Neha Korde

Monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM): novel biological insights and development of early treatment strategies.

Monoclonal gammopathy of unknown significance (MGUS) and smoldering multiple myeloma (SMM) are asymptomatic plasma cell dyscrasias, with a propensity to progress to symptomatic MM. In recent years there have been improvements in risk stratification models (involving molecular markers) of both disorders, which have led to better understanding of the biology and probability of progression of MGUS and SMM. In the context of numerous molecular events and heterogeneous risk of progression, developing individualized risk profiles for patients with MGUS and SMM represents an ongoing challenge that has to be addressed by prospective clinical monitoring and extensive correlative science. In this review we discuss the current standard of care of patients with MGUS and SMM, the use of risk models, including flow cytometry and free-light chain analyses, for predicting risk of progression. Emerging evidence from molecular studies on MGUS and SMM, involving cytogenetics, gene-expression profiling, and microRNA as well as molecular imaging is described. Finally, future directions for improving individualized management of MGUS and SMM patients, as well as the potential for developing early treatment strategies designed to delay and prevent development of MM are discussed.

Risk of acute myeloid leukemia and myelodysplastic syndromes after multiple myeloma and its precursor disease (MGUS).

Using population-based data from Sweden, we identified all multiple myeloma (MM) patients (n = 8740) and 5652 monoclonal gammopathy of undetermined significance (MGUS) patients diagnosed between 1986 and 2005. We calculated standardized incidence rates (SIRs) for all subsequent hematologic and nonhematologic malignancies for MM patients diagnosed before/after 1995 (introduction of high-dose melphalan/autologous stem cell transplantation [HDM-ASCT]) and 2000 (introduction of immunomodulatory drugs [IMiDs]), respectively. MM patients had an 11.51-fold (95% confidence interval: 8.19-15.74) increased risk of acute myeloid leukemia (AML)/myelodysplastic syndromes (MDS); risk was very similar before/after 1995 and 2000, respectively. MGUS patients had an 8.01-fold (5.40-11.43) increased risk of AML/MDS. Risk was confined to IgG/IgA, while no IgM MGUS patients developed AML/MDS; patients with monoclonal-protein (M-protein) concentrations > 1.5 g/dL (SIR = 11.12; 3.61-25.96) had higher risk than those < 1.5 g/dL (SIR = 4.67; 1.71-10.16). An excess risk of nonmelanoma skin cancer was observed subsequent to both MM (SIR = 2.22; 1.74-2.80) and MGUS (SIR = 3.30; 2.76-3.90). Our novel observations of an excess risk for AML/MDS following IgG/IgA (but not IgM) MGUS, and the highest risk associated with M-protein concentrations > 1.5 g/dL, support a role for nontreatment-related factors in plasma cell dyscrasias. AML/MDS risk following MM was the same before/after the introduction of HDM-ASCT. Longer follow-up is needed to characterize second tumor risks in the IMiD era.

Treatment With Carfilzomib-Lenalidomide-Dexamethasone With Lenalidomide Extension in Patients With Smoldering or Newly Diagnosed Multiple Myeloma.

IMPORTANCE Carfilzomib-lenalidomide-dexamethasone therapy yields deep responses in patients with newly diagnosed multiple myeloma (NDMM). It is important to gain an understanding of this combinations tolerability and impact on minimal residual disease (MRD) negativity because this end point has been associated with improved survival. OBJECTIVE To assess the safety and efficacy of carfilzomib-lenalidomide-dexamethasone therapy in NDMM and high-risk smoldering multiple myeloma (SMM). DESIGN, SETTING, AND PARTICIPANTS Clinical and correlative pilot study at the National Institutes of Health Clinical Center. Patients with NDMM or high-risk SMM were enrolled between July 11, 2011, and October 9, 2013. Median follow-up was 17.3 (NDMM) and 15.9 months (SMM). INTERVENTIONS Eight 28-day cycles were composed of carfilzomib 20/36 mg/m2 on days 1, 2, 8, 9, 15, and 16; lenalidomide 25 mg on days 1 through 21; and dexamethasone 20/10 mg (cycles 1-4/5-8) on days 1, 2, 8, 9, 15, 16, 22, and 23. Patients who achieved at least stable disease subsequently received 24 cycles of lenalidomide extended dosing. MAIN OUTCOMES AND MEASURES Primary end points were neuropathy of grade 3 or greater (NDMM) and at least very good partial response rates (SMM). Minimal residual disease was also assessed. RESULTS Of 45 patients with NDMM, none had neuropathy of grade 3 or greater. Of 12 patients with high-risk SMM, the most common of any-grade adverse events were lymphopenia (12 [100%]) and gastrointestinal disorders (11 [92%]). All patients with SMM achieved at least a very good partial response during the study period. Among the 28 patients with NDMM and the 12 with SMM achieving at least a near-complete response, MRD negativity was found in 28 of 28 (100% [95% CI, 88%-100%]), 11 of 12 (92% [95% CI, 62%-100%]) (multiparametric flow cytometry), 14 of 21 (67% [95% CI, 43%-85%]), and 9 of 12 (75% [95% CI, 43%-94%]) (next-generation sequencing), respectively. In patients with NDMM, 12-month progression-free survival for MRD-negative vs MRD-positive status by flow cytometry and next-generation sequencing was 100% vs 79% (95% CI, 47%-94%; P < .001) and 100% vs 95% (95% CI, 75%-99%; P = .02), respectively. CONCLUSIONS AND RELEVANCE Carfilzomib-lenalidomide-dexamethasone therapy is tolerable and demonstrates high rates of MRD negativity in NDMM, translating into longer progression-free survival in patients achieving MRD negativity. Carfilzomib-lenalidomide-dexamethasone therapy also demonstrates efficacy in high-risk SMM.

Second malignancies after multiple myeloma: from 1960s to 2010s

Based on small numbers, recent reports from 3 randomized trials have consistently demonstrated more hematologic malignancies in patients treated with lenalidomide as maintenance (vs placebo). This fact has prompted concern and highlighted the association between multiple myeloma and second malignancies. Furthermore, an excess of acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) after multiple myeloma has been known for over 4 decades. Most prior studies have been restricted because of small numbers of patients, inadequate follow-up, and limitations of ascertainment of second malignancies. Although the underlying biologic mechanisms of AML/MDS after multiple myeloma are unknown, treatment-related factors are presumed to be responsible. Recently, an excess risk of AML/MDS was found among 5652 patients with IgG/IgA (but not IgM) monoclonal gammopathy of undetermined significance, supporting a role for disease-related factors. Furthermore, there is evidence to suggest that polymorphisms in germline genes may contribute to a persons susceptibility to subsequent cancers, whereas the potential influence of environmental and behavioral factors remains poorly understood. This review discusses current knowledge regarding second malignancies after multiple myeloma and gives future directions for efforts designed to characterize underlying biologic mechanisms, with the goal to maximize survival and minimize the risk for second malignancies for individual patients.

Minimal residual disease in multiple myeloma: bringing the bench to the bedside

Outcomes for patients with multiple myeloma (MM) have improved substantially in the past decade, with improvements in both progression-free survival and overall survival. Many patients are now achieving a complete response to treatment, and consequently highly sensitive assays are needed for detection of minimal residual disease (MRD) in patients with MM. Results of multicolour flow cytometry and deep-sequencing studies suggest that among patients achieving a complete response, MRD-negative status is associated with significant improvements in progression-free survival and overall survival. Despite the increasing need for MRD testing in patients with MM, considerable heterogeneity in techniques for MRD detection hinders the clinical interpretation of their results. The criteria used to define MRD, strengths and weaknesses of the major types of tests (flow cytometry versus molecular testing), and the optimal sample type (bone marrow aspirate versus peripheral blood) are all unresolved dilemmas in MRD testing. This Review presents an overview of the various techniques for MRD detection in patients with MM. In addition, this article discusses challenges and opportunities for the routine use of MRD testing, possible future directions for clinical trials and implications for drug approval processes.

A phase II trial of pan-KIR2D blockade with IPH2101 in smoldering multiple myeloma

Natural killer (NK) cells are involved in immune surveillance of various malignancies, including multiple myeloma (MM).[1][1] IPH2101 is a fully human monoclonal antibody that blocks HLA-C binding KIR2D receptors (KIR2DL/DS-1, -2 -3) expressed on the surface of NK-cells, enhancing their cytotoxicity

Modeling progression risk for smoldering multiple myeloma: results from a prospective clinical study

Abstract The risk of progression to multiple myeloma (MM) from the precursor condition smoldering MM (SMM) varies considerably among individual patients. Reliable markers for progression to MM are vital to advance the understanding of myeloma precursor disease and for the development of intervention trials designed to delay/prevent MM. The Mayo Clinic and Spanish PETHEMA have proposed models to stratify patient risk based on clinical parameters. The aim of our study was to define the degree of concordance between these two models by comparing the distribution of patients with SMM classified as low, medium and high risk for progression. A total of 77 patients with SMM were enrolled in our prospective natural history study. Per study protocol, each patient was assigned risk scores based on both the Mayo and the Spanish models. The Mayo Clinic model identified 38, 35 and four patients as low, medium and high risk, respectively. The Spanish PETHEMA model classified 17, 22 and 38 patients as low, medium and high risk, respectively. There was significant discordance in overall patient risk classification (28.6% concordance) and in classifying patients as low versus high (p < 0.0001), low versus non-low (p = 0.0007) and high versus non-high (p < 0.0001) risk. There is a need for prospectively validated models to characterize individual patient risk of transformation to MM.

The Role of Diagnosis and Clinical Follow-up of Monoclonal Gammopathy of Undetermined Significance on Survival in Multiple Myeloma.

IMPORTANCE Multiple myeloma (MM) is consistently preceded by the precursor state, monoclonal gammopathy of undetermined significance (MGUS). The average annual risk of progression from MGUS to multiple myeloma is 0.5% to 1.0%. Current guidelines suggest life-long clinical follow-up of individuals diagnosed as having MGUS depending on risk stratification. The impact of diagnosing and conducting clinical follow-up of MGUS on MM survival is unclear. OBJECTIVE To estimate the impact of prior knowledge of MGUS diagnosis and comorbidities on MM survival. DESIGN, SETTING, AND PARTICIPANTS We conducted a population-based study including all patients with MM (MM patients) diagnosed in Sweden (n = 14,798) from 1976 to 2005 (with follow-up until 2007); 394 (2.7%) had previously been diagnosed as having MGUS. Information on comorbidities was gathered for all patients. We calculated survival rates from the time of MM diagnosis, comparing patients with vs those without prior knowledge of MGUS. Using Cox proportional hazards models, we calculated hazard ratios (HRs) and 95% CIs for risk factors for death. χ2 Tests were used to evaluate differences in comorbidities. EXPOSURES Prior knowledge of MGUS among MM patients. In a subanalysis, monoclonal (M)-protein concentration and type were used as exposure. MAIN OUTCOMES AND MEASURES Risk of death and comorbidities. RESULTS Patients with MM with prior knowledge of MGUS had significantly (HR, 0.86; 95% CI, 0.77-0.96; P < .01) better overall survival (median survival, 2.8 years) than MM patients without prior knowledge of MGUS (median survival, 2.1 years), although MM patients with (vs without) prior knowledge of MGUS had more comorbidities (P < .001). Among MM patients with prior knowledge of MGUS, low M-protein concentration (<0.5 g/dL) at MGUS diagnosis was associated with poorer MM survival (HR, 1.86; 95% CI, 1.13-3.04; P = .01). CONCLUSIONS AND RELEVANCE Patients with MM with prior knowledge of MGUS had better MM survival, suggesting that earlier treatment of MM leads to better survival. The observation that a low M-protein concentration at MGUS diagnosis was associated with poorer MM survival may reflect less frequent clinical follow-up. Our observations stress the importance of clinical follow-up in patients with MGUS, regardless of risk stratification.

Flow cytometric differentiation of abnormal and normal plasma cells in the bone marrow in patients with multiple myeloma and its precursor diseases

Flow cytometric (FC) enumeration of abnormal plasma cells (APCs) for diagnosis and prognostication of plasma cell dyscrasias (PCD) is challenging. We studied antigen expression in normal plasma cells (NPC) (N = 34) and APC in a series of unselected PCD (N = 59). NPC subpopulations often demonstrated CD19(-), CD20(+), CD45(-) or dim and CD56(+), an immunophenotype observed in PCD. However abnormal CD81 was only observed in APCs (APC detection sensitivity 95%; specificity 100%). We evaluated differences in antigen expression patterns among MGUS (N = 14), SMM (N = 35) and MM (N = 10), finding the combination of CD45 and CD56 helpful in differentiating MGUS from SMM and MM (p = 0.0002).

Checkpoint Inhibition of KIR2D with the Monoclonal Antibody IPH2101 Induces Contraction and Hyporesponsiveness of NK-cells in Patients with Myeloma

Purpose: Immune checkpoint inhibitors have recently revolutionized cancer immunotherapy. On the basis of data showing KIR-ligand mismatched natural killer (NK) cells reduce the risk of leukemia and multiple myeloma relapse following allogeneic hematopoietic stem cell transplantation, investigators have developed a checkpoint inhibition antibody that blocks KIR on NK cells. Although in vitro studies suggest the KIR2D-specific antibody IPH2101 induces KIR-ligand mismatched tumor killing by NK cells, our single-arm phase II clinical trial in patients with smoldering multiple myeloma was prematurely terminated due to lack of clinical efficacy. This study aimed at unveiling the underlying mechanisms behind the lack of clinical efficacy. Experimental Design: Treatment-naïve patients received an intravenous infusion of 1 mg/kg IPH2101 every other month for up to a year. Peripheral blood was collected at baseline and 24 hours after first infusion, followed by weekly samples for the first month and monthly samples thereafter. NK cell phenotype and function was analyzed using high-resolution flow cytometry. Results: Unexpectedly, infusion of IPH2101 resulted in rapid reduction in both NK cell responsiveness and KIR2D expression on the NK cell surface. In vitro assays revealed KIR2D molecules are removed from the surface of IPH2101-treated NK cells by trogocytosis, with reductions in NK cell function directly correlating with loss of free KIR2D surface molecules. Although IPH2101 marginally augmented the antimyeloma cytotoxicity of remaining KIR2Ddull patient NK cells, the overall response was diminished by significant contraction and reduced function of KIR2D-expressing NK cells. Conclusions: These data raise concerns that the unexpected biological events reported in this study could compromise antibody-based strategies designed at augmenting NK cell tumor killing via checkpoint inhibition. Clin Cancer Res; 22(21); 5211–22. ©2016 AACR. See related commentary by Felices and Miller, p. 5161