Carfilzomib, lenalidomide, and dexamethasone or lenalidomide alone as maintenance therapy after autologous stem-cell transplantation in patients with multiple myeloma (ATLAS): interim analysis of a randomised, open-label, phase 3 trial

Current State of Evidence on Definitions and Management of High-Risk Multiple Myeloma

PURPOSE OF REVIEW

This review aims to address the subgroup of patients with newly diagnosed multiple myeloma (NDMM) who have high-risk multiple myeloma (HRMM) and continue to experience poor outcomes despite recent therapeutic advances. We will explore various clinical, biochemical, imaging, genetic, and dynamic features associated with high-risk status, along with the different risk stratification tools developed to identify HRMM patients.

RECENT FINDINGS

Although numerous parameters for defining HRMM have been proposed, a universally accepted definition remains absent. Studies have shown diverse treatment responses and varying outcomes in HRMM patients, prompting the development of tailored therapeutic approaches. Emerging evidence supports the need for refined definitions and more targeted strategies to improve HRMM management. HRMM patients represent an unmet need in NDMM treatment, and a standardized definition for HRMM is crucial for advancing research and clinical care. This review discusses current and future treatment options, the necessity for a consistent HRMM definition, and the importance of clinical trials focused on this high-risk group to bridge existing treatment gaps.

First Line Treatment of Newly Diagnosed Transplant Eligible Multiple Myeloma Recommendations From a Canadian Consensus Guideline Consortium

The availability of effective therapies for multiple myeloma (MM) has sparked debate on the role of first line autologous stem cell transplantation (ASCT), particularly in standard-risk patients. However, treatment for individuals with high-risk disease continues to display suboptimal outcomes. With novel therapies used earlier, practice is changing rapidly in the field of MM. Presently, quadruplet induction therapy incorporating an anti-CD38 monoclonal antibody to a proteasome inhibitor and an immunomodulatory drug prior to ASCT followed by maintenance therapy stands as the foremost strategy for attaining deep and sustained responses in transplant eligible MM (TEMM). This Canadian Consensus Guideline Consortium (CGC) proposes consensus recommendations for the first line treatment of TEMM. To address the needs of physicians and people diagnosed with MM, this document focuses on ASCT eligibility, induction therapy, mobilization and collection, conditioning, consolidation, and maintenance therapy, as well as, high-risk populations, management of adverse events, assessment of treatment response, and monitoring for disease relapse. The CGC will periodically review the recommendations herein and update as necessary.

Multiple Myeloma: Improved Outcomes Resulting from a Rapidly Expanding Number of Therapeutic Options

Multiple myeloma (MM) is a bone-marrow-based cancer of plasma cells. Over the last 2 decades, marked treatment advances have led to improvements in the overall survival (OS) of patients with this disease. Key developments include the use of chemotherapy, immunomodulatory drugs, proteasome inhibitors, and monoclonal antibodies. MM remains incurable, with outcomes influenced by many factors, including age, sex, genetics, and treatment response. This review summarizes recent studies regarding monitoring and treatment of MM, emphasizing the efficacy of new therapies, the impact of maintenance treatments, and approaches for managing relapsed or refractory MM. The role of specific drug classes used to treat MM, including immunomodulatory drugs, proteasome inhibitors, monoclonal antibodies, and newer treatments such as chimeric antigen receptor T-cell therapies and bispecific antibodies are discussed. Combination therapies have significantly improved outcomes. Maintenance therapies, particularly with lenalidomide, have been effective in extending OS but lead to an increased risk of secondary cancers. Venetoclax, selinexor, and ruxolitinib have shown potential as new therapeutic options for patients with relapsed or refractory MM. Immune-based treatments, such as chimeric antigen receptor T-cell therapy and bispecific antibodies, mark a major advancement for heavily pretreated patients, although challenges remain related to cost, availability, and side effects. The treatment landscape for patients with MM has seen significant progress, with current therapies providing a longer OS and better quality of life. Future research should focus on optimizing these strategies, personalizing therapies, and exploring new therapeutic targets.

Autologous stem-cell transplantation and maintenance therapy for transplant-eligible multiple myeloma patients: cost-effectiveness analysis based on a network meta-analysis

BACKGROUND

This study aimed to evaluate the cost-effectiveness of ASCT and maintenance therapy strategies for transplant-eligible patients with newly diagnosed multiple myeloma from a Chinese healthcare perspective.

RESEARCH DESIGN AND METHODS

A short-run decision tree and a long-run Markov model were created to assess the mean costs and quality-adjusted life-years (QALYs) of ASCT plus maintenance therapy over a lifetime horizon. Utility values were sourced from published literature, while healthcare costs were based on a single-center retrospective analysis and national drug bidding data.

RESULTS

The ASCT strategy with two-year daratumumab maintenance had the lowest discounted costs (1,394,183 CNY). Compared to no ASCT with continuous lenalidomide maintenance, ASCT had an ICER of 90,997 CNY/QALY. With one-year lenalidomide maintenance, ASCT provided more QALYs at lower costs. One-year lenalidomide maintenance after ASCT also resulted in higher QALYs and lower costs than no maintenance, while continuous lenalidomide had an ICER of 396,731 CNY/QALY.

CONCLUSIONS

Under the WTP threshold of CNY 268,074 per QALY, ASCT strategies were more cost-effective than non-ASCT approaches. One-year lenalidomide therapy after ASCT was more cost-effective than no maintenance or continuous therapy. Among all strategies, ASCT followed by two years of daratumumab maintenance was the most cost-effective option.

Real-world evidence of Carfilzomib, Lenalidomide and Dexamethasone (KRD) Scheme in patients with relapsed / refractory multiple myeloma

Carfilzomib, lenalidomide and dexamethasone (KRd) is still a widely used treatment option for patients with relapsed / refractory multiple myeloma (RRMM). However, there is limited real-world evidence. Here we evaluated the efficacy and safety of KRd in patients with RRMM treated following the standard clinical practice of the hospitals in the Catalan region. This was a retrospective, observational study. The objective response rate (ORR) according to IMWG criteria was the primary endpoint. Secondary endpoints included progression-free survival (PFS) and overall survival (OS). The study planned to include at least 100-150 patients. In total 194 patients were included. Median age was 64 years (range: 40-88) and 56% were male. All patients had received bortezomib. Additionally, 89 patients (46%) had received thalidomide and 29 (15%) lenalidomide. The ORR was 73% (95% CI: 66-79), with 72 patients (37%) having ≥ CR. The ORR was influenced by ISS score, number of previous treatments and exposure to lenalidomide. The median PFS was 26 months and 2-years OS rate 70%. The ISS stage and LDH levels were independent prognostic factors of survival. In conclusion, the KRd scheme led to a good effectiveness comparable safety profile to the phase III clinical trial in patients with RRMM.

Measurable Residual Disease in Hematological Cancers

Minimal residual disease (MRD) is most easily defined as a minimal amount of cancer cells that remain following the treatment of the disease, potentially owing to disease recurrence and the patient's dismal prognosis [...].

Discontinuation of maintenance therapy in multiple myeloma guided by multimodal measurable residual disease negativity (MRD2STOP)

MRD2STOP is a pragmatic trial evaluating maintenance therapy cessation guided by measurable residual disease (MRD) negativity in multiple myeloma (MM). Eligible patients had previous MRD < 10-5, received ≥1 year of maintenance, and were prospectively confirmed to have undetectable disease by positron emission tomography, bone marrow (BM) flow cytometry (limit of detection [LoD] 10-5), and BM clonoSEQ (LoD 10-6). BM aspirates enriched for CD138+ cells were analyzed by clonoSEQ to achieve MRD 10-7 sensitivity. We evaluated the incidence of disease resurgence and progression-free survival (PFS), stratified by 10-7 status. Forty-seven patients discontinued maintenance after a median of 36 months. Baseline MRD ≥ 10-7 was observed in 19% (9/47). The median follow-up post-discontinuation was 30 months. Disease resurgence (MRD 10 ≥ -6) occurred in 11 patients, including 5 disease progressions. One patient died from a second cancer. The estimated 3-year cumulative incidence of disease resurgence was 20% for patients with baseline MRD < 10-7 compared to 75% for MRD ≥ 10-7 (HR 7.8, 95% CI 2.2-27.6, p = 0.001). Baseline MRD ≥ 10-7 was associated with inferior PFS compared to MRD < 10-7 (HR 10.1, 95% CI 1.6-62.3; 3-year PFS 49% vs 92%). Maintenance discontinuation in patients with MM and MRD < 10-6 led to low rates of disease resurgence. MRD < 10-7 may be a superior cessation threshold, requiring further validation.

Intensive salvage chemotherapy with VDTPACE or mCBAD followed by hematopoietic stem-cell support for refractory/relapsed multiple myeloma

INTRODUCTION

Triple- and quad-refractory multiple myeloma patients usually have an aggressive course and a poor prognosis. Available therapeutic options are scarce.

METHODS

The objective of the current study was to evaluate responses and toxicities of VDTPACE or mCBAD with hematopoietic stem-cell support as a bridge to subsequent therapies in patients with refractory/relapsed multiple myeloma.

RESULTS

Thirteen patients were included (11 mCBAD, 2 VDTPACE), and 21 cycles of chemotherapy with hematopoietic stem-cell support were delivered. Mean number of previous therapies was 4.8. Stem cells were infused on a median day 9.9 after chemotherapy. Mean time to neutrophil recovery was 18.2 days in patients receiving the first cycle and 15.9 following subsequent cycles. Before therapy, most patients were in PD (77%), PR (15%), or VGPR (8%). Following treatment, the best responses achieved were PR (46%), VGPR (46%), and CR (8%). Median overall and progression-free survivals were 17 and 9 months. There has been no case of non-relapse mortality. In the 21 cycles, the main complications were infectious.

CONCLUSION

Intensive chemotherapy can decrease disease burden in patients with relapsed/refractory MM, and stem-cell support can successfully decrease toxicities and treatment-related mortality associated with these regimens and may be a good bridging option.

Measurable Residual Disease Testing in Multiple Myeloma Following T-Cell Redirecting Therapies

Several novel T-cell-based therapies have recently become available for multiple myeloma (MM). These T-cell redirecting therapies (TRTs) include chimeric antigen receptor T-cells (CAR-T) and bispecific antibodies (BiAbs). In both clinical trial and real-world data, these therapies have demonstrated high rates of deep clinical response, and some are now approved for second-line treatment for relapsed MM. The deep and sustained clinical responses these therapies are capable of inducing will require sophisticated response monitoring to provide meaningful information for patient care. Obtaining measurable residual disease (MRD) negativity has been validated as an independent positive prognostic marker for progression-free survival (PFS) and overall survival (OS) in both newly diagnosed and relapsed refractory patients with multiple myeloma. Assessment for MRD negativity was performed in all of the trials for FDA-approved TRT. Here, we summarize pertinent data for MRD assessment following TRT in MM and provide a rationale and structured framework for conducting MRD testing post TRT.

Mass spectrometry-based assessment of M protein in peripheral blood during maintenance therapy in multiple myeloma

ABSTRACT

Mass spectrometry (MS) can detect multiple myeloma-derived monoclonal proteins in the peripheral blood (PB) with high sensitivity, potentially serving as a PB assay for measurable residual disease (MRD). This study evaluated the significance of PB MS MRD negativity during posttransplant therapy in patients with newly diagnosed multiple myeloma. Serum samples from 138 patients treated in the phase 3 ATLAS trial of posttransplant maintenance with either carfilzomib, lenalidomide, and dexamethasone, or with lenalidomide alone were analyzed using EXENT MS methodology. We established feasibility of measuring MRD by MS in the PB in the posttransplant setting, despite unavailability of pretreatment calibration samples. There was high agreement between MRD by MS in the PB and paired bone marrow (BM) MRD results at the 10-5 threshold, assessed by either next-generation sequencing (NGS) or multiparameter flow cytometry (MFC) (70% and 67%, respectively). Agreement between PB MS and both BM MRD methods was lowest early after transplant and increased with time. MS negativity was associated with improved progression-free survival (PFS), which, in landmark analysis, reached statistical significance after 18 cycles after transplant. Combined PB/BM MRD negativity by MFC or NGS was associated with superior PFS compared with MRD negativity by only 1 modality. Sustained MS negativity carried similar prognostic performance to sustained BM MRD negativity at the 10-5 threshold. Overall, posttransplant MS assessment was feasible and provided additional prognostic information to BM MRD negativity. Further studies are needed to confirm the role and optimal timing of MS in disease evaluation algorithms. The ATLAS trial is registered at www.clinicaltrials.gov as #NCT02659293.

Maintenance therapy for cytogenetically high-risk multiple myeloma: landscape in the era of novel drugs

Although the significant strides in novel therapeutic approaches have prolonged the survival of multiple myeloma (MM) patients, the unfavorable prognosis of cytogenetically high-risk newly diagnosed MM (NDMM) remains intractable with the lack of consensus regarding the choice of maintenance regimens. Therefore, this study was initiated with the aim of examining the effectiveness of various maintenance treatments for this group of patients in jeopardy. Overall, 17 studies with 1937 high-risk NDMM patients were included in the network meta-analysis. Combination therapies involving novel drugs presented encouraging prospects in the maintenance phase, while the patients and circumstances for the application of different regimens still needed to be further distinguished and clarified. To investigate the current status of maintenance therapy of high-risk NDMM patients in clinical practice, a real-world cohort of high-risk NDMM was retrospectively incorporated 80 patients with lenalidomide maintenance and 53 patients with bortezomib maintenance, presenting the median PFS of 31.7 months and 30.4 months, respectively (p = 0.874, HR = 0.966, 95% CI: 0.628-1.486). Collectively, this study illuminated the present constraints of conventional approaches during the maintenance phase for high-risk NDMM patients while highlighting the future potential associated with enhanced regimens integrating novel medications.

Bortezomib, thalidomide, and dexamethasone with or without daratumumab and followed by daratumumab maintenance or observation in transplant-eligible newly diagnosed multiple myeloma: long-term follow-up of the CASSIOPEIA randomised controlled phase 3 trial

BACKGROUND

CASSIOPEIA part 1 demonstrated superior depth of response and prolonged progression-free survival with daratumumab in combination with bortezomib, thalidomide, and dexamethasone (D-VTd) versus bortezomib, thalidomide, and dexamethasone (VTd) alone as an induction and consolidation regimen in transplant-eligible patients newly diagnosed with myeloma. In CASSIOPEIA part 2, daratumumab maintenance significantly improved progression-free survival and increased minimal residual disease (MRD)-negativity rates versus observation. Here, we report long-term study outcomes of CASSIOPEIA.

METHODS

CASSIOPEIA was a two-part, open-label, phase 3 trial of patients done at 111 European academic and community-based centres. Eligible patients were aged 18-65 years with transplant-eligible newly diagnosed myeloma and an Eastern Cooperative Oncology Group performance status of 0-2. In part 1, patients were randomly assigned (1:1) to pre-transplant induction and post-transplant consolidation with D-VTd or VTd. Patients who completed consolidation and had a partial response or better were re-randomised (1:1) to intravenous daratumumab maintenance (16 mg/kg every 8 weeks) or observation for 2 years or less. An interactive web-based system was used for both randomisations, and randomisation was balanced using permuted blocks of four. Stratification factors for the first randomisation (induction and consolidation phase) were site affiliation, International Staging System disease stage, and cytogenetic risk status. Stratification factors for the second randomisation (maintenance phase) were induction treatment and depth of response in the induction and consolidation phase. The primary endpoint for the induction and consolidation phase was the proportion of patients who achieved a stringent complete response after consolidation; results for this endpoint remain unchanged from those reported previously. The primary endpoint for the maintenance phase was progression-free survival from second randomisation. Efficacy evaluations in the induction and consolidation phase were done on the intention-to-treat population, which included all patients who underwent first randomisation, and efficacy analyses in the maintenance phase were done in the maintenance-specific intention-to-treat population, which included all patients who were randomly assigned at the second randomisation. This analysis represents the final data cutoff at the end of the study. The trial is registered with ClinicalTrials.gov, NCT02541383.

FINDINGS

Between Sept 22, 2015 and Aug 1, 2017, 1085 patients were randomly assigned to D-VTd (n=543) or VTd (n=542); between May 30, 2016 and June 18, 2018, 886 were re-randomised to daratumumab maintenance (n=442) or observation (n=444). At the clinical cutoff date, Sept 1, 2023, median follow-up was 80·1 months (IQR 75·7-85·6) from first randomisation and 70·6 months (66·4-76·1) from second randomisation. Progression-free survival from second randomisation was significantly longer in the daratumumab maintenance group than the observation-alone group (median not reached [95% CI 79·9-not estimable (NE)] vs 45·8 months [41·8-49·6]; HR 0·49 [95% CI 0·40-0·59]; p<0·0001); benefit was observed with D-VTd with daratumumab maintenance versus D-VTd with observation (median not reached [74·6-NE] vs 72·1 months [52·8-NE]; 0·76 [0·58-1·00]; p=0·048) and VTd with daratumumab maintenance versus VTd with observation (median not reached [66·9-NE] vs 32·7 months [27·2-38·7]; 0·34 [0·26-0·44]; p<0·0001).

INTERPRETATION

The long-term follow-up results of CASSIOPEIA show that including daratumumab in both the induction and consolidation phase and the maintenance phase led to superior progression-free survival outcomes. Our results confirm D-VTd induction and consolidation as a standard of care, and support the option of subsequent daratumumab monotherapy maintenance, for transplant-eligible patients with newly diagnosed multiple myeloma.

FUNDING

Intergroupe Francophone du Myélome, Dutch-Belgian Cooperative Trial Group for Hematology Oncology, and Janssen Research & Development.

Targeting Ikaros and Aiolos: reviewing novel protein degraders for the treatment of multiple myeloma, with a focus on iberdomide and mezigdomide

INTRODUCTION

The treatment of multiple myeloma (MM) is evolving rapidly. Quadruplet regimens incorporating proteasome inhibitors, immunomodulatory drugs (IMiDs), and CD38 monoclonal antibodies have emerged as standard-of-care options for newly diagnosed MM, and numerous novel therapies have been approved for relapsed/refractory MM. However, there remains a need for novel options in multiple settings, including refractoriness to frontline standards of care.

AREAS COVERED

Targeting degradation of IKZF1 and IKZF3 - Ikaros and Aiolos - through modulation of cereblon, an E3 ligase substrate recruiter/receptor, is a key mechanism of action of the IMiDs and the CELMoD agents. Two CELMoD agents, iberdomide and mezigdomide, have demonstrated substantial preclinical and clinical activity in MM and have entered phase 3 investigation. Using a literature search methodology comprising searches of PubMed (unlimited time-frame) and international hematology/oncology conference abstracts (2019-2023), this paper reviews the importance of Ikaros and Aiolos in MM, the mechanism of action of the IMiDs and CELMoD agents and their relative potency for targeting Ikaros and Aiolos, and preclinical and clinical data on iberdomide and mezigdomide.

EXPERT OPINION

Emerging data suggest that iberdomide and mezigdomide have promising activity, including in IMiD-resistant settings and, pending phase 3 findings, may provide additional treatment options for patients with MM.

Multiple myeloma: signaling pathways and targeted therapy

Multiple myeloma (MM) is the second most common hematological malignancy of plasma cells, characterized by osteolytic bone lesions, anemia, hypercalcemia, renal failure, and the accumulation of malignant plasma cells. The pathogenesis of MM involves the interaction between MM cells and the bone marrow microenvironment through soluble cytokines and cell adhesion molecules, which activate various signaling pathways such as PI3K/AKT/mTOR, RAS/MAPK, JAK/STAT, Wnt/β-catenin, and NF-κB pathways. Aberrant activation of these pathways contributes to the proliferation, survival, migration, and drug resistance of myeloma cells, making them attractive targets for therapeutic intervention. Currently, approved drugs targeting these signaling pathways in MM are limited, with many inhibitors and inducers still in preclinical or clinical research stages. Therapeutic options for MM include non-targeted drugs like alkylating agents, corticosteroids, immunomodulatory drugs, proteasome inhibitors, and histone deacetylase inhibitors. Additionally, targeted drugs such as monoclonal antibodies, chimeric antigen receptor T cells, bispecific T-cell engagers, and bispecific antibodies are being used in MM treatment. Despite significant advancements in MM treatment, the disease remains incurable, emphasizing the need for the development of novel or combined targeted therapies based on emerging theoretical knowledge, technologies, and platforms. In this review, we highlight the key role of signaling pathways in the malignant progression and treatment of MM, exploring advances in targeted therapy and potential treatments to offer further insights for improving MM management and outcomes.

Minimal Residual Disease-Adapted Therapy in Multiple Myeloma: Current Evidence and Opinions

PURPOSE OF REVIEW

Multiple myeloma (MM) is a biologically heterogeneous malignancy with relatively uniform treatment paradigms. This review aims to assess the growing role of Minimal Residual Disease (MRD) assessment in facilitating response-adapted therapeutic decision making to individualize therapy in MM.

RECENT FINDINGS

MRD has been repeatedly demonstrated to provide strong prognostic information, superseding traditional IMWG response criteria. The use of MRD to modulate therapy remains controversial. Here, we review the existing landscape of MRD-adapted trial designs in both induction/consolidation and maintenance settings, including recent data from influential studies and retrospective analyses. We navigate existing data, leverage the increased resolution of longitudinal MRD assessments, and comment on trials in progress to explain our current utilization of MRD in the clinic. MRD transcends traditional response assessments by providing a window into disease-treatment interaction over time. As a strong patient-level surrogate, MRD has limited current use in individualizing treatment, but is poised to comprehensively shape treatment strategies at many key points in a patient's MM course.

Navigating High-Risk and Ultrahigh-Risk Multiple Myeloma: Challenges and Emerging Strategies

Despite significant improvement in the outcomes of patients with newly diagnosed multiple myeloma (NDMM) with novel therapies, there is still an underserved high-risk (HR) population that experiences early disease progression and death. With the median survival crossing 10 years, we defined ultrahigh-risk (uHR)MM as MM leading to death within 24-36 months of diagnosis and HRMM as MM leading to death within 36-60 months. Several features have emerged as markers of uHRMM: the co-occurrence of two or more high-risk cytogenetic abnormalities, extramedullary disease, plasma cell leukemia and a high-risk gene expression profiling signature. The heterogeneous risk definition across trials, the few trials available designed for HR patients, and the small HR subgroups in all-comers trials make it difficult to generate recommendations with high levels of evidence. Nevertheless, regardless of treatment administered, several studies consistently showed that achieving and maintaining measurable residual disease negativity is now considered the main factor able to mitigate the adverse prognosis related to baseline features. For fit patients with HR transplant-eligible (TE) NDMM, quadruplet induction/consolidation treatment with anti-CD38 monoclonal antibodies, immunomodulatory agents, proteasome inhibitors and dexamethasone, and autologous stem-cell transplant and maintenance with, if available, at least a doublet combination could be considered the option of choice. For non-TE NDMM, considering the recent data generated and carefully reviewing those upcoming, quadruplet treatment consisting of anti-CD38 monoclonal antibodies, immunomodulatory agents, proteasome inhibitors, and dexamethasone should also be considered. Future trials integrating BCMA-directed novel generation immunotherapies hold great potential for further advancing the treatment landscape in all NDMM patients with HR disease.

QoL during KTd or KRd induction followed by K maintenance or observation in transplant noneligible patients with newly diagnosed multiple myeloma: Longitudinal and cross-sectional analysis of the randomized AGMT 02 study

Understanding the impact of induction and maintenance therapy on patients' quality of life (QoL) is important for treatment selection. This study aims to compare patient-reported QoL between patients treated with KTd or KRd induction therapy and K maintenance therapy or observation. QoL was assessed using the EORTC QOL-C 30 and QOL-MY20 questionnaires in the AGMT-02 study, in which 123 patients with newly diagnosed transplant ineligible multiple myeloma were randomized to nine cycles of either KTd or KRd induction therapy, followed by 12 cycles of K maintenance therapy, or observation. Longitudinal assessments showed statistically significant improvements in global health-related QoL, various disease symptoms and pain for both treatment regimens. KTd improved insomnia and fatigue, and KRd improved physical functioning. Cross-sectional comparisons indicated a "slight" superiority of KTd over KRd in several scales, with the exception of higher neuropathy scores with KTd. During maintenance, longitudinal comparisons showed no statistically significant changes. Cross-sectional comparisons revealed a "slight" improvement in cognitive functioning during carfilzomib therapy, but a worsening in most other QoL scales. Induction therapy led to improvements in most QoL items, while maintenance therapy with K maintenance was associated with "slight" or "moderate" impairments in several QoL scales compared with the observation group.

Historical Perspective of High-Dose Therapy Followed by Autologous Stem Cell Transplantation in Multiple Myeloma

BACKGROUND

High-dose therapy (HDT) followed by autologous stem cell transplantation (ASCT) has become part of standard of care (SOC) in newly diagnosed multiple myeloma. In this review, we provide a historical perspective on ASCT since its introduction in the 1990s.

SUMMARY

Overall survival (OS) benefit for HDT followed by ASCT was demonstrated in studies comparing HDT with ASCT to standard-dose therapy (SDT) before the era of novel agents. Conditioning is done with melphalan 200 mg/m2. Lower doses (MEL140, MEL150) for older patients with comorbidities are safe and have comparable results. The addition of busulfan to melphalan improves progression-free survival (PFS) but not OS. HDT with ASCT after induction with novel agents prolongs PFS but not OS compared to SDT alone. The benefit is more evident in patients with high-risk cytogenetics. Mobilization can be achieved with granulocyte colony-stimulating factor alone, but is improved with the addition of chemotherapy. Plerixafor reduces mobilization failure and enables sufficient stem cell collection after induction with novel agents. ASCT is safe with a low rate of mortality (1%), and selected patients can be managed as outpatients.

KEY MESSAGES

HDT followed by ASCT remains part of SOC due to its PFS benefit and relatively low toxicity.

Randomized comparison between KTd and KRd induction therapy followed by maintenance therapy with K or observation in transplant-ineligible patients with newly diagnosed multiple myeloma

Randomized comparison between KTd and KRd induction followed by second randomization to carfilzomib in transplant-ineligable patients with newly diagnosed multiple myeloma.

Measurable Residual Disease and Decision-Making in Multiple Myeloma

Measurable (minimal) residual disease (MRD) has already proven to be one of the most important prognostic factors in multiple myeloma (MM). Each improvement in the depth of MRD testing has led to superior discrimination of outcomes, and sustained MRD negativity seems to be paramount to durable responses. Peripheral blood assays to assess for MRD are still under investigation but hold promise as complementary tools to bone marrow MRD assays such as next-generation sequencing and flow cytometry. Herein, the authors explore the evidence and potential benefits and drawbacks of MRD-adapted clinical decision-making in MM.

Is There Still a Role for Stem Cell Transplantation in Multiple Myeloma?

No therapy in multiple myeloma has been as extensively investigated as stem cell transplantation following high-dose chemotherapy. A search of the national library of medicine in February 2023 revealed over 27,000 publications covering stem cell transplantation. No other treatment for multiple myeloma has been so vigorously investigated. However, given the rapid advances seen in the treatment of multiple myeloma, it is legitimate to ask whether the technique first introduced in 1983 by Thomas McIlwain still has relevance. In 1984,Barlogie introduced infusional vincristine, doxorubicin, and dexamethasone and in 1986 published a first series on high-dose therapy with autologous marrow-derived stem cells. At this point, the only available therapies were melphalan, prednisone, other intensive steroids such as methylprednisolone, and interferon. Cyclophosphamide was used both orally and parenterally. VBMCP was introduced as a combination therapy at Memorial Hospital subsequently shown not to be superior to melphalan and prednisone.

Role of Consolidation and Maintenance

Consolidation therapy consists of short-term therapy after stem cell transplant in multiple myeloma. Key consolidation trials have shown mixed results on whether consolidation should be included after transplant, leading to varied clinical practice. Maintenance therapy consists of long-term, typically fixed-duration or indefinite, therapy. Standard-risk patients typically receive single-agent therapy, whereas high-risk may benefit from doublet therapy and beyond. Adverse events and quality of life concerns should be considered, as optimal duration of maintenance therapy continues to be studied.

The role of maintenance therapy following autologous stem cell transplantation in newly diagnosed multiple myeloma: Considerations on behalf of the Chronic Malignancies Working Party of the EBMT

Recent treatment advancements in multiple myeloma have led to significant improvements in patient outcomes. Maintenance therapy following autologous haematopoietic stem cell transplantation (AHCT) is now standard of care and has been demonstrated to prolong and deepen treatment responses. Currently, lenalidomide remains the single agent that has been approved for maintenance post-AHCT in Europe and the USA which, if tolerated, is continued until disease progression. The treatment landscape is rapidly expanding however, and the optimal personalised maintenance approach for a patient is becoming more complex. Treatment outcomes for patients with high-risk disease remain poor and choice of maintenance in this population also remains unclear. This review article evaluates up-to-date literature regarding established maintenance approaches. It further analyses ongoing studies exploring maintenance regimens using combination and novel agents, approaches to maintenance in patients with cytogenetic high-risk disease and minimal residual disease response-adapted strategies that reflect the current evolving treatment paradigm.

Predictors of unsustained measurable residual disease negativity in transplant-eligible patients with multiple myeloma

ABSTRACT

The role of measurable residual disease (MRD) negativity as a biomarker to stop treatment is being investigated in transplant-eligible patients with multiple myeloma (MM). Thus, it is important to identify risk factors of MRD resurgence and/or progressive disease (PD) among patients achieving undetectable MRD to avoid undertreating them. Here, we studied 267 newly diagnosed transplant-eligible patients with MM enrolled in the GEM2012MENOS65 and GEM2014MAIN clinical trials who achieved MRD negativity by next-generation flow cytometry. After a median follow-up of 73 months since the first MRD negative assessment, 111 of the 267 (42%) patients showed MRD resurgence and/or PD. The only prognostic factors at diagnosis that predicted MRD resurgence and/or PD were an International Staging System (ISS) 3 and the presence of ≥0.01% circulating tumor cells (CTCs). Failure to achieve MRD negativity after induction also predicted higher risk of MRD resurgence and/or PD. Patients having 0 vs 1 vs ≥2 risk factors (ISS 3, ≥0.01% CTCs, and late MRD negativity) showed 5-year rates of MRD resurgence and/or PD of 16%, 33%, and 57%, respectively (P < .001). Thus, these easily measurable risk factors could help refine the selection of patients for whom treatment cessation after MRD negativity is being investigated in clinical trials. This trial was registered at www.clinicaltrials.gov as NCT01916252 and NCT02406144.

Polyclonal immunoglobulin recovery in patients with newly diagnosed myeloma receiving maintenance therapy after autologous haematopoietic stem cell transplantation with either carfilzomib, lenalidomide and dexamethasone or lenalidomide alone: Subanalysis of the randomized phase 3 ATLAS trial

Previous studies suggest that postautologous stem cell transplant (ASCT) recovery of polyclonal immunoglobulin from immunoparesis in patients with multiple myeloma is a positive prognostic marker. We performed a longitudinal analysis of polyclonal immunoglobulin concentrations and unique B-cell sequences in patients enrolled in the phase 3 ATLAS trial that randomized 180 subjects to either carfilzomib, lenalidomide, dexamethasone (KRd) or lenalidomide (R) maintenance. In the KRd arm, standard-risk patients with minimal residual disease negativity after six cycles de-escalated to R alone after cycle 8. One year from the initiation of maintenance at least partial recovery of polyclonal immunoglobulin was observed in more patients on the R arm (58/66, p < 0.001) and in those who de-escalated from KRd to R (27/38, p < 0.001) compared to the KRd arm (9/36). In patients who switched from KRd to R, the concentrations of uninvolved immunoglobulin and the number of B-cell unique sequences increased over time, approaching values observed in the R arm. There were no differences in progression-free survival between the patients with at least partial immunoglobulin recovery and the remaining population. Our analysis indicates that patients receiving continuous therapy after ASCT experience prolonged immunoparesis, limiting prognostic significance of polyclonal immunoglobulin recovery in this setting.

Venous Thromboembolism Risk in Patients With Newly Diagnosed Multiple Myeloma Treated with Carfilzomib or Bortezomib in Combination With Lenalidomide and Dexamethasone

BACKGROUND

Multiple myeloma (MM), as well as some treatments for MM, increase the risk of venous thromboembolism (VTE). Prior literature suggests carfilzomib, lenalidomide, and dexamethasone (KRd) may have a higher incidence of thromboembolic events compared with bortezomib, lenalidomide, and dexamethasone (VRd). We aimed to evaluate VTE risk with KRd induction compared to VRd at a large academic medical center in the United States.

MATERIALS AND METHODS

We retrospectively reviewed patients with newly diagnosed MM presenting at a single institution. Patients were followed for objectively diagnosed VTE events for 6 months following the start of induction therapy.

RESULTS

A total of 209 patients were included, with 69 (33%) receiving KRd and 140 (67%) receiving VRd. Overall, 18 patients (9%) had a VTE event, with 5 (7%) in the KRd cohort and 13 (9%) in the VRd cohort (P = .80). Treatment with KRd was not associated with an increased risk of VTE compared to VRd (HR 0.74; 95% CI 0.26-2.08; P = .57).

CONCLUSION

In this cohort, KRd was not associated with an increase in VTE risk compared to VRd, contrary to prior literature.

Aiming for the cure in myeloma: Putting our best foot forward

Frontline therapy for multiple myeloma (MM) is evolving to include novel combinations that can achieve unprecedented deep response rates. Several treatment strategies exist, varying in induction regimen composition, use of transplant and or consolidation and maintenance. In this sea of different treatment permutations, the overarching theme is the powerful prognostic factors of disease risk and achievement of minimal residual disease (MRD) negativity. MM has significant inter-patient variability that requires treatment to be individualized. Risk-adapted and response-adapted strategies which are increasingly being explored to define the extent and duration of therapy, and eventually aim for functional curability. In addition, with T-cell redirection therapies rapidly revolutionizing myeloma treatments, the current standard of care for myeloma will change. This review analyzes the current relevant literature in upfront therapy for fit myeloma patients and provides suggestions for treatment approach while novel clinical trials are maturing.

Measurable residual disease in peripheral blood in myeloma: dream or reality

PURPOSE OF REVIEW

Therapeutic advancements in multiple myeloma have led to increasingly deeper and more durable responses, creating a need for highly sensitive and applicable techniques for measurable residual disease (MRD) assessment. Bone marrow assays can deeply assess for MRD, but it is not conducive to performing frequent and dynamic evaluations, which may be needed for MRD-adapted treatment approaches. Recently, numerous techniques for MRD assessment in peripheral blood have come under investigation, and their integration into routine clinical practice is eagerly anticipated.

RECENT FINDINGS

The identification of circulating tumor cells (CTCs), evaluation of cell-free DNA, and measuring monoclonal protein concentration with mass spectrometry are promising research areas for assessing myeloma in peripheral blood. CTCs assessment and cell-free DNA may carry prognostic significance, but they lack the sensitivity of bone marrow-based techniques. Mass spectrometry has already been implemented in clinical practice in certain centers, but its full potential has yet to be fully realized. This review focuses on recent developments in these fields, emphasizing the potential future roles of these assessments.

SUMMARY

MRD assessment in peripheral blood is still in the development stage but holds promise for not only complementing bone marrow based evaluations but also potential for improving sensitivity.

Intensifying treatment in PET-positive multiple myeloma patients after upfront autologous stem cell transplantation

18F-Fluorodeoxyglucose positron emission tomography/computed tomography (PET) positivity after first-line treatment with autologous stem cell transplantation (ASCT) in multiple myeloma is strongly correlated with reduced progression-free and overall survival. However, PET-positive patients who achieve PET negativity after treatment seem to have comparable outcomes to patients who were PET negative at diagnosis. Hence, giving PET-positive patients additional treatment may improve their outcome. In this phase II study, we screened first-line patients with very good partial response (VGPR) or better after ASCT with PET. PET-positive patients received four 28-day cycles of carfilzomib-lenalidomide-dexamethasone (KRd). Flow cytometry-based minimal residual disease (MRD) analysis was performed before and after treatment for correlation with PET. Overall, 159 patients were screened with PET. A total of 53 patients (33%) were PET positive and 57% of PET-positive patients were MRD negative, demonstrating that these response assessments are complementary. KRd consolidation converted 33% of PET-positive patients into PET negativity. MRD-negative patients were more likely to convert than MRD-positive patients. In summary, PET after ASCT detected residual disease in a substantial proportion of patients in VGPR or better, even in patients who were MRD negative, and KRd consolidation treatment changed PET status in 33% of patients.

High serum miR-223-3p expression level predicts complete response and prolonged overall survival in multiple myeloma patients undergoing autologous hematopoietic stem cell transplantation

Introduction

AHSCT is the treatment of choice for newly diagnosed patients with transplant-eligible multiple myeloma (MM). However, considerable variability in response to autologous hematopoietic stem cell transplantation (AHSCT) results in only 50% of patients achieving complete response (CR) after AHSCT, which is directly associated with improved progression-free and overall survival (OS). In this study, we aimed to investigate the potential predictive role of selected serum miRNAs in MM patients who underwent AHSCT.

Patients and methods

Serum expression level of 6 miRNAs: miR-221-3p, miR-15b-5p, miR-223-3p, miR-320c, miR-361-3p, and miR-150-5p was evaluated in 51 patients who underwent AHSCT. Blood samples were collected at two time points: before conditioning chemotherapy (T1) and fourteen days after transplant (+14) (T2).

Results

All selected miRNAs significantly changed their expression level across the procedure- two were up-regulated after AHSCT: hsa-miR-320c (FC 1.42, p<0.0001) and hsa-miR-361-3p (FC 1.35, p=0.0168); four were down-regulated: hsa-miR-15b-5p (FC 0.53, p<0.0001), hsa-miR-221-3p (FC 0.78, p=0.0004), hsa-miR-223-3p (FC 0.74, p=0.0015) and hsa-miR-150-5p (FC 0.75, p=0.0080). Notably, before AHSCT, hsa-miR-223-3p was down-regulated in International Staging System (ISS) III patients (FC=0.76, p=0.0155), and hsa-miR-320c was up-regulated (FC=1.27, p=0.0470). These differences became non-significant after AHSCT. Eight (15.69%) patients achieved CR before AHSCT and 17 patients (33.33%) at +100 days after AHSCT. In multivariate logistic regression analysis, achievement of CR after induction and hsa-miR-223-3p at T1 were independent predictors of CR after AHSCT. In multivariate Cox regression analysis, hsa-miR-223-3p at T1 expression level was associated with prolonged OS (HR 0.06, 95%CI: 0.00 - 0.99, p=0.0488).

Conclusion

Serum expression of has-miR-223-3p is a predictor of CR and prolonged OS in MM patients undergoing AHSCT.

Proteasome inhibition in combination with immunotherapies: State-of-the-Art in multiple myeloma

Multiple myeloma (MM) is a malignant plasma cell disorder accounting for around 1.8% of all neoplastic diseases. Nowadays, clinicians have a broad arsenal of drugs at their disposal for the treatment of MM, such as proteasome inhibitors, immunomodulatory drugs, monoclonal antibodies, bispecific antibodies, CAR T-cell therapies and antibody-drug conjugates. In this paper we briefly highlight essential clinical elements relating to proteasome inhibitors, such as bortezomib, carfilzomib and ixazomib. Studies suggest that the early use of immunotherapy may improve outcomes significantly. Therefore, in our review we specifically focus on the combination therapy of proteasome inhibitors with novel immunotherapies and/or transplant. A high number of patients develop PI resistance. Thus, we also review new generation PIs, such as marizomib, oprozomib (ONX0912) and delanzomib (CEP-18770) and their combinations with immunotherapies.

Current Main Topics in Multiple Myeloma

Multiple Myeloma (MM) remains a difficult to treat disease mainly due to its biological heterogeneity, of which we are more and more knowledgeable thanks to the development of increasingly sensitive molecular methods that allow us to build better prognostication models. The biological diversity translates into a wide range of clinical outcomes from long-lasting remission in some patients to very early relapse in others. In NDMM transplant eligible (TE) patients, the incorporation of mAb as daratumumab in the induction regimens, followed by autologous stem cell transplantation (ASCT) and consolidation/maintenance therapy, has led to a significant improvement of PFS and OS.; however, this outcome remains poor in ultra-high risk MM or in those who did not achieve a minimal residual disease (MRD) negativity. Several trials are exploring cytogenetic risk-adapted and MRD-driven therapies in these patients. Similarly, quadruplets-containing daratumumab, particularly when administered as continuous therapies, have improved outcome of patients not eligible for autologous transplant (NTE). Patients who become refractory to conventional therapies have noticeably poor outcomes, making their treatment a difficult challenge in need of novel strategies. In this review, we will focus on the main points regarding risk stratification, treatment and monitoring of MM, highlighting the most recent evidence that could modify the management of this still incurable disease.