The biological and clinical impact of deletions before and after large chromosomal gains in multiple myeloma.

Acquisition of a hyperdiploid (HY) karyotype or immunoglobulin heavy chain (IGH) translocations are considered key initiating events in multiple myeloma (MM). To explore if other genomic events can precede these events, we analyzed whole-genome sequencing (WGS) data from 1173 MM samples. Integrating molecular time and structural variants (SV) within early chromosomal duplications, we indeed identified pre-gain deletions in 9.4% of HY patients without IGH translocations, challenging HY as the earliest somatic event. Remarkably, these deletions affected tumor suppressor genes (TSG) and/or oncogenes in 2.4% of HY patients without IGH translocations, supporting their role in MM pathogenesis. Furthermore, our study points to post-gain deletions as novel driver mechanisms in MM. Using multi-omics approaches to investigate their biological impact, we found associations with poor clinical outcome in newly diagnosed patients and profound effects on both oncogene and TSG activity, despite the diploid gene status. Overall, this study provides novel insights into the temporal dynamics of genomic alterations in MM.

Resolving therapy resistance mechanisms in multiple myeloma by multiomics subclone analysis.

Intratumor heterogeneity as a clinical challenge becomes most evident after several treatment lines, when multidrug-resistant subclones accumulate. To address this challenge, the characterization of resistance mechanisms at the subclonal level is key to identify common vulnerabilities. In this study, we integrate whole-genome sequencing, single-cell (sc) transcriptomics (scRNA sequencing), and chromatin accessibility (scATAC sequencing) together with mitochondrial DNA mutations to define subclonal architecture and evolution for longitudinal samples from 15 patients with relapsed or refractory multiple myeloma. We assess transcriptomic and epigenomic changes to resolve the multifactorial nature of therapy resistance and relate it to the parallel occurrence of different mechanisms: (1) preexisting epigenetic profiles of subclones associated with survival advantages, (2) converging phenotypic adaptation of genetically distinct subclones, and (3) subclone-specific interactions of myeloma and bone marrow microenvironment cells. Our study showcases how an integrative multiomics analysis can be applied to track and characterize distinct multidrug-resistant subclones over time for the identification of molecular targets against them.

A phase 2 clinical trial of combined BRAF/MEK inhibition for BRAFV600E-mutated multiple myeloma.

Activating BRAF mutations are found in a small subset of patients with newly diagnosed multiple myeloma, but prevalence increases in late-stage, refractory disease, and the mutations are associated with adverse outcome. This prospective single-arm, open-label, multicenter phase 2 trial assessed the efficacy and safety of combined BRAF/MEK inhibition, using encorafenib and binimetinib, in patients with relapsed/refractory multiple myeloma (RRMM) carrying a BRAFV600E mutation. Patients received 450 mg encorafenib once daily and binimetinib 45 mg twice daily. The primary end point was the overall response rate achieved within the first year after start of treatment according to International Myeloma Working Group criteria. Twelve RRMM patients with a median of 5 prior lines of therapy were enrolled. The overall response rate was 83.3%, with 10 patients achieving at least a partial response. The median progression-free survival was 5.6 months, and overall survival was 55% at 24 months. Emerging resistance to therapy was driven by RAS mutations and structural variants involving the BRAF locus. This is the first prospective clinical trial to demonstrate that combined BRAF/MEK inhibition is highly effective in patients with BRAFV600E-mutated RRMM, and it represents a successful targeted precision medicine approach in this disease. This trial was registered at www.clinicaltrials.gov as #NCT02834364.

Artificial intelligence-based, volumetric assessment of the bone marrow metabolic activity in [18F]FDG PET/CT predicts survival in multiple myeloma.

PURPOSE: Multiple myeloma (MM) is a highly heterogeneous disease with wide variations in patient outcome. [18F]FDG PET/CT can provide prognostic information in MM, but it is hampered by issues regarding standardization of scan interpretation. Our group has recently demonstrated the feasibility of automated, volumetric assessment of bone marrow (BM) metabolic activity on PET/CT using a novel artificial intelligence (AI)-based tool. Accordingly, the aim of the current study is to investigate the prognostic role of whole-body calculations of BM metabolism in patients with newly diagnosed MM using this AI tool. MATERIALS AND METHODS: Forty-four, previously untreated MM patients underwent whole-body [18F]FDG PET/CT. Automated PET/CT image segmentation and volumetric quantification of BM metabolism were based on an initial CT-based segmentation of the skeleton, its transfer to the standardized uptake value (SUV) PET images, subsequent application of different SUV thresholds, and refinement of the resulting regions using postprocessing. In the present analysis, ten different uptake thresholds (AI approaches), based on reference organs or absolute SUV values, were applied for definition of pathological tracer uptake and subsequent calculation of the whole-body metabolic tumor volume (MTV) and total lesion glycolysis (TLG). Correlation analysis was performed between the automated PET values and histopathological results of the BM as well as patients' progression-free survival (PFS) and overall survival (OS). Receiver operating characteristic (ROC) curve analysis was used to investigate the discrimination performance of MTV and TLG for prediction of 2-year PFS. The prognostic performance of the new Italian Myeloma criteria for PET Use (IMPeTUs) was also investigated. RESULTS: Median follow-up [95% CI] of the patient cohort was 110 months [105-123 months]. AI-based BM segmentation and calculation of MTV and TLG were feasible in all patients. A significant, positive, moderate correlation was observed between the automated quantitative whole-body PET/CT parameters, MTV and TLG, and BM plasma cell infiltration for all ten [18F]FDG uptake thresholds. With regard to PFS, univariable analysis for both MTV and TLG predicted patient outcome reasonably well for all AI approaches. Adjusting for cytogenetic abnormalities and BM plasma cell infiltration rate, multivariable analysis also showed prognostic significance for high MTV, which defined pathological [18F]FDG uptake in the BM via the liver. In terms of OS, univariable and multivariable analysis showed that whole-body MTV, again mainly using liver uptake as reference, was significantly associated with shorter survival. In line with these findings, ROC curve analysis showed that MTV and TLG, assessed using liver-based cut-offs, could predict 2-year PFS rates. The application of IMPeTUs showed that the number of focal hypermetabolic BM lesions and extramedullary disease had an adverse effect on PFS. CONCLUSIONS: The AI-based, whole-body calculations of BM metabolism via the parameters MTV and TLG not only correlate with the degree of BM plasma cell infiltration, but also predict patient survival in MM. In particular, the parameter MTV, using the liver uptake as reference for BM segmentation, provides solid prognostic information for disease progression. In addition to highlighting the prognostic significance of automated, global volumetric estimation of metabolic tumor burden, these data open up new perspectives towards solving the complex problem of interpreting PET scans in MM with a simple, fast, and robust method that is not affected by operator-dependent interventions.

Reproducible Radiomics Features from Multi-MRI-Scanner Test-Retest-Study: Influence on Performance and Generalizability of Models.

BACKGROUND: Radiomics models trained on data from one center typically show a decline of performance when applied to data from external centers, hindering their introduction into large-scale clinical practice. Current expert recommendations suggest to use only reproducible radiomics features isolated by multiscanner test-retest experiments, which might help to overcome the problem of limited generalizability to external data. PURPOSE: To evaluate the influence of using only a subset of robust radiomics features, defined in a prior in vivo multi-MRI-scanner test-retest-study, on the performance and generalizability of radiomics models. STUDY TYPE: Retrospective. POPULATION: Patients with monoclonal plasma cell disorders. Training set (117 MRIs from center 1); internal test set (42 MRIs from center 1); external test set (143 MRIs from center 2-8). FIELD STRENGTH/SEQUENCE: 1.5T and 3.0T; T1-weighted turbo spin echo. ASSESSMENT: The task for the radiomics models was to predict plasma cell infiltration, determined by bone marrow biopsy, noninvasively from MRI. Radiomics machine learning models, including linear regressor, support vector regressor (SVR), and random forest regressor (RFR), were trained on data from center 1, using either all radiomics features, or using only reproducible radiomics features. Models were tested on an internal (center 1) and a multicentric external data set (center 2-8). STATISTICAL TESTS: Pearson correlation coefficient r and mean absolute error (MAE) between predicted and actual plasma cell infiltration. Fisher's z-transformation, Wilcoxon signed-rank test, Wilcoxon rank-sum test; significance level P < 0.05. RESULTS: When using only reproducible features compared with all features, the performance of the SVR on the external test set significantly improved (r = 0.43 vs. r = 0.18 and MAE = 22.6 vs. MAE = 28.2). For the RFR, the performance on the external test set deteriorated when using only reproducible instead of all radiomics features (r = 0.33 vs. r = 0.44, P = 0.29 and MAE = 21.9 vs. MAE = 20.5, P = 0.10). CONCLUSION: Using only reproducible radiomics features improves the external performance of some, but not all machine learning models, and did not automatically lead to an improvement of the external performance of the overall best radiomics model. TECHNICAL EFFICACY: Stage 2.

Retrospective study on pomalidomide-PACE as a salvage regimen in aggressive relapsed and refractory multiple myeloma.

OBJECTIVES: Despite major advances in treatment options for multiple myeloma (MM), patients refractory to the main drug classes and those with aggressive, especially extramedullary disease, still face a dismal outcome. For these patients, effective therapeutic options are urgently warranted. METHODS: In this retrospective study, we report on the safety and efficacy of the intensive combination regimen of pomalidomide plus cisplatin, doxorubicin, cyclophosphamide, and etoposide (Pom-PACE) in patients with relapsed refractory MM (RRMM) or plasma cell leukemia (PCL). A study population of 20 consecutive patients treated with Pom-PACE at two academic centers was included for analysis. All patients had to have a confirmed relapse according to International Myeloma Working Group criteria and adequate organ function prior to the start of therapy. Data were collected by reviewing medical charts. Exploratory analyses were performed with regard to efficacy and safety. RESULTS: Patients were heavily pretreated with a median number of four prior therapies (range: 1-10). All patients were exposed to immunomodulators, proteasome inhibitors, and alkylating agents, 80% were double-class refractory, 40% were triple-class refractory. Extramedullary MM or PCL were present in 15 patients (75%). Overall response rate (ORR) was 68%, with 31% achieving at least a very good partial response. Responses were achieved rapidly with an ORR of 64% after one cycle. Median progression-free survival was 8.9 months (0.92-not reached [NR]) and median overall survival was 11.8 months (3-40.6). Pom-PACE was associated with significant toxicity. All evaluable patients experienced Grade 4 hematological toxicity. However, no treatment related mortality was observed. CONCLUSION: Pomalidomide-PACE was able to induce rapid responses in heavily pretreated, aggressive RRMM with a manageable toxicity profile and therefore offers an effective salvage regimen and a potential bridging strategy to further treatment options such as chimeric antigen receptor T-cell therapy.

Molecular Long-Term Analysis of the GMMG-HD4 Trial in Multiple Myeloma-Patterns of Association of Chromosomal Aberrations with Response and Proliferation Determining Survival in Selecting Treatments in View of Limited Resources in Low- and Middle-Income Countries.

Based on the lack of differences in progression-free and overall survival after a median follow-up of 93 months in our HOVON-65/GMMG-HD4 trial (German part; n = 395) randomizing VAD induction (vincristin/adriamycin/dexamthasone)/tandem-transplantation/thalidomide-maintenance vs. PAD induction (bortezomib/adriamycin/dexamethasone)/tandem transplantation/bortezomib maintenance, we discern how chromosomal aberrations determine long-term prognosis by different patterns of association with proliferation and treatment-dependent response, whether responses achieved by different regimens are equal regarding prognosis, and whether subpopulations of patients could be defined as treatable without upfront "novel agents" in cases of limited resources, e.g., in low- or middle-income countries. Serum parameters and risk factors were assessed in 395 patients. CD138-purified plasma cells were subjected to fluorescence in situ hybridization (n = 354) and gene expression profiling (n = 204). We found chromosomal aberrations to be associated in four patterns with survival, proliferation, and response: deletion (del) del17p13, del8p21, del13q14, (gain) 1q21+, and translocation t(4;14) (all adverse) associate with higher proliferation. Of these, del17p is associated with an adverse response (pattern 1), and 1q21+, t(4;14), and del13q14 with a treatment-dependent better response (pattern 2). Hyperdiploidy associates with lower proliferation without impacting response or survival (pattern 3). Translocation t(11;14) has no association with survival but a treatment-dependent adverse response (pattern 4). Significantly fewer patients reach a near-complete response or better with "conventional" (VAD) vs. bortezomib-based treatment after induction or high-dose melphalan. These patients, however, show significantly better median progression-free and overall survival. Molecularly, patients responding to the two regimens differ in gene expression, indicating distinct biological properties of the responding myeloma cells. Patients with normal renal function (89.4%), low cytogenetic risk (72.5%), or low proliferation rate (37.9%) neither benefit in progression-free nor overall survival from bortezomib-based upfront treatment. We conclude that response level, the treatment by which it is achieved, and molecular background determine long-term prognosis. Chromosomal aberrations are associated in four patterns with proliferation and treatment-dependent responses. Associations with faster and deeper responses can be deceptive in the case of prognostically adverse aberrations 1q21+ and t(4;14). Far from advocating a return to "outdated" treatments, if resources do not permit state-of-the-art-treatment, normal renal function and/or molecular profiling identifies patient subpopulations doing well without upfront "novel agents".

Clonal hematopoiesis with DNMT3A and PPM1D mutations impairs regeneration in autologous stem cell transplant recipients.

Clonal hematopoiesis (CH) is an age-related condition driven by stem and progenitor cells harboring recurrent mutations linked to myeloid neoplasms. Currently, potential effects on hematopoiesis, stem cell function and regenerative potential under stress conditions are unknown. We performed targeted DNA sequencing of 457 hematopoietic stem cell grafts collected for autologous stem cell transplantation (ASCT) in myeloma patients and correlated our findings with high-dimensional longitudinal clinical and laboratory data (26,510 data points for blood cell counts/serum values in 25 days around transplantation). We detected CHrelated mutations in 152 patients (33.3%). Since many patients (n=54) harbored multiple CH mutations in one or more genes, we applied a non-negative matrix factorization (NMF) clustering algorithm to identify genes that are commonly co-mutated in an unbiased approach. Patients with CH were assigned to one of three clusters (C1-C3) and compared to patients without CH (C0) in a gene specific manner. To study the dynamics of blood cell regeneration following ASCT, we developed a time-dependent linear mixed effect model to validate differences in blood cell count trajectories amongst different clusters. The results demonstrated that C2, composed of patients with DNMT3A and PPM1D single and co-mutated CH, correlated with reduced stem cell yields and delayed platelet count recovery following ASCT. Also, the benefit of maintenance therapy was particularly strong in C2 patients. Taken together, these data indicate an impaired regenerative potential of hematopoietic stem cell grafts harboring CH with DNMT3A and PPM1D mutations.

Stem cell collection after lenalidomide, bortezomib and dexamethasone plus elotuzumab or isatuximab in newly diagnosed multiple myeloma patients: a single centre experience from the GMMG-HD6 and -HD7 trials.

BACKGROUND: While quadruplet induction therapies deepen responses in newly diagnosed multiple myeloma patients, their impact on peripheral blood stem cell (PBSC) collection remains incompletely understood. This analysis aims to evaluate the effects of prolonged lenalidomide induction and isatuximab- or elotuzumab-containing quadruplet induction therapies on PBSC mobilization and collection. METHODS: A total of 179 transplant-eligible patients with newly diagnosed MM treated at a single academic center were included. The patients were evaluated based on PBSC mobilization and collection parameters, including overall collection results, CD34+ cell levels in peripheral blood, leukapheresis (LP) delays, overall number of LP sessions, and the rate of rescue mobilization with plerixafor. The patients underwent four different induction regimens: Lenalidomide, bortezomib, and dexamethasone (RVd, six 21-day cycles, n = 44), isatuximab-RVd (six 21-day cycles, n = 35), RVd (four 21-day cycles, n = 51), or elotuzumab-RVd (four 21-day cycles, n = 49). RESULTS: The patients' characteristics were well balanced across the different groups. Collection failures, defined as the inability to collect three sufficient PBSC transplants, were rare (n = 3, 2%), with no occurrences in the isatuximab-RVd and elotuzumab-RVd groups. Intensified induction with six 21-day cycles of RVd did not negatively impact the overall number of collected PBSCs (9.7 × 106/kg bw versus 10.5 × 106/kg bw, p = 0.331) compared to four 21-day cycles of RVd. Plerixafor usage was more common after six cycles of RVd compared to four cycles (16% versus 8%). Addition of elotuzumab to RVd did not adversely affect overall PBSC collection (10.9 × 106/kg bw versus 10.5 × 106/kg bw, p = 0.915). Patients treated with isatuximab-RVd (six cycles) had lower numbers of collected stem cells compared to those receiving RVd (six cycles) induction (8.8 × 106/kg bw versus 9.7 × 106/kg bw, p = 0.801), without experiencing significant delays in LP or increased numbers of LP sessions in a multivariable logistic regression analysis. Plerixafor usage was more common after isatuximab plus RVd compared to RVd alone (34% versus 16%). CONCLUSIONS: This study demonstrates that stem cell collection is feasible after prolonged induction with isatuximab-RVd without collection failures and might be further explored as induction therapy. TRIAL REGISTRATION: Patients were treated within the randomized phase III clinical trials GMMG-HD6 (NCT02495922, 24/06/2015) and GMMG-HD7 (NCT03617731, 24/07/2018). However, during stem cell mobilization and -collection, no study-specific therapeutic intervention was performed.

Cyclophosphamide etoposide dexamethasone as salvage and bridging therapy in relapsed refractory and extramedullary multiple myeloma.

Patients with relapsed refractory multiple myeloma (RRMM) that are triple-exposed to immunomodulatory drugs, proteasome inhibitors, and anti-CD38 monoclonal antibodies have a poor prognosis. Standard treatment for these patients has not been established. Patients with extramedullary disease or secondary plasma cell leukemia often display high tumor cell proliferation and might therefore be susceptible to chemotherapy. While current regimens are often platinum-based, we present single-center data on 70 patients with RRMM who were treated with cyclophosphamide, etoposide, and dexamethasone (CED) after a median of four lines of therapy. An overall response rate of 52% was achieved after 1-6 cycles, with 23% of patients having a very good partial response. Comparable response rates and survival were observed in patients with extramedullary disease and high-risk cytogenetics. Treatment resulted in non-hematological °III-IV adverse events in 31% of patients. No treatment-related deaths occurred. The median progression-free and overall survival were 6.2 and 10.9 months, respectively. 23% of patients were bridged to autologous stem cell transplantation (ASCT) or chimeric antigen receptor (CAR) T cell therapy. In summary, CED is an effective treatment regimen for RRMM cases with a tolerable safety profile and suitable as bridging therapy to CAR T cell treatment and ASCT.

A precision-based exercise program for patients with multiple myeloma.

OBJECTIVES: Aim of this study was to retrospectively evaluate an interdisciplinary consultation followed by a precision-based exercise program (PEP) for myeloma patients with stable and unstable bone lesions. METHODS: Data of myeloma patients (n = 100) who received a PEP according to an orthopedic evaluation were analyzed. Bone stability was assessed by established scoring systems (Spinal Instability Neoplastic Score [SINS], Mirels' score). All patients with stable and unstable osteolyses received a PEP and n = 91 were contacted for a follow-up interview. RESULTS: In 60% of patients at least one osteolysis of the spine was considered potentially unstable or unstable. Following consultation, the number of patients performing resistance training could be significantly increased (≥2 sessions/week, 55%). Musculoskeletal pain was reported frequently. At the follow-up interview, 75% of patients who performed PEP stated that painful symptoms could be effectively alleviated by exercise. Moreover, only patients who exercised regularly discontinued pain medication. No injuries were reported in association with PEP. CONCLUSION: We were able to demonstrate that individualized resistance training is implementable and safe for myeloma patients. By means of a PEP, patients' self-efficacy in managing musculoskeletal pain was enhanced and pain medication could be reduced.

Autologous Stem Cell Collection after Daratumumab, Bortezomib, Thalidomide, and Dexamethasone versus Bortezomib, Cyclophosphamide, and Dexamethasone in Newly Diagnosed Multiple Myeloma.

Introduction: In transplant-eligible, newly diagnosed multiple myeloma (NDMM) patients, autologous peripheral blood stem cell (PBSC) collection is usually pursued after induction therapy. While induction regimens are constantly refined regarding response, their impact on PBSC collection is not fully studied. The inclusion of the anti-CD38 antibody daratumumab into induction therapy significantly improved outcomes for patients with NDMM, e.g., as part of the daratumumab, bortezomib, thalidomide, and dexamethasone (Dara-VTD) protocol. Preliminary data from the phase 3 CASSIOPEIA study proved the efficacy of Dara-VTD. While overall PBSC collection upon addition of daratumumab was reduced in the study population, more detailed analyses on the impact are missing. Methods: We here report on PBSC mobilization and collection metrics in n = 119 patients with NDMM who underwent induction therapy with bortezomib, cyclophosphamide, and dexamethasone (VCD, n = 61) or Dara-VTD (n = 58). Results: Patient characteristics were well balanced between groups. The Dara-VTD group showed improved response parameters with 66% of patients reaching at least very good partial response versus 54% in the VCD group. Dara-VTD patients exhibited inferior mobilization metrics such as peripheral blood CD34+ cell count at the first leukapheresis (LP) session (65 vs. 106/µL, p = 0.001), median number of LP sessions (2 vs. 1, p = 0.001), and PBSC collection at first LP (5.5 vs. 8.3 × 106/kg body weight [bw], p = 0.001). Utilization of plerixafor was slightly higher after Dara-VTD (33% vs. 21% of patients, p = 0.143). The overall PBSC collection result was significantly lower after Dara-VTD (8.4 vs. 9.6 × 106/kg bw, p = 0.026). 78% and 85% of patients successfully collected 3 transplants with ≥2 × 106 CD34+ cells/kg bw in the Dara-VTD and the VCD groups, respectively. Conclusion: In summary, Dara-VTD, possibly due to both anti-CD38 antibody and thalidomide exposure, imposes a limitation on PBSC collection which can be only partly overcome by utilization of plerixafor.

Whole-body magnetic resonance imaging plus serological follow-up for early identification of progression in smouldering myeloma patients to prevent development of end-organ damage.

The definition of multiple myeloma (MM) was updated in 2014, with the intent to enable earlier treatment and thereby avoid appearance of end-organ damage at progression from smouldering multiple myeloma (SMM) to MM. The purpose of this study was to investigate to which extent the development of end-organ damage at progression to MM was reduced under the updated guidelines. In this prospective observational cohort study (ClinicalTrials.gov Identifier: NCT01374412), between 2014 and 2020, 96 SMM patients prospectively underwent whole-body magnetic resonance imaging (wb-MRI) and serological follow-up at baseline and every 6 months thereafter. A total of 22 patients progressed into MM during follow-up, of which seven (32%) showed SLiM-criteria only but no end-organ damage. Four (57%) of the seven patients who progressed by SLiM-criteria only progressed with >1 focal lesion (FL) or a growing FL, and three (43%) due to serum free light-chain-ratio ≥100. Fifteen (68%) out of 22 patients who progressed still suffered from end-organ damage at progression. The updated disease definition reduced the proportion of SMM patients suffering from end-organ damage at progression to MM by one third. wb-MRI is an important tool for detection of SMM patients who progress to MM without end-organ damage.

Oral Selinexor-Dexamethasone for Triple-Class Refractory Multiple Myeloma.

BACKGROUND: Selinexor, a selective inhibitor of nuclear export compound that blocks exportin 1 (XPO1) and forces nuclear accumulation and activation of tumor suppressor proteins, inhibits nuclear factor κB, and reduces oncoprotein messenger RNA translation, is a potential novel treatment for myeloma that is refractory to current therapeutic options. METHODS: We administered oral selinexor (80 mg) plus dexamethasone (20 mg) twice weekly to patients with myeloma who had previous exposure to bortezomib, carfilzomib, lenalidomide, pomalidomide, daratumumab, and an alkylating agent and had disease refractory to at least one proteasome inhibitor, one immunomodulatory agent, and daratumumab (triple-class refractory). The primary end point was overall response, defined as a partial response or better, with response assessed by an independent review committee. Clinical benefit, defined as a minimal response or better, was a secondary end point. RESULTS: A total of 122 patients in the United States and Europe were included in the modified intention-to-treat population (primary analysis), and 123 were included in the safety population. The median age was 65 years, and the median number of previous regimens was 7; a total of 53% of the patients had high-risk cytogenetic abnormalities. A partial response or better was observed in 26% of patients (95% confidence interval, 19 to 35), including two stringent complete responses; 39% of patients had a minimal response or better. The median duration of response was 4.4 months, median progression-free survival was 3.7 months, and median overall survival was 8.6 months. Fatigue, nausea, and decreased appetite were common and were typically grade 1 or 2 (grade 3 events were noted in up to 25% of patients, and no grade 4 events were reported). Thrombocytopenia occurred in 73% of the patients (grade 3 in 25% and grade 4 in 33%). Thrombocytopenia led to bleeding events of grade 3 or higher in 6 patients. CONCLUSIONS: Selinexor-dexamethasone resulted in objective treatment responses in patients with myeloma refractory to currently available therapies. (Funded by Karyopharm Therapeutics; STORM ClinicalTrials.gov number, NCT02336815.).

Comprehensive genomic analysis of refractory multiple myeloma reveals a complex mutational landscape associated with drug resistance and novel therapeutic vulnerabilities.

The outcomes of patients with multiple myeloma (MM) refractory to immunomodulatory agents (IMiDs) and proteasome inhibitors (PIs) remain poor. In this study, we performed whole genome and transcriptome sequencing of 39 heavily pretreated relapsed/refractory MM (RRMM) patients to identify mechanisms of resistance and potential therapeutic targets. We observed a high mutational load and indications of increased genomic instability. Recurrently mutated genes in RRMM, which had not been previously reported or only observed at a lower frequency in newly diagnosed MM, included NRAS, BRAF, TP53, SLC4A7, MLLT4, EWSR1, HCFC2, and COPS3. We found multiple genomic regions with bi-allelic events affecting tumor suppressor genes and demonstrated a significant adverse impact of bi-allelic TP53 alterations on survival. With regard to potentially resistance conferring mutations, recurrently mutated gene networks included genes with relevance for PI and IMiD activity; the latter particularly affecting members of the Cereblon and the COP9 signalosome complex. We observed a major impact of signatures associated with exposure to melphalan or impaired DNA double-strand break homologous recombination repair in RRMM. The latter coincided with mutations in genes associated with PARP inhibitor sensitivity in 49% of RRMM patients; a finding with potential therapeutic implications. In conclusion, this comprehensive genomic characterization revealed a complex mutational and structural landscape in RRMM and highlights potential implications for therapeutic strategies.

Elotuzumab plus Pomalidomide and Dexamethasone for Multiple Myeloma.

BACKGROUND: The immunostimulatory monoclonal antibody elotuzumab plus lenalidomide and dexamethasone has been shown to be effective in patients with relapsed or refractory multiple myeloma. The immunomodulatory agent pomalidomide plus dexamethasone has been shown to be effective in patients with multiple myeloma that is refractory to lenalidomide and a proteasome inhibitor. METHODS: Patients with multiple myeloma that was refractory or relapsed and refractory to lenalidomide and a proteasome inhibitor were randomly assigned to receive elotuzumab plus pomalidomide and dexamethasone (elotuzumab group) or pomalidomide and dexamethasone alone (control group). The primary end point was investigator-assessed progression-free survival. RESULTS: A total of 117 patients were randomly assigned to the elotuzumab group (60 patients) or the control group (57 patients). After a minimum follow-up period of 9.1 months, the median progression-free survival was 10.3 months in the elotuzumab group and 4.7 months in the control group. The hazard ratio for disease progression or death in the elotuzumab group as compared with the control group was 0.54 (95% confidence interval [CI], 0.34 to 0.86; P=0.008). The overall response rate was 53% in the elotuzumab group as compared with 26% in the control group (odds ratio, 3.25; 95% CI, 1.49 to 7.11). The most common grade 3 or 4 adverse events were neutropenia (13% in the elotuzumab group vs. 27% in the control group), anemia (10% vs. 20%), and hyperglycemia (8% vs. 7%). A total of 65% of the patients in each group had infections. Infusion reactions occurred in 3 patients (5%) in the elotuzumab group. CONCLUSIONS: Among patients with multiple myeloma in whom treatment with lenalidomide and a proteasome inhibitor had failed, the risk of progression or death was significantly lower among those who received elotuzumab plus pomalidomide and dexamethasone than among those who received pomalidomide plus dexamethasone alone. (Funded by Bristol-Myers Squibb and AbbVie Biotherapeutics; ELOQUENT-3 ClinicalTrials.gov number, NCT02654132 .).

Novel immunotherapies in multiple myeloma - chances and challenges.

In this review article, we summarize the latest data on antibody-drug conjugates, bispecific T-cell-engaging antibodies, and chimeric antigen receptor T cells in the treatment of multiple myeloma. We discuss the pivotal questions to be addressed as these new immunotherapies become standard agents in the management of multiple myeloma. We also focus on the selection of patients for these therapies and speculate as to how best to individualize treatment approaches. We see these novel immunotherapies as representing a paradigm shift. However, despite the promising preliminary data, many open issues remain to be evaluated in future trials.

Quality of life analyses in patients with multiple myeloma: results from the Selinexor (KPT-330) Treatment of Refractory Myeloma (STORM) phase 2b study.

BACKGROUND: Selinexor is an oral, selective nuclear export inhibitor. STORM was a phase 2b, single-arm, open-label, multicenter trial of selinexor with low dose dexamethasone in patients with penta-exposed relapsed/refractory multiple myeloma (RRMM) that met its primary endpoint, with overall response of 26% (95% confidence interval [CI], 19 to 35%). Health-related quality of life (HRQoL) was a secondary endpoint measured using the Functional Assessment of Cancer Therapy - Multiple Myeloma (FACT-MM). This study examines impact of selinexor treatment on HRQoL of patients treated in STORM and reports two approaches to calculate minimal clinically important differences for the FACT-MM. METHODS: FACT-MM data were collected at baseline, on day 1 of each 4-week treatment cycle, and at end of treatment (EOT). Changes from baseline were analyzed for the FACT-MM total score, FACT-trial outcome index (TOI), FACT-General (FACT-G), and the MM-specific domain using mixed-effects regression models. Two approaches for evaluating minimal clinically important differences were explored: the first defined as 10% of the instrument range, and the second based on estimated mean baseline differences between Eastern Cooperative Oncology Group performance status (ECOG PS) scores. Post-hoc difference analysis compared change in scores from baseline to EOT for treatment responders and non-responders. RESULTS: Eighty patients were included in the analysis; the mean number of prior therapies was 7.9 (standard deviation [SD] 3.1), and mean duration of myeloma was 7.6 years (SD 3.4). Each exploratory minimal clinically important difference threshold yielded consistent results whereby most patients did not experience HRQoL decline during the first six cycles of treatment (range: 53.9 to 75.7% for the first approach; range: 52.6 to 72.9% for the second). Treatment responders experienced less decline in HRQoL from baseline to EOT than non-responders, which was significant for the FACT-G, but not for other scores. CONCLUSION: The majority of patients did not experience decline in HRQoL based on minimal clinically important differences during early cycles of treatment with selinexor and dexamethasone in the STORM trial. An anchor-based approach utilizing patient-level data (ECOG PS score) to define minimal clinically important differences for the FACT-MM gave consistent results with a distribution-based approach. TRIAL REGISTRATION: This trial was registered on ClinicalTrials.gov under the trial-ID NCT02336815 on January 8, 2015.

B-cell maturation antigen-specific chimeric antigen receptor T cells for multiple myeloma: Clinical experience and future perspectives.

Despite major advances in the treatment of multiple myeloma (MM), it remains a largely incurable disease with long-term control often dependent on continuous therapy. More effective, better tolerated treatments are therefore required to achieve durable remissions and to improve the quality of life of MM patients. Adoptive immunotherapy employing T cells expressing chimeric antigen receptors (CAR) is currently among the most promising treatment approaches in cancer. Within the target portfolio for MM immunotherapy, B-cell maturation antigen (BCMA) is among the most widely studied target antigens. BCMA is consistently expressed on MM cells and, importantly, is not expressed in critical healthy tissue. For this reason, it is an ideal target for MM immunotherapy. Several clinical trials evaluating different BCMA-targeting CAR constructs have been initiated and early results are very promising. However, in this rapidly developing clinical landscape, the ultimate role of BCMA-specific CAR-T cell therapy remains unclear. In this review, we will summarize currently available clinical data on BCMA-directed CAR-T cells and discuss potential future perspective for this promising treatment approach in MM.