Allogeneic transplantation of multiple myeloma patients may allow long-term survival in carefully selected patients with acceptable toxicity and preserved quality of life

Efficacy and survival outcome of allogeneic stem-cell transplantation in multiple myeloma: meta-analysis in the recent 10 years

Introduction

Allogeneic hematopoietic cell transplantation (alloHCT) possessed direct cytotoxicity and graft-versus-multiple myeloma effect (GvMM). Growing trials have shown survival benefits of performing alloHCT in both newly diagnosed and relapsed MM.

Methods

We aimed to provide a comprehensive analysis in the recent 10 years to verify the efficacy and survival outcome of alloHCT in MM patients. A total of 61 studies which provide data between 14/04/2013 and 14/04/2023 and a total of 15,294 data from MM patients who had undergone alloSCT were included in our study. The best response rates (CR, VGPR, PR) and survival outcomes (1-, 2-, 3-,5-, and 10-year OS, PFS, NRM) were assessed. We further conducted meta-analysis in the NDMM/frontline setting and RRMM/salvage setting independently.

Results

The pooled estimate CR, VGPR, and PR rates were 0.45, 0.21, and 0.24, respectively. The pooled estimates of 1-, 2-, 3-, 5-, and 10-year OS were 0.69, 0.57, 0.45, 0.45, and 0.36, respectively; the pooled estimates of 1-, 2-, 3-, 5-, and 10-year PFS were 0.47, 0.35, 0.24, 0.25, and 0.28, respectively; and the pooled estimates of 1-, 2-, 3-, 5-, and 10-year NRM were 0.16, 0.21, 0.16, 0.20, and 0.15, respectively. In the NDMM/upfront setting, the pooled estimate CR rate was 0.54, and those for 5-year OS, PFS, and NRM were 0.69, 0.40, and 0.11, respectively. In a relapsed setting, the pooled estimate CR rate was 0.31, and those for 5-year OS, PFS, and NRM were 0.24, 0.10, and 0.15, respectively.

Discussion

Our results showed constant OS, PFS, and NRM from the third year onwards till the 10th year, suggesting that alloSCT has sustained survival benefits. Good response rate and promising survival outcome were observed in the NDMM/ frontline setting.

Conclusion

Although comparing with other treatments, alloSCT had a lower response rate and poorer short-term survival outcome, long-term follow-up could reveal survival benefits of alloSCT in MM patients.

Physical activity and exercise motivation of multiple myeloma patients: a prospective cross-sectional study

BACKGROUND

Multiple myeloma (MM) is the second most common hematological malignancy with its prevalence increasing. Patients with symptomatic MM can show numerous comorbidities, affecting their quality of life (QoL). Physical activity (PA) may improve QoL but is not a standardized intervention of comprehensive cancer centers (CCCs). Since data on the PA of patients with MM are scarce, we aimed to prospectively assess fitness levels and patients' motivation to join PA-interventions at our CCC.

METHODS

We generated an exercise questionnaire to interview consecutive patients MM. We prospectively collected data on (a) past and current PA, defined by the World Health Organization (WHO) recommendations, (b) knowledge on exercise effects, (c) exercise motivation, and (d) willingness to participate in PA-interventions. Demographics, comorbidities, response, progression-free survival (PFS), and overall survival (OS) were assessed in 211 symptomatic patients MM.

RESULTS

While our patients were elderly and most showed bone involvement, their PA was similar to healthy individuals. Aerobic PA (≥ 60 minutes/week) was performed by 65%, and 25% exercised ≥ 150 minutes/week. WHO PA recommendations were fulfilled by 17% of patients. No sport activities or complete physical inactivity were observed in 35% and 16%, respectively. Notably, 38% were motivated to join MM-specific sport interventions. Self-reported knowledge of PA-induced benefits for patients cancer was high (82%), but only 27% knew which exercises were safe to perform.

CONCLUSION

This study provides an overview of the PA of patients MM. Our results suggest that the PA of patients MM might not be much lower than in the age-matched general population.

Allogeneic stem cell transplantation in multiple myeloma: is there still a place?

The introduction of novel agents dramatically improved response and outcomes of multiple myeloma (MM) and led to a sharp decline in the use of allogeneic hematopoietic stem-cell transplantation (allo-HSCT). Thus, recent guidelines do not recommend anymore allo-HSCT as consolidation in the first-line treatment of newly diagnosed MM, even in high-risk patients. In a relapsed/refractory setting, allo-HSCT is not routinely recommended but should only be performed within clinical trials in young and high-risk patients. Nonetheless, allo-HSCT still represents a potential curative approach that has been used for decades in the treatment of MM and plasma cell neoplasms with favorable results and may still represent a treatment option for carefully selected patients. Despite that promising results were obtained with CAR T-cell therapies and bispecific antibodies in triple- and penta-exposed/refractory MM, these patients will inevitably relapse. To date, less is known about outcomes of allo-HSCT in patients exposed to novel immunotherapeutic drugs. Therefore, allo-HSCT could represent a reasonable treatment choice for younger and high-risk patients who have relapsed after CAR T-cell therapies and bispecific antibodies as well as an alternative for patients not eligible to these treatments and in those countries where immunotherapies are not yet available. In the choice of conditioning, reduced intensity conditioning regimens are currently recommended for the lower toxicity and mortality. Moreover, the use of alternative donors, particularly haploidentical, has progressively increased in last years with results comparable to full matched donors. Finally, post-transplantation maintenance strategies are encouraged whenever feasible.

In search for cure of multiple myeloma

Not available.

Comparison of antibody-based immunotherapeutics for malignant hematological disease in an experimental murine model

ABSTRACT

Antibody-based immunotherapies have revolutionized leukemia and lymphoma treatment, with animal studies being crucial in evaluating effectiveness and side effects. By targeting the evolutionary conserved Slamf7 immune receptor, which is naturally expressed by the murine multiple myeloma cell line MPC-11, we have developed a syngeneic mouse model for direct comparison of 3 immunotherapies: monoclonal antibodies (mAb), bispecific T-cell engagers (BiTE), and chimeric antigen receptor (CAR) T cells (CART), all targeting Slamf7. Slamf7-BiTE is a bispecific single-chain antibody consisting of α-Slamf7 and α-CD3 Fv fragments joined through a Gly-Ser linker, and Slamf7-CART comprises the α-Slamf7 Fv fragment fused to the msCD8α transmembrane and msCD28, 4-1BB, and CD3ζ intracellular signaling domains. Slamf7-BiTE and Slamf7-CART effectively killed MPC-11 cells in vitro, independently of Slamf7-mediated inhibitory signaling by self-ligation. After chimerizing the constant region of the rat-anti-mouse Slamf7 antibody to mouse Fc-immunoglobulin G2a for enhanced effector functions, Slamf7-mAb triggered antigen-specific antibody-dependent cellular cytotoxicity by binding to Fcγ receptor IV. In vivo, all 3 immunotherapies showed antitumor effects against Slamf7-expressing targets. Unlike Slamf7-mAb, Slamf7-BiTE led to considerable side effects in test animals, including weight loss and general malaise, which were also observed to a lesser extent after Slamf7-CART infusion. In allogeneic transplant, Slamf7-BiTE and Slamf7-CART maintained activity compared with the nontransplant setting, whereas Slamf7-mAb displayed enhanced antimyeloma activity. In summary, our model faithfully replicates treatment efficacy and side effects detected after human immunotherapy. It aids in developing and improving immunotherapies and may help devise novel approaches to mitigate undesired effects in steady state and allogeneic stem cell transplantation.

[Clinical analysis of 14 patients aged ≤ 50 years with high-risk multiple myeloma treated with allogeneic hematopoietic stem cell transplantation]

Objective: To evaluate the efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in young patients with high-risk multiple myeloma (HRMM) and analyzed the factors affecting patient prognosis. Methods: In this retrospective study, we analyzed the clinical data of 14 patients with HRMM with cytogenetic abnormalities or high-risk biological factors who underwent allo-HSCT at the Hematopoietic Stem Cell Transplantation Center of the Institute of Hematology & Blood Diseases Hospital between November 2016 and November 2022. Results: There were seven males and seven females included in the study, with a median age of 39.5 (31-50) years at the time of allo-HSCT. The median number of treatment lines before transplantation was 2 (1-6) . Before allo-HSCT, 42.9% (6/14) of the patients did not achieve complete remission, while 35.7% (5/14) of the patients achieved measurable residual disease positivity. After transplantation, all patients were evaluated for their treatment response, and the overall response rate was 100% (14/14) . All 14 patients successfully underwent allo-HSCT, with median engraftment times for neutrophils and platelets of 11 (10-14) days and 13 (9-103) days, respectively. Acute grade Ⅱ-Ⅳ graft-versus-host disease (GVHD) occurred in five patients (35.7%) , and two patients (14.3%) developed moderate-to-severe chronic GVHD. The median follow-up time after allo-HSCT was 18.93 (4.10-72.53) months, with an expected 2-year transplant-related mortality rate of 7.1% (95% CI 0%-21.1%) and an expected 2-year overall survival rate of 92.9% (95% CI 80.3%-100.0%) . Moreover, the expected 1-year and 2-year progression-free survival rates were 92.9% (95% CI 80.3%-100.0%) and 66.0% (95% CI 39.4%-100.0%) , respectively, and the 2-year cumulative incidence of relapse was 28.9% (95% CI 0%-56.7%) . Upfront allo-HSCT following complete remission after induced therapy and the presence of chronic GVHD might be favorable prognostic factors. Conclusion: allo-HSCT is an effective treatment for improving the prognosis of young patients with HRMM.

Allogeneic stem cell transplant for multiple myeloma & myelofibrosis with split-dose busulfan, fludarabine & cyclophosphamide

Allogeneic stem cell transplant can have high morbidity and mortality in patients with myelofibrosis (MF) and multiple myeloma (MM). This phase 2 study used a novel myeloablative regimen of split-dose busulfan, fludarabine, and then post-transplant cyclophosphamide. Four patients with MF and 2 with MM were enrolled. At 1 year, non-relapse mortality was 33.3%, and overall survival was 50%. Incidence of acute and chronic GVHD was 33.3% and 16.7%, respectively. Those surviving beyond 1 year (MF = 1, MM = 2) had durable remissions with a median follow-up of 42 months. This small study demonstrates relative safety & favorable key outcomes using this novel approach.

Long-term outcomes of allogeneic stem cell transplant in multiple myeloma

Allogeneic stem cell transplant (allo SCT) for multiple myeloma (MM) is potentially curative in some, while toxic in many others. We retrospectively analyzed 85 patients diagnosed with MM who underwent allo SCT as frontline or salvage therapy between 2000 and 2022 at Mayo Clinic Rochester and examined patient outcomes and prognostic markers. Overall survival (OS), progression free survival (PFS), treatment related mortality (TRM), and relapse rates (RR) were estimated using the Kaplan Meier method and competing risk models. Median follow-up was 11.5 years. Median OS and PFS were 1.7 and 0.71 years, respectively. Five-year OS and PFS were 22.2% and 15.1%, respectively. One-year TRM was 23.5%. Twelve patients demonstrated durable overall survival, living 10+ years beyond their allo SCT. This subgroup was more likely to have no or one prior auto SCT (p = 0.03) and to have been transplanted between 2000 and 2010 (p = 0.03). Outcomes were poor in this cohort with long follow-up, with few patients surviving 5 years or more, and most relapsing or dying within 2 years. We would expect better outcomes and tolerability with an expanded array of novel therapeutics and would prefer them to allo SCT.

Second stem cell transplantation for treatment of relapsed/refractory multiple myeloma after first autologous stem cell transplant: A 15-year retrospective institutional analysis

Background

Multiple myeloma remains an incurable disease, with the majority of patients relapsing after autologous stem cell transplant (ASCT). After relapse, second transplant remains one of the therapeutic options, along with novel agents.

Methods

We reviewed the data of our patients who underwent ASCT for myeloma (N = 202) over the last two decades (2004-2019). Of these, 12 patients underwent a second transplant.

Results

Out of 12 patients, nine underwent second autologous stem cell transplant, whereas three received an allogeneic stem cell transplantation (Allo-SCT). Median progression-free survival (PFS) after the first ASCT was 32 months (5-84 months). Median interval between both the transplants was 35 months (4-159 months). Median age of our cohort which underwent second transplant was 56 years. Overall response rate (ORR) post-second transplant on day +100 was 83.3%, without any transplant-related mortality (TRM). With the use of preemptive plerixafor, none of our patients required a second day for stem cell harvest. Median CD34 dose of stem cells infused was 4.11 × 106/kg. Similar to the first ASCT, the median time to neutrophil and platelet engraftment was 11 and 12 days, respectively. At a median follow-up of 41 months, estimated 3-year PFS and overall survival (OS) was 37% ± 15% and 63% ± 15%, respectively.

Conclusion

">Among all relapsed myeloma patients who were transplant eligible, 11% underwent a second transplant. Second transplant is well tolerated with similar time to engraftment after first ASCT. Hence, we believe that second transplant is a feasible, cost-effective option in a resource-limited setting, which should be more widely utilized.

An objective assessment in newly diagnosed multiple myeloma to avoid treatment complications and strengthen therapy adherence

In heterogeneous multiple myeloma (MM) patients treatment decisions are challenging. The hypothesis was that adaptation of treatment intensity (dose reduction [DR] vs. none) according to an objective risk score (revised-myeloma comorbidity index [R-MCI]) rather than physician judgement alone may improve therapy efficacy and avoid toxicities. We performed this study in 250 consecutive MM patients who underwent a prospective fitness assessment at our center, after having received induction protocols based on physicians' judgement. DR, serious adverse events (SAE), response, progression-free survival (PFS) and overall survival (OS) were compared in fitness (fit, intermediate-fit, frail), age (<60, ≥70 years [y]) and therapy intensity subgroups at baseline and follow-up. Fit and <60 y patients were mostly treated with full intensity, whereas frail and ≥70 y patients usually received DR. Hematological and non-hematological SAE were more frequently seen in frail versus ≥70 y patients. Dose adaptations were mainly necessary in frail patients. OS and PFS were similar in fit and intermediate-fit but significantly worse in frail patients (P=0.0245/P<0.0001), whereas in age-based subgroups, OS and PFS differences did not reach significance (P=0.1362/P=0.0569). Non-hematological SAE were another negative predictor for impaired OS and PFS (P=0.0054/P=0.0021). In the follow-up performed at a median of 11 months after the first fitness assessment, the R-MCI improved or remained stable in 90% versus deteriorated in only 10% of patients. In conclusion, separation by R-MCI/frailty-defined subgroups was superior to age-based subgroups and can be used to improve tailored treatment. Fitter patients benefit from intensive therapies, whereas frail patients bear a need for initial DR.

Immunotherapy for the treatment of multiple myeloma

Despite advances in treatment for multiple myeloma, the majority of patients ultimately develop relapsed disease marked by immune evasion and resistance to standard therapy. Immunotherapy has emerged as a powerful tool for tumor-directed cytotoxicity with the unique potential to induce immune memory to reduce the risk of relapse. Understanding the specific mechanisms of immune dysregulation and dysfunction in advanced myeloma is critical to the development of further therapies that produce a durable response. Adoptive cellular therapy, most strikingly CAR T cell therapy, has demonstrated dramatic responses in the setting of refractory disease. Understanding the factors that contribute to immune evasion and the mechanisms of response and resistance to therapy will be critical to developing the next generation of adoptive cellular therapies, informing novel combination therapy, and determining the optimal time to incorporate immune therapy in the treatment of myeloma.

Efficacy and toxicity of carfilzomib- or bortezomib-based regimens for treatment of transplant-ineligible patients with newly diagnosed multiple myeloma: A meta-analysis

BACKGROUND

Multiple myeloma is a clonal disorder of malignant plasma cells that comprises approximately 10% of hematologic malignancies. The aim of this study was to investigate the efficacy and toxicity of carfilzomib- or bortezomib-based regimens for treatment of transplant-ineligible patients with newly diagnosed multiple myeloma by performing a meta-analysis of randomized controlled trials (RCTs).

METHODS

Data mining was conducted in March 2022 across PubMed, EMBASE and ClinicalTrials.gov. All published RCTs which assessed efficacy and toxicity of carfilzomib-based regimens treatment for transplant-ineligible patients with newly diagnosed multiple myeloma when compared with a bortezomib-based regimens were included.

RESULTS

Our meta-analysis showed that the overall response rate (ORR) (Odds ratio = 1.33, 95% CI 1.05-1.69, P = .02) was significantly higher in the carfilzomib-based regimens group than in the bortezomib-based regimens group. However, the difference in ORR did not translate into improvements in progression-free survival (PFS), overall survival (OS) and complete response rate (CRR). Adverse events of grade 3 or worse that occurred with a higher incidence in the carfilzomib-based regimens group compared with the bortezomib-based regimens group were dyspnea, hypertension, acute kidney injury, and heart failure.

CONCLUSIONS

The carfilzomib-based regimens did not improve PFS, OS and CRR compared with the bortezomib-based regimens in transplant-ineligible patients with newly diagnosed multiple myeloma, and they showed higher toxicity.

Allogeneic hematopoietic stem cell transplantation in patients with therapy-related hematologic malignancies developing after multiple myeloma

INTRODUCTION

Increasing survival of patients with multiple myeloma (MM) has resulted in an increased recognition of therapy-related hematological malignancies (t-MDS/AML, t-ALL, and t-CMML). There are limited data on the role of allogeneic hematopoietic stem cell transplantation (HCT) in this patient population.

PATIENTS AND METHODS

We retrospectively reviewed patients who underwent HCT for t-MDS/AML, t-ALL, and t-CMML developing after receiving treatment for MM at our center. Patients were analyzed for myeloma characteristics and therapy, time to diagnosis of therapy-related hematological neoplasms, clinical, laboratory characteristics, transplant details, relapse-free survival (RFS), and overall survival (OS).

RESULTS

Twenty patients underwent HCT for therapy-related hematological malignancies after MM (t-MDS/AML = 13, t-ALL = 6, t-CMML = 1). Median(range) age at time of transplant was 62.5 (49-73) years and 70% (n = 14) were male. The most common cytogenetic abnormality was complex/monosomal karyotype in 30% (n = 6) followed by monosomy/deletion of chromosome 5 or 7 in 15% (n = 3) of patients each. Donors were human leukocyte antigen matched (10/10 or 6/6) siblings in 30% (n = 6), unrelated in 60% (n = 12) and haploidentical in 10% (n = 2) patients. Estimated 2-year OS and RFS for the whole cohort were 53.1% and 47.2% respectively. There was a trend toward better survival in patients with t-ALL when compared to t-MDS/AML; however, the difference was not statistically significant. We did not find any pre-transplant or post-transplant factors that were predictive of survival outcomes after multivariate analysis.

CONCLUSIONS

Allogeneic HCT provides substantial long-term disease-free survival in a proportion of patients with MM-associated therapy-related hematological malignancies. Multicenter studies with more patients and longer follow-up may provide additional information about factors affecting outcomes.

Current Role of Allogeneic Stem Cell Transplantation in Multiple Myeloma

Major progress in the treatment of multiple myeloma has been made in the last several years. However, myeloma remains incurable and patients with high-risk cytogenetics or advanced stage disease have an even worsen survival. Only allogeneic transplantation may have curative potential in some patients. However, the high non-relapse mortality and incidence of chronic graft-versus-host disease have raised controversy regarding this procedure. In this review, we will address the role of upfront and delayed allogeneic transplant.

Cellular Immunotherapies for Multiple Myeloma: Current Status, Challenges, and Future Directions

Multiple myeloma (MM) remains incurable due to relapse, although the use of proteasome inhibitors, immunomodulatory drugs, CD38-targeting antibodies, and autologous stem cell transplantation (auto-SCT) significantly improve the clinical outcomes of patients with newly diagnosed MM. In recent years, the introduction of chimeric antigen receptor T-cell (CAR T-cell) therapy has brought hope to patients with refractory and relapsed MM. The graft-versus-myeloma effect of allogeneic SCT provides the possibility for curing a subset of MM patients. In this review, we summarize the recent advances and challenges of cellular immunotherapies for MM, focusing on auto-SCT, allogeneic SCT, and CAR T-cell approaches. We also discuss future directions, and propose a specific algorithm for cellular therapies for MM and probability of minimal residual disease-directed therapy.

Allogeneic Stem Cell Transplantation in Multiple Myeloma

The development of new inhibitory and immunological agents and combination therapies significantly improved response rates and survival of patients diagnosed with multiple myeloma (MM) in the last decade, but the disease is still considered to be incurable by current standards and the prognosis is dismal especially in high-risk groups and in relapsed and/or refractory patients. Allogeneic hematopoietic stem cell transplantation (allo-SCT) may enable long-term survival and even cure for individual patients via an immune-mediated graft-versus-myeloma (GvM) effect, but remains controversial due to relevant transplant-related risks, particularly immunosuppression and graft-versus-host disease, and a substantial non-relapse mortality. The decreased risk of disease progression may outweigh this treatment-related toxicity for young, fit patients in high-risk constellations with otherwise often poor long-term prognosis. Here, allo-SCT should be considered within clinical trials in first-line as part of a tandem approach to separate myeloablation achieved by high-dose chemotherapy with autologous SCT, and following allo-SCT with a reduced-intensity conditioning to minimize treatment-related organ toxicities but allow GvM effect. Our review aims to better define the role of allo-SCT in myeloma treatment particularly in the context of new immunomodulatory approaches.

Therapeutic Potential of Innate Lymphoid Cells for Multiple Myeloma Therapy

Innate lymphoid cells (ILCs) are a recently identified family of lymphocyte-like cells lacking a specific antigen receptor. They are part of the innate immune system. They play a key role in tissue homeostasis and also control inflammatory and neoplastic processes. In response to environmental stimuli, ILCs change their phenotype and functions, and influence the activity of other cells in the microenvironment. ILC dysfunction can lead to a wide variety of diseases, including cancer. ILC can be divided into three subgroups: ILC Group 1, comprising NK cells and ILC1; Group 2, including ILC2 alone; and Group 3, containing Lymphoid Tissue inducers (LTi) and ILC3 cells. While Group 1 ILCs mainly exert antitumour activity, Group 2 and Group 3 ILCs are protumorigenic in nature. A growing body of preclinical and clinical data support the role of ILCs in the pathogenesis of multiple myeloma (MM). Therefore, targeting ILCs may be of clinical benefit. In this manuscript, we review the available data on the role of ILCs in MM immunology and therapy.

Post-Transplantation Cyclophosphamide for Graft-versus- Host Disease Prophylaxis in Multiple Myeloma Patients Who Underwent Allogeneic Hematopoietic Cell Transplantation: First Comparison by Donor Type. A Study from the Chronic Malignancies Working Party of the European Society for Blood and Marrow Transplantation

Graft-versus-host disease (GVHD) remains among the major causes of treatment failure in patients with multiple myeloma (MM) undergoing allogeneic hematopoietic cell transplantation (allo-HCT). The use of post-transplantation cyclophosphamide (PT-Cy) is now a well-established and widely used method for GVHD prophylaxis after HLA haploidentical HCT. However, the rationale for using PT-Cy in the setting of matched donor transplantation is less apparent, given the lesser degree of bidirectional alloreactivity. In this retrospective study, we investigated the role of PT-Cy as GVHD prophylaxis in patients with multiple myeloma underoing allo-HCT, among different donor types, to determine cumulative incidence of acute and chronic GVHD and impact on engraftment, progression-free survival (PFS), GVHD-free/relapse- free survival (GRFS), overall survival (OS), and NRM A total of 295 patients with MM underwent allo-HCT using grafts from a matched related donor (MRD; n = 67), matched unrelated donor (MUD; n = 72), mismatched related or unrelated donor (MMRD/MMUD, 1 antigen; n = 27), or haploidentical donor (haplo; n = 129) using PT-Cy between 2012 and 2018. In addition to PT-Cy, agents used in GVHD prophylaxis included calcineurin inhibitors in 239 patients (81%), with mycophenolate mofetil in 184 of those 239 (77%). For grade II-IV acute GVHD, the cumulative incidence at day +100 was 30% (95% confidence interval [CI], 25% to 36%), 9% (95% CI, 5% to 12%) for grade III-IV acute GVHD, and 27% (95% CI, 21% to 32%) for chronic GVHD (limited, 21%; extensive, 6%), with no differences by donor type. The median time to neutrophil engraftment was 19d (95% CI, 18-19), with no significant difference by donor type. The median time to platelet engraftment was delayed in haploidentical donor graft recipients (27 days versus 21 days; P < .001). Two-year OS, PFS, GRFS, and NRM were 51% (95% CI, 45% to 58%), 26% (95% CI, 20% to 32%), 24% (95% CI, 18% to 30%), and 19% (95% CI, 14% to 24%), respectively, with no significant difference between different donor types. In multivariable analyses, compared with the haplo donors, the use of MRDs was associated with significantly better OS (hazard ratio [HR], 0.6; 95% CI, 0.38 to 0.95; P = .029), and the use of MUDs was associated with a significantly higher GRFS (HR, 0.63; 95% CI, 0.42 to 0.97; P = .034). There was a trend toward improved PFS with use of MUDs (HR, 0.69; 95% CI, 0.46 to 1.04; P = .08). Our data show that PT-Cy in MM patients undergoing allo-HCT resulted in low rates of acute and chronic GVHD and led to favorable survival, especially in the matched related donor setting. © 2021 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Harnessing the Immune System to Fight Multiple Myeloma

Multiple myeloma (MM) is a heterogeneous plasma cell malignancy differing substantially in clinical behavior, prognosis, and response to treatment. With the advent of novel therapies, many patients achieve long-lasting remissions, but some experience aggressive and treatment refractory relapses. So far, MM is considered incurable. Myeloma pathogenesis can broadly be explained by two interacting mechanisms, intraclonal evolution of cancer cells and development of an immunosuppressive tumor microenvironment. Failures in isotype class switching and somatic hypermutations result in the neoplastic transformation typical of MM and other B cell malignancies. Interestingly, although genetic alterations occur and evolve over time, they are also present in premalignant stages, which never progress to MM, suggesting that genetic mutations are necessary but not sufficient for myeloma transformation. Changes in composition and function of the immune cells are associated with loss of effective immune surveillance, which might represent another mechanism driving malignant transformation. During the last decade, the traditional view on myeloma treatment has changed dramatically. It is increasingly evident that treatment strategies solely based on targeting intrinsic properties of myeloma cells are insufficient. Lately, approaches that redirect the cells of the otherwise suppressed immune system to take control over myeloma have emerged. Evidence of utility of this principle was initially established by the observation of the graft-versus-myeloma effect in allogeneic stem cell-transplanted patients. A variety of new strategies to harness both innate and antigen-specific immunity against MM have recently been developed and intensively tested in clinical trials. This review aims to give readers a basic understanding of how the immune system can be engaged to treat MM, to summarize the main immunotherapeutic modalities, their current role in clinical care, and future prospects.

Choosing the Right Therapy for Patients with Relapsed/Refractory Multiple Myeloma (RRMM) in Consideration of Patient-, Disease- and Treatment-Related Factors

Treatment of relapsed/refractory multiple myeloma (RRMM) is more complex today due to the availability of novel therapeutic options, mostly applied as combination regimens. immunotherapy options have especially increased substantially, likewise the understanding that patient-, disease- and treatment-related factors should be considered at all stages of the disease. RRMM is based on definitions of the international myeloma working group (IMWG) and includes biochemical progression, such as paraprotein increase, or symptomatic relapse with CRAB criteria (hypercalcemia, renal impairment, anemia, bone lesions). When choosing RRMM-treatment, the biochemical markers for progression and severity of the disease, dynamic of disease relapse, type and number of prior therapy lines, including toxicity and underlying health status, need to be considered, and shared decision making should be pursued. Objectively characterizing health status via geriatric assessment (GA) at each multiple myeloma (MM) treatment decision point has been shown to be a better estimate than via age and comorbidities alone. The well-established national comprehensive cancer network, IMWG, European myeloma network and other national treatment algorithms consider these issues. Ideally, GA-based clinical trials should be supported in the future to choose wisely and efficaciously from available intervention and treatment options in often-older MM adults in order to further improve morbidity and mortality.

Allogeneic hematopoietic stem cell transplantation in patients with multiple myeloma

Aim. To analyze the effectiveness of allogeneic hematopoietic stem cell transplantation (allo-HSCT) from a related HLA-identical donor in patients with multiple myeloma (MM). Materials and methods. From 2013 to 2018, the study included 8 patients (6 men, 2 women) aged from 27 to 55 years (median 39 years) with MM who underwent allo-HSCT from a related HLA-identical donor (7 patients after auto-HSCT, in 1 case without previous auto-transplantation). All patients required 2 or more lines of induction therapy, while the achieved antitumor effect was unstable. Before allo-HSCT, complete and very good partial remission was determined in isolated cases, in 4 patients the response was regarded as partial remission, stabilization in 1 observation, progression in 1 patient. All patients underwent reduced intensity conditioning (fludarabine 30 mg/m2 6 days + busulfan 4 mg/kg 2 days). Immunosuppressive therapy included the administration of antithymocyte globulin and post-transplant cyclophosphamide. Results. Severe acute GVHD (grade 34) was observed in 3 (37.5%) cases, which resulted in death in 1 case. A stable antitumor response was achieved in 5 (62.5%) patients, complete remission lasts for 2986 months after allo-HSCT. Specific therapy for these patients is not carried out. The 7-year progression-free survival rate was 75%, the 7-year overall survival rate was 84%, with a median follow-up of 65 months. The transplant-related mortality was 12.5%. Conclusion. Allo-HSCT is considered as an alternative method of therapy for young patients with aggressive MM. Allo-HSCT in MM in some cases leads to long-term immunological control of the tumor.

Allogeneic Stem Cell Transplantation in Patients with High-Risk Multiple Myeloma: Utopia or Continuous Challenge in Aiming for Cure?

OPINION STATEMENT

Nowadays, several novel agents have been introduced in the treatment of multiple myeloma, not only resulting in high response rates and prolonged survival but also offering good quality of life. However, the potential of cure, especially for patients with advanced or unfavorable disease features, remains elusive. Allogeneic hematopoietic stem cell transplantation, based mainly on the graft vs. myeloma effect, can offer prolonged disease control and probability of cure but unfortunately at the cost of considerable transplant-related toxicity rates. Therefore, the role of allogeneic hematopoietic stem cell transplantation in the treatment of multiple myeloma has been called into question. Recently, several studies, particularly those with long-term follow-up, demonstrated a trend of survival superiority for allografted patients with high-risk disease. These data fuel again the interest in allogeneic stem cell transplantation for selected patients with high-risk multiple myeloma, especially if the high remission rates which can be achieved with the currently used treatment protocols could be long-life sustained through the additional exploitation of the long-lasting anti-multiple myeloma effect, originating from the allograft.

Comparison of the prognostic significance of 5 comorbidity scores and 12 functional tests in a prospective multiple myeloma patient cohort

BACKGROUND

Because of the various therapeutic options available for multiple myeloma (MM), remarkable interest exists today in individualized therapeutic concepts based on patients' fitness. The main objectives of this study were to compare different comorbidity scores and functional tests with respect to their impact on survival (overall survival [OS] and progression-free survival [PFS]); develop a time-efficient, MM-specific functional assessment (FA); and evaluate changes in patients' FA during treatment.

METHODS

The authors performed a prospective FA in 266 consecutive patients with MM at their initial diagnosis. This included 5 comorbidity scores and 12 commonly used geriatric functional tests. To evaluate changes in the course of treatment, the authors reassessed these 17 tests after ≥6 months. The entire analysis included 7327 FA tests.

RESULTS

On the basis of univariate and multivariate Cox regression analyses, the authors identified 4 of the 17 evaluated scores and functional tests as most relevant: the Revised Myeloma Comorbidity Index (R-MCI), Activity of Daily Living (ADL), the Mini-Mental State Examination (MMSE), and the quality-of-life 12-Item Short Form Health Survey Physical Composite Scale (SF-12 PCS). These showed precise group differences for fit, (intermediate-fit), and frail patients in OS and PFS: the 3-year OS rates were 90%, 74%, and 43% via the R-MCI for fit, intermediate-fit, and frail patients, respectively (P = .0006); 80% and 66% via the ADL for fit and frail patients, respectively (P = .0159); 78% and 48% via the MMSE for fit and frail patients, respectively (P = .0001); and 86% and 66% via the SF-12 PCS for fit and frail patients, respectively (P = .0091). In follow-up analyses, 16 of 17 FA tests improved, mostly in younger patients (<70 years old) and responding patients (partial remission or better).

CONCLUSIONS

Patients may recover from functional and physical limitations under applied MM therapy. The newly established MM-specific FA (via the R-MCI, ADL, MMSE, and SF-12 PCS) allows a precise evaluation of the prognosis and risk status in MM. Its use may improve treatment tolerability and should be validated to individualize MM treatment decisions in the future.

LAY SUMMARY

The authors performed a prospective functional assessment (FA) in 266 consecutive patients with multiple myeloma at their initial diagnosis. On the basis of univariate and multivariate Cox regression analyses, the authors identified 4 of 17 initially evaluated scores and functional tests as most relevant: the Revised Myeloma Comorbidity Index, Activity of Daily Living, the Mini-Mental State Examination, and the quality-of-life 12-Item Short Form Health Survey Physical Composite Scale. The authors checked the stability of the final model by applying forward and stepwise selection. To evaluate changes in the course of treatment, they reassessed these 17 tests in 165 patients after ≥6 months: 16 of the 17 FA tests improved, mostly in younger patients (<70 years old) and responding patients (partial remission or better).

Successful Treatment of Relapsed/Refractory Extramedullary Multiple Myeloma With Anti-BCMA CAR-T Cell Therapy Followed by Haploidentical Hematopoietic Stem Cell Transplantation: A Case Report and a Review of the Contemporary Literature

Extramedullary multiple myeloma (EMM) is an aggressive sub-entity of multiple myeloma (MM). Despite an excellent improvement in survival for most patients with MM over recent decades, the overall survival (OS) of patients with EMM was usually not longer than 3 years. Standard treatment for patients with EMM has not been established, and their management is particularly challenging. We presented a heavily pretreated young patient with relapsed EMM and refractoriness to a proteasome inhibitor (PI; bortezomib), a next-generation PI (ixazomib), immunomodulatory drugs (IMiDs; lenalidomide), autologous hematopoietic stem cell transplantation (ASCT), and monoclonal antibody (directed against CD38: daratumumab) and indicated that myeloablative haploidentical hematopoietic stem cell transplantation (haploidentical-HSCT) as a salvage treatment of relapse after a chimeric antigen receptor (CAR)-T cell therapy that targeted B-cell maturation antigen (BCMA) (NCT04650724) is feasible. Taken together of the contemporary literature, the promising results on the effect of anti-BCMA CAR-T cell therapy and allogeneic HSCT might present a proof-of-principle for patients with EMM, and therefore, patients with the disease need to be included in future studies.

Long-term outcome after allogeneic stem cell transplantation in multiple myeloma

The role of allogeneic hematopoietic stem cell transplantation (allo-SCT) in multiple myeloma is controversial. We analyzed the results of 205 patients transplanted in one center during 2000–2017. Transplantation was performed on 75 patients without a previous autologous SCT (upfront-allo), on 74 as tandem transplant (auto-allo), and on 56 patients after relapse. Median overall survival (OS) was 9.9 years for upfront-allo, 11.2 years for auto-allo, and 3.9 years for the relapse group (p = 0.015). Progression-free survival (PFS) was 2.4, 2.4, and 0.9 years, respectively (p < 0.001). Non-relapse mortality at 5 years was 8% overall, with no significant difference between the groups. Post-relapse survival was 4.1 years for upfront-allo and auto-allo, and 2.6 years for the relapse group (p = 0.066). Survival of high-risk patients was reduced. In multivariate analysis, the auto-allo group had improved OS and chronic graft-versus-host disease was advantageous in terms of PFS, OS, and relapse incidence. Late relapses occurred in all groups. Allo-SCT resulted in long-term survival in a small subgroup of patients. Our results indicate that auto-allo-SCT is feasible and could be considered for younger patients in the upfront setting.

A new decade: novel immunotherapies on the horizon for relapsed/refractory multiple myeloma

INTRODUCTION

Survival in multiple myeloma (MM) has improved due to the ongoing revolution of therapeutic approaches. Nevertheless, many patients relapse, and additional novel approaches are required to prolong remissions and prevent disease progression.

AREAS COVERED

Considering the success of monoclonal antibodies (mAbs) against CD38 and SLAMF7 in relapsed/refractory MM (R/R MM), additional antigens expressed on malignant plasma cells are being investigated as treatment targets. Among these, many trials are focusing on B cell maturation antigen (BCMA), using either antibody-drug conjugates (ADCs), bispecific T cell engagers (TCE), or chimeric antigen receptor T cells (CAR-T). Other potential targets include the myeloma markers CD138, GPRC5D, FcRH5, the plasma cell differentiating factors APRIL, TACI and BAFF, and the immune checkpoint proteins CD47 and TIGIT. Additionally, novel immunomodulatory Cereblon E3 Ligase Modulators (CELMoDs) offer the potential to overcome resistance to conventional immunomodulatory agents. Based upon PubMed and abstract searches primarily from the past 4 years, here we review the data supporting novel immunotherapies for R/R MM.

EXPERT OPINION

Overcoming disease resistance remains a challenge in R/R MM. Novel therapeutic approaches targeting MM antigens and/or enhancing immune cell function offer the potential to prolong survival and are actively being investigated in clinical trials.

Boosting Immunity against Multiple Myeloma

Despite the improvement of patient's outcome obtained by the current use of immunomodulatory drugs, proteasome inhibitors or anti-CD38 monoclonal antibodies, multiple myeloma (MM) remains an incurable disease. More recently, the testing in clinical trials of novel drugs such as anti-BCMA CAR-T cells, antibody-drug conjugates or bispecific antibodies broadened the possibility of improving patients' survival. However, thus far, these treatment strategies have not been able to steadily eliminate all malignant cells, and the aim has been to induce a long-term complete response with minimal residual disease (MRD)-negative status. In this sense, approaches that target not only myeloma cells but also the surrounding microenvironment are promising strategies to achieve a sustained MRD negativity with prolonged survival. This review provides an overview of current and future strategies used for immunomodulation of MM focusing on the impact on bone marrow (BM) immunome.

Role of Stem Cell Transplantation in Multiple Myeloma

Autologous stem cell transplantation (auto-SCT) has been the standard of care in eligible newly diagnosed multiple myeloma (MM) patients. Outcomes of patients with MM have improved significantly due to the advent of several novel drugs. Upfront use of these drugs in induction therapy has significantly increased the rate and depth of responses that have translated into longer remission and survival. This has now raised a debate regarding the role and relevance of auto-SCT in the management of myeloma. However, clinical trials have confirmed the utility of auto-SCT even in the era of novel drugs. Tandem auto-SCT followed by maintenance has shown a progression-free survival (PFS) benefit in high-risk MM, and hence can be considered in young and fit patients with high-risk disease. Auto-SCT has the advantages of resetting the bone marrow microenvironment, short-lived toxicity compared to the long-term physical and financial toxicities of continued chemotherapy in the absence of SCT, very low transplant-related mortality (TRM) in high volume centers, and providing longer disease-free survival when followed by maintenance therapy. Allogeneic SCT is one potentially curative option for MM, albeit with an increased risk of death due to high TRM. Strategies to modulate the graft-versus-host disease (GVHD) while maintaining or improving the graft-versus-myeloma (GVM) effect could place allogeneic SCT back in the treatment armamentarium of MM.

Improved survival in multiple Myeloma patients undergoing autologous stem cell transplantation is entirely in the standard cytogenetic risk groups

INTRODUCTION

Novel drugs and drug combinations have improved outcomes for multiple myeloma patients. However, subgroups of patients still have a poor progression-free survival (PFS) and overall survival (OS). In an attempt to identify how the novel drugs affect the outcome in standard-risk and high-risk patients, respectively, we have investigated 715 multiple myeloma (MM) patients who have undergone high dose treatment followed by autologous stem cell transplantation at our center during 1995 - 2020. Outcomes during three time periods, 1995-1999 (period I), 2000-2009 (period II), and 2010-2020 (period III), were compared separately for standard-risk and high-risk patients. Risk stratification was based on chromosome analysis for periods II and III.

RESULTS

The whole cohort of patients showed significantly improved OS with time during the three periods being at a median of 5.8, 7.0, and 10.0 years, respectively. There is also a weak tendency for improved PFS, that is, a median of 2.4, 2.6, and 2.9 years, respectively, during the same periods. However, the separate analysis of standard-risk and high-risk patients showed that the overall improvement with time was due to improved standard-risk patients (median OS 8.4 years for the period I and not reached for period II and III). In contrast, no significant improvement was seen in high-risk patients. For patients with del17p, PFS was even worse during period III as compared to period II (median 1.6 vs 3.2 years respectively).

CONCLUSION

Our results show that the dramatic improvement in outcome for MM patients during the last 20 years only applies for standard-risk patients, while high-risk MM patients still are doing poorly, indicating that the novel drugs developed during this time are preferentially effective in standard-risk patients. New treatment modalities like CAR-T cells, CAR-NK cells, and/or bispecific antibodies should be tried in clinical studies early in the course of the disease, especially in patients with high-risk cytogenetics.

Why Immunotherapy Fails in Multiple Myeloma

Multiple myeloma remains an incurable disease despite great advances in its therapeutic landscape. Increasing evidence supports the belief that immune dysfunction plays an important role in the disease pathogenesis, progression, and drug resistance. Recent efforts have focused on harnessing the immune system to exert anti-myeloma effects with encouraging outcomes. First-in-class anti-CD38 monoclonal antibody, daratumumab, now forms part of standard treatment regimens in relapsed and refractory settings and is shifting to front-line treatments. However, a non-negligible number of patients will progress and be triple refractory from the first line of treatment. Antibody-drug conjugates, bispecific antibodies, and chimeric antigen receptors (CAR) are being developed in a heavily pretreated setting with outstanding results. Belantamab mafodotin-blmf has already received approval and other anti-B-cell maturation antigen (BCMA) therapies (CARs and bispecific antibodies are expected to be integrated in therapeutic options against myeloma soon. Nonetheless, immunotherapy faces different challenges in terms of efficacy and safety, and manufacturing and economic drawbacks associated with such a line of therapy pose additional obstacles to broadening its use. In this review, we described the most important clinical data on immunotherapeutic agents, delineated the limitations that lie in immunotherapy, and provided potential insights to overcome such issues.

Defining and Managing High-Risk Multiple Myeloma: Current Concepts

Multiple myeloma is a very heterogeneous disease. Despite advances in diagnostics and therapeutics, a subset of patients still experiences abbreviated responses to therapy, frequent relapses, and short survival and is considered to have high-risk multiple myeloma (HRMM). Stage III diagnosis according to the International Staging System; the presence of del(17p), t(4;14), or t(14;16) by fluorescence in situ hybridization; certain gene expression patterns; high serum lactic dehydrogenase level; and the presence of extramedullary disease at diagnosis are all considered indicators of HRMM. More recent evidence shows that patients who experience response to therapy but with a high burden of measurable residual disease or persistence of abnormal FDG uptake on PET/CT scan after initial therapy also have unfavorable outcomes, shaping the concept of dynamic risk assessment. Triplet therapy with proteasome inhibitors, immunomodulatory agents, and corticosteroids and autologous hematopoietic cell transplantation remain the pillars of HRMM therapy. Recent evidence indicates a benefit of immunotherapy with anti-CD38 monoclonal antibodies in HRMM. Future trials will inform the impact of novel immunotherapeutic approaches, including T-cell engagers, CAR T cells, and nonimmunotherapeutic approaches in HRMM. Those agents are likely to be deployed early in the disease course in the setting of risk- and response-adapted trials.

History of hematopoietic cell transplantation: challenges and progress

After more than 60 years of research in allogeneic hematopoietic cell transplantation (HCT), this therapy has advanced from one that was declared dead in the 1960s to a standard treatment of otherwise fatal malignant and non-malignant blood diseases. To date, close to 1.5 million hematopoietic cell transplants have been performed in more than 1,500 transplantation centers worldwide. This review will highlight the enormous efforts by numerous investigators throughout the world who have brought the experimental field of HCT to clinical reality, examine ongoing challenges, and provide insights for the future.

Evaluation of EuroFlow minimal residual disease measurement and donor chimerism monitoring following tandem auto-allogeneic transplantation for multiple myeloma

Prognostic factors for multiple myeloma (MM) after allogeneic haemopoietic stem cell transplantation (alloHSCT) are poorly characterised. Two potential factors include minimal residual disease (MRD) and CD3⁺ donor-specific chimerism. We retrospectively examined 93 consecutive patients who received upfront or deferred tandem auto-alloHSCT. Bone marrow (Euroflow) MRD was assessed pre-alloHSCT and 3-monthly post-alloHSCT. CD3⁺ donor chimerism was assessed at D30, D60, D90, 6 m and 12 m post-alloHSCT. There was no statistical difference between upfront and deferred transplants in progression free survival (PFS) (34 m vs. 15 m respectively, p = 0.20) and overall survival (OS) (75.5 m vs. 62.7 m respectively, p = 0.56). Patients who were MRD-positive post-alloHSCT had inferior PFS to MRD-negative patients from 6 m (6 m HR 3.32, p = 0.02; 9 m HR 4.08, p = 0.003; 12 m HR 4.47, p = 0.008). Attainment or maintenance of MRD-negativity predicted reduced relapse risk (23.5% vs. 62.5%, p = 0.04). However, there was no significant difference in OS between the MRD-negative and positive groups. Full CD3⁺ donor chimerism at early time points (D30 and D90) was associated with increased risk of acute GVHD (D30 p < 0.001, D90 p = 0.006) and extensive chronic GVHD (D90 p = 0.04), but not PFS or OS. These data support the use of sequential MRD evaluation post-alloHSCT to inform intervention to eradicate persistent or emergent MRD-positive disease.

Physical activity is associated with less comorbidity, better treatment tolerance and improved response in patients with multiple myeloma undergoing stem cell transplantation

OBJECTIVES

Multiple myeloma (MM) is the second most common hematological malignancy. Progression free survival (PFS) and overall survival (OS) have substantially improved, nonetheless MM usually remains incurable. Patients with active disease may be affected by numerous comorbidities, including fatigue, depression and osteolytic lesions, which influence their quality of life (QoL). Albeit, it is known that exercising is beneficial for patients' QoL, few clinical trials are available in patients with MM. We therefore aimed to compare comorbidities and clinical outcome in physically active and inactive patients with MM.

MATERIAL AND METHODS

We defined physical activity according to WHO criteria (150 min of moderate activity and two sessions of resistance training/week). We matched 53 physically active patients with 53 controls (for age, gender, cytogenetics, disease stage, and therapy) and compared the cohorts for incidence of comorbidities/MM symptoms (osteolytic lesions, anemia, infections, fatigue, depression, Revised-Myeloma Comorbidity Index [R-MCI]) and clinical outcome (treatment tolerance, responses to therapy, PFS and OS) in a retrospective audit. All patients were newly diagnosed with MM and received autologous stem cell transplantations (ASCT) between 2001 and 2017.

RESULTS

Physically active patients showed superior outcomes in R-MCI (p = 0.0005), fatigue (p = 0.0063), treatment tolerance (p = 0.0258) and hospital stays (p = 0.0072). Furthermore, they showed better treatment responses (p = 0.0366), especially complete remission (CR; p = 0.0018) as well as better OS and PFS.

CONCLUSION

Physical activity in patients with MM undergoing ASCT seemed associated with better overall clinical outcome. Randomized clinical trials are required to understand the benefits and devise strategies for improving exercising among patients with MM.

Allogenic stem cell transplantation in multiple myeloma: dead or alive and kicking?

Multiple myeloma (MM) accounts for about 1.8% of all cancers and slightly over 17% of hematologic malignancies. Despite improvements in outcomes in recent years, currently, there is still no cure for this disease. Although allogeneic stem cell transplantation (Allo-SCT) is a potentially curative treatment, given the armamentarium of highly effective therapeutic options and a pipeline of novel agents, many opinion leaders sustain that there is no longer a role for this approach. Of note, several studies that did not include novel agents reported long-term molecular remissions, and possibly a cure, in a subset of patients after reduced-intensity conditioning/nonmyeloablative (RIC/NM) Allo-SCT. However, there are no current data supporting upfront Allo-SCT. Prospective trials combining the so-called "graft-versus-myeloma" effect and new drugs are an unmet medical need in high-risk patients. Early relapse after first-line treatment, which identifies patients with poor prognosis independently of other prognostic factors, could become a clinical indication.

Emerging immunotherapies in multiple myeloma

Despite considerable advances in treatment approaches in the past two decades, multiple myeloma remains an incurable disease. Treatments for myeloma continue to evolve with many emerging immunotherapies. The first immunotherapy used to treat hematologic cancers, including multiple myeloma, was an allogeneic stem cell transplant. In the mid-2000s, immunomodulatory drugs thalidomide, lenalidomide, and subsequently pomalidomide were proven to be effective in multiple myeloma and substantially improved survival. The next wave of immunotherapies for multiple myeloma included the monoclonal antibodies daratumumab and elotuzumab, which were approved by the Food and Drug Administration in 2015. Subsequently, a variety of immunotherapies have been developed for multiple myeloma, including chimeric antigen receptor T cells, bispecific antibodies, antibody drug conjugates, and checkpoint inhibitors. Many of these emerging treatments target the B cell maturation antigen, which is expressed on plasma cells, although several other novel receptors are also being studied. This review summarizes the evidence of these various immunotherapies, their mechanism of action, and data from clinical trials regarding the treatments' safety and efficacy.

Targeting NF-κB Signaling for Multiple Myeloma

Multiple myeloma (MM) is the second most common hematologic malignancy in the world. Even though survival rates have significantly risen over the past years, MM remains incurable, and is also far from reaching the point of being managed as a chronic disease. This paper reviews the evolution of MM therapies, focusing on anti-MM drugs that target the molecular mechanisms of nuclear factor kappa B (NF-κB) signaling. We also provide our perspectives on contemporary research findings and insights for future drug development.

Prognostic Factors for Postrelapse Survival after ex Vivo CD34+-Selected (T Cell-Depleted) Allogeneic Hematopoietic Cell Transplantation in Multiple Myeloma

Allogeneic hematopoietic cell transplantation (alloHCT) for multiple myeloma (MM), with its underlying graft-versus-tumor capacity, is a potentially curative approach for high-risk patients. Relapse is the main cause of treatment failure, but predictors for postrelapse survival are not well characterized. We conducted a retrospective analysis to evaluate predictors for postrelapse overall survival (OS) in 60 MM patients who progressed after myeloablative T cell-depleted alloHCT. The median patient age was 56 years, and 82% had high-risk cytogenetics. Patients received a median of 4 lines of therapy pre-HCT, and 88% achieved at least a partial response (PR) before alloHCT. Of the 38% who received preemptive post-HCT therapy, 13 received donor lymphocyte infusions (DLIs) and 10 received other interventions. Relapse was defined as very early (<6 months; 28%), early (6 to 24 months; 50%), or late (>24 months; 22%). At relapse, 27% presented with extramedullary disease (EMD). The median postrelapse overall survival (OS) by time to relapse was 4 months for the very early relapse group, 17 months for the early relapse group, and 72 months for the late relapse group (P = .002). Older age, relapse with EMD, <PR before alloHCT, <PR by day +100, and no maintenance were prognostic for inferior postrelapse OS on univariate analysis. On multivariate analysis adjusted for age and sex, very early relapse (hazard ratio [HR], 4.37; 95% confidence interval [CI], 1.42 to 13.5), relapse with EMD (HR, 5.20; 95% CI, 2.10 to 12.9), and DLI for relapse prevention (HR, .11; 95% CI, 2.10 to 12.9) were significant predictors for postrelapse survival. Despite their shared inherent high-risk status, patients with MM have significantly disparate post-HCT relapse courses, with some demonstrating long-term survival despite relapse.

Allogeneic Stem Cell Transplantation in Relapsed/Refractory Multiple Myeloma Treatment: Is It Still Relevant? (Running Title: The Role of Salvage alloSCT in MM)

Background: Despite offering an attractive option, the role of allogeneic stem cell transplantation (alloSCT) for treatment of multiple myeloma (MM) remains unclear. Methods: Recognizing the paucity of data in the Asian population, we retrospectively evaluated the outcomes of 24 patients (median age 52) undergoing alloSCT between April 2003 and November 2017. Results: The median time from diagnosis to alloSCT was 39.4 months. The majority of the patients (70.8%) underwent alloSCT followed by reduced intensity conditioning regimens after a median of five lines of therapy. Among 24 patients, 15 patients (62.5%) had a high-risk MM feature. The two-year relapse-free survival (RFS) and overall survival (OS) of the total patients were 29.2 ± 9.3% and 44.3 ± 10.3%, respectively. Patients who were treated with less chemotherapy lines (<5) before alloSCT had a prolonged RFS and OS. All patients (seven patients) who received a myeloablative conditioning regimen had high-risk features, but two out of seven patients showed long-term survival without lasting sequelae. Nine patients (37.5%) experienced non-relapse mortality (NRM) within one year after alloSCT (the one-year cumulative incidence of NRM was 38.3 ± 10.1%). Conclusion: AlloSCT can still be implemented as effective salvage option in the treatment of relapsed/refractory high-risk MM. The optimal timing of alloSCT remains to be determined.

Allogeneic Transplantation in Multiple Myeloma-Does It Still Have a Place?

Novel drugs have improved survival for patients with multiple myeloma in recent years. However, the disease is still fatal. Allogeneic stem cell transplantation (Allo) has proven to cure some patients with the disease, but its role is controversial due to relatively high transplant-related toxicity and mortality (nonrelapse mortality, NRM). Using nonmyeloablative reduced-intensity conditioning (RIC), both toxicity and NRM can be reduced, and RICAllo is, therefore, an option for subgroups of patients. Upfront tandem autologous/RICAllo (Auto/RICAllo) was shown to be superior to single Auto or tandem Auto/Auto in both progression-free (PFS) and overall survival (OS) in two prospective studies with long-term follow-up, while three similarly designed studies did not detect a difference. A recent update of pooled patient data from four of these studies showed significantly superior PFS and OS with Auto/RICAllo. Importantly, none of these studies showed inferior results with Auto/RICAllo in patients less than 70 years of age. Auto/RICAllo appears to overcome some poor risk cytogenetic markers. Encouraging results have also been seen in treatment of relapsed patients. Combining Allo with new proteasome inhibitors and immunomodulatory drugs may further improve results. Other encouraging new cell therapies such as with CAR T-cells, NK- and CAR NK-cells may well have a place in combination with RICAllo. Such studies are warranted.

Management of older and frail patients with multiple myeloma in the Portuguese routine clinical practice: Deliberations and recommendations from an expert panel of hematologists

The management of older patients with Multiple Myeloma (MM) is particularly challenging due to the highly heterogeneous nature of this population, both in terms of physical and cognitive functioning. Older patients may be divided into fit, intermediate and frail, with variable abilities to tolerate treatments. A careful and correct assessment of the frailty status is thus paramount for the success of therapy and for improving outcomes. With the aging of the European population, the number of older patients with MM is rapidly growing. We hereby present the deliberations and recommendations from an expert panel of Portuguese hematologists conducted to discuss the management of this population, including how to stratify and treat older patients with MM according to their frailty status. The use of frailty tools is critical for the development of individualized risk-adapted treatment strategies and to minimize the risk of under or overtreatment. Aggressive therapies should be used in fitter patients to improve survival outcomes, while frail patients should generally be treated with less toxic approaches to control symptoms while minimizing toxicity. In intermediate-fit patients, low-dose triplets are recommended to achieve a balance between improving survival and maintaining quality of life. The management of older patients with MM should be performed by a multidisciplinary team in view of their advanced age and high prevalence of comorbidities. The inclusion of older and frail patients in future clinical trials investigating treatment regimens for MM is crucial to evaluate treatment feasibility and to improve clinical decision making in this population.

Risk of disease recurrence and survival in patients with multiple myeloma: A German Study Group analysis using a conditional survival approach with long-term follow-up of 815 patients

BACKGROUND

Unlike the traditional method of overall survival prediction in patients with cancer, conditional survival predicts the survival of patients dynamically throughout the course of disease, identifying how a prognosis evolves over time.

METHODS

The authors assessed 815 consecutive patients with multiple myeloma through the German Study Group on Multiple Myeloma (Deutsche Studiengruppe Multiples Myelom; DSMM) incentive. Over 10 variables, including patient-specific and multiple myeloma-specific parameters, were analyzed at the time of initial diagnosis and repeatedly during follow-up. The probability of survival for another 5 years was calculated according to disease-related and host-related risks. Multivariate Cox models were used to determine baseline and updated prognostic factors for survival.

RESULTS

The median follow-up and overall survival were 10.3 years and 5.1 years, respectively. When comparing 5-year conditional survival probabilities from the data derived at the time of initial diagnosis with those updated over time, substantially differing prognoses were observed when follow-up data were used. Multivariate Cox regression models for cohorts surviving 0 to 5 years demonstrated hazard ratios (HRs) for patients aged <60 years, 60 to 69 years, and >70 years of 1, 1.68, and 3.17, respectively. These HRs for age were found to decline for patients surviving 5 years, as well as for those with advanced stages of disease (II/III) and unfavorable cytogenetics, whereas progressive disease remained an important factor in patients surviving 1 year, 3 years, and 5 years, with HRs of 1.85, 2.11, and 2.14, respectively.

CONCLUSIONS

To the authors' knowledge, the current study is the first analysis of conditional survival in patients with multiple myeloma using both baseline and follow-up risk parameters, demonstrating that regular risk assessment throughout the course of disease and complete follow-up provide a more reliable conditional survival estimation than baseline assessment alone.

Long-term survival and polyclonal immunoglobulin reconstitution after allogeneic stem cell transplantation in multiple myeloma

Despite significant progress made in the treatment of patients with multiple myeloma (MM) in the last decade, for patients with early relapse or rapidly progressing high-risk disease, allogeneic hematopoietic stem cell transplantation (SCT) might be an option leading to long-term survival. Here, we retrospectively analyzed the outcomes of 90 MM patients who received allogeneic SCT in our center between 1999 and 2017. We specifically assessed the association of impaired humoral immune reconstitution, referred to as immunoparesis, and post-transplant survival. Sixty-four patients received allogeneic SCT in relapse following 2–7 lines of therapy; 26 patients received upfront tandem autologous-allogeneic SCT. With a median follow-up of 76 months, OS and PFS were 52.6% (95% CI 42.9–64.3) and 36.4% (95% CI 27.6–47.9) at 2 years and 38.6% (95% CI 29.2–51.1) and 25.3% (95% CI 17.5–36.4) at 5 years, respectively. Receiving more than two therapy lines prior to transplantation was an independent risk factor for OS (HR 3.68, 95% CI 2.02–6.70) and PFS (HR 3.69, 95% CI 2.09–6.50). In a landmark analysis at day 200, prolonged immunoparesis was associated with reduced OS (HR 3.22, 95% CI 1.14–9.11). Allogeneic stem cell transplantation offers an additional treatment element that may lead to long-term remission in selected patients with poor prognosis, probably exploiting graft-versus-myeloma effects. Immunoparesis could potentially serve as an indicator for impaired survival following allogeneic transplantation, an observation to be further studied prospectively.

Multiple myeloma with central nervous system relapse

Central nervous system involvement in multiple myeloma is a rare complication but carries a very poor prognosis. We provide a review of current literature, including presentation, treatment and survival data, and describe our experience in a regional hematologic malignancy diagnosis center where, over a 15-year period, ten cases were identified. Although the median age of onset, frequently between 50-60 years, is comparatively young, those diagnosed usually have a preceding diagnosis of multiple myeloma and often have had several lines of treatment. We discuss putative underlying factors such as prior treatment and associations including possible risk factors and features suggestive of a distinct biology. Central nervous system involvement may be challenging to diagnose in myeloma, displaying heterogeneous symptoms that can be confounded by neurological symptoms caused by the typical features of myeloma or treatment side-effects. We discuss the clinical features, imaging and laboratory methods used in diagnosis, and highlight the importance of considering this rare complication when neurological symptoms occur at presentation or, more commonly, during the disease pathway. In the absence of clinical trial data to inform an evidence-based approach to treatment, we discuss current and novel treatment options. Finally, we propose the establishment of an International Registry of such cases as the best way to collect and subsequently disseminate presentation, diagnostic and treatment outcome data on this rare complication of multiple myeloma.

Hematopoietic stem cell transplantation for blood cancers in the era of precision medicine and immunotherapy

Hematopoietic stem cell transplantation (HCT) has been an integral component in the treatment of many hematologic malignancies. Since the development of HCT nearly 50 years ago, the role of this modality has evolved as newer treatment approaches have been developed and integrated into the standard of care. In the last decade, novel and highly active targeted therapies and immunotherapies have been approved for many hematologic malignancies, raising the question of whether HCT continues to retain its prominent role in the treatment paradigms of various hematologic malignancies. In this review, the authors have described the current role of autologous and allogeneic HCT in the treatment of patients with acute leukemias, aggressive B-cell lymphomas, and multiple myeloma and discussed how novel targeted therapies and immunotherapies have changed the potential need, timing, and goal of HCT in patients with these diseases.