EVIDENCE meta-analysis: evaluating minimal residual disease as an intermediate clinical end point for multiple myeloma.

ABSTRACT: Estimating progression-free survival (PFS) and overall survival superiority during clinical trials of multiple myeloma (MM) has become increasingly challenging as novel therapeutics have improved patient outcomes. Thus, it is imperative to identify earlier end point surrogates that are predictive of long-term clinical benefit. Minimal residual disease (MRD)-negativity is a common intermediate end point that has shown prognostic value for clinical benefit in MM. This meta-analysis was based on the US Food and Drug Administration guidance for considerations for a meta-analysis of MRD as a clinical end point and evaluates MRD-negativity as an early end point reasonably likely to predict long-term clinical benefit. Eligible studies were phase 2 or 3 randomized controlled clinical trials measuring MRD-negativity as an end point in patients with MM, with follow-up of ≥6 months following an a priori-defined time point of 12 ± 3 months after randomization. Eight newly diagnosed MM studies evaluating 4907 patients were included. Trial-level associations between MRD-negativity and PFS were R2WLSiv, 0.67 (95% confidence interval [CI], 0.43-0.91) and R2copula 0.84 (0.64 to >0.99) at the 12-month time point. The individual-level association between 12-month MRD-negativity and PFS resulted in a global odds ratio (OR) of 4.02 (95% CI, 2.57-5.46). For relapse/refractory MM, there were 4 studies included, and the individual-level association between 12-month MRD-negativity and PFS resulted in a global OR of 7.67 (4.24-11.10). A clinical trial demonstrating a treatment effect on MRD is reasonably likely to eventually demonstrate a treatment effect on PFS, suggesting that MRD may be an early clinical end point reasonably likely to predict clinical benefit in MM, that may be used to support accelerated approval and thereby, expedite the availability of new drugs to patients with MM.

Epidemiology and clinical outcomes of light-chain amyloidosis in Sweden: A nationwide population-based study.

OBJECTIVES: This study evaluated data from six Swedish national registries to fill current evidence gaps on the epidemiology, clinical burden, and overall survival (OS) associated with light-chain (AL) amyloidosis. METHODS: Patients newly diagnosed with AL amyloidosis were identified using six linked Swedish nationwide population-based registers. For each case, individuals from the general population were selected and matched with a maximum ratio of 1:5 based on age, sex, calendar year, and county. RESULTS: 846 patients newly diagnosed with AL amyloidosis and 4227 demographically matched individuals were identified. From 2011 to 2019, annual AL amyloidosis incidence increased from 10.5 to 15.1 cases per million. At baseline, patients with AL amyloidosis had a significantly higher disease burden including higher rates of cardiac and renal failure relative to the comparison group. Among patients with AL amyloidosis, 21.5% had incident heart failure and 17.1% had incident renal failure after initial diagnosis. Median OS for patients with AL amyloidosis was 56 months versus not reached in the matched general population comparison group. CONCLUSION: The incidence of newly diagnosed AL amyloidosis in Sweden increased over time with AL amyloidosis being associated with a higher risk of cardiac/renal failure and all-cause mortality compared with the general population.

Longitudinal minimal residual disease assessment in multiple myeloma patients in complete remission - results from the NMSG flow-MRD substudy within the EMN02/HO95 MM trial.

BACKGROUND: Multiple myeloma remains an incurable disease with multiple relapses due to residual myeloma cells in the bone marrow of patients after therapy. Presence of small number of cancer cells in the body after cancer treatment, called minimal residual disease, has been shown to be prognostic for progression-free and overall survival. However, for multiple myeloma, it is unclear whether patients attaining minimal residual disease negativity may be candidates for treatment discontinuation. We investigated, if longitudinal flow cytometry-based monitoring of minimal residual disease (flow-MRD) may predict disease progression earlier and with higher sensitivity compared to biochemical assessments. METHODS: Patients from the Nordic countries with newly diagnosed multiple myeloma enrolled in the European-Myeloma-Network-02/Hovon-95 (EMN02/HO95) trial and undergoing bone marrow aspiration confirmation of complete response, were eligible for this Nordic Myeloma Study Group (NMSG) substudy. Longitdudinal flow-MRD assessment of bone marrow samples was performed to identify and enumerate residual malignant plasma cells until observed clinical progression. RESULTS: Minimal residual disease dynamics were compared to biochemically assessed changes in serum free light chain and M-component. Among 20 patients, reaching complete response or stringent complete response during the observation period, and with ≥3 sequential flow-MRD assessments analysed over time, increasing levels of minimal residual disease in the bone marrow were observed in six cases, preceding biochemically assessed disease and clinical progression by 5.5 months and 12.6 months (mean values), respectively. Mean malignant plasma cells doubling time for the six patients was 1.8 months (95% CI, 1.4-2.3 months). Minimal malignant plasma cells detection limit was 4 × 10-5. CONCLUSIONS: Flow-MRD is a sensitive method for longitudinal monitoring of minimal residual disease dynamics in multiple myeloma patients in complete response. Increasing minimal residual disease levels precedes biochemically assessed changes and is an early indicator of subsequent clinical progression. TRIAL REGISTRATION: NCT01208766.

Treatment of relapsed and refractory multiple myeloma: recommendations from the International Myeloma Working Group.

This Policy Review presents the International Myeloma Working Group's clinical practice recommendations for the treatment of relapsed and refractory multiple myeloma. Based on the results of phase 2 and phase 3 trials, these recommendations are proposed for the treatment of patients with relapsed and refractory disease who have received one previous line of therapy, and for patients with relapsed and refractory multiple myeloma who have received two or more previous lines of therapy. These recommendations integrate the issue of drug access in both low-income and middle-income countries and in high-income countries to help guide real-world practice and thus improve patient outcomes.

Melflufen plus dexamethasone in relapsed/refractory multiple myeloma: long-term survival follow-up from the Phase II study O-12-M1.

An updated survival analysis was conducted for the Phase II study O-12-M1 of melphalan flufenamide (melflufen) plus dexamethasone in patients with relapsed/refractory multiple myeloma (RRMM) with two or more prior lines of therapy (including bortezomib and lenalidomide). Partial response or better was seen in 31%. After a 46-month median overall survival (OS) follow-up, melflufen plus dexamethasone had a median OS of 20·7 months (75th percentile OS, 47·5 months). The median time-to-next treatment for melflufen plus dexamethasone was 7·9 months. In summary, melflufen plus dexamethasone resulted in sustained long-term clinical benefit in patients with RRMM.

Autoimmune disease is associated with a lower risk of progression in monoclonal gammopathy of undetermined significance.

OBJECTIVES AND METHODS: We conducted a population-based study including 19 303 individuals diagnosed with MGUS in Sweden from 1985 to 2013, with the aim to determine whether a prior history of autoimmune disease, a well-described risk factor for MGUS is a risk factor for progression of MGUS to multiple myeloma (MM) or lymphoproliferative diseases (LPs). Using the nationwide Swedish Patient registry, we identified MGUS cases with versus without an autoimmune disease present at the time of MGUS diagnosis and estimated their risk of progression. RESULTS: A total of 5612 (29.1%) MGUS cases had preceding autoimmune diseases. Using Cox proportional hazards models, we found the risk of progression from MGUS to MM (HR = 0.83, 95% CI 0.73-0.94) and LPs (HR = 0.84, 95% CI 0.75-0.94) to be significantly lower in MGUS cases with prior autoimmune disease (compared to MGUS cases without). CONCLUSIONS: In this large population-based study, a history of autoimmune disease was associated with a reduced risk of progression from MGUS to MM/other LPs. Potential underlying reason is that MGUS caused by chronic antigen stimulation is biologically less likely to undergo the genetic events that trigger progression. Our results may have implications in clinical counseling for patients with MGUS and underlying autoimmune disease.

Health-related quality of life in transplant ineligible newly diagnosed multiple myeloma patients treated with either thalidomide or lenalidomide-based regimen until progression: a prospective, open-label, multicenter, randomized, phase 3 study.

Data on the impact of long term treatment with immunomodulatory drugs (IMiD) on health-related quality of life (HRQoL) is limited. The HOVON-87/NMSG18 study was a randomized, phase 3 study in newly diagnosed transplant ineligible patients with multiple myeloma, comparing melphalan-prednisolone in combination with thalidomide or lenalidomide, followed by maintenance therapy until progression (MPT-T or MPR-R). The EORTC QLQ-C30 and MY20 questionnaires were completed at baseline, after three and nine induction cycles and six and 12 months of maintenance therapy. Linear mixed models and minimal important differences were used for evaluation. 596 patients participated in HRQoL reporting. Patients reported clinically relevant improvement in global quality of life (QoL), future perspective and role and emotional functioning, and less fatigue and pain in both arms. The latter being of large effect size. In general, improvement occurred after 6-12 months of maintenance only and was independent of the World Health Organisation performance at baseline. Patients treated with MPR-R reported clinically relevant worsening of diarrhea, and patients treated with MPT-T reported a higher incidence of neuropathy. Patients who remained on lenalidomide maintenance therapy for at least three months reported clinically meaningful improvement in global QoL and role functioning at six months, remaining stable thereafter. There were no clinically meaningful deteriorations, but patients on thalidomide reported clinically relevant worsening in neuropathy. In general, HRQoL improves both during induction and maintenance therapy with immunomodulatory drugs. The side effect profile of treatment did not negatively affect global QoL, but it was, however, clinically relevant for the patients. (Clinicaltrials.gov identifier: NTR1630).

Outcome and characteristics of non-measurable myeloma: A cohort study with population-based data from the Swedish Myeloma Registry.

OBJECTIVE: We describe survival in patients with oligo- and non-secretory multiple myeloma (MM). We refer to the whole group as non-measurable MM and compare it with secretory MM. METHODS: Oligo-secretory MM was defined as M protein in serum <10 g/L and M protein in urine <200 measured as mg/day, mg/liter or mg/mmol creatinine. If patients had no M protein, they were defined as non-secretory. The groups were also subdivided by Free Light Chains (SFLC) level and ratio. RESULTS: Out of 4325 patients with symptomatic MM in the Swedish Myeloma Registry during 2008-2016 eligible for the study, 389 patients (9%) had non-measurable MM. Out of these, 253 patients (6%) had oligo-secretory and 136 (3%) had non-secretory MM. Median survival for secretory MM was 42.7 months, non-measurable MM 40.2 months, oligo-secretory MM 38.6 months, and non-secretory MM 44.6 months. Difference in overall observed survival was non-significant for all groups when compared with secretory MM. Within non-secretory MM, stem cell transplantation (SCT), 95% being auto-SCT, was significant for superior survival in multivariate analysis (HR 0.048. P = .0015). CONCLUSION: In this population-based study, we found no difference in survival between oligo- or non-secretory MM when compared with secretory MM. SCT appears to be important also for patients with non-secretory disease.

Melphalan, prednisone, and lenalidomide versus melphalan, prednisone, and thalidomide in untreated multiple myeloma.

The combination of melphalan, prednisone, and thalidomide (MPT) is considered standard therapy for newly diagnosed patients with multiple myeloma who are ineligible for stem cell transplantation. Long-term treatment with thalidomide is hampered by neurotoxicity. Melphalan, prednisone, and lenalidomide, followed by lenalidomide maintenance therapy, showed promising results without severe neuropathy emerging. We randomly assigned 668 patients between nine 4-week cycles of MPT followed by thalidomide maintenance until disease progression or unacceptable toxicity (MPT-T) and the same MP regimen with thalidomide being replaced by lenalidomide (MPR-R). This multicenter, open-label, randomized phase 3 trial was undertaken by Dutch-Belgium Cooperative Trial Group for Hematology Oncology and the Nordic Myeloma Study Group (the HOVON87/NMSG18 trial). The primary end point was progression-free survival (PFS). A total of 318 patients were randomly assigned to receive MPT-T, and 319 received MPR-R. After a median follow-up of 36 months, PFS with MPT-T was 20 months (95% confidence interval [CI], 18-23 months) vs 23 months (95% CI, 19-27 months) with MPR-R (hazard ratio, 0.87; 95% CI, 0.72-1.04; P = .12). Response rates were similar, with at least a very good partial response of 47% and 45%, respectively. Hematologic toxicity was more pronounced with MPR-R, especially grades 3 and 4 neutropenia: 64% vs 27%. Neuropathy of at least grade 3 was significantly higher in the MPT-T arm: 16% vs 2% in MPR-R, resulting in a significant shorter duration of maintenance therapy (5 vs 17 months in MPR-R), irrespective of age. MPR-R has no advantage over MPT-T concerning efficacy. The toxicity profile differed with clinically significant neuropathy during thalidomide maintenance vs myelosuppression with MPR.

Outcome and survival of myeloma patients diagnosed 2008-2015. Real-world data on 4904 patients from the Swedish Myeloma Registry.

Epidemiology and outcome of myeloma are mainly reported from large university centers and collaborative groups, and do not represent 'real-world' patients. The Swedish Myeloma Registry is a prospective population-based registry documenting characteristics, treatment and outcome in newly diagnosed myeloma, including asymptomatic and localized forms, with the purpose of improving disease management and outcome. This report presents information on patients diagnosed between 2008 and 2015, including data on first-line treatment in patients diagnosed up to 2014, with a follow up until December 2016. We present age-adjusted incidence, patients' characteristics at baseline, treatment, response, and survival. Baseline data were available with a 97% coverage in 4904 patients (median age 71 years, males 70 years, females 73 years; 72% were 65 years or older), and at 1-year follow up in 3558 patients with symptomatic disease (92% of patients initially reported). The age-adjusted incidence was 6.8 myeloma cases per 100,000 inhabitants per year. Among initially symptomatic patients (n=3988), 77% had osteolytic lesions or compression fractures, 49% had anemia, 18% impaired kidney function, and 13% hypercalcemia. High-dose therapy with autologous stem cell transplantation was given to 77% of patients aged up to 66 years, and to 22% of patients aged 66-70 years. In the study period, 68% received bortezomib, thalidomide, and/or lenalidomide as part of the first-line treatment, rising from 31% in 2008 to 81% in 2014. In active myeloma, the median relative survival of patients aged 65 years or under was 7.7 years, and 3.4 years in patients aged 66 years and over. Patients diagnosed with myeloma in more recent years were associated with significantly higher rates of complete or very good partial remission (P<0.05), and with a significantly higher survival, with a Hazard Ratio (HR) of 0.84 (95%CI: 0.77-0.92; P<0.05). There was a small, but significant survival benefit in patients treated at university hospitals (HR 0.93; 95%CI: 0.87-0.99; P<0.05). We report here on a near complete 'real-world' population of myeloma patients during an 8-year period; a period in which newer drugs were implemented into standard practice. The overall incidence and median age were both higher than in most previous studies, indicating a more complete coverage of older patients. Myeloma survival in Sweden is comparable to other large registry studies, and responses and survival improved during the study period.

New prognostic tools for myeloma.

In this issue of Blood, Palumbo et al show, in a study performed with the cooperation of the International Myeloma Working Group (IMWG), that detailed systematic geriatric assessment of elderly myeloma patients might be a useful tool for identifying fit and frail individuals. Like most malignancies, multiple myeloma mainly affects elderly patients. Even so, in daily clinical practice, we usually only consider chronological age (i.e., is the patient under or above 65 years of age?). However, it is quite obvious that there is a huge difference between a 70-year-old fit patient and a frail patient above the age of 80.

Incidence, characteristics, and outcome of solitary plasmacytoma and plasma cell leukemia. Population-based data from the Swedish Myeloma Register.

Solitary plasmacytoma (SP) and plasma cell leukemia (PCL) are uncommon (3-6%) types of plasma cell disease. The risk of progression to symptomatic multiple myeloma (MM) is probably important for the outcome of SP. PCL is rare and has a dismal outcome. In this study, we report on incidence and survival in PCL/SP, and progression to MM in SP, using the prospective observational Swedish Multiple Myeloma Register designed to document all newly diagnosed plasma cell diseases in Sweden since 2008. Both solitary bone plasmacytoma (SBP) (n=124) and extramedullary plasmacytoma (EMP) (n=67) have better overall survival (OS) than MM (n=3549). Progression to MM was higher in SBP than in EMP (35% and 7% at 2 years, respectively), but this did not translate into better survival in EMP. In spite of treatment developments, the OS of primary PCL is still dismal (median of 11 months, 0% at 5 years). Hence, there is a great need for diagnostic and treatment guidelines as well as prospective studies addressing the role for alternative treatment options, such as allogeneic stem cell transplantation and monoclonal antibodies in the treatment of PCL.

Bortezomib consolidation after autologous stem cell transplantation in multiple myeloma: a Nordic Myeloma Study Group randomized phase 3 trial.

The Nordic Myeloma Study Group conducted an open randomized trial to compare bortezomib as consolidation therapy given after high-dose therapy and autologous stem cell transplantation (ASCT) with no consolidation in bortezomib-naive patients with newly diagnosed multiple myeloma. Overall, 370 patients were centrally randomly assigned 3 months after ASCT to receive 20 doses of bortezomib given during 21 weeks or no consolidation. The hypothesis was that consolidation therapy would prolong progression-free survival (PFS). The PFS after randomization was 27 months for the bortezomib group compared with 20 months for the control group (P = .05). Fifty-one of 90 patients in the treatment group compared with 32 of 90 controls improved their response after randomization (P = .007). No difference in overall survival was seen. Fatigue was reported more commonly by the bortezomib-treated patients in self-reported quality-of-life (QOL) questionnaires, whereas no other major differences in QOL were recorded between the groups. Consolidation therapy seemed to be beneficial for patients not achieving at least a very good partial response (VGPR) but not for patients in the ≥ VGPR category at randomization. Consolidation with bortezomib after ASCT in bortezomib-naive patients improves PFS without interfering with QOL. This trial was registered at www.clinicaltrials.gov as #NCT00417911.

Multiple myeloma and infections: a population-based study on 9253 multiple myeloma patients.

Infections are a major cause of morbidity and mortality in patients with multiple myeloma. To estimate the risk of bacterial and viral infections in multiple myeloma patients, we used population-based data from Sweden to identify all multiple myeloma patients (n=9253) diagnosed from 1988 to 2004 with follow up to 2007 and 34,931 matched controls. Cox proportional hazard models were used to estimate the risk of infections. Overall, multiple myeloma patients had a 7-fold (hazard ratio =7.1; 95% confidence interval = 6.8-7.4) risk of developing any infection compared to matched controls. The increased risk of developing a bacterial infection was 7-fold (7.1; 6.8-7.4), and for viral infections 10-fold (10.0; 8.9-11.4). Multiple myeloma patients diagnosed in the more recent calendar periods had significantly higher risk of infections compared to controls (P<0.001). At one year of follow up, infection was the underlying cause in 22% of deaths in multiple myeloma patients. Mortality due to infections remained constant during the study period. Our findings confirm that infections represent a major threat to multiple myeloma patients. The effect on infectious complications due to novel drugs introduced in the treatment of multiple myeloma needs to be established and trials on prophylactic measures are needed.

Improved survival in myeloma patients: starting to close in on the gap between elderly patients and a matched normal population.

The outcome for multiple myeloma patients has improved since the introduction of bortezomib, thalidomide and lenalidomide. However, studies comparing new and conventional treatment include selected patient groups. We investigated consecutive patients (n = 1638) diagnosed in a defined period and compared survival with a gender- and age-matched cohort Swedish population (n = 9 340 682). Median overall survival for non-high-dose treated patients was 2·8 years. The use of bortezomib, thalidomide or lenalidomide in first line therapy predicted a significantly longer overall survival (median 4·9 years) compared to conventional treatment (2·3 years). Among non-high-dose treated patients receiving at least 2 lines with bortezomib, thalidomide or lenalidomide, 69% and 63% have survived at 3 and 5 years as compared to 48% and 22% with conventional drugs and 88% and 79% in the matched cohort populations, respectively. The median overall survival in high-dose treated patients was 6·9 years. Of these patients, 84% survived at 3 years and 70% at 5 years as compared to 98% and 95% in the matched cohort population. Overall survival in the best non-high-dose treated outcome group is closing the gap with the matched cohort. Upfront use of new drugs is clearly better than waiting until later lines of treatment.

The choice of serum-free light chain analysis method could potentially have clinical consequences for myeloma patients.

Multiple myeloma (MM) is a disease, that at times poses diagnostic and monitoring challenges. Over the last decades laboratory methods have been expanded with serum free light chain (FLC) analysis. Alerted by two index cases with clinical impact due to failure of the FLC analysis to indicate a disease progression, we aimed to identify any clinical consequences due to known differences between FLC analysis methods. We applied two FLC analysis methods (Freelite Binding Site [FBS] and N-Latex Siemens [NLS]) on all patients with MM and monoclonal gammopathy of uncertain significance diagnosed/followed up at Södra Älvsborg Hematology Unit, from April to December 2022. From a total of 123 patients with malignant plasma cell disorder, we identified five cases (4.1%) where solely the FBS method, as opposed to NLS, urine and serum electrophoresis, could support diagnosis or detect progression. The consequences of this discrepancy included not only change of diagnosis or delayed therapy but also change of treatment. Our findings indicate that a stronger awareness of the potential weaknesses of different FLC methods is needed, which calls for a closer collaboration between clinical chemists and hematologists.

Effectiveness and infectious complications of BCMA T-cell engagers in treating multiple myeloma: Real-world evidence from Sweden.

BACKGROUND: Multiple myeloma (MM), an incurable disease characterized by frequent relapses and a need for multiple treatments, often progresses to a relapse/refractory status resistant to all available drugs and drug classes. Bispecific antibodies, specifically BCMA T-cell engagers, have emerged as effective treatments for MM, demonstrating impressive efficacy. However, these treatments can adversely affect the immune system, increasing vulnerability to infections. METHODS/RESULTS: This study evaluated the efficacy and safety of BCMA T-cell engagers in 58 Swedish patients with poor MM prognosis. The patients exhibited a 69% overall response rate, with 69% survival and 60% progression-free survival at 15 months. CONCLUSIONS: Despite the risk of infectious complications, the prognosis of MM patients can be significantly improved with vigilant monitoring and proactive management of infections. This real-world data highlight the potential of BCMA T-cell engagers in treating MM, emphasizing the need for careful patient monitoring to mitigate infection risks.

Deciphering the genetics and mechanisms of predisposition to multiple myeloma.

Multiple myeloma (MM) is an incurable malignancy of plasma cells. Epidemiological studies indicate a substantial heritable component, but the underlying mechanisms remain unclear. Here, in a genome-wide association study totaling 10,906 cases and 366,221 controls, we identify 35 MM risk loci, 12 of which are novel. Through functional fine-mapping and Mendelian randomization, we uncover two causal mechanisms for inherited MM risk: longer telomeres; and elevated levels of B-cell maturation antigen (BCMA) and interleukin-5 receptor alpha (IL5RA) in plasma. The largest increase in BCMA and IL5RA levels is mediated by the risk variant rs34562254-A at TNFRSF13B. While individuals with loss-of-function variants in TNFRSF13B develop B-cell immunodeficiency, rs34562254-A exerts a gain-of-function effect, increasing MM risk through amplified B-cell responses. Our results represent an analysis of genetic MM predisposition, highlighting causal mechanisms contributing to MM development.

Personal and family history of immune-related conditions increase the risk of plasma cell disorders: a population-based study.

The associations between immune-related conditions and multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS) have previously been investigated with inconsistent results. In a large population-based study, we identified 19 112 patients with MM, 5403 patients with MGUS, 96 617 matched control subjects, and 262 931 first-degree relatives. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) for the association of MM and MGUS with immune-related conditions by use of logistic regression. A personal history of all infections combined was associated with a significantly increased risk of MM (OR = 1.2; 95% CI, 1.1-1.3), and a personal history of all conditions in the categories infections (OR = 1.6; 95% CI, 1.5-1.7), inflammatory conditions (OR = 1.4; 95% CI, 1.2-1.5), and autoimmune diseases (OR = 2.1; 95% CI, 1.9-2.4) was associated with a significantly increased risk of MGUS. Several specific immune-related conditions elevated the risk of MM and/or MGUS. A family history of autoimmune disease was associated with a significantly increased risk of MGUS (OR = 1.1; 95% CI, 1.00-1.2), but not MM. Our findings suggest that immune-related conditions and/or their treatment are of importance in the etiology of MGUS and possibly MM. The association of both personal and family history of autoimmune disease with MGUS indicates the potential for shared susceptibility for these conditions.