An IL-1ß-driven neutrophil-stromal cell axis fosters a BAFF-rich protumor microenvironment in individuals with multiple myeloma.

Human bone marrow permanently harbors high numbers of neutrophils, and a tumor-supportive bias of these cells could significantly impact bone marrow-confined malignancies. In individuals with multiple myeloma, the bone marrow is characterized by inflammatory stromal cells with the potential to influence neutrophils. We investigated myeloma-associated alterations in human marrow neutrophils and the impact of stromal inflammation on neutrophil function. Mature neutrophils in myeloma marrow are activated and tumor supportive and transcribe increased levels of IL1B and myeloma cell survival factor TNFSF13B (BAFF). Interactions with inflammatory stromal cells induce neutrophil activation, including BAFF secretion, in a STAT3-dependent manner, and once activated, neutrophils gain the ability to reciprocally induce stromal activation. After first-line myeloid-depleting antimyeloma treatment, human bone marrow retains residual stromal inflammation, and newly formed neutrophils are reactivated. Combined, we identify a neutrophil-stromal cell feed-forward loop driving tumor-supportive inflammation that persists after treatment and warrants novel strategies to target both stromal and immune microenvironments in multiple myeloma.

Update and European consensus on a patient-centered core outcome set for multiple myeloma in clinical practice and research.

Not available.

Daratumumab, Bortezomib, Lenalidomide, and Dexamethasone for Multiple Myeloma.

BACKGROUND: Daratumumab, a monoclonal antibody targeting CD38, has been approved for use with standard myeloma regimens. An evaluation of subcutaneous daratumumab combined with bortezomib, lenalidomide, and dexamethasone (VRd) for the treatment of transplantation-eligible patients with newly diagnosed multiple myeloma is needed. METHODS: In this phase 3 trial, we randomly assigned 709 transplantation-eligible patients with newly diagnosed multiple myeloma to receive either subcutaneous daratumumab combined with VRd induction and consolidation therapy and with lenalidomide maintenance therapy (D-VRd group) or VRd induction and consolidation therapy and lenalidomide maintenance therapy alone (VRd group). The primary end point was progression-free survival. Key secondary end points were a complete response or better and minimal residual disease (MRD)-negative status. RESULTS: At a median follow-up of 47.5 months, the risk of disease progression or death in the D-VRd group was lower than the risk in the VRd group. The estimated percentage of patients with progression-free survival at 48 months was 84.3% in the D-VRd group and 67.7% in the VRd group (hazard ratio for disease progression or death, 0.42; 95% confidence interval, 0.30 to 0.59; P<0.001); the P value crossed the prespecified stopping boundary (P = 0.0126). The percentage of patients with a complete response or better was higher in the D-VRd group than in the VRd group (87.9% vs. 70.1%, P<0.001), as was the percentage of patients with MRD-negative status (75.2% vs. 47.5%, P<0.001). Death occurred in 34 patients in the D-VRd group and 44 patients in the VRd group. Grade 3 or 4 adverse events occurred in most patients in both groups; the most common were neutropenia (62.1% with D-VRd and 51.0% with VRd) and thrombocytopenia (29.1% and 17.3%, respectively). Serious adverse events occurred in 57.0% of the patients in the D-VRd group and 49.3% of those in the VRd group. CONCLUSIONS: The addition of subcutaneous daratumumab to VRd induction and consolidation therapy and to lenalidomide maintenance therapy conferred a significant benefit with respect to progression-free survival among transplantation-eligible patients with newly diagnosed multiple myeloma. (Funded by the European Myeloma Network in collaboration with Janssen Research and Development; PERSEUS ClinicalTrials.gov number, NCT03710603; EudraCT number, 2018-002992-16.).

Difficult-to-treat patients with relapsed/refractory multiple myeloma: A review of clinical trial results.

Overall outcomes for multiple myeloma have improved due to the availability of new therapies, but patients with relapsed/refractory multiple myeloma harbouring certain factors continue to pose a therapeutic challenge. These challenging features include high-risk cytogenetics, renal impairment, patient characteristics such as age and frailty, and extramedullary disease. Prior refractory status and number of prior lines add further complexity to the treatment of these patients. While newer regimens are available and have suggested efficacy in these patient populations through subgroup analyses, differences in trial definitions and cut-offs make meaningful comparisons difficult. This review aims to examine the available clinical trial data for patients with high-risk cytogenetics, renal impairment, age and frailty and extramedullary disease.

Treatment of primary plasma cell leukaemia with carfilzomib and lenalidomide-based therapy (EMN12/HOVON-129): final analysis of a non-randomised, multicentre, phase 2 study.

BACKGROUND: Primary plasma cell leukaemia is a rare and aggressive plasma cell disorder with a poor prognosis. The aim of the EMN12/HOVON-129 study was to improve the outcomes of patients with primary plasma cell leukaemia by incorporating carfilzomib and lenalidomide in induction, consolidation, and maintenance therapy. METHODS: The EMN12/HOVON-129 study is a non-randomised, phase 2, multicentre study conducted at 19 academic centres and hospitals in seven European countries (Belgium, Czech Republic, Denmark, Italy, Norway, The Netherlands, and the UK) for previously untreated patients with primary plasma cell leukaemia aged 18 years or older. Inclusion criteria were newly diagnosed primary plasma cell leukaemia (defined as >2 ×109 cells per L circulating monoclonal plasma cells or plasmacytosis >20% of the differential white cell count) and WHO performance status 0-3. Patients aged 18-65 years (younger patients) and 66 years or older (older patients) were treated in age-specific cohorts and were analysed separately. Younger patients were treated with four 28-day cycles of carfilzomib (36 mg/m2 intravenously on days 1, 2, 8, 9, 15, and 16), lenalidomide (25 mg orally on days 1-21), and dexamethasone (20 mg orally on days 1, 2, 8, 9, 15, 16, 22, and 23). Carfilzomib-lenalidomide-dexamethasone (KRd) induction was followed by double autologous haematopoietic stem-cell transplantation (HSCT), four cycles of KRd consolidation, and then maintenance with carfilzomib (27 mg/m2 intravenously on days 1, 2, 15, and 16 for the first 12 28-day cycles, and then 56 mg/m2 on days 1 and 15 in all subsequent cycles) and lenalidomide (10 mg orally on days 1-21) until progression. Patients who were eligible for allogeneic HSCT, could also receive a single autologous HSCT followed by reduced-intensity conditioning allogeneic HSCT and then carfilzomib-lenalidomide maintenance. Older patients received eight cycles of KRd induction followed by maintenance therapy with carfilzomib and lenalidomide until progression. The primary endpoint was progression-free survival. The primary analysis population was the intention-to-treat population, irrespective of the actual treatment received. Data from all participants who received any study drug were included in the safety analyses. The trial was registered at www.trialregister.nl (until June 2022) and https://trialsearch.who.int/ as NTR5350; recruitment is complete and this is the final analysis. FINDINGS: Between Oct 23, 2015, and Aug 5, 2021, 61 patients were enrolled and received KRd induction treatment (36 patients aged 18-65 years [20 (56%) were male and 16 (44%) female], and 25 aged ≥66 years [12 (48%) were male and 13 (52%) female]). With a median follow-up of 43·5 months (IQR 27·7-67·8), the median progression-free survival was 15·5 months (95% CI 9·4-38·4) for younger patients. For older patients, median follow-up was 32·0 months (IQR 24·7-34·6), and median progression-free survival was 13·8 months (95% CI 9·2-35·5). Adverse events were most frequently observed directly after treatment initiation, with infections (two of 36 (6%) younger patients and eight of 25 (32%) older patients) and respiratory events (two of 36 [6%] younger patients and four of 25 [16%] older patients) being the most common grade 3 or greater events during the first four KRd cycles. Treatment-related serious adverse events were reported in 26 (72%) of 36 younger patients and in 19 (76%) of 25 older patients, with infections being the most common. Treatment-related deaths were reported in none of the younger patients and three (12%) of the older patients (two infections and one unknown cause of death). INTERPRETATION: Carfilzomib and lenalidomide-based therapy provides improved progression-free survival compared with previously published data. However, results remain inferior in primary plasma cell leukaemia compared with multiple myeloma, highlighting the need for new studies incorporating novel immunotherapies. FUNDING: Dutch Cancer Society, Celgene (a BMS company), and AMGEN.

Prevention and management of adverse events during treatment with bispecific antibodies and CAR T cells in multiple myeloma: a consensus report of the European Myeloma Network.

T-cell redirecting bispecific antibodies (BsAbs) and chimeric antigen receptor T cells (CAR T cells) have revolutionised multiple myeloma therapy, but adverse events such as cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome (ICANS), cytopenias, hypogammaglobulinaemia, and infections are common. This Policy Review presents a consensus from the European Myeloma Network on the prevention and management of these adverse events. Recommended measures include premedication, frequent assessing for symptoms and severity of cytokine release syndrome, step-up dosing for several BsAbs and some CAR T-cell therapies; corticosteroids; and tocilizumab in the case of cytokine release syndrome. Other anti-IL-6 drugs, high-dose corticosteroids, and anakinra might be considered in refractory cases. ICANS often arises concomitantly with cytokine release syndrome. Glucocorticosteroids in increasing doses are recommended if needed, as well as anakinra if the response is inadequate, and anticonvulsants if convulsions occur. Preventive measures against infections include antiviral and antibacterial drugs and administration of immunoglobulins. Treatment of infections and other complications is also addressed.

NK Cell Phenotype Is Associated With Response and Resistance to Daratumumab in Relapsed/Refractory Multiple Myeloma.

The CD38-targeting antibody daratumumab has marked activity in multiple myeloma (MM). Natural killer (NK) cells play an important role during daratumumab therapy by mediating antibody-dependent cellular cytotoxicity via their FcγRIII receptor (CD16), but they are also rapidly decreased following initiation of daratumumab treatment. We characterized the NK cell phenotype at baseline and during daratumumab monotherapy by flow cytometry and cytometry by time of flight to assess its impact on response and development of resistance (DARA-ATRA study; NCT02751255). At baseline, nonresponding patients had a significantly lower proportion of CD16+ and granzyme B+ NK cells, and higher frequency of TIM-3+ and HLA-DR+ NK cells, consistent with a more activated/exhausted phenotype. These NK cell characteristics were also predictive of inferior progression-free survival and overall survival. Upon initiation of daratumumab treatment, NK cells were rapidly depleted. Persisting NK cells exhibited an activated and exhausted phenotype with reduced expression of CD16 and granzyme B, and increased expression of TIM-3 and HLA-DR. We observed that addition of healthy donor-derived purified NK cells to BM samples from patients with either primary or acquired daratumumab-resistance improved daratumumab-mediated MM cell killing. In conclusion, NK cell dysfunction plays a role in primary and acquired daratumumab resistance. This study supports the clinical evaluation of daratumumab combined with adoptive transfer of NK cells.

Improving Outcome-Driven Care in Multiple Myeloma Using Patient-Reported Outcomes: A Qualitative Evaluation Study.

BACKGROUND AND OBJECTIVE: Multiple myeloma is an incurable disease with a considerable illness and treatment burden, which negatively impacts patients' quality of life. This study aimed to evaluate the implementation of multiple myeloma care in five Dutch hospitals, related to the three objectives of outcome-driven care, which are defined as (1) providing information for shared decision making in individual patient care, (2) supporting the learning capacity of healthcare professionals and healthcare institutions through benchmarking and (3) developing outcome-driven and patient-centred contracting by health insurers. METHODS: In this qualitative study, semi-structured interviews about experiences with patient-reported outcomes were conducted with patients, healthcare professionals and other stakeholders 2 years after implementation. Data were thematically analysed, and emerging topics were clustered around the three objectives of outcome-driven care. RESULTS: A total of 46 interviews were held (15 with patients, 16 with professionals and 15 with other stakeholders) that showed patients with multiple myeloma were willing to complete patient-reported outcomes, although integration of patient-reported outcomes in shared decision making fell short in clinical practice. Aggregated patient-reported outcomes were considered important for improving quality of care; however, data collection and data exchange are hindered by privacy legislation, limitations of IT systems and a lack of data standards. Patient-reported outcomes were expected to contribute to cost-effective multiple myeloma treatment, yet outcome-driven reimbursement is still lacking. CONCLUSIONS: Outcome-driven multiple myeloma care using patient-reported outcomes is feasible, provided that (1) patient-reported outcomes and shared decision making are integrated into clinical practice, (2) legal and technical obstacles hindering data collection are removed and (3) health insurers adjust their reimbursement plans to facilitate outcome-driven care.

Carfilzomib, Pomalidomide, and Dexamethasone As Second-line Therapy for Lenalidomide-refractory Multiple Myeloma.

This phase 2 trial investigated reinduction with carfilzomib, pomalidomide, and dexamethasone (KPd) and continuous pomalidomide/dexamethasone in patients at first progression during lenalidomide maintenance. The second objective was to evaluate high-dose melphalan with autologous stem cell transplantation (HDM/ASCT) at first progression. Patients were eligible who had progressive disease according to International Myeloma Working Group (IMWG) criteria. Treatment consisted of 8 cycles carfilzomib (20/36 mg/m2), pomalidomide (4 mg) and dexamethasone. Patients without prior transplant received HDM/ASCT. Pomalidomide 4 mg w/o dexamethasone was given until progression. One hundred twelve patients were registered of whom 86 (77%) completed 8 cycles of KPd. Thirty-five (85%) eligible patients received HDM/ASCT. The median time to discontinuation of pomalidomide w/o dexamethasone was 17 months. Best response was 37% ≥ complete response, 75% ≥ very good partial response, 92% ≥ partial response, respectively. At a follow-up of 40 months median PFS was 26 and 32 months for patients who received KPd plus HDM/ASCT and 17 months for patients on KPd (hazard ratio [HR] 0.61, 95% confidence interval [CI] 0.37-1.00, P = 0.051). PFS was better after longer duration of prior lenalidomide (HR 3.56, 95% CI 1.42-8.96, P = 0.035). Median overall survival (OS) was 67 months. KPd-emerging grade 3 and 4 adverse events included hematologic (41%), cardiovascular (6%), respiratory (3%), infections (17%), and neuropathy (2%). KPd followed by continuous pomalidomide is an effective and safe triple drug regimen in second-line for patients previously exposed to bortezomib and/or refractory to lenalidomide.

Identification of High-Risk Multiple Myeloma With a Plasma Cell Leukemia-Like Transcriptomic Profile.

PURPOSE: Primary plasma cell leukemia (pPCL) is an aggressive subtype of multiple myeloma, which is distinguished from newly diagnosed multiple myeloma (NDMM) on the basis of the presence of ≥ 20% circulating tumor cells (CTCs). A molecular marker for pPCL is currently lacking, which could help identify NDMM patients with high-risk PCL-like disease, despite not having been recognized as such clinically. METHODS: A transcriptomic classifier for PCL-like disease was bioinformatically constructed and validated by leveraging information on baseline CTC levels, tumor burden, and tumor transcriptomics from 154 patients with NDMM included in the Cassiopeia or HO143 trials and 29 patients with pPCL from the EMN12/HO129 trial. Its prognostic value was assessed in an independent cohort of 2,139 patients with NDMM from the HOVON-65/GMMG-HD4, HOVON-87/NMSG-18, EMN02/HO95, MRC-IX, Total Therapy 2, Total Therapy 3, and MMRF CoMMpass studies. RESULTS: High CTC levels were associated with the expression of 1,700 genes, independent of tumor burden (false discovery rate < 0.05). Of these, 54 genes were selected by leave-one-out cross-validation to construct a transcriptomic classifier representing PCL-like disease. This not only demonstrated a sensitivity of 93% to identify pPCL in the validation cohort but also classified 10% of NDMM tumors as PCL-like. PCL-like MM transcriptionally and cytogenetically resembled pPCL, but presented with significantly lower CTC levels and tumor burden. Multivariate analyses in NDMM confirmed the significant prognostic value of PCL-like status in the context of Revised International Staging System stage, age, and treatment, regarding both progression-free (hazard ratio, 1.64; 95% CI, 1.30 to 2.07) and overall survival (hazard ratio, 1.89; 95% CI, 1.42 to 2.50). CONCLUSION: pPCL was identified on the basis of a specific tumor transcriptome, which was also present in patients with high-risk NDMM, despite not being clinically leukemic. Incorporating PCL-like status into current risk models in NDMM may improve prognostic accuracy.

LocoMMotion: a prospective, non-interventional, multinational study of real-life current standards of care in patients with relapsed and/or refractory multiple myeloma.

Despite treatment advances, patients with multiple myeloma (MM) often progress through standard drug classes including proteasome inhibitors (PIs), immunomodulatory drugs (IMiDs), and anti-CD38 monoclonal antibodies (mAbs). LocoMMotion (ClinicalTrials.gov identifier: NCT04035226) is the first prospective study of real-life standard of care (SOC) in triple-class exposed (received at least a PI, IMiD, and anti-CD38 mAb) patients with relapsed/refractory MM (RRMM). Patients (N = 248; ECOG performance status of 0-1, ≥3 prior lines of therapy or double refractory to a PI and IMiD) were treated with median 4.0 (range, 1-20) cycles of SOC therapy. Overall response rate was 29.8% (95% CI: 24.2-36.0). Median progression-free survival (PFS) and median overall survival (OS) were 4.6 (95% CI: 3.9-5.6) and 12.4 months (95% CI: 10.3-NE). Treatment-emergent adverse events (TEAEs) were reported in 83.5% of patients (52.8% grade 3/4). Altogether, 107 deaths occurred, due to progressive disease (n = 74), TEAEs (n = 19), and other reasons (n = 14). The 92 varied regimens utilized demonstrate a lack of clear SOC for heavily pretreated, triple-class exposed patients with RRMM in real-world practice and result in poor outcomes. This supports a need for new treatments with novel mechanisms of action.

Pomalidomide in Patients With Relapsed and/or Refractory Multiple Myeloma: A Prospective Study Within the Nationwide Netherlands Cancer Registry.

Patients with relapsed and/or refractory multiple myeloma (RRMM) generally have limited treatment options and a poor prognosis. Previous trials demonstrated that pomalidomide combined with low-dose dexamethasone (Pd) is effective in these patients with significant responses and improved progression-free survival (PFS). Pd has been approved in RRMM patients who received ≥2 prior lines of therapy. Here, we present the results of a population-based study of patients with RRMM treated with Pd in The Netherlands from time of pomalidomide approval. Using the nationwide Netherlands Cancer Registry, data from all nontrial patients with RRMM treated with Pd were collected. Data were analyzed of response, PFS, and overall survival (OS). A total of 237 patients were included in this analysis. Previous treatment consisted of a proteasome inhibitor in 227 patients (96%) and/or an immune-modulating agent in 235 patients (99%). One hundred forty patients (59%) were refractory to an immune-modulating agent in their last line of therapy. Median time from diagnosis to treatment with Pd was 4.9 years (interquartile range, 2.7-7.9), and the median number of prior treatments was 4 (interquartile range, 3-5). Median PFS and OS for all patients were 3.6 months (95% confidence interval [CI], 3.1-3.8) and 7.7 months (95% CI, 5.7-9.7), respectively. For patients achieving ≥PR, median PFS and OS were 10.6 months (95% CI, 8.3-12.9) and 16.3 months (95% CI, 13.6-23.2), respectively. This nationwide, population-based registry study confirms data shown in pivotal clinical trials on Pd. PFS in this analysis is comparable to PFS observed in those clinical trials.

VS38c and CD38-Multiepitope Antibodies Provide Highly Comparable Minimal Residual Disease Data in Patients With Multiple Myeloma.

OBJECTIVES: To compare flow cytometric minimal residual disease (MRD) data obtained using the EuroFlow approach, including the CD38-multiepitope (ME) antibody or the VS38c antibody. METHODS: We evaluated 29 bone marrow samples from patients with multiple myeloma (MM), of whom 15 had received daratumumab within the past 6 months. We evaluated MRD data and fluorescence intensities. RESULTS: Qualitative MRD data were 100% concordant between the 2 approaches. In MRD-positive samples (n = 14), MRD levels showed an excellent correlation (R2 = 0.999). Whereas VS38c staining was strong in both normal plasma cells and MM cells, independent of daratumumab treatment, staining intensities for CD38 were lower in MM cells compared with normal plasma cells, and on both cell types CD38 expression was significantly reduced in daratumumab-treated patients. CONCLUSIONS: Both CD38-ME and VS38c allow reliable MRD detection in MM patients, but the high expression of VS38c allows easier identification of MM cells, especially in daratumumab-treated patients.

Decrease in early mortality for newly diagnosed multiple myeloma patients in the Netherlands: a population-based study.

Identification of risk factors for early mortality (EM) in multiple myeloma (MM) patients may contribute to different therapeutic approaches in patients at risk for EM. This population-based study aimed to assess trends in EM and risk factors for EM among MM patients diagnosed in the Netherlands. All MM patients, newly diagnosed between 1989 and 2018, were identified in the Netherlands Cancer Registry. Patients were categorized into three calendar periods (1989-1998, 1999-2008, 2009-2018) and into five age groups (≤65, 66-70, 71-75, 76-80, >80 years). EM was defined as death by any cause ≤180 days post-diagnosis. We included 28,328 MM patients (median age 70 years; 55% males). EM decreased from 22% for patients diagnosed in 1989-1998 to 13% for patients diagnosed in 2009-2018 (P < 0.01) and this decrease was observed among all age groups. Exact causes of death could not be elucidated. Besides patient's age, we found that features related to a more aggressive disease presentation, and patient characteristics reflecting patients' physical condition were predictive of EM. In summary, EM decreased from 1999 onwards. Nevertheless, EM remains high, especially for patients aged >70 years. Therefore, novel strategies should be explored to improve the outcome of patients at risk for EM.

COVID-19 vaccination in patients with multiple myeloma: a consensus of the European Myeloma Network.

Patients with multiple myeloma frequently present with substantial immune impairment and an increased risk for infections and infection-related mortality. The risk for infection with SARS-CoV-2 virus and resulting mortality is also increased, emphasising the importance of protecting patients by vaccination. Available data in patients with multiple myeloma suggest a suboptimal anti-SARS-CoV-2 immune response, meaning a proportion of patients are unprotected. Factors associated with poor response are uncontrolled disease, immunosuppression, concomitant therapy, more lines of therapy, and CD38 antibody-directed and B-cell maturation antigen-directed therapy. These facts suggest that monitoring the immune response to vaccination in patients with multiple myeloma might provide guidance for clinical management, such as administration of additional doses of the same or another vaccine, or even temporary treatment discontinuation, if possible. In those who do not exhibit a good response, prophylactic treatment with neutralising monoclonal antibody cocktails might be considered. In patients deficient of a SARS-CoV-2 immune response, adherence to measures for infection risk reduction is particularly recommended. This consensus was generated by members of the European Multiple Myeloma Network and some external experts. The panel members convened in virtual meetings and conducted an extensive literature research and evaluated recently published data and work presented at meetings, as well as findings from their own studies. The outcome of the discussions on establishing consensus recommendations for COVID-19 vaccination in patients with multiple myeloma was condensed into this Review.

Efficacy and safety of daratumumab combined with all-trans retinoic acid in relapsed/refractory multiple myeloma.

The efficacy of daratumumab depends partially on CD38 expression on multiple myeloma (MM) cells. We have previously shown that all-trans retinoic acid (ATRA) upregulates CD38 expression and reverts daratumumab-resistance ex vivo. We therefore evaluated the optimal dose, efficacy, and safety of daratumumab combined with ATRA in patients with daratumumab-refractory MM in a phase 1/2 study (NCT02751255). In part A of the study, 63 patients were treated with daratumumab monotherapy. Fifty patients with daratumumab-refractory MM were subsequently enrolled in part B and treated with daratumumab (reintensified schedule) combined with ATRA until disease progression. The recommended phase 2 dose of ATRA in combination with daratumumab was defined as 45 mg/m2. At this dose, the overall response rate (ORR) was 5%, indicating that the primary endpoint (ORR ≥15%) was not met. However, most patients (66%) achieved at least stable disease. After a median follow-up of 43 months, the median progression-free survival (PFS) for all patients was 2.8 months. Patients who previously achieved at least a partial response or minimal response/stable disease with prior daratumumab monotherapy had a significantly longer PFS compared with patients who immediately progressed during daratumumab as single agent (median PFS 3.4 and 2.8 vs 1.3 months). The median overall survival was 19.1 months. The addition of ATRA did not increase the incidence of adverse events. Flow cytometric analysis revealed that ATRA temporarily increased CD38 expression on immune cell subsets. In conclusion, the addition of ATRA and reintensification of daratumumab had limited activity in patients with daratumumab-refractory MM, which may be explained by the transient upregulation of CD38 expression. This trial was registered at www.clinicaltrials.gov as #NCT02751255.

Maintenance with daratumumab or observation following treatment with bortezomib, thalidomide, and dexamethasone with or without daratumumab and autologous stem-cell transplant in patients with newly diagnosed multiple myeloma (CASSIOPEIA): an open-label, randomised, phase 3 trial.

BACKGROUND: CASSIOPEIA part 1 showed superior depth of response and significantly improved progression-free survival with daratumumab, bortezomib, thalidomide, and dexamethasone (D-VTd) versus bortezomib, thalidomide, and dexamethasone (VTd) as induction and consolidation in patients with autologous stem-cell transplant (ASCT)-eligible newly diagnosed multiple myeloma. In part 2, we compared daratumumab maintenance versus observation only. METHODS: CASSIOPEIA is a two-part, open-label, randomised, phase 3 trial of patients aged 18-65 years with newly diagnosed multiple myeloma and Eastern Cooperative Oncology Group performance status 0-2, done in 111 European academic and community practice centres. In part 1, patients were randomly assigned (1:1) to induction and consolidation with D-VTd or VTd. Patients still on study who had a partial response or better were randomly assigned (1:1) by an interactive web-response system to daratumumab 16 mg/kg intravenously every 8 weeks (a reduced frequency compared with standard daratumumab long-term dosing) or observation only for up to 2 years. Stratification factors were induction treatment and depth of response in part 1. The part 2 primary endpoint was progression-free survival from second randomisation. This preplanned interim analysis of progression-free survival was done after 281 events and shall be considered the primary analysis of progression-free survival. Sponsor personnel and designees who were involved in the analysis were masked to treatment group until the independent data monitoring committee recommended that the preplanned interim analysis be considered the main analysis of progression-free survival in part 2. Otherwise, treatment assignments were unmasked. The interaction between induction and consolidation and maintenance was tested at a two-sided significance level of 0·05 by a stratified Cox regression model that included the interaction term between maintenance treatment and induction and consolidation treatment. Efficacy analyses were done in the maintenance-specific intention-to-treat population, which comprised all patients who underwent second randomisation. Safety was analysed in all patients in the daratumumab group who received at least one dose and all patients randomly assigned to observation only. This trial is registered with ClinicalTrials.gov, NCT02541383. Long-term follow-up is ongoing and the trial is closed to new participants. FINDINGS: Between May 30, 2016, and June 18, 2018, 886 patients (458 [84%] of 543 in the D-VTd group and 428 [79%] of 542 in the VTd group) were randomly assigned to daratumumab maintenance (n=442) or observation only (n=444). At a median follow-up of 35·4 months (IQR 30·2-39·9) from second randomisation, median progression-free survival was not reached (95% CI not evaluable [NE]-NE) with daratumumab versus 46·7 months (40·0-NE) with observation only (hazard ratio 0·53, 95% CI 0·42-0·68, p<0·0001). A prespecified analysis of progression-free survival results showed a significant interaction between maintenance and induction and consolidation therapy (p<0·0001). The most common grade 3 or 4 adverse events were lymphopenia (16 [4%] of 440 patients in the daratumumab group vs eight [2%] of 444 patients in the observation-only group), hypertension (13 [3%] vs seven [2%]), and neutropenia (nine [2%] vs ten [2%]). Serious adverse events occurred in 100 (23%) patients in the daratumumab group and 84 (19%) patients in the observation-only group. In the daratumumab group, two adverse events led to death (septic shock and natural killer-cell lymphoblastic lymphoma); both were related to treatment. INTERPRETATION: Daratumumab maintenance every 8 weeks for 2 years significantly reduced the risk of disease progression or death compared with observation only. Longer follow-up and other ongoing studies will shed further light on the optimal daratumumab-containing post-ASCT maintenance treatment strategy. FUNDING: Janssen Research & Development, the Intergroupe Francophone du Myélome, and the Dutch-Belgian Cooperative Trial Group for Hematology Oncology.