Remission and Progression-Free Survival in Patients With Newly Diagnosed Multiple Myeloma Treated With Carfilzomib, Lenalidomide, and Dexamethasone: Five-Year Follow-up of a Phase 2 Clinical Trial

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

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

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.

Bortezomib, lenalidomide and dexamethasone (VRd) vs carfilzomib, lenalidomide and dexamethasone (KRd) as induction therapy in newly diagnosed multiple myeloma

Lenalidomide and dexamethasone with bortezomib (VRd) or carfilzomib (KRd) are commonly used induction regimens in the U.S. This single-center, retrospective study evaluated outcomes and safety of VRd and KRd. Primary endpoint was progression-free survival (PFS). Of 389 patients with newly diagnosed multiple myeloma, 198 received VRd and 191 received KRd. Median PFS was not reached (NR) in both groups; 5-year PFS was 56% (95%CI, 48-64%) for VRd and 67% (60-75%) for KRd (P = 0.027). Estimated 5-year EFS was 34% (95%CI, 27-42%) for VRd and 52% (45-60%) for KRd (P < 0.001) with corresponding 5-year OS of 80% (95%CI, 75-87%) and 90% (85-95%), respectively (P = 0.053). For standard-risk patients, 5-year PFS was 68% (95%CI, 60-78%) for VRd and 75% (65-85%) for KRd (P = 0.20) with 5-year OS of 87% (95%CI, 81-94%) and 93% (87-99%), respectively (P = 0.13). For high-risk patients, median PFS was 41 months (95%CI, 32.8-61.1) for VRd and 70.9 months (58.2-NR) for KRd (P = 0.016). Respective 5-year PFS and OS were 35% (95%CI, 24-51%) and 69% (58-82%) for VRd and 58% (47-71%) and 88% (80-97%, P = 0.044) for KRd. Overall, KRd resulted in improved PFS and EFS with a trend toward improved OS compared to VRd with associations primarily driven by improvements in outcome for high-risk patients.

Bortezomib, Lenalidomide and Dexamethasone (VRd) vs Carfilzomib, Lenalidomide and Dexamethasone (KRd) as Induction Therapy in Newly Diagnosed Multiple Myeloma

Lenalidomide and dexamethasone with bortezomib (VRd) or carfilzomib (KRd) are commonly used induction regimens in the U.S. This single-center, retrospective study evaluated outcomes and safety of VRd and KRd. Primary endpoint was progression-free survival (PFS). Of 389 patients with newly diagnosed multiple myeloma, 198 received VRd and 191 received KRd. Median PFS was not reached (NR) in both groups; 5-year PFS was 56% (95%CI, 48%-64%) for VRd and 67% (60%-75%) for KRd (P = 0.027). Estimated 5-year EFS was 34% (95%CI, 27%-42%) for VRd and 52% (45%-60%) for KRd (P < 0.001) with corresponding 5-year OS of 80% (95%CI, 75%-87%) and 90% (85%-95%), respectively (P = 0.053). For standard-risk patients, 5-year PFS was 68% (95%CI, 60%-78%) for VRd and 75% (65%-85%) for KRd (P = 0.20) with 5-year OS of 87% (95%CI, 81%-94%) and 93% (87%-99%), respectively (P = 0.13). For high-risk patients, median PFS was 41 months (95%CI, 32.8-61.1) for VRd and 70.9 months (58.2-NR) for KRd (P = 0.016). Respective 5-year PFS and OS were 35% (95%CI, 24%-51%) and 69% (58%-82%) for VRd and 58% (47%-71%) and 88% (80%-97%, P = 0.044) for KRd. Overall, KRd resulted in improved PFS and EFS with a trend toward improved OS compared to VRd with associations primarily driven by improvements in outcome for high-risk patients.

Elotuzumab and Weekly Carfilzomib, Lenalidomide, and Dexamethasone in Patients With Newly Diagnosed Multiple Myeloma Without Transplant Intent: A Phase 2 Measurable Residual Disease-Adapted Study

Importance

Treatment of newly diagnosed multiple myeloma (NDMM) with a quadruplet regimen consisting of a monoclonal antibody, proteasome inhibitor, immunomodulatory imide, and corticosteroid has been associated with improved progression-free survival (PFS) compared with triplet regimens. The optimal quadruplet combination, and whether this obviates the need for frontline autologous stem cell transplant (ASCT), remains unknown. We evaluated elotuzumab and weekly carfilzomib, lenalidomide, and dexamethasone (Elo-KRd) without ASCT in NDMM.

Objective

To investigate the efficacy of Elo-KRd using a measurable residual disease (MRD)-adapted design in NDMM regardless of ASCT eligibility.

Design, Setting, and Participants

This multicenter, single-arm, phase 2 study enrolled patients between July 2017 and February 2021. Median follow-up was 29 months.

Interventions

Twelve to 24 cycles of Elo-KRd; consecutive MRD-negative results at 10-6 by next-generation sequencing (NGS) after cycles 8 (C8) and 12 determined the duration of Elo-KRd. This was followed by Elo-Rd (no carfilzomib) maintenance therapy until disease progression.

Main Outcomes and Measures

The primary end point was the rate of stringent complete response (sCR) and/or MRD-negativity (10-5) after C8 Elo-KRd. Secondary end points included safety, rate of response, MRD status, PFS, and overall survival (OS). As an exploratory analysis, MRD was assessed using liquid chromatography mass spectrometry (MS) on peripheral blood samples.

Results

Forty-six patients were enrolled (median age 62 years, 11 [24%] aged >70 years). Overall, 32 (70%) were White, 6 (13%) were Black, 3 (6%) were more than 1 race, and 5 (11%) were of unknown race. Thirty-three (72%) were men and 13 (28%) were women. High-risk cytogenetic abnormalities were present in 22 (48%) patients. The rate of sCR and/or MRD-negativity after C8 was 26 of 45 (58%), meeting the predefined statistical threshold for efficacy. Responses deepened over time, with the MRD-negativity (10-5) rate increasing to 70% and MS-negativity rate increasing to 65%; concordance between MRD by NGS and MS increased over time. The most common (>10%) grade 3 or 4 adverse events were lung and nonpulmonary infections (13% and 11%, respectively). There was 1 grade 5 myocardial infarction. The estimated 3-year PFS was 72% overall and 92% for patients with MRD-negativity (10-5) at C8.

Conclusions and Relevance

An MRD-adapted design using elotuzumab and weekly KRd without ASCT showed a high rate of sCR and/or MRD-negativity and durable responses. This approach provides support for further evaluation of MRD-guided deescalation of therapy to decrease treatment exposure while sustaining deep responses.

Trial Registration

ClinicalTrials.gov Identifier: NCT02969837.

Perspectives on the Risk-Stratified Treatment of Multiple Myeloma

The multiple myeloma treatment landscape has changed dramatically. This change, paralleled by an increase in scientific knowledge, has resulted in significant improvement in survival. However, heterogeneity remains in clinical outcomes, with a proportion of patients not benefiting from current approaches and continuing to have a poor prognosis. A significant proportion of the variability in outcome can be predicted on the basis of clinical and biochemical parameters and tumor-acquired genetic variants, allowing for risk stratification and a more personalized approach to therapy. This article discusses the principles that can enable the rational and effective development of therapeutic approaches for high-risk multiple myeloma.

Efficacy and Toxicity Profile of Carfilzomib-Based Regimens for Treatment of Newly Diagnosed Multiple Myeloma: A Systematic Review

Carfilzomib (CFZ) is a proteasome inhibitor currently approved for the treatment of relapsed and refractory multiple myeloma (RRMM). Multiple trials are ongoing to evaluate its efficacy and safety in newly diagnosed multiple myeloma (NDMM). The use of CFZ-based two- or three-drug combination regimens as induction for the management of NDMM is an emerging approach. CFZ-based regimens include combinations of immunomodulators, alkylating agents, and monoclonal antibodies along with dexamethasone. In this review, we assess the efficacy and toxicity of CFZ-based regimens in NDMM. We reviewed a total of 27 studies (n=4538 patients) with overall response rates (ORR) ranging between 80% and 100%. Studies evaluating the combination of CFZ with daratumumab reported an ORR of approximately 100%. Achievement of minimal residual disease (MRD) negativity, measured by multi-parameter flow cytometry (MPFC), ranged between 60% and 95% in 4 (n=251) out of 6 studies that measured MRD-negativity. The interim results of the ENDURANCE trial failed to show superior efficacy and progression-free survival (PFS) of carfilzomib-lenalidomide when compared to bortezomib–lenalidomide combination, albeit with a lower incidence of neuropathy. Hematological toxicity was the most common adverse event observed with these regimens, and the most common non-hematological adverse events were related to cardiovascular and electrolyte disturbances. We need to further evaluate the role of CFZ in NDMM by conducting more Phase III trials with different combinations.

Carfilzomib, Lenalidomide, and Dexamethasone Followed by Lenalidomide Maintenance for Prevention of Symptomatic Multiple Myeloma in Patients With High-risk Smoldering Myeloma: A Phase 2 Nonrandomized Controlled Trial

Importance

High-risk smoldering myeloma has a 5-year risk of progression to symptomatic multiple myeloma of approximately 75%. Treatment with lenalidomide decreases the risk of progression; however, novel triplet regimens are superior, and earlier disease may be more treatment sensitive.

Objective

To evaluate the use of carfilzomib, lenalidomide, and dexamethasone (KRd) with lenalidomide maintenance therapy as early intervention in high-risk smoldering myeloma and to determine the rates of minimal residual disease (MRD)-negative complete response (CR).

Design, Setting, and Participants

In this single-arm, single-center, phase 2 nonrandomized controlled trial, responses were evaluated at every cycle during KRd treatment and every 3 cycles subsequently. Bone marrow biopsies and imaging were performed by cycle 8 and then annually. The study enrolled patients from May 29, 2012, to July 23, 2020, at the National Institutes of Health Clinical Center, a highly specialized tertiary cancer center. Patient key eligibility criteria included a diagnosis of high-risk smoldering myeloma based on the Mayo Clinic, Spanish, and/or Rajkumar, Mateos, and Landgren criteria.

Interventions

Patients received eight 4-week cycles of intravenous carfilzomib 36 mg/m2 (first 2 doses, 20 mg/m2), dexamethasone (20 mg, cycles 1-4; 10 mg, cycles 5-8 twice weekly), and lenalidomide 25 mg (days 1-21) followed by twenty-four 28-day cycles of maintenance lenalidomide 10 mg (days 1-21). Stem cell harvest and storage were optional.

Main Outcomes and Measures

The primary outcome was the MRD-negative CR rate. Key secondary outcomes included duration of MRD-negative CR and progression to multiple myeloma.

Results

A total of 54 patients (median age, 59 years [range, 40-79 years]; 30 men [55.6%]; and 2 Asian [3.7%], 15 Black [27.8%], 1 Hispanic [1.9%], and 36 White [66.7%] patients) were enrolled, with a median potential follow-up time of 31.9 months (range, 6.7-102.9 months). The MRD-negative CR rate was 70.4% (95% CI, 56.4%-82.0%), with a median sustained duration of 5.5 years (95% CI, 3.7 years to not estimable). The 8-year probability of being free from progression to multiple myeloma was 91.2% (95% CI, 67.4%-97.9%), and no deaths occurred. Nonhematologic grade 3 adverse events occurred in 21 patients (38.9%) and included thromboembolism, rash, and lung infection, with no grade 4 events.

Conclusions and Relevance

Results of this phase 2 nonrandomized controlled trial suggest that treatment of high-risk smoldering myeloma with novel triplet regimens, such as KRd and lenalidomide maintenance therapy, may alter the natural history of smoldering myeloma by significantly delaying development of end-organ disease. Randomized clinical trials are needed to confirm this favorable benefit-to-risk profile.

Trial Registration

ClinicalTrials.gov Identifier: NCT01572480.

Knowing the unknowns in high risk multiple myeloma

High risk multiple myeloma (HRMM) continues to portend worse outcomes despite the many advances in anti-myeloma therapeutics. The optimal approach to treatment is not clearly defined on account of the variable definitions of HRMM and the paucity of studies dedicated to the treatment of HRMM. In this review, we use a case-based approach to review the definitions of HRMM, and evaluate the evidence for induction, stem cell transplantation, and post-transplant therapy approaches for HRMM.

Integrative analysis of the genomic and transcriptomic landscape of double-refractory multiple myeloma

In multiple myeloma, novel treatments with proteasome inhibitors (PIs) and immunomodulatory agents (IMiDs) have prolonged survival but the disease remains incurable. At relapse, next-generation sequencing has shown occasional mutations of drug targets but has failed to identify unifying features that underlie chemotherapy resistance. We studied 42 patients refractory to both PIs and IMiDs. Whole-exome sequencing was performed in 40 patients, and RNA sequencing (RNA-seq) was performed in 27. We found more mutations than were reported at diagnosis and more subclonal mutations, which implies ongoing evolution of the genome of myeloma cells during treatment. The mutational landscape was different from that described in published studies on samples taken at diagnosis. The TP53 pathway was the most frequently inactivated (in 45% of patients). Conversely, point mutations of genes associated with resistance to IMiDs were rare and were always subclonal. Refractory patients were uniquely characterized by having a mutational signature linked to exposure to alkylating agents, whose role in chemotherapy resistance and disease progression remains to be elucidated. RNA-seq analysis showed that treatment or mutations had no influence on clustering, which was instead influenced by karyotypic events. We describe a cluster with both amp(1q) and del(13) characterized by CCND2 upregulation and also overexpression of MCL1, which represents a novel target for experimental treatments. Overall, high-risk features were found in 65% of patients. However, only amp(1q) predicted survival. Gene mutations of IMiD and PI targets are not a preferred mode of drug resistance in myeloma. Chemotherapy resistance of the bulk tumor population is likely attained through differential, yet converging evolution of subclones that are overall variable from patient to patient and within the same patient.

Minimal residual disease in multiple myeloma: defining the role of next generation sequencing and flow cytometry in routine diagnostic use

For patients diagnosed with multiple myeloma (MM) there have been significant treatment advances over the past decade, reflected in an increasing proportion of patients achieving durable remissions. Clinical trials repeatedly demonstrate that achieving a deep response to therapy, with a bone marrow assessment proving negative for minimal residual disease (MRD), confers a significant survival advantage. To accurately assess for minute quantities of residual cancer requires highly sensitive methods; either multiparameter flow cytometry or next generation sequencing are currently recommended for MM response assessment. Under optimal conditions, these methods can detect one aberrant cell amongst 1,000,000 normal cells (a sensitivity of 10^-6). Here, we will review the practical use of MRD assays in MM, including challenges in implementation for the routine diagnostic laboratory, standardisation across laboratories and clinical trials, the clinical integration of MRD status assessment into MM management and future directions for ongoing research.

Defining the undetectable: The current landscape of minimal residual disease assessment in multiple myeloma and goals for future clarity

Multiple Myeloma, the second most prevalent hematologic malignancy, yet lacks an established curative therapy. However, overall response rate to modern four-drug regimens approaches 100%. Major efforts have thus focused on the measurement of minute quantities of residual disease (minimal residual disease or MRD) for prognostic metrics and therapeutic response evaluation. Currently, MRD is assessed by flow cytometry or by next generation sequencing to track tumor-specific immunoglobulin V(D)J rearrangements. These bone marrow-based methods can reach sensitivity thresholds of the identification of one neoplastic cell in 1,000,000 (10-6). New technologies are being developed to be used alone or in conjunction with established methods, including peripheral blood-based assays, mass spectrometry, and targeted imaging. Data is also building for MRD as a surrogate endpoint for overall survival. Here, we will address the currently utilized MRD assays, challenges in validation across labs and clinical trials, techniques in development, and future directions for successful clinical application of MRD in multiple myeloma.

A phase 1b study of once-weekly carfilzomib combined with lenalidomide and dexamethasone in patients with newly diagnosed multiple myeloma

Twice‐weekly carfilzomib with lenalidomide‐dexamethasone (Rd) is an effective regimen for newly diagnosed multiple myeloma (NDMM). Here we evaluated once‐weekly carfilzomib with Rd (once‐weekly KRd) in NDMM patients. The NDMM patients were enrolled regardless of transplant eligibility. Patients received carfilzomib on days 1, 8, and 15; lenalidomide 25 mg on days 1‐21; and dexamethasone 40 mg on carfilzomib days (also day 22 for cycles 1‐8) for ≤18, 28‐day cycles. Enrollment initiated in a carfilzomib 20/70 mg/m² (20 mg/m² on cycle one, day 1; 70 mg/m² thereafter) NDMM dose‐expansion arm, which was suspended because of serious adverse events. After evaluation of dose‐limiting toxicities in a two‐step‐up dose‐evaluation cohort, an NDMM dose‐expansion arm (carfilzomib 20/56 mg/m²) was opened. Fifty‐one NDMM patients were enrolled in dose‐finding and dose‐expansion cohorts. Results are presented for the carfilzomib 56 mg/m² NDMM dose‐expansion arm (n = 33). The grade ≥ 3 treatment‐emergent AE (TEAE) rate was 63.6%. Twenty‐five patients underwent stem cell collection; 18 proceeded to auto stem cell transplant, and five resumed KRd on study after autoSCT. The overall response rate (ORR) based on best overall response by cycle four was 97.0% (≥very good partial response [VGPR], 69.7%) in the NDMM 20/56 mg/m² cohort. In patients who did not receive autoSCT (n = 15), the median number of cycles was 16.0; ORR was 93.3% (≥VGPR, 80.0%). At a median follow‐up of 8.1 months, median progression‐free survival was not reached. Once‐weekly KRd (carfilzomib 56 mg/m²) had a favorable safety profile and promising activity in NDMM, supporting the use of this regimen in this setting.

The role of high-dose melphalan with autologous stem-cell transplant in multiple myeloma: is it time for a paradigm shift?

Recent advances in multiple myeloma include numerous approvals of novel therapies with unprecedented efficacy, a rapid and sustained tempo of new drug development, and further refinements to prognostication to include minimal residual disease (MRD) testing and improved risk stratification. The upfront use of immunomodulatory drug and proteasome inhibitor combinations followed by maintenance has resulted in transformative clinical benefit. Four-drug regimens incorporating monoclonal antibodies are reporting unprecedented rates of complete response and MRD negativity in the absence of intensification. In the context of these advances, the added value of high-dose melphalan with autologous stem-cell transplant (HDM-ASCT) is a key question. From a safety standpoint, HDM-ASCT is associated with both acute toxicities that reduce quality of life and long-term toxicities that may limit life expectancy for some patients. The present review discusses the recent advances in induction therapy, the impact of these advances on HDM-ASCT, the evolving role of MRD testing and the short- and long-term risks of HDM-ASCT. Recognising that prospective data remains limited, we suggest that HDM-ASCT not be considered mandatory for eligible newly diagnosed patients who are treated with highly efficacious regimens and achieve deep responses, but rather be held in reserve without early exposure to the clinical and genomic toxicity inherent to this approach.

Minimal Residual Disease in Multiple Myeloma: State of the Art and Applications in Clinical Practice

Novel drugs have revolutionized multiple myeloma therapy in the last 20 years, with median survival that has doubled to up to 8–10 years. The introduction of therapeutic strategies, such as consolidation and maintenance after autologous stem cell transplants, has also ameliorated clinical results. The goal of modern therapies is becoming not only complete remission, but also the deepest possible remission. In this context, the evaluation of minimal residual disease by techniques such as next-generation sequencing (NGS) and next-generation flow (NGF) is becoming part of all new clinical trials that test drug efficacy. This review focuses on minimal residual disease approaches in clinical trials, with particular attention to real-world practices.

Carfilzomib or bortezomib in combination with lenalidomide and dexamethasone for patients with newly diagnosed multiple myeloma without intention for immediate autologous stem-cell transplantation (ENDURANCE): a multicentre, open-label, phase 3, randomised, controlled trial

BACKGROUND

Bortezomib, lenalidomide, and dexamethasone (VRd) is a standard therapy for newly diagnosed multiple myeloma. Carfilzomib, a next-generation proteasome inhibitor, in combination with lenalidomide and dexamethasone (KRd), has shown promising efficacy in phase 2 trials and might improve outcomes compared with VRd. We aimed to assess whether the KRd regimen is superior to the VRd regimen in the treatment of newly diagnosed multiple myeloma in patients who were not being considered for immediate autologous stem-cell transplantation (ASCT).

METHODS

In this multicentre, open-label, phase 3, randomised controlled trial (the ENDURANCE trial; E1A11), we recruited patients aged 18 years or older with newly diagnosed multiple myeloma who were ineligible for, or did not intend to have, immediate ASCT. Participants were recruited from 272 community oncology practices or academic medical centres in the USA. Key inclusion criteria were the absence of high-risk multiple myeloma and an Eastern Cooperative Oncology Group performance status of 0-2. Enrolled patients were randomly assigned (1:1) centrally by use of permuted blocks to receive induction therapy with either the VRd regimen or the KRd regimen for 36 weeks. Patients who completed induction therapy were then randomly assigned (1:1) a second time to either indefinite maintenance or 2 years of maintenance with lenalidomide. Randomisation was stratified by intent for ASCT at disease progression for the first randomisation and by the induction therapy received for the second randomisation. Allocation was not masked to investigators or patients. For 12 cycles of 3 weeks, patients in the VRd group received 1·3 mg/m² of bortezomib subcutaneously or intravenously on days 1, 4, 8, and 11 of cycles 1-8, and day 1 and day 8 of cycles nine to twelve, 25 mg of oral lenalidomide on days 1-14, and 20 mg of oral dexamethasone on days 1, 2, 4, 5, 8, 9, 11, and 12. For nine cycles of 4 weeks, patients in the KRd group received 36 mg/m² of intravenous carfilzomib on days 1, 2, 8, 9, 15, and 16, 25 mg of oral lenalidomide on days 1-21, and 40 mg of oral dexamethasone on days 1, 8, 15, and 22. The coprimary endpoints were progression-free survival in the induction phase, and overall survival in the maintenance phase. The primary analysis was done in the intention-to-treat population and safety was assessed in patients who received at least one dose of their assigned treatment. The trial is registered with ClinicalTrials.gov, NCT01863550. Study recruitment is complete, and follow-up of the maintenance phase is ongoing.

FINDINGS

Between Dec 6, 2013, and Feb 6, 2019, 1087 patients were enrolled and randomly assigned to either the VRd regimen (n=542) or the KRd regimen (n=545). At a median follow-up of 9 months (IQR 5-23), at a second planned interim analysis, the median progression-free survival was 34·6 months (95% CI 28·8-37·8) in the KRd group and 34·4 months (30·1-not estimable) in the VRd group (hazard ratio [HR] 1·04, 95% CI 0·83-1·31; p=0·74). Median overall survival has not been reached in either group. The most common grade 3-4 treatment-related non-haematological adverse events included fatigue (34 [6%] of 527 patients in the VRd group vs 29 [6%] of 526 in the KRd group), hyperglycaemia (23 [4%] vs 34 [6%]), diarrhoea (23 [5%] vs 16 [3%]), peripheral neuropathy (44 [8%] vs four [<1%]), dyspnoea (nine [2%] vs 38 [7%]), and thromboembolic events (11 [2%] vs 26 [5%]). Treatment-related deaths occurred in two patients (<1%) in the VRd group (one cardiotoxicity and one secondary cancer) and 11 (2%) in the KRd group (four cardiotoxicity, two acute kidney failure, one liver toxicity, two respiratory failure, one thromboembolic event, and one sudden death).

INTERPRETATION

The KRd regimen did not improve progression-free survival compared with the VRd regimen in patients with newly diagnosed multiple myeloma, and had more toxicity. The VRd triplet regimen remains the standard of care for induction therapy for patients with standard-risk and intermediate-risk newly diagnosed multiple myeloma, and is a suitable treatment backbone for the development of combinations of four drugs.

FUNDING

US National Institutes of Health, National Cancer Institute, and Amgen.

Autologous stem-cell collection following VTD or VRD induction therapy in multiple myeloma: a single-center experience

Triplet-drug regimen bortezomib-thalidomide-dexamethasone (VTD) and bortezomib-lenalidomide-dexamethasone (VRD) are considered as standard of care induction prior autologous stem-cell transplantation (ASCT) in myeloma. In addition to improve response rate, induction therapy should preserve an adequate stem-cell collection. In the present retrospective study, we analyzed stem-cell collection in 325 newly diagnosed myeloma patients who received either VTD or VRD induction before ASCT. Stem-cell mobilization consisted of intravenous cyclophosphamide plus G-CSF. Plerixafor was administered preemptively to rescue mobilization. In comparison with VTD, VRD induction was associated with a more frequent use of plerixafor (19.3% versus 5.4%, p = 0.004) and with an increased number of apheresis to reach adequate collection (>2 apheresis required in 42.3% versus 30.2%, p = 0.05). Moreover, more patients experienced collection failure in the VRD group (6% versus 1.8%, p = 0.004). The median number of CD34-positive cells (×10⁶/kg) was lower in the VRD group: 8.5 versus 9.3 (p = 0.05) in the VTD group. The vast majority of patients underwent ASCT (93% versus 98%, in VRD and VTD group, respectively). These data highlight the need of optimal stem-cell collection strategy, especially in the context of tandem transplantation and incorporation of anti-CD38 monoclonal antibody into induction.

Carfilzomib, dexamethasone, and daratumumab versus carfilzomib and dexamethasone for patients with relapsed or refractory multiple myeloma (CANDOR): results from a randomised, multicentre, open-label, phase 3 study

BACKGROUND

Lenalidomide and bortezomib frontline exposure has raised a growing need for novel treatments for patients with relapsed or refractory multiple myeloma. Carfilzomib in combination with daratumumab has shown substantial efficacy with tolerable safety in relapsed or refractory multiple myeloma in a phase 1 study. In this study, we aimed to compare the efficacy and safety of carfilzomib, dexamethasone, and daratumumab versus carfilzomib and dexamethasone in patients with relapsed or refractory multiple myeloma.

METHODS

In this randomised, multicentre, open-label, phase 3 study, 466 patients recruited from 102 sites across North America, Europe, Australia, and Asia with relapsed or refractory multiple myeloma were randomly assigned 2:1 to carfilzomib, dexamethasone, and daratumumab (KdD) or carfilzomib and dexamethasone (Kd). All patients received twice per week carfilzomib at 56 mg/m² (20 mg/m²; days 1 and 2 during cycle 1). Daratumumab (8 mg/kg) was administered intravenously on days 1 and 2 of cycle 1 and at 16 mg/kg weekly for the remaining doses of the first two cycles, then every 2 weeks for four cycles (cycles 3-6), and every 4 weeks thereafter. Patients received 40 mg dexamethasone weekly (20 mg for patients ≥75 years old starting on the second week). The primary endpoint was progression-free survival assessed by intention to treat. Adverse events were assessed in the safety population. This trial (NCT03158688) is registered with ClinicalTrials.gov, and is active but not recruiting.

FINDINGS

Between June 13, 2017, and June 25, 2018, 466 patients of 569 assessed for eligibility were enrolled. After median follow-up of approximately 17 months, median progression-free survival was not reached in the KdD group versus 15·8 months in the Kd group (hazard ratio 0·63; 95% CI 0·46-0·85; p=0·0027). Median treatment duration was longer in the KdD versus the Kd group (70·1 vs 40·3 weeks). Grade 3 or higher adverse events were reported in 253 (82%) patients in the KdD group and 113 (74%) patients in the Kd group. The frequency of adverse events leading to treatment discontinuation was similar in both groups (KdD, 69 [22%]; Kd, 38 [25%]).

INTERPRETATION

KdD significantly prolonged progression-free survival versus Kd in patients with relapsed or refractory multiple myeloma and was associated with a favourable benefit-risk profile.

FUNDING

Amgen.

Second malignancies in multiple myeloma; emerging patterns and future directions

The changing landscape of treatment options for multiple myeloma has led to a higher proportion of patients achieving deep, long-lasting responses to therapy. With the associated improvement in overall survival, the development of subsequent second malignancies has become of increased significance. The risk of second malignancy after multiple myeloma is affected by a combination of patient-, disease- and therapy-related risk factors. This review discusses recent data refining our knowledge of these contributing factors, including current treatment modalities which increase risk (i.e. high-dose melphalan with autologous stem cell transplant and lenalidomide maintenance therapy). We highlight emerging data towards individualized risk- and response-adapted treatment strategies and discuss key areas requiring future research.

The changing role of high dose melphalan with stem cell rescue in the treatment of newly diagnosed multiple myeloma in the era of modern therapies-back to the future!

State of the art treatment for myeloma involves using 3-drug combinations incorporating immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs). Clinical trials for 4-drug combinations incorporating monoclonal antibodies added to IMiD and PI based backbones are underway. Recent retrospective analyses show that patients who attain MRD negativity have similar long term outcomes regardless of early or delayed high dose melphalan with autologous stem cell support (HDM-ASCT). Given HDM-ASCT toxicity, not "overtreating" would be beneficial. Short of data from future prospective clinical trials addressing the question of the role of HDM-ASCT in MRD negative patients, varying expert opinions inherently arise. In this paper, we present the historical context of HDM-ASCT and data supporting 3-drug combinations. We then propose that a viable option for patients who reach MRD negativity is to transition to maintenance therapy directly without early HDM-ASCT, and reserving stem cell harvest to cases where HDM-ASCT is a possibility at relapse.

Comprehensive detection of recurring genomic abnormalities: a targeted sequencing approach for multiple myeloma

Recent genomic research efforts in multiple myeloma have revealed clinically relevant molecular subgroups beyond conventional cytogenetic classifications. Implementing these advances in clinical trial design and in routine patient care requires a new generation of molecular diagnostic tools. Here, we present a custom capture next-generation sequencing (NGS) panel designed to identify rearrangements involving the IGH locus, arm level, and focal copy number aberrations, as well as frequently mutated genes in multiple myeloma in a single assay. We sequenced 154 patients with plasma cell disorders and performed a head-to-head comparison with the results from conventional clinical assays, i.e., fluorescent in situ hybridization (FISH) and single-nucleotide polymorphism (SNP) microarray. Our custom capture NGS panel had high sensitivity (>99%) and specificity (>99%) for detection of IGH translocations and relevant chromosomal gains and losses in multiple myeloma. In addition, the assay was able to capture novel genomic markers associated with poor outcome such as bi-allelic events involving TP53. In summary, we show that a multiple myeloma designed custom capture NGS panel can detect IGH translocations and CNAs with very high concordance in relation to FISH and SNP microarrays and importantly captures the most relevant and recurrent somatic mutations in multiple myeloma rendering this approach highly suitable for clinical application in the modern era.

Cereblon gene variants and clinical outcome in multiple myeloma patients treated with lenalidomide

Carfilzomib-lenalidomide-dexamethasone (KRd) therapy has yielded promising results in patients with newly diagnosed multiple myeloma (NDMM). Cereblon (CRBN) is the direct molecular target of lenalidomide and genetic polymorphisms in CRBN have been associated with lenalidomide efficacy. In this study, we assessed the correlation of five single nucleotide variants (SNVs) in the CRBN gene with clinical response and outcomes in patients with NDMM administered KRd therapy with lenalidomide maintenance, achieving favorable trial endpoints in a prospective Phase II study (NCT01402284). Of the observed SNVs, no associations with KRd therapy response were found in this patient cohort, although strong trends in hypoalbuminemia grade and hyperbilirubinemia grade emerged across the CRBN rs1672753 genotype (P = 0.0008) and the rs1714327 genotype (P = 0.0010), respectively. Our results do not provide conclusive support for the predictive utility of CRBN gene polymorphisms as potential biomarkers of clinical response to lenalidomide-based therapy in our patient population. However, these findings remain to be validated in prospective studies using larger patient populations.

Delaying the use of high-dose melphalan with stem cell rescue in multiple myeloma is ready for prime time

The significant advances made in the treatment of multiple myeloma (MM) have allowed for a paradigm shift away from the early use of high-dose melphalan with autologous stem cell transplant (HDM-ASCT). In 2015 alone, the US Food and Drug Administration (FDA) approved 4 novel drugs for MM. Novel drugs and regimens have shown unprecedented efficacy, which has increased the tempo of new drug development. Furthermore, the FDA recently approved a diagnostic test to detect minimal residual disease (MRD) that will allow community clinicians to conduct real-time testing of MRD. Most importantly, frontline regimens based on immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs) have shown a large clinical benefit. The next era has begun, as several 4-drug combinations that include monoclonal antibodies are being evaluated in clinical trials in the attempt to replace HDM-ASCT in the treatment of MM. We and others have therefore questioned the need for early HDM-ASCT, especially in light of the possible complications. HDM-ASCT is associated not only with acute toxicities-cytopenia, infection, and even death-but also an increased risk of developing secondary cancers. This article discusses the historic context of HDM-ASCT, the modern role of HDM-ASCT given the availability of highly sensitive MRD testing, and the likely future of quadruplet treatment. In summary, patients who attain deep responses using IMiD- and PI-based regimens may not require early HDM-ASCT. A delayed approach to this treatment is acceptable, and might be preferred by patients.

Carfilzomib with immunomodulatory drugs for the treatment of newly diagnosed multiple myeloma

Carfilzomib, a selective proteasome inhibitor (PI), is approved for the treatment of patients with relapsed or refractory multiple myeloma (MM). Combination regimens incorporating a PI and immunomodulatory drug (IMiD) have been associated with deep responses and extended survival in patients with newly diagnosed MM (NDMM). Carfilzomib-based combinations with immunomodulators are being extensively studied in the frontline setting. The objective of this review was to describe efficacy and safety data for carfilzomib-based, PI/immunomodulatory combinations in NDMM. Information sources were articles indexed in PubMed and abstracts from key hematology/oncology congresses published between January 2012 and December 2018. PubMed and congresses were searched for prospective clinical studies assessing the combination of carfilzomib with an IMiD for NDMM treatment. Retrospective and preclinical reports, case reports/series, reviews, and clinical studies not evaluating carfilzomib-immunomodulator combinations in NDMM were excluded based on review of titles and abstracts. A total of nine articles and 72 abstracts were deemed relevant and included in the review. A total of six distinct carfilzomib-based, PI/immunomodulator combination regimens have been evaluated in 12 clinical trials. Overall, treatment with these regimens has resulted in deep responses, including high rates of negativity for minimal residual disease. These deep responses have translated to long progression-free survival and overall survival rates. Efficacy results for these regimens have generally been consistent across subgroups defined by age, transplant eligibility, and cytogenetic risk. The safety profile of carfilzomib in NDMM is consistent with that observed in the relapsed-refractory MM setting. Clinical studies have found that carfilzomib-based combinations with immunomodulators are highly active with a favorable safety profile in NDMM. The carfilzomib, lenalidomide, and dexamethasone (KRd) drug backbone is a promising foundation for treatment strategies aimed at achieving long-term, deep responses (functional cures) in the frontline setting. Several ongoing studies are evaluating KRd, with or without anti-CD38 monoclonal antibodies.

Baseline identification of clonal V(D)J sequences for DNA-based minimal residual disease detection in multiple myeloma

Tracking of clonal immunoglobulin V(D)J rearrangement sequences by next generation sequencing is highly sensitive for minimal residual disease in multiple myeloma. However, previous studies have found variable rates of V(D)J sequence identification at baseline, which could limit tracking. Here, we aimed to define the factors influencing the identification of clonal V(D)J sequences. Bone marrow mononuclear cells from 177 myeloma patients underwent V(D)J sequencing by the LymphoTrack assays (Invivoscribe). As a molecular control for tumor cell content, we sequenced the samples using our in-house myeloma panel myTYPE. V(D)J sequence clonality was identified in 81% of samples overall, as compared with 95% in samples where tumor-derived DNA was detectable by myTYPE. Clonality was detected more frequently in patients with lambda-restricted disease, mainly because of increased detection of kappa gene rearrangements. Finally, we describe how the tumor cell content of bone marrow aspirates decrease gradually in sequential pulls because of hemodilution: From the initial pull used for aspirate smear, to the final pull that is commonly used for research. In conclusion, baseline clonality detection rates of 95% or higher are feasible in multiple myeloma. Optimal performance depends on the use of good quality aspirates and/or subsequent tumor cell enrichment.