≥3, 4%), and delayed neurotoxicity in 10%. Overall and complete response rates were as follows: all patients who received cilta-cel (N = 236), 89% and 70%; patients receiving conforming cilta-cel (n = 191), 94% and 74%; and conforming cilta-cel with fludarabine/cyclophosphamide lymphodepletion (n = 152), 95% and 76%, respectively. Nonrelapse mortality was 10%, most commonly from infection. After a median follow-up of 13 months from cilta-cel, the median progression-free survival (PFS) was not reached, with 12-month estimate being 68% (95% confidence interval, 62-74). High ferritin levels, high-risk cytogenetics, and extramedullary disease were independently associated with inferior PFS, with a signal for prior B-cell maturation antigen-targeted therapy (P = .08). Second primary malignancies excluding nonmelanoma skin cancers were seen in 5.5% and myeloid malignancies/acute leukemia in 1.7%. We observed a favorable efficacy profile of standard-of-care cilta-cel in RRMM, despite more than half the patients not meeting the CARTITUDE-1 eligibility criteria.

Real-World Evidence on Prognostic Value of MRD in Multiple Myeloma Using Flow Cytometry

Minimal residual disease (MRD) is one of the most important prognostic factors in multiple myeloma (MM) and a valid surrogate for progression-free survival (PFS) and overall survival (OS). Recently, MRD negativity was approved as an early clinical endpoint for accelerated drug approval in MM. Nevertheless, there is limited evidence of MRD utility in real-world setting. In this retrospective multicenter study, we report outcomes of 331 newly diagnosed MM patients with MRD evaluation at Day+100 after autologous stem cell transplantation using flow cytometry with a median limit of detection of 0.001%. MRD negativity was reached in 47% of patients and was associated with significantly prolonged median PFS (49.2 months vs. 18.4 months; hazard ratios (HR) = 0.37; p < 0.001) and OS (not reached vs. 74.9 months; HR = 0.50; p = 0.007). Achieving MRD negativity was associated with PFS improvements regardless of age, International Staging System (ISS) stage, lactate dedydrogenase (LDH) level, or cytogenetic risk. Importantly, MRD positive patients benefited from lenalidomide maintenance versus no maintenance (18-months PFS: 81% vs. 46%; HR = 0.24; p = 0.002) while in MRD negative patients such benefit was not observed (p = 0.747). The outcomes of our real-world study recapitulate results from clinical trials including meta-analyses and support the idea that MRD positive patients profit more from lenalidomide maintenance than MRD negative ones.

Targeting CLK2 and serine/arginine-rich splicing factors inhibits multiple myeloma through downregulating RAE1 by nonsense-mediated mRNA decay mechanism

Multiple myeloma (MM) is closely related to abnormal RNA splicing in its pathogenesis. CDC2-like kinase-2 (CLK2) regulates RNA splicing by phosphorylating serine/arginine-rich splicing factors (SRSFs), but the role of CLK2 in MM remains undefined. This study was to explore the role and mechanism of CLK2 in MM. Analyzing GEO datasets of MM patients found that high CLK2 expression predicted poor prognosis. Overexpression of CLK2 promoted the cell proliferation and cell cycle progression of MM cell ARP1 and H929. Knockdown or inhibition of CLK2 suppressed cell proliferation and induced cell apoptosis and cell cycle arrest in ARP1 and H929 cells in vitro. An MM xenograft tumor experiment showed that CLK2 overexpression promoted tumor growth, while CLK2 inhibition suppressed tumor growth in vivo. Mechanistic studies revealed that interfering CLK2 inhibited SRSF phosphorylation, and induced exon 9 skipping of RAE1, resulting in nonsense-mediated mRNA decay (NMD) of RAE1. In addition, RAE1 knockdown inhibited cell proliferation in ARP1 and H929 cells. Moreover, RAE1 overexpression promoted cell proliferation and cell cycle progression of ARP1 and H929 cells, and partially reversed the antitumor effect of CLK2 knockdown. Targeting CLK2 shows antitumor effects on MM partially through inhibiting SRSF phosphorylation and inducing NMD of RAE1. Therefore, targeting the CLK2/SRSFs/RAE1 axis could be a potential therapeutic strategy for MM.

The characteristics of Korean elderly multiple myeloma patients aged 80 years or over

BACKGROUND/AIMS

Multiple myeloma (MM) predominantly affects elderly individuals, but studies on older patients with MM are limited. The clinical characteristics and survival outcomes of patients with MM aged 80 years or over were retrospectively analyzed.

METHODS

This retrospective multicenter study was conducted to investigate the clinical characteristics, treatment patterns, and survival outcomes of patients aged 80 years or over who were newly diagnosed with MM at five academic hospitals in Daegu, Korea, between 2010 and 2019.

RESULTS

A total of 127 patients with a median age of 83 years (range, 80-93 yr) were enrolled: 52 (40.9%) with Eastern Cooperative Oncology Group Performance Status (ECOG PS) > 2, 84 (66.1%) with International Staging System (ISS) stage III disease, and 93 (73.2%) with a Charlson comorbidity index (CCI) > 4. Chemotherapy was administered to 86 patients (67.7%). The median overall survival was 9.3 months. Overall survival was significantly associated with ECOG PS > 2 (HR 2.26, 95% CI 1.43-3.59), ISS stage III (HR 1.99, 95% CI 1.18-3.34), and chemotherapy (HR 0.34, 95% CI 0.21-0.55). There was no statistically significant difference in event-free survival according to the type of anti-myeloma chemotherapy administered. The early mortality (EM) rate was 28.3%.

CONCLUSION

Even in patients with MM aged 80 years or over, chemotherapy can result in better survival outcomes than supportive care. Patients aged ≥ 80 years should not be excluded from chemotherapy based on age alone. However, reducing EM in elderly patients with newly diagnosed MM remains challenging.

A Pilot Study of UM171-Expanded Cord Blood Grafts for Tandem Auto/Allogeneic Hematopoietic Cell Transplant in High and Ultra-High-Risk Myeloma Patients

Multiple myeloma (MM) remains associated with a poor outcome, particularly in patients with advanced disease and high-risk (HR) cytogenetics. To date, the only curative treatment is allogeneic (allo) hematopoietic cell transplantation (HCT), but high incidences of graft versus host disease (GVHD), nonrelapse mortality (NRM) and disease progression remain important obstacles. Cord blood (CB) transplantation has been associated with low rates of relapse and chronic (c) GVHD, but its use has declined because of high incidences of infections, severe acute GVHD and high NRM. In other hematologic malignancies, UM171-expanded CB transplants have led to improved outcomes, allowing for the selection of smaller, better HLA-matched units. We aimed to investigate the safety and feasibility of single UM171-expanded single CB unit transplantation in frontline tandem auto/allo HCT for HR/ultra-HR MM patients. Newly diagnosed MM patients ≤ 65 years with an ISS stage II/III and del(17p), t(4;14), t(14;16), t(14;20), del(1p) or +1q, R-ISS 3, ≥ 2 cytogenetic abnormalities, or plasma cell leukemia without a sibling donor and availability of a 5-7/8 matched CB graft with ≥ 0.5 x 105 CD34+/kg and ≥ 1.5 x 107 TNCs/kg were eligible to this phase I/II prospective study (ClinicalTrials.gov NCT03441958). After induction and autologous HCT, patients received a reduced intensity conditioning regimen and were infused with 7-day UM171-expanded CD34+ cells, along with the lymphocytes contained in the CD34-negative fraction. The primary endpoints were feasibility of UM171 expansion, safety, kinetics of engraftment, incidences and maximum grades of acute and cGVHD at 1 and 2 years, assessment of measurable residual disease (MRD) and quality of life (QoL). Between 05/2018 and 11/2021, 20 patients were enrolled. One patient had an unsuccessful CB expansion with UM171, leaving 19 patients with a median age of 56 years. Median CD34+ cell dose infused after expansion was 4.62 x 106/kg (range: 0.79 to 5.76). Median times to achieve absolute neutrophil counts of 0.1 and 0.5 x 109/L were D+6 and D+10.5; median time to reach ≥ 20 x 109/L platelets was D+36. Full donor chimerism was achieved in all cell lineages by D+120 in recipients of reduced intensity conditioning. Cumulative incidences of grade II-IV, grade III-IV acute GVHD and moderate/severe cGVHD at 12 months were 68.4% (95% CI: 46 to 90), 5.3% (95% CI: 0% to 16%), and 10.5% (95% CI: 0% to 25%), respectively. With a median follow-up of 2.9 years (range: 0.46 to 5.3), cumulative incidences of relapse, PFS, OS and NRM at 3 years were 36.8% (95% CI: 14 to 59), 47.4% (95% CI: 29 to 76), 68.4% (95% CI: 50 to 93) and 15.8% (95%CI: 0 to 33), respectively. Median time to complete immunosuppression discontinuation was D+238. No unexpected adverse events were observed. Only one of 7 patients alive at 2 years with negative MRD at transplant has relapsed. Non-relapsing patients had a QoL after transplant similar to the general population. UM171-expanded CB transplant in HR/ultra-HR myeloma patients is feasible and allows the use of single CB units with a low risk of cGVHD. Patients with negative pretransplant MRD might benefit most from a UM171-expanded CB transplant.

Flow Cytometric MRD Detection in Selected Mature B-Cell Malignancies

The quantification of submicroscopic minimal residual disease (MRD) after therapy proved to have independent prognostic significance in many mature B-cell malignancies. With the advent of routine benchtop cytometers capable of simultaneously analyzing ≥8 colors and with improved standardization, flow cytometry has become the method of choice for MRD assessments in some lymphoma entities. Herein we describe general aspects of flow cytometric standardization. Chronic lymphocytic leukemia (CLL) and multiple myeloma (MM) are used as examples to explain the technical standardization of flow cytometry for MRD detection according to EuroFlow strategies. MRD data acquisition and detailed analysis in MM and CLL is a particular focus of this chapter.

Bortezomib With High-dose Melphalan Conditioning Regimen in Newly Diagnosed Multiple Myeloma Patients: Long-term Follow-up

BACKGROUND/AIM

Autologous stem cell transplantation (ASCT) is the standard strategy after induction therapy for newly diagnosed transplant-eligible multiple myeloma. High-dose melphalan (HDM) conditioning has been the recommended treatment regimen for a long time. No other conditioning regimen has been proven safer and more effective. Because bortezomib has a synergistic effect with melphalan, bortezomib with HDM (Bor-HDM) as a conditioning regimen has shown favorable outcomes, improved complete response rates after ASCT, and no prolonged hematological toxicities. However, few studies have reported long-term follow-up data. This study aimed to evaluate the long-term progression-free survival (PFS) and overall survival (OS) of patients receiving Bor-HDM conditioning, compared to those treated with HDM alone.

PATIENTS AND METHODS

This single-center retrospective study included 36 patients newly diagnosed with transplant-eligible myeloma from 2008 to 2020. In total, 15 patients received a Bor-HDM regimen, while 21 patients received HDM as a conditioning regimen. The probabilities of PFS and OS were plotted using the Kaplan-Meier method. All statistical analyses were performed using EZR software.

RESULTS

After a median follow up of 77 months, no severe hematological toxicities were observed. The PFS and OS rates in the Bor-HDM group as compared with the HDM group were 0.762 vs. 0.60 (p=0.409) and 0.80 vs. 0.904 (p=0.476) respectively. No significant differences were observed between the two groups.

CONCLUSION

These long-term results show that Bor-HDM is a safe and effective option for ASCT conditioning regimens.

Optimizing multiple Myeloma clinical trials: research direction, addressing limitations, and strategies for improvement

Despite significant advancements in multiple myeloma (MM) treatment, including novel therapies and combination strategies, the translation of findings from randomized controlled trials (RCTs) into real-world clinical practice has been associated with several challenges. Specifically, the principles and criterion that shape the current design of MM RCTs have left out a sizable portion of patients that would particularly benefit from trial inclusion. In addition, RCTs may use primary outcomes which only partially cover patient-relevant endpoints important for evaluating treatment efficacy and quality of life. In this review, we explore the current MM RCT landscape and suggest possible solutions to improve generalizability of trial results, mitigate logistical pitfalls, and integrate real-world evidence into trials. Together, these strategies are designed to refine MM treatment guidelines and improve outcomes for all patient populations.

Addition of Elotuzumab to Backbone Treatment Regimens for Multiple Myeloma: An Updated Meta-Analysis of Randomized Clinical Trials

BACKGROUND

The efficacy of elotuzumab, an anti-SLAMF7 monoclonal antibody, in treating relapsed/refractory multiple myeloma (RRMM) and newly-diagnosed multiple myeloma (NDMM) has varied in randomized controlled trials (RCTs). Moreover, there is limited data on its real-world application.

PATIENTS AND METHODS

We conducted a systematic review and meta-analysis of RCTs investigating the addition of elotuzumab to backbone antimyeloma regimens. The primary outcome of interest was progression-free survival (PFS). Secondary efficacy outcomes included overall survival (OS), overall response rate (ORR), and rates of very good partial response or better (VGPR). Key toxicities were also evaluated.

RESULTS

Three RRMM trials (n = 915) and 5 NDMM trials (n = 1790) were included, with 50% of the 2705 patients receiving elotuzumab-containing triplets or quadruplets. In RRMM settings, elotuzumab use significantly improved PFS (hazard ratio [HR], 0.70; 95% confidence interval [CI], 0.60-0.82; P < .001; I² = 0%). This benefit was consistent among patients with high-risk cytogenetics (HR, 0.62; 95% CI, 0.43-0.90; P = .01; I² = 0%) and was particularly evident in those previously treated with proteasome inhibitors (PIs) or immunomodulatory drugs (IMiDs). The RRMM cohort also demonstrated better OS, ORR, and ≥VGPR rate. However, the NDMM cohort showed no significant improvements in any efficacy outcomes. Despite an increase in severe (grade ≥3) infections, elotuzumab use did not adversely affect rates of severe cytopenias, severe cardiac disorders, or second primary malignancies.

CONCLUSION

Our results suggest that elotuzumab-containing regimens represent valuable therapeutic options for PI/IMiD-exposed patients with RRMM. In contrast, elotuzumab's role in frontline settings remains limited.

Characteristics and outcomes of secondary acute lymphoblastic leukemia (sALL) after multiple myeloma (MM): SEER data analysis in a single-center institution

Background

Secondary acute lymphoblastic leukemia (sALL) is rare in patients diagnosed with antecedent multiple myeloma (MM). This study aimed to elucidate the clinical features and outcomes of patients with sALL after MM.

Methods

We conducted this population-based study using the Surveillance, Epidemiology, and End Results (SEER) database and retrospectively reviewed patients with sALL following MM treatment at our institution. Cox regression analysis was performed to investigate the prognostic factors for survival in patients with sALL.

Results

We identified 64,629 cases of MM (including 18 sALL from the SEER Plus 9 database, and three sALL from our institution). Younger patients with MM and those who received chemotherapy were at a higher risk of developing sALL. The novel agent era witnessed an increased incidence of sALL (post-novel agent era vs. pre-novel agent era: 0.31% [10/32,640] vs. 0.25% [8/31,989]) and shorter latency time (post-novel agent era vs. pre-novel agent era [median]: 51.5 vs. 74.5 months, P = 0.516), though the difference was not significant. The median age at sALL onset was 65 (range: 47-78) years. Significant cytopenia and absence of BCR/ABL fusion genes were common features in this patient population. The treatment of sALL is complicated by old age and poor performance status. The median survival of patients with sALL is 18 months, whereas those who received chemotherapy had significantly prolonged survival.

Conclusions

Patients with sALL combined with an antecedent MM, especially those with long-term exposure to immunomodulatory agents such as thalidomide or lenalidomide, should be cautiously evaluated and managed with a comprehensive approach.

Idecabtagene vicleucel or ciltacabtagene autoleucel for relapsed or refractory multiple myeloma: An international multicenter study

Idecabtagene vicleucel (ide-cel) and ciltacabtagene autoleucel (cilta-cel) have revolutionized the treatment of relapsed/refractory multiple myeloma (RRMM), but direct comparisons are lacking. Leveraging an international multicenter RRMM cohort, we compared the outcome of ide-cel (n = 162) versus cilta-cel (n = 42). Co-primary efficacy endpoints of the study were overall response rate (ORR) and progression-free survival (PFS). Co-primary safety endpoints were the incidence of cytokine release syndrome (CRS) and immune-effector cell-associated neurotoxicity syndrome (ICANS). Median turnaround time between apheresis and infusion was 47 days for ide-cel versus 68 days for cilta-cel (p < 0.001). Cilta-cel showed significantly higher ORR (93% vs. 79%; p < 0.001), with complete response at Day 30 of 48% versus 26% (p < 0.001). The 10-month PFS and overall survival (OS) was 82% and 90% for cilta-cel versus 47% and 77% ide-cel (p < 0.001 and p = 0.06), and improved outcome for cilta-cel was confirmed after multivariable adjustment. Incidence of CRS and ICANS appeared similar (81% and 19% for cilta-cel versus 85% and 19% for ide-cel), while 10% and 7% in the cilta-cel group versus 4% and 2% in the ide-cel group showed severe CRS and ICANS grade 3-4, with CRS occurring significantly earlier for ide-cel (median, 2 days vs. 4 days; p < 0.001). Nonrelapse mortality was 5% for cilta-cel versus 3% for ide-cel (p = 0.51). Cilta-cel showed later peak of CAR-T expansion at Day 14 versus Day 7 for ide-cel, while cilta-cel expansion was associated with ICANS. Our study provides real-world evidence that cilta-cel was associated with superior outcomes and distinct cellular dynamics versus ide-cel in triple-class exposed RRMM.

Real-World Outcomes of Upfront Autologous Hematopoietic Stem Cell Transplantation in Patients With Newly Diagnosed Multiple Myeloma With Deletion 17p

Despite tremendous advancements in multiple myeloma (MM) therapeutics, outcomes remain heterogeneous, heavily influenced by clinical and cytogenetic factors. Among these, deletion of the short arm of chromosome 17 (del(17p)) is a strong predictor of poor prognosis. The aim of this study was to evaluate real-world outcomes in patients with newly diagnosed MM (NDMM) with del(17p) undergoing upfront autologous hematopoietic stem cell transplantation (auto-HCT). We conducted a single-center retrospective analysis of patients with NDMM who underwent upfront auto-HCT at MD Anderson Cancer Center between 2008 and 2018. Primary endpoints were progression-free survival (PFS) and overall survival (OS), with secondary endpoints being hematological response and measurable residual disease (MRD) status postauto-HCT. MRD status in the bone marrow biopsy was evaluated using 8-color next-generation flow cytometry with a sensitivity of 1/10-5 cells. One hundred and fifteen patients were included (55% male). Median age at auto-HCT was 62 years (range 34 to 83). The median del(17p) clone size was 20%, with 51 (53%) patients having clone sizes >20% and 15 (15%) patients having clone sizes >55%. Additional high-risk cytogenetic abnormalities included t(4;14) in 15 (13%) patients, t(14;16) in 8 (7%) patients, and 1q21+ in 25 (22%) patients. After induction, 10% of patients achieved ≥ CR, and 50% achieved ≥ VGPR, with 25% having MRD-negative ≥ VGPR. Post-transplant, 42% achieved ≥ CR, and 83% achieved ≥ VGPR as best response, with 55% (48/87) having MRD-negative ≥ VGPR. With a median follow-up of 31.4 months (range 3.1 to 199.1), median PFS and OS for the entire cohort were 19.9 and 71.5 months, respectively, and 5-year OS was 53%. Concurrent del(17p) and t(4;14) were associated with significantly worse outcomes, with median PFS and OS of 11.5 and 22.4 months, respectively. In multivariable analysis (MVA), female sex was associated with worse PFS (HR [95% CI] 2.87 [1.75 to 4.72], P < .001), while MRD negative CR post-transplant (0.35 [0.18 to 0.68], P = .002) and maintenance therapy (0.46 [0.27 to 0.77], P = 0.003) were associated with better PFS. In MVA for OS, female sex (2.22 [1.18 to 4.17], P = 0.013) and the presence of t(4;14) (2.55 [1.09 to 5.95], P = 0.030) were associated with worse OS, whereas Karnofsky Performance Status of ≥90 (0.47 [0.23 to 0.94], P = 0.034) was associated with better OS. This study affirms del(17p) as a high-risk abnormality with unfavorable outcomes despite modern therapies. The co-occurrence of del(17p) and t(4;14) was associated with particularly poor outcomes. Novel approaches are needed for this high-risk subgroup.

Refining High-Risk Multiple Myeloma: Advancements in Genomic, Clinical, and Prognostic Criteria

Multiple myeloma (MM) is a heterogeneous disease, with MM patients experiencing different clinical outcomes depending on the disease's biological features. Novel insights into the molecular mechanisms of MM have led to the introduction of sophisticated drugs, which dramatically improved patient treatment and survival. To date, young patients with newly diagnosed MM could experience a median overall survival (OS) of 10 years. Nevertheless, a small proportion of patients still undergoes early disease progression and death. Indeed, cases defined as ultra-high-risk MM (uHRMM) and high-risk MM (HRMM) are destined for a worse outcome, with an OS of 2-3 and 3-5 years, respectively. In this regard, current risk stratification systems failed to identify this subset of patients better. The application of existing risk models has led to the identification of extremely heterogeneous categories of patients, and they have not taken into account biological and clinical differences. The concept of HRMM was initially formalised in 2015. Since then, a great effort has been made to identify those parameters whose presence pone MM patients at higher risk of developing an early relapse. The simultaneous presence of 2 or more unfavourable cytogenetic abnormalities, the identification of an extramedullary disease or the detection of circulating plasma cells, as well as high-risk gene expression profiling (GEP) signature, have shown to be well related to a worse outcome and are going to be incorporated into new prognostic systems. The introduction of the Individualised Risk Model for Multiple Myeloma (IRMMa) marks a significant advancement in the management of HRMM by integrating genomic and clinical data to tailor treatment strategies. This model demonstrates improved prognostic accuracy compared to traditional staging systems and emphasises the importance of personalised treatment approaches. The implementation of these advanced tools is essential for enhancing precision medicine in MM and improving outcomes for patients in high-risk categories.

Novel Drug Combinations and Donor Lymphocyte Infusions Allow Prolonged Disease Control in Multiple Myeloma Patients Relapsing after Allogeneic Transplantation

Although allogeneic stem cell transplantation (allo-SCT) is curative for only a minority of patients with multiple myeloma (MM), patients who relapse after allo-SCT can experience long-term survival, suggesting a synergy between antimyeloma drugs administered after allo-SCT and donor T cells. We retrospectively evaluated the outcome of MM patients reported to the Gruppo Italiano Trapianto Midollo Osseo e Terapia Cellulare (GITMO) network who underwent allo-SCT between 2009 and 2018, to identify predictors of long-term outcome in the whole population (242 patients) and predictors of prolonged overall survival (OS) after relapse in the subgroup of relapsed patients (118 patients). In the whole population, at a median follow-up of 40.9 months after allo-SCT, the median duration of OS and progression-free survival (PFS) were 39.4 and 19.0 months after allo-SCT, respectively. The cumulative incidence of nonrelapse mortality (NRM) was 10.3% at 1 year and 27.6% at 5 years. The cumulative incidence of grade II-IV acute graft-versus-host disease (GVHD) was 19.8%, and the 5-year cumulative incidence of moderate or severe chronic GVHD was 31.8%. In the multivariate model, older age at transplantation (P = .020), receipt of >2 lines of therapy before allo-SCT (P = .003), and transplantation from an unrelated or haploidentical donor (P = .025) were significant factors associated with reduced OS. Relapse after allo-SCT occurred in 118 patients (59%) at a median of 14.3 months (interquartile range, 7.2 to 26.9 months). Twenty patients (17%) received only steroids, radiotherapy, or supportive care; 41 (35%) received 1 line of salvage treatment; 23 (19%) received 2 lines of salvage treatment; and 34 (29%) received 3 or 4 lines of salvage treatment. Nine patients were treated exclusively with chemotherapy, 9 received at least 1 salvage treatment including immunomodulating agents, 43 patients were treated with at least 1 rescue therapy including proteasome inhibitors, and 37 patients received at least 1 salvage treatment including monoclonal antibodies (33 with daratumumab, 1 with elotuzumab, 1 with isatuximab, and 2 with belantamab). The median OS of relapsed patients was 38.5 months from allo-SCT and 20.2 months from relapse. In multivariate analysis, OS after relapse was significantly prolonged in patients with a longer time to relapse after allo-SCT (time to relapse 6 to 24 months, P = .016; time to relapse ≥24 months, P < .001) and in those who had received at least 3 lines of salvage treatment (P < .036) and donor lymphocyte infusion (DLI) (P = .020). In this study, patients who underwent transplantation in early phases of disease and with an HLA-identical sibling donor had the best chance of long-term survival. Late relapse after allo-SCT, multiple courses of salvage treatment, and an association with DLI could allow for long-term disease control in patients who experienced relapse after allo-SCT.

The correlation between serum bone metabolism indexes and bone disease and survival in newly diagnosed multiple myeloma patients

Objective Myeloma-related bone disease (MBD) is one of the most common complications of multiple myeloma (MM). This study aims to investigate the correlation between serum bone metabolism indexes (BMIs), the clinical characteristics and prognosis of newly diagnosed MM (NDMM) patients.

METHODS

The serum BMIs of 148 patients with NDMM in a single hematological disease treatment center from April 2014 to December 2019 were analyzed retrospectively, including type I collagen amino terminal elongation peptide (PINP), β-C-terminal telopeptide of type I collagen (β-CTX) and N-terminal osteocalcin (N-MID). Other clinical indexes were simultaneously collected and the degree of bone damage in patients was evaluated. We explored the effect of serum BMIs on the prognosis and identified independent prognostic factors. Another 77 NDMM patients from April 2018 to February 2021 served as the validation cohort.

RESULTS

The area under the curve (AUC) predicted by β-C-terminal telopeptide of type I collagen (β-CTX), type I collagen amino terminal elongation peptide (PINP), and N-terminal osteocalcin (N-MID) for overall survival (OS) were 0.708, 0.613, and 0.538, respectively. Patients with high serum levels had shorter OS (p < .001, p = .004, p = .027, respectively). Cox multivariate analysis indicated that serum β- CTX、lactic dehydrogenase、hemoglobin and the degree of bone injury were independent prognostic factors. A COX regression model was established with a C-index of 0.782 and validated with a C-index of 0.711.

CONCLUSION

The serum BMIs are correlated with the patients' OS, and β- CTX can be an independent prognostic factor.

Outcomes of Idecabtagene Vicleucel Therapy in Patients with Relapsed/Refractory Multiple Myeloma: A Single-Institution Experience

Background/Objectives: Idecabtagene vicleucel (ide-cel), an anti-B-cell maturation chimeric antigen receptor T-cell therapy, represents an unprecedented treatment option for relapsed/refractory multiple myeloma (R/R MM). Nevertheless, given its limitations, including the risk of adverse effects and unclear durability of efficacy, there remains a need to report the real-world clinical outcomes of ide-cel therapy in patients with R/R MM, as well as explore host predictive factors for therapy. Methods: We performed a single-center retrospective analysis of 25 adult patients with R/R MM who received ide-cel between 2021 and 2023 at the University of California San Diego Health. Data on baseline characteristics, efficacy, safety, and post-relapse outcomes were collected. Treatment responses were assessed using the International Myeloma Working Group criteria while survival analyses were conducted using the Kaplan-Meier and Cox proportional hazards methods. Results: The median age was 65. Twelve patients (48%) were male. Patients received a median of six lines of prior therapy with four patients (16%) receiving prior BCMA-targeted therapy. Six patients (24%) had high-risk cytogenetics while ten patients (40%) had extramedullary disease. The incidence of cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome incidence was 92% and 12%, respectively. All grade infection occurred in 11 patients (44%). Cytomegalovirus (CMV) reactivation occurred in 9 of 19 patients (47%) who were CMV IgG positive prior to CAR T-cell therapy. The objective response rate (ORR) was 84%; stringent complete response was seen in 14 patients (56%). After a median follow-up of 13 months, median progression-free survival (PFS) was 13.9 months (95% CI: 9.21 months-not reached [NR]); median overall survival (OS) was not reached (95% CI: 19.5 months-NR). Among the 11 patients (44%) who progressed after ide-cel therapy, median OS2 was 13.7 months; especially poor outcomes (median OS2 of 1.74 months) were observed in four patients who did not respond to ide-cel. Six of these eleven patients remained alive at time of data cutoff. Univariate and multivariate analysis revealed no significant predictors of ORR, PFS, or OS. Conclusions: Overall, ide-cel had comparable efficacy and safety to the KarMMa-1 trial and other reported real-world experiences.

The impact of high-risk cytogenetic abnormalities in extramedullary multiple myeloma in the era of novel agents: insights from a multicenter study

PURPOSE

This study aimed to examine the impact of high-risk cytogenetic abnormalities (HRA) on the survival outcomes of multiple myeloma patients with extramedullary disease (EMD) in the era of novel agents, utilizing the largest dataset of extramedullary multiple myeloma patients in China.

METHODS

This study included a total of 371 patients with EMD, comprising 113 patients with de novo EME and 258 patients with EMB.

RESULTS

Patients with one HRA and those with ≥ 2 HRA demonstrated significantly worse overall survival (OS) (P < 0.01) and progression-free survival (PFS) (P < 0.01) compared to patients without HRA. Additionally, 1q21 gain/amplification (1q21 +) remained a predictor of poor prognosis in EMD. CD38 monoclonal antibody-based therapy and single transplantation were less effective in improving survival outcomes for EMD with ≥ 2 HRA. Multivariable analysis identified LDH levels > 250 U/L, creatinine levels > 177 μmol/L, extramedullary extraosseous (EME), 1 HRA, and ≥ 2 HRA as independent adverse prognostic factors in patients with EMD.

CONCLUSION

Patients with EMD who had ≥ 2 HRA experienced an extremely poor prognosis, which could not be improved by single transplantation or CD38 monoclonal antibody-based treatment. The number of HRA could serve as an important factor in guiding treatment choices and predicting prognosis in patients with EMD. Furthermore, 1q21 + remained a significant factor associated with worse survival outcomes in EMD.

The significance of free light-chain ratio in light-chain monoclonal gammopathy of undetermined significance: a flow cytometry sub-study of the iStopMM screening study

Light-chain (LC) monoclonal gammopathy of undetermined significance (MGUS) is a precursor of multiple myeloma (MM) and related conditions. LC-MGUS is characterized by free light-chain (FLC) levels outside defined reference intervals, indirectly indicating underlying plasma cell (PC) monoclonality. Next-generation flow cytometry (NGF) was used to evaluate clonal PC presence in bone marrow (BM) samples from individuals with LC-MGUS in the iStopMM study, aiming to assess the predictive value of the FLC ratio for clonal PC presence and its prognostic implications. BM samples from 61 individuals with LC monoclonal gammopathy were analyzed. Clonal plasma cells were detected in 53.6% of LC-MGUS samples (n = 28) and in all samples from individuals with more advanced conditions (n = 33). The FLC ratio was predictive of clonal PC presence for kappa-involved FLC ratios (p < 0.05; n = 42), with an optimal cutoff of 3.15 (96.7% sensitivity, 91.7% specificity). Of 195 individuals with kappa-involved LC-MGUS in follow-up within the iStopMM study, none with FLC ratios >1.65 to 3.15 progressed to MM (n = 124), whereas 4/71 (5.6%) with FLC ratios >3.15 progressed over median follow-up of 55 months. These findings support using a kappa-involved FLC ratio cutoff of >3.15 to more accurately identify individuals at increased risk of developing symptomatic PC disorders.

Bortezomib-releasing silica-collagen xerogels for local treatment of osteolytic bone- and minimal residual disease in multiple myeloma

BACKGROUND

Accumulation of malignant plasma cells in the bone marrow causes lytic bone lesions in 80% of multiple myeloma patients. Frequently fracturing, they are challenging to treat surgically. Myeloma cells surviving treatment in the presumably protective environment of bone lesions impede their healing by continued impact on bone turnover and can explain regular progression of patients without detectable minimal residual disease (MRD). Locally applicable biomaterials could stabilize and foster healing of bone defects, simultaneously delivering anti-cancer compounds at systemically intolerable concentrations, overcoming drug resistance.

METHODS

We developed silica-collagen xerogels (sicXer) and bortezomib-releasing silica-collagen xerogels (boXer) for local treatment of osteolytic bone disease and MRD. In vitro and in vivo (tissue sections) release of bortezomib was assessed by ultrahigh-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Material impact on bone formation was assessed in vitro regarding osteoclast/osteoblast numbers and activity. In vivo, drilling defects in a rat- and the 5T33-myeloma mouse model were treated by both materials and assessed by immunohistochemistry, UPLC-MS/MS, µCT, and ToF-SIMS. The material's anti-myeloma activity was assessed using ten human myeloma cell lines (HMCLs) and eight primary myeloma cell samples including four patients refractory to systemic bortezomib treatment.

RESULTS

sicXer and boXer show primary stability comparable to trabecular bone. Granule size and preparation method tailor degradation as indicated by release of the xerogel components (silica and collagen) and bortezomib into culture medium. In vitro, both materials reduce osteoclast activity and do not negatively interfere with osteoblast differentiation and function. The presumed resulting net bone formation with maintained basic remodeling properties was validated in vivo in a rat bone defect model, showing significantly enhanced bone formation for boXer compared to non-treated defects. Both materials induce myeloma cell apoptosis in all HMCLs and primary myeloma cell samples. In the 5T33-myeloma mouse model, both materials stabilized drilling defects and locally controlled malignant plasma cell growth.

CONCLUSIONS

The combination of stabilization of fracture-prone lesions, stimulation of bone healing, and anti-tumor effect suggest clinical testing of sicXer and boXer as part of a combined systemic/local treatment strategy in multiple myeloma and non-malignant diseases.

Quadruplet regimens for patients with newly diagnosed multiple myeloma: a systematic review and meta-analysis

ABSTRACT

Quadruplet regimens (anti-CD38 monoclonal antibodies [mAbs] with proteasome inhibitor [PI] and immunomodulatory drugs [IMiDs]) are increasingly being investigated in newly diagnosed multiple myeloma (NDMM). The objective of our study was to conduct a systematic review and meta-analysis to measure the efficacy and toxicity of quadruplet regimens used in NDMM. Embase, MEDLINE, Web of Science, Cochrane Library, clinical trial registries, and meeting libraries from inception to 24 January 2024, in addition to American Society of Clinical Oncology conference abstracts 2024, were searched using terms reflecting multiple myeloma and components of the quadruplet regimen. Included studies were randomized controlled trials (RCTs) that compared backbone regimens consisting of a PI and IMiD vs the same regimen plus an anti-CD38 mAb in NDMM. We identified 7 RCTs including 3716 patients. Compared with triplets, quadruplets increase the overall response rate (ORR; relative risk [RR], 1.03; 95% confidence interval [CI], 1.01-1.05) and progression-free survival (PFS; hazard ratio [HR], 0.55; 95% CI, 0.46-0.66). Quadruplets increase the rates of minimal residual disease (MRD) negativity at 10-5 (RR, 1.39; 95% CI, 1.23-1.58) and 10-6 (RR, 1.62; 95% CI, 1.36-1.94). Quadruplets improve overall survival (OS; HR, 0.65; 95% CI, 0.53-0.79). There was a slight increase in the rates of grade 3 to 4 infections (RR, 1.22; 95% CI, 1.07-1.39) noted with quadruplets compared with triplets. Overall, in this meta-analysis, quadruplets were associated with improved efficacy including ORR, MRD negativity, PFS, and OS, with a slight increase in infection rates. Quadruplet regimens represent a new standard of care, particularly in transplant-eligible NDMM.

Patient-reported outcome domains in multiple myeloma randomized controlled trials and association with survival outcomes

Patient-reported outcomes (PROs) are crucial endpoints in multiple myeloma (MM) randomized controlled trials (RCTs), yet there is significant variability in their methodology and reporting. Our study aimed to (a) identify the most commonly pre-specified PRO domains in MM RCTs and those most responsive to modern therapies, and (b) examine the association between PROs and progression-free survival (PFS)/overall survival (OS). We performed a systematic review of MM RCTs that used EORTC QLQ-C30 and published between 01/2014-06/2023. The association between PFS/OS and PRO was explored using Fisher's exact test or Pearson's Chi-squared test. Thirty-five RCTs were identified, with PROs as secondary or exploratory endpoints in all studies. About one-third of RCTs (n=11, 31.4%) pre-specified at least one EORTC QLQ-C30 domain, with the most common domains being Global health status/Quality of life (GHS/QoL) (n = 10, 90.9%), Physical Functioning (n = 6, 54.5%), Fatigue (n = 6, 54.5%), and Pain (n = 6, 54.5%). A statistically significant and/or clinically meaningful difference in at least one EORTC QLQ-C30 domain between arms was seen in 23/35 trials (65.7%), with the most common domains showing improvement being GHS/QoL (12/23 trials), Pain (11/23 trials), Fatigue (9/23 trials), and Physical Functioning (9/23 trials). PRO was noted to be concordant with PFS in 19/33 (57.6%) trials (p = 0.398), and with OS in 22/31 (71%) trials (p = 0.018). Our study identified key PRO domains that can be potentially used as primary endpoint in MM RCTs. Additionally, significant association between PROs and OS highlight the importance of integrating PROs to better capture treatment efficacy.

Ide-cel vs standard regimens in triple-class-exposed relapsed and refractory multiple myeloma: updated KarMMa-3 analyses

ABSTRACT

Outcomes are poor in triple-class-exposed (TCE) relapsed and refractory multiple myeloma (R/RMM). In the phase 3 KarMMa-3 trial, patients with TCE R/RMM and 2 to 4 prior regimens were randomized 2:1 to idecabtagene vicleucel (ide-cel) or standard regimens (SRs). An interim analysis (IA) demonstrated significantly longer median progression-free survival (PFS; primary end point; 13.3 vs 4.4 months; P < .0001) and higher overall response rate (ORR) with ide-cel vs SRs. At final PFS analysis (median follow-up, 30.9 months), ide-cel further improved median PFS vs SRs (13.8 vs 4.4 months; hazard ratio [HR], 0.49; 95% confidence interval [CI], 0.38-0.63). PFS benefit with ide-cel vs SRs was observed regardless of number of prior lines of therapy, with greatest benefit after 2 prior lines (16.2 vs 4.8 months, respectively). ORR benefit was maintained with ide-cel vs SRs (71% vs 42%; complete response, 44% vs 5%). Patient-centric design allowed crossover from SRs (56%) to ide-cel upon progressive disease, confounding overall survival (OS) interpretation. At IA of OS, median was 41.4 (95% CI, 30.9 to not reached [NR]) vs 37.9 (95% CI, 23.4 to NR) months with ide-cel and SRs, respectively (HR, 1.01; 95% CI, 0.73-1.40); median OS in both arms was longer than historical data (9-22 months). Two prespecified analyses adjusting for crossover showed OS favoring ide-cel. This trial highlighted the importance of individualized bridging therapy to ensure adequate disease control during ide-cel manufacturing. Ide-cel improved patient-reported outcomes vs SRs. No new safety signals were reported. These results demonstrate the continued favorable benefit-risk profile of ide-cel in early-line and TCE R/RMM. This trial was registered at www.ClinicalTrials.gov as #NCT03651128.

Bispecific antibodies targeting BCMA or GPRC5D are highly effective in relapsed myeloma after CAR T-cell therapy

Despite the astonishing outcomes after chimeric antigen receptor (CAR) T-cell therapy for relapsed refractory multiple myeloma (RRMM), most patients eventually relapse. There are only limited data available on salvage therapies following relapse after BCMA-directed CAR T-cell therapy. Here, we analyzed outcomes of post-CAR T-cell therapy relapse and impact of different salvage strategies in an international cohort of 139 patients (n = 130 ide-cel, n = 9 cilta-cel), receiving talquetamab (n = 28), teclistamab (n = 37), combinations of immunomodulating drugs (IMiDs), proteasome inhibitors (PIs) or CD38 monoclonal antibodies (n = 43), and others (n = 31). The median time to relapse after CAR T-cell therapy was 5 months, 53% had the extramedullary disease (EMD) at relapse, associated with dismal post-relapse outcome (P = 0.005). Overall response and complete response upon salvage therapies were 79% and 39% for talquetamab, 64% and 32% for teclistamab, 30% and 0% for IMiDs/PIs/CD38, and 26% and 3% for others (P < 0.001). Duration of response, as well as median survival, was significantly improved with bispecific antibodies (P < 0.001, respectively). Bispecific antibodies seemed to overcome the poor prognosis associated with early relapse and EMD, and were independent predictors for improved survival in multivariable analysis. In summary, these results suggest bispecific antibodies as the standard of care for relapse after CAR T-cell therapy for RRMM.

Measurable residual disease by mass spectrometry and next-generation flow to assess treatment response in myeloma

ABSTRACT

Quantitative immunoprecipitation mass spectrometry (QIP-MS) allows the identification of the M-protein in patients with multiple myeloma (MM) otherwise in complete response, and could be considered suitable for measurable residual disease (MRD) evaluation in peripheral blood. In the context of the GEM2012MENOS65 and GEM2014MAIN trials, we compared the performance of QIP-MS in serum with next-generation flow (NGF) cytometry in bone marrow to assess MRD in paired samples obtained postinduction, transplant, consolidation and after 24 cycles of maintenance. At each time point, both NGF and QIP-MS were able to segregate 2 groups of patients with significantly different progression-free survival; when the evolution of the results obtained with either method was considered, maintaining or converting to MRD negativity was associated with longer survival, significantly better when compared with sustaining or converting to MRD positivity. Reemergence of MRD by QIP-MS was associated with high risk of imminent clinical progression. In conclusion, MRD evaluation by NGF and MS achieves similar prognostic value based in single time point assessments and kinetics. Thus, the minimally invasive nature of MRD monitoring by MS represents a breakthrough in highly sensitive response assessment in MM. The trials were registered at www.clinicaltrials.gov as #NCT01916252 (GEM2012MENOS65) and at EudraCT as #2012-005683-10; and as #NCT02406144 (GEM2014MAIN) and at EudraCT as 2014-00055410.

CAR T-cell therapy to treat multiple myeloma: current state and future directions

Chimeric antigen receptor (CAR) T-cell therapy represents a transformative advancement in treating relapsed or refractory multiple myeloma (MM) in both early- and late-line settings. MM, a plasma cell malignancy, traditionally requires ongoing complex drug regimens, posing significant burdens on patients. In contrast, CAR T-cell therapy offers a one-time treatment option without the need for continuous maintenance therapy. CAR T-cell therapy leverages engineered T-cells to target specific antigens on tumor cells, leading to their elimination. Current approved therapies target B-cell maturation antigen (BCMA); new targets are under investigation, such as G-protein-coupled receptor class C group 5 member D (GPRC5D). Despite its efficacy, CAR T-cell therapy is associated with serious toxicities such as cytokine release syndrome (CRS) and immune-effector cell-associated neurotoxicity syndrome (ICANS), necessitating careful management. The review will provide an overview of the design and manufacturing of CAR T-cells and current FDA indications, as well as challenges and future directions of CAR-T therapy for MM treatment.

Safety and efficacy of B cell maturation antigen-directed CAR T-cell therapy in patients with relapsed/refractory multiple myeloma and concurrent light chain amyloidosis

Clinical trials evaluating chimeric antigen receptor (CAR) T-cell therapy in relapsed/refractory multiple myeloma (RRMM) have typically excluded patients with AL amyloidosis. As a result, there are limited data on the safety and efficacy of CAR T-cell therapy in this patient population. We retrospectively reviewed eight consecutive patients with RRMM and AL amyloidosis who were treated with standard of care CAR T-cell therapy. Cytokine release syndrome was seen in 75% of patients (grade ≥3: 0%) and immune effector cell-associated neurotoxicity syndrome (grade 1) in only one patient. Low-grade cytopenias were common (any grade/grade ≥3: neutropenia 62.5%/37.5%, anemia 37.5%/0%, thrombocytopenia 25%/0%). CAR T-cell therapy led to rapid and deep responses with a median time to best response of 43 days and a hematologic very good partial response or better rate of 62.5%. Overall, we found that commercial CAR T-cell therapy was feasible, and effective in patients with RRMM and concurrent AL amyloidosis.

Isatuximab-dexamethasone-pomalidomide combination effects on serum M protein and PFS in myeloma: Development of a joint model using phase I/II data

This study aimed at leveraging data from phase I/II clinical trials to build a nonlinear joint model of serum M-protein kinetics and progression-free survival (PFS) accounting for the effects of isatuximab (Isa), pomalidomide (Pom), and dexamethasone (Dex) in patients with relapsed and/or refractory multiple myeloma. Serum M-protein levels and PFS data from 203 evaluable patients, included either in a phase I/II study (n = 173) or in a phase I study (n = 30), were used to build the model. First, we independently developed a longitudinal model and a PFS model. Then, we linked them in a nonlinear joint model by selecting the link function that best captured the association between serum M-protein kinetics and PFS. A Claret tumor growth-inhibition model accounting for the additive effects of Isa, with an Emax function, Pom, and Dex on serum M-protein elimination was selected to describe serum M-protein kinetics. PFS was best described with a log-logistic model and associations with baseline beta-2 microglobulin level, age, and coadministration of Dex were identified. The instantaneous change in serum M-protein level was found to be associated with PFS in the final joint model. Using model simulations, we retrospectively supported the Isa 10 mg/kg weekly for 4 weeks, then biweekly (QW/Q2W) dosing regimen of the ICARIA-MM phase III pivotal study, and validated it using the same phase III pivotal study data.

EANM guidelines on the use of [18F]FDG PET/CT in diagnosis, staging, prognostication, therapy assessment, and restaging of plasma cell disorders

We provide updated guidance and standards for the indication, acquisition, and interpretation of [18F]FDG PET/CT for plasma cell disorders. Procedures and characteristics are reported and different scenarios for the clinical use of [18F]FDG PET/CT are discussed. This document provides clinicians and technicians with the best available evidence to support the implementation of [18F]FDG PET/CT imaging in routine practice and future research.

Post-ASCT consolidation with elotuzumab, lenalidomide, and dexamethasone or elotuzumab, pomalidomide, and dexamethasone in high-risk and ultra-high-risk multiple myeloma: a retrospective single-center study

Patients with high-risk multiple-myeloma (HRMM) and ultra-high-risk multiple-myeloma (UHRMM) show rapid disease progression and shorter survival compared to those with standard-risk multiple-myeloma (SRMM). Lenalidomide maintenance after autologous stem cell transplant (ASCT) has shown inferior outcomes in this subgroup compared to SRMM, and there is an unmet need for improved post-ASCT therapy. This retrospective study, from September 2016 to March 2023, assesses elotuzumab combined with lenalidomide or pomalidomide and dexamethasone (ERd or EPd) as consolidation therapy post-ASCT for HRMM and UHRMM patients. HRMM (1 cytogenetic abnormality) and UHRMM (≥2 cytogenetic abnormalities) were defined using IMWG and mSMART criteria. Among 75 patients (median age: 64 years), 59 received ERd and 16 EPd. Median progression-free survival was 29.3 months for all patients, 32.7 months for HRMM, and 21.9 months for UHRMM. Elotuzumab plus an IMiD consolidation therapy post-ASCT demonstrated promising efficacy compared to other studies, with a fixed duration and reduced lenalidomide-related toxicity.

Phase II Study of Defactinib (VS6063) in Patients With Tumors With NF2 Loss: Results From the NCI-MATCH ECOG-ACRIN Trial (EAY131) Subprotocol U

PURPOSE

The NCI-MATCH trial assigned patients with solid tumors, lymphomas, or multiple myeloma to targeted therapies on the basis of identified genetic alterations from tumor biopsies. In preclinical models, neurofibromatosis 2 (NF2)-inactivated tumors display sensitivity to focal adhesion kinase (FAK) inhibition. The EAY131-U subprotocol evaluated the efficacy of defactinib, a FAK inhibitor, in patients with NF2-altered tumors.

METHODS

Patients whose tumors harbored an inactivating NF2 mutation on next-generation sequencing were assigned to subprotocol U. Defactinib 400 mg was given orally twice a day until progression or intolerable toxicity. The primary end point was objective response rate (ORR), secondary end points included toxicity, progression-free survival (PFS), and 6-month PFS.

RESULTS

Of 5,548 patients with sufficient tissue for genomic analysis, 57 patients were found to have NF2 alterations. Thirty-five patients ultimately enrolled and 33 were treated, with one not having central confirmation and two ineligible for outcome analysis. All patients had received previous treatment, with 52% having received three or more previous lines of therapy. The most common treatment-related toxicities were fatigue (36%), nausea (33%), and hyperbilirubinemia (27%), with 27% of patients having grade 3 toxicities. Median follow-up was 35.9 months with an ORR of 3% from one partial response in a patient with choroid meningioma. Among the 12 patients (40%) with a best response of stable disease, eight demonstrated some tumor shrinkage. Median PFS was 1.9 months, and six patients achieved a PFS >5.5 months. No correlation was identified between clinical outcomes and tumor histology or specific NF2 genotype.

CONCLUSION

This protocol did not meet its prespecified primary end point. Defactinib monotherapy had limited clinical activity in this cohort of previously treated patients with solid tumors exhibiting NF2 loss.

Phase 1 first-in-human study of MEDI2228, a BCMA-targeted ADC, in patients with relapsed refractory multiple myeloma

MEDI2228 is an antibody drug conjugate (ADC) comprised of a fully human B-cell maturation antigen (BCMA) antibody conjugated to a pyrrolobenzodiazepine (PBD) dimer. This phase 1 trial evaluated MEDI2228 in patients with relapsed/refractory (R/R) multiple myeloma (MM), who received prior treatment with approved agents from 3 classes of antimyeloma drugs (proteasome inhibitors, immunomodulatory drugs, and monoclonal antibodies). Primary endpoint was safety and tolerability; secondary endpoints included efficacy, pharmacokinetics, and immunogenicity. A total of 107 patients were treated and the maximum tolerated dose (MTD) was 0.14 mg/kg Q3W. Two patients had dose-limiting toxicities (DLTs; thrombocytopenia; 0.20 mg/kg Q3W). The most frequent treatment-related adverse events were photophobia (43.9%), rash (29.0%), and thrombocytopenia (19.6%). In MTD cohort A (n = 41), the objective response rate (ORR) was 56.1%, with 1 stringent complete response, 9 very good partial responses, and 13 partial responses. ORR was 53.3% in triple refractory patients. In cohort B (n=25), ORR was 32%. Although MEDI2228 demonstrated efficacy in R/R MM, ocular toxicity precluded further development of this drug.

Circular RNA_0003489 reflects unfavorable treatment response and shortened survival in newly diagnosed multiple myeloma patients who receive bortezomib-based induction therapy

OBJECTIVES

Circular RNA_0003489 (Circ_0003489) promotes multiple myeloma (MM) progression and bortezomib resistance in MM cells, while its potential as a biomarker in newly diagnosed MM (NDMM) patients is unclear. Thus, this study aimed to investigate the association of circ_0003489 expression with treatment response and survival in NDMM patients who received bortezomib-based induction therapy.

METHODS

Bone marrow (BM) specimens from 85 NDMM patients at diagnosis or before treatment and from 15 donor controls during BM examination were retrieved in this retrospective study. Circ_0003489 derived from BM plasma cells was detected by reverse transcription-quantitative polymerase chain reaction and cut by quartile and median for further analysis.

RESULTS

Circ_0003489 expression was increased in NDMM patients versus donor controls (P < 0.001). Circ_0003489 quartile was positively correlated with BM plasma cells (P = 0.040), international staging system (ISS) stage (P = 0.007), the revision of ISS stage (P = 0.003), beta-2-microglobulin (P = 0.011), and lactate dehydrogenase (P = 0.042) in NDMM patients. Increased circ_0003489 quartile was linked with a lower possibility of achieving complete response (P = 0.020) and partial response or better (P = 0.041) in NDMM patients. Elevated circ_0003489 expression cut by quartile (P = 0.020) and cut by median (P = 0.006) were linked with decreased progression-free survival (PFS) in NDMM patients. Increased circ_0003489 expression cut by median was associated with shortened overall survival (OS) in NDMM patients (P = 0.038). Meanwhile, higher circ_0003489 quartile independently forecasted poorer PFS (hazard ratio = 1.342, P = 0.045), but not OS in NDMM patients.

CONCLUSION

Circ_0003489 expression is increased and reflects unfavorable treatment response and survival in NDMM patients who receive bortezomib-based induction therapy.

Autologous stem cell transplantation in patients older than 65 years with multiple myeloma: a real-world study

INTRODUCTION

The treatment of elderly multiple myeloma (MM) patients with autologous stem cell transplantation (ASCT) is a controversial procedure. Most clinical trials evaluating the safety and efficacy of ASCT have primarily included patients younger than 65 years.

DESIGN AND METHODS

This was a retrospective analysis of patients with MM who underwent ASCT between 2008 and 2018. Patients at or over 65 years were compared with patients under 65 years. We analyzed treatment-related mortality (TRM), response rate, progression-free survival (PFS) and overall survival (OS).

RESULTS

Two hundred and twenty-one patients were included: 50 patients at or over 65 years, (median age 68 years), including 7 patients over 70 years and 151 patients under 65 years, (median age 57 years). No differences were found in the neutrophil and platelet engraftment, median days of hospitalization and life support requirement during the hospitalization period for the ASCT. No statistically significant differences were found in the incidence of TRM between both groups at 100 days post-transplant (2% vs. 2.9%, p = 0.322). The ASCT improved complete response and stringent complete response rates (44% vs. 37%, p < 0.001). Survival was not modified by age: after a median follow-up of 53 months, the estimated PFS rates at three years were 63% and 60% (p = 0.88) and the OS rates at five years were 75% and 74% (p = 0.72), respectively.

CONCLUSIONS

Our data suggest that the ASCT is feasible in selected elderly patients with MM over 65 years of age, achieving response and survival rates similar to those of younger patients.

Severe and continuous immunoparesis during induction or maintenance therapy in nontransplant patients with multiple myeloma is a sign of poor prognosis

OBJECTIVE

Multiple myeloma (MM) varies in clinical behavior, response to treatment and prognosis due to the heterogeneity of the disease. Data on the association between the immunoparesis status during treatment and prognosis in nontransplant MM patients are limited.

METHODS

In a retrospective analysis of 142 patients with MM, we examined the relationship between immunoparesis status and prognosis during treatment. All patients received novel agent-based therapy and did not undergo autologous stem cell transplantation. One, two, or three uninvolved immunoglobulins (Igs) below the lowest thresholds of normalcy were used to identify immunoparesis.

RESULTS

Patients with a greater degree of immunoparesis during treatment had shorter progression-free survival (PFS) and overall survival (OS). A total of 46.5% of the patients had severe and continuous immunoparesis (at least two uninvolved Igs suppressed continuously during treatment), representing a worse prognosis than those with complete or partial normalization of Igs during treatment. Among patients who achieved at least complete remission, PFS was poor in patients with severe and continuous immunoparesis. Furthermore, severe and continuous immunoparesis during treatment was a poor prognostic factor for PFS and OS according to multivariate analyses.

CONCLUSION

The degree of immunoparesis during treatment is a follow-up indicator for survival in nontransplant myeloma patients, and severe and continuous immunoparesis in nontransplant myeloma patients might be a sign of poor prognosis.

LocoMMotion: a study of real-life current standards of care in triple-class exposed patients with relapsed/refractory multiple myeloma - 2-year follow-up (final analysis)

Treatment of relapsed/refractory multiple myeloma (RRMM) is challenging as patients exhaust all available therapies and the disease becomes refractory to standard drug classes. Here we report the final results of LocoMMotion, the first prospective study of real-world clinical practice (RWCP) in triple-class exposed (TCE) patients with RRMM, with a median follow-up of 26.4 months (range, 0.1-35.0). Patients (N  =  248) had received median 4 prior LOT (range, 2-13) at enrollment. 91 unique regimens were used in index LOT. Overall response rate was 31.9% (95% CI, 26.1-38.0), median progression-free survival (PFS) was 4.6 months (95% CI, 3.9-5.6) and median overall survival was 13.8 months (95% CI, 10.8-17.0). 152 patients (61.3%) had subsequent LOTs with 134 unique regimens, of which 78 were used in first subsequent LOT. Median PFS2 (from start of study through first subsequent LOT) was 10.8 months (95% CI, 8.4-13.0). 158 patients died on study, 67.7% due to progressive disease. Additional subgroup analyses and long-term safety summaries are reported. The high number of RWCP treatment regimens utilized and poor clinical outcomes confirm a lack of standardized treatment for TCE patients with RRMM, highlighting the need for new treatments with novel mechanisms.

Efficacy of elotuzumab for multiple myeloma deteriorates after daratumumab: a multicenter retrospective study

Elotuzumab-based regimens are sometimes selected for multiple myeloma treatment after daratumumab-based regimens. However, there has been insufficient discussion on the efficacy of elotuzumab after daratumumab. We used Kansai Myeloma Forum registration data in a multicenter retrospective evaluation of the efficacy of elotuzumab after daratumumab. Overall survival (OS) rate and time to next treatment (TTNT) were significantly worse in the cohort given elotuzumab after daratumumab (Dara cohort, n = 47) than in the cohort with no history of daratumumab administration before elotuzumab (No-Dara cohort, n = 80, OS: P = 0.03; TTNT: P = 0.02; best response: P < 0.01). In the Dara cohort, OS and TTNT rates were worse with sequential elotuzumab use after daratumumab than with non-sequential (OS: P = 0.02; TTNT: P = 0.03). In patients given elotuzumab < 180 days after daratumumab, OS (P = 0.08) and best response (P = 0.21) tended to be worse, and TTNT was significantly worse (P = 0.01), than in those given elotuzumab after ≥ 180 days. These findings were confirmed by subgroup analyses and multivariate analyses. Monoclonal-antibody-free treatment might be preferable after daratumumab-based regimens. If possible, elotuzumab-based regimens should be considered only ≥ 180 days after daratumumab use.

Function of NLRP3 inflammasome activation in multiple myeloma

OBJECTIVE

The drug resistance of multiple myeloma (MM) cells is one of the main causes of relapse, refractory and progression of MM.

METHODS

First, Western blot analysis was used to detect the expression levels of NLRP3, ASC, pro-IL-1β and cleaved IL-1β, and RT-qPCR was used to detect the mRNA expression levels of them. The expression levels of IL-1β and IL-18 in the supernatant were detected by ELISA, and the expression levels of these factors in the activated group and the control group were compared to verify the activation of BMMCs and KM3.

RESULT

1. The protein expression of NLRP3 and cleavd-IL-1β in the BMMCs cells was significantly higher than that of the control group (P < 0.05). The mRNA expression levels of caspase-1 and IL-1β were higher than those of the control group (P = 0.03, P = 0.02). 2. The protein expression levels of NLRP3 and cleaved-IL-1β in the KM3 cells were significantly higher than those of the control group (P < 0.05). The expressions of caspase-1 mRNA(P = 0.016) and IL-1β mRNA(P = 0.037) were significantly increased compared with the control group. 3. The early apoptosis results of BMMCs showed that the apoptosis rate of the LPS+ATP+Dex group was lower than that of the Dex group (P = 0.017). The early apoptosis rate of the LPS+ATP+Dex+Vel group was decreased compared with the Dex+Vel group (P = 0.045). 4. The early apoptosis rate of KM3 in the LPS+ATP+Dex group was lower than that in the Dex group (P = 0.03).

CONCLUSION

1. LPS+ATP can activate NLRP3 inflammasome in multiple myeloma cells. 2. Activation of NLRP3 inflammasome inhibits the early apoptosis of myeloma cells induced by dexamethasone and bortezomib.

Phase II Study of Sunitinib in Tumors With c-KIT Mutations: Results From the NCI MATCH ECOG-ACRIN Trial (EAY131) Subprotocol V

PURPOSE

The NCI-MATCH study is a tumor-agnostic platform trial enrolling patients to targeted therapies on the basis of genomic alterations. Subprotocol V investigated sunitinib in patients with tumors harboring c-KIT mutations.

METHODS

EAY131-V, is an open-label, single-arm, phase II study. Eligible patients had malignancies containing somatic c-KIT mutation on exons 9, 11, 13, or 14. Exclusions were mutations on exons 17 and 18, gastrointestinal stromal tumors, renal cell carcinoma, and pancreatic neuroendocrine tumors. Patients received sunitinib 50 mg orally once daily for 4 weeks with 2-week rest per cycle, until disease progression or unacceptable toxicity. Primary end point was objective response rate (ORR); secondary end points were progression-free survival (PFS) at 6 months, PFS, overall survival, and toxicities.

RESULTS

Between November 1, 2016, and May 21, 2020, 10 patients were enrolled and nine were eligible and started treatment. The median age was 62 years (range, 30-76), 77.8% received two previous lines of systemic therapy, and 22.2% received >3 lines. The most common histology was melanoma (44%) and then squamous cell carcinoma of the lung or thymus (33%). There were two partial responses with an ORR of 22.2% (90% CI, 4.1 to 55) and stable disease in 44%. All patients demonstrated tumor shrinkage of target lesions. The estimated 6-month PFS was 33.3% (90% CI, 15.4 to 72.4). Grade 3-4 toxicities occurred in five patients (55.6%). This arm was closed in 2022 on the basis of low accrual. Prevalence of eligible c-KIT mutations after screening 5,540 patients was 0.45%.

CONCLUSION

Sunitinib for c-KIT mutations did not meet the primary end point, but in this small sample size, a potential signal cannot be ruled out. Rate of eligible c-KIT mutations was low, affecting accrual to this arm.

Multiple myeloma: clinical characteristics, current therapies and emerging innovative treatments targeting ribosome biogenesis dynamics

Multiple myeloma (MM) is a clinical disorder characterized by aberrant plasma cell growth in the bone marrow microenvironment. Globally, the prevalence of MM has been steadily increasing at an alarming rate. In the United States, more than 30,000 cases will be diagnosed in 2024 and it accounts for about 2% of cancer diagnoses and more than 2% of cancer deaths, more than double the worldwide figure. Both symptomatic and active MM are distinguished by uncontrolled plasma cell growth, which results in severe renal impairment, anemia, hypercalcemia, and bone loss. Multiple drugs have been approved by the FDA and are now widely used in clinical practice for MM. Although triplet and quadruplet induction regimens, autologous stem cell transplantation (ASCT), and maintenance treatment are used, MM continues to be an incurable illness characterized by relapses that may occur at various phases of its progression. MM patients with frailty, extramedullary disease, plasma cell leukemia, central nervous system recurrence, functional high risk, and the elderly are among those with the greatest current unmet needs. The high cost of care is an additional challenge. MM cells are highly protein secretary cells and thus are dependent on the activation of certain translation pathways. MM also has a high chance of altering ribosomal protein-encoding genes like MYC mutation. In this article we discuss the importance of ribosome biogenesis in promoting MM and RNA polymerase I inhibition as an upcoming treatment with potential promise for MM patients.

Anti-BCMA and GPRC5D bispecific antibodies in relapsed/refractory primary plasma cell leukemia: a case report

Plasma cell leukemia (PCL) is an aggressive and high-risk variant of multiple myeloma (MM) with a very poor prognosis. Given its rarity and aggressiveness, there is a lack of clinical trials testing the efficacity of novel therapies in these patients. New immune approaches such as B-cell maturation antigen (BCMA) and G protein-coupled receptor, family C, group 5, member D (GPRC5D) -targeting agents, including chimeric antigen receptor (CAR) T-cells and bispecific antibodies could play a role in PCL treatment. However, PCL patients were excluded from recent pivotal clinical trials testing those agents and only some case reports have been published. We present here the clinical course of a patient with relapsed/refractory (R/R) primary (p) PCL who was treated with anti-BCMA and anti-GPRC5D bispecific antibodies at our center.

BCMA CAR-T therapy combined with pomalidomide is a safe and effective treatment for relapsed/refractory multiple myeloma

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

An automated workflow based on data independent acquisition for practical and high-throughput personalized assay development and minimal residual disease monitoring in multiple myeloma patients

OBJECTIVES

Minimal residual disease (MRD) status in multiple myeloma (MM) is an important prognostic biomarker. Personalized blood-based targeted mass spectrometry detecting M-proteins (MS-MRD) was shown to provide a sensitive and minimally invasive alternative to MRD-assessment in bone marrow. However, MS-MRD still comprises of manual steps that hamper upscaling of MS-MRD testing. Here, we introduce a proof-of-concept for a novel workflow using data independent acquisition-parallel accumulation and serial fragmentation (dia-PASEF) and automated data processing.

METHODS

Using automated data processing of dia-PASEF measurements, we developed a workflow that identified unique targets from MM patient sera and personalized protein sequence databases. We generated patient-specific libraries linked to dia-PASEF methods and subsequently quantitated and reported M-protein concentrations in MM patient follow-up samples. Assay performance of parallel reaction monitoring (prm)-PASEF and dia-PASEF workflows were compared and we tested mixing patient intake sera for multiplexed target selection.

RESULTS

No significant differences were observed in lowest detectable concentration, linearity, and slope coefficient when comparing prm-PASEF and dia-PASEF measurements of serial dilutions of patient sera. To improve assay development times, we tested multiplexing patient intake sera for target selection which resulted in the selection of identical clonotypic peptides for both simplex and multiplex dia-PASEF. Furthermore, assay development times improved up to 25× when measuring multiplexed samples for peptide selection compared to simplex.

CONCLUSIONS

Dia-PASEF technology combined with automated data processing and multiplexed target selection facilitated the development of a faster MS-MRD workflow which benefits upscaling and is an important step towards the clinical implementation of MS-MRD.