Mezigdomide plus Dexamethasone in Relapsed and Refractory Multiple Myeloma.

BACKGROUND: Despite recent progress, multiple myeloma remains incurable. Mezigdomide is a novel cereblon E3 ubiquitin ligase modulator with potent antiproliferative and tumoricidal activity in preclinical models of multiple myeloma, including those resistant to lenalidomide and pomalidomide. METHODS: In this phase 1-2 study, we administered oral mezigdomide in combination with dexamethasone to patients with relapsed and refractory myeloma. The primary objectives of phase 1 (dose-escalation cohort) were to assess safety and pharmacokinetics and to identify the dose and schedule for phase 2. In phase 2 (dose-expansion cohort), objectives included the assessment of the overall response (partial response or better), safety, and efficacy of mezigdomide plus dexamethasone at the dose and schedule determined in phase 1. RESULTS: In phase 1, a total of 77 patients were enrolled in the study. The most common dose-limiting toxic effects were neutropenia and febrile neutropenia. On the basis of the phase 1 findings, investigators determined the recommended phase 2 dose of mezigdomide to be 1.0 mg, given once daily in combination with dexamethasone for 21 days, followed by 7 days off, in each 28-day cycle. In phase 2, a total of 101 patients received the dose identified in phase 1 in the same schedule. All patients in the dose-expansion cohort had triple-class-refractory multiple myeloma, 30 patients (30%) had received previous anti-B-cell maturation antigen (anti-BCMA) therapy, and 40 (40%) had plasmacytomas. The most common adverse events, almost all of which proved to be reversible, included neutropenia (in 77% of the patients) and infection (in 65%; grade 3, 29%; grade 4, 6%). No unexpected toxic effects were encountered. An overall response occurred in 41% of the patients (95% confidence interval [CI], 31 to 51), the median duration of response was 7.6 months (95% CI, 5.4 to 9.5; data not mature), and the median progression-free survival was 4.4 months (95% CI, 3.0 to 5.5), with a median follow-up of 7.5 months (range, 0.5 to 21.9). CONCLUSIONS: The all-oral combination of mezigdomide plus dexamethasone showed promising efficacy in patients with heavily pretreated multiple myeloma, with treatment-related adverse events consisting mainly of myelotoxic effects. (Funded by Celgene, a Bristol-Myers Squibb Company; CC-92480-MM-001 ClinicalTrials.gov number, NCT03374085; EudraCT number, 2017-001236-19.).

Improved survival in myeloma patients-a nationwide registry study of 4,647 patients ≥75 years treated in Denmark and Sweden.

The prevalence of multiple myeloma (MM) is increasing in Nordic countries and the rest of the western world. Patients aged ≥75 years at diagnosis constitute an increasing proportion of all MM patients, but are underrepresented in randomized clinical trials. There is an urgent need for studies of the characteristics, treatment and outcome in this cohort. We present data from two nationwide population-based registries of all MM patients diagnosed in Denmark from January 1, 2005 until February 18, 2020, and in Sweden from January 1, 2008 until December 31, 2019, including treatment data for patients diagnosed until 2018 (Denmark) and 2019 (Sweden). In total 4,647 patients were ≥75 years at diagnosis, compared to 7,378 younger patients. Patients ≥75 years, accounting for approximately 40% of all MM patients, are a distinct cohort with more advanced disease at diagnosis, reflected by higher International Staging System (ISS) stage, and a higher proportion have renal failure and anemia. We found a more gradual introduction of modern medications in the older cohort than in the younger, despite simultaneous changes in guidelines. Compared to the cohorts in randomized controlled trials that guide the treatment of non-transplant eligible patients, we found a higher proportion of patients ≥75 years and presenting with ISS III in the real-world populations. Nevertheless, response rates and survival are increasing, indicating that modern treatment regimens are effective and well tolerated also in elderly MM patients in real-world populations.

The role of E3 ubiquitin ligase in multiple myeloma: potential for cereblon E3 ligase modulators in the treatment of relapsed/refractory disease.

INTRODUCTION: Insights into the mechanisms of protein homeostasis and proteasomal degradation have led to new strategies of redirecting the ubiquitin-proteasome system (UPS) to reduce or eliminate proteins or survival factors key to malignant pathobiology, multiple myeloma (MM) in particular. These strategies have enabled researchers to target proteins that were previously considered difficult to modulate by pharmacological means. AREAS COVERED: This review provides a brief overview of UPS biology, particularly the role of the CRL4CRBN E3 ubiquitin ligase complex, and summarizes current strategies for co-opting the UPS, including CELMoD compounds, SNIPERs, PROTACs, and degronimids. A detailed discussion is provided on lead CELMoD compounds iberdomide and mezigdomide, which are currently being evaluated in clinical trials in patients with MM. EXPERT OPINION: Since a high proportion of patients develop drug resistance, it is vital to have novel therapeutic agents for treating relapsed patients with MM more effectively. It is encouraging that the expanding pathophysiological insight into cellular signaling pathways in MM increasingly translates into the development of novel therapeutic agents such as targeted protein degraders. This holds promise for improving outcomes in MM and beyond.

Clinically-suspected cast nephropathy: A retrospective, national, real-world study.

Presentation with severe acute kidney injury due to cast nephropathy (CN) is a medical emergency in multiple myeloma (MM), with high risk of dialysis-dependent renal failure and death. Accrual of patients with CN into interventional studies is difficult, while phase III trials exclude patients with severe renal insufficiency. Real-world data are warranted. We assessed 2252 patients from the population-based Danish Multiple Myeloma Registry (DMMR) who were diagnosed between 2013 and 2017. We identified 204 patients with clinically-suspected CN, defined as serum creatinine concentration >177 µmol/L and serum free light chain (sFLC) concentration >1000 mg/L at the time of diagnosis. The median age was 72 years. Thirty-one percent of patients presented with dialysis-dependent renal failure. Kidney biopsies were performed in 19% of patients and showed CN in 74% of cases. Despite prompt initiation of bortezomib-based therapy in 94% of patients, 33% of patients died in the first year after diagnosis. Compared with the rest of the patients in the DMMR with symptomatic MM, patients with clinically-suspected CN had worse overall survival (OS) irrespective of transplant eligibility. Achievement of renal recovery was associated with deep reductions of involved sFLC. Achievement of very good partial response or better in the first line of therapy and/or deep reduction of involved sFLC at 3 months after initiation of therapy were associated with superior OS. In conclusion, MM patients presenting with clinically-suspected CN have an alarmingly high one-year mortality when treated with current standards of care. Early and deep hematologic response is crucial for survival.

Identification of miRSNPs associated with the risk of multiple myeloma.

Multiple myeloma (MM) is a malignancy of plasma cells usually infiltrating the bone marrow, associated with the production of a monoclonal immunoglobulin (M protein) which can be detected in the blood and/or urine. Multiple lines of evidence suggest that genetic factors are involved in MM pathogenesis, and several studies have identified single nucleotide polymorphisms (SNPs) associated with the susceptibility to the disease. SNPs within miRNA-binding sites in target genes (miRSNPs) may alter the strength of miRNA-mRNA interactions, thus deregulating protein expression. MiRSNPs are known to be associated with risk of various types of cancer, but they have never been investigated in MM. We performed an in silico genome-wide search for miRSNPs predicted to alter binding of miRNAs to their target sequences. We selected 12 miRSNPs and tested their association with MM risk. Our study population consisted of 1,832 controls and 2,894 MM cases recruited from seven European countries and Israel in the context of the IMMEnSE (International Multiple Myeloma rESEarch) consortium. In this population two SNPs showed an association with p < 0.05: rs286595 (located in gene MRLP22) and rs14191881 (located in gene TCF19). Results from IMMEnSE were meta-analyzed with data from a previously published genome-wide association study (GWAS). The SNPs rs13409 (located in the 3'UTR of the POU5F1 gene), rs1419881 (TCF19), rs1049633, rs1049623 (both in DDR1) showed significant associations with MM risk. In conclusion, we sought to identify genetic polymorphisms associated with MM risk starting from genome-wide prediction of miRSNPs. For some mirSNPs, we have shown promising associations with MM risk.

Smoldering multiple myeloma risk factors for progression: a Danish population-based cohort study.

Several risk scores for disease progression in patients with smoldering multiple myeloma (SMM) have been proposed; however, all have been developed using single-center registries. To examine risk factors for time to progression (TTP) to multiple myeloma (MM) for SMM, we analyzed a nationwide population-based cohort of 321 patients with newly diagnosed SMM registered within the Danish Multiple Myeloma Registry between 2005 and 2014. Significant univariable risk factors for TTP were selected for multivariable Cox regression analyses. We found that both an M-protein ≥30 g/L and immunoparesis significantly influenced TTP (HR 2.7, 95%CI (1.5;4.7), P = 0.001, and HR 3.3, 95%CI (1.4;7.8), P = 0.002, respectively). High free light chain (FLC) ratio did not significantly influence TTP in our cohort. Therefore, our data do not support recent IMWG proposal of identifying patients with FLC ratio above 100 as having ultra high-risk of transformation to MM. Using only immunoparesis and M-protein ≥30 g/L, we created a scoring system to identify low-, intermediate-, and high-risk SMM. This first population-based study of patients with SMM confirms that an M-protein ≥30 g/L and immunoparesis remain important risk factors for progression to MM.

Polymorphisms in the heparanase gene in multiple myeloma association with bone morbidity and survival.

OBJECTIVES: In multiple myeloma, heparanase (HSPE) is involved in myeloma cell growth, angiogenesis, osteoclastogenesis and shedding of syndecan-1, a key player in myeloma pathophysiology. Different single nucleotide polymorphisms (SNPs) in the HSPE gene with effect on gene function have been described, and some are associated with haematological malignancies. METHODS: In this study, we evaluated four SNPs rs11099592, rs4364254, rs4693608 and rs6535455 in the HSPE gene in 348 newly diagnosed multiple myeloma patients with focus on bone morbidity (lytic bone disease and vertebral fractures) and outcome after high-dose chemotherapy with stem cell support (HDT). RESULTS: We observed that homozygous carriers of the rs4693608 wild-type A-allele had a higher frequency of vertebral fractures compared to carriers of the variant G-allele, P = 0.02. In multivariate analysis, homozygous carriers of the rs6535455 variant T-allele had a longer survival than homo- and heterozygous carriers of the wild-type C-allele, hazard ratio 0.3 (95% CI 0.1-0.7, P = 0.002). CONCLUSION: The SNPs rs4693608 and rs6535455 in the HSPE gene may influence bone morbidity and outcome in multiple myeloma. Our results are an interesting observation but can be chance findings and need confirmation in studies exploring the functional role of SNPs in the HSPE gene in multiple myeloma.

Vascular endothelial growth factor (VEGF) gene polymorphisms may influence the efficacy of thalidomide in multiple myeloma.

Vascular endothelial growth factor (VEGF) is a potent proangiogenic factor. Several single nucleotide polymorphisms (SNPs) in the VEGF gene with influence on VEGF expression have been described. In multiple myeloma, VEGF stimulates angiogenesis which is correlated with disease progression and prognosis. In this study, we evaluated the association between genetic variations in the VEGF gene in patients with multiple myeloma and time to treatment failure (TTF) after high-dose melphalan and stem cell support (HDT), overall survival (OS) and efficacy of the anti-angiogenic drug thalidomide. Retrospectively, the SNPs -2,578C>A (rs699947), -460C>T (rs833061), +405G>C (rs2010963) and +936C>T (rs3025039) in the VEGF gene were examined in 348 patients with newly diagnosed multiple myeloma initially treated with HDT, where 176 patients were treated with thalidomide at relapse. None of the examined geno- or haplotypes was associated with differences in TTF after initial therapy or OS. A possible relation between the haplotype -2,578A/-460C/+405G (ACG) and effect of thalidomide was seen. Patients with no copies of the haplotype ACG had a longer time to next treatment than patients with one or two copies of the haplotype ACG, median 13.7 months vs. 9.2 months, p=0.007. In conclusion, the haplotype ACG in the VEGF gene may influence the efficacy of thalidomide in multiple myeloma. Further analyses are needed to confirm these findings and get insight into the functional effect of these polymorphisms, so in the future we may be able to select multiple myeloma patients who especially will benefit from treatment with thalidomide.

A functional polymorphism in the promoter region of the IL1B gene is associated with risk of multiple myeloma.

The cytokine interleukin-1ß (IL1B) is important for anti-tumour immune response. Genetic variation may modify the expression of IL1B and thereby influence the risk of disease. We investigated genetic variations with functional importance in the IL1B and NFKB1 genes in 348 population-based samples of multiple myeloma (MM) and a random sample of 1700 individuals. Carriers of the variant T-allele IL1B C-3737T and carriers of the TGT haplotype were at lower risk of MM [relative risk (RR) 0·58 (95% confidence interval (CI) = 0·41-0·84) and RR 0·59 (95%CI 0·40-0·85), respectively]. No association with risk of MM was found for the NFKB1- 94 ins/del polymorphism.

Single nucleotide polymorphisms in the promoter region of the IL1B gene influence outcome in multiple myeloma patients treated with high-dose chemotherapy independently of relapse treatment with thalidomide and bortezomib.

Little is known on the impact of polymorphisms in the IL1B gene on outcome in multiple myeloma. In a population-based study of 348 Danish myeloma patients treated with high-dose treatment (HDT), 146 patients treated with INF-α maintenance treatment, and in 243 patients with relapse, we analysed the impact on outcome of HDT, INF-α maintenance treatment, and treatment with thalidomide and bortezomib at relapse, in relation to the major identified functional polymorphisms in the promoter region of IL1B. The wild-type C-allele of IL1B C-3737T and non-carriage of the IL1B promoter haplotype TGT (-3737(T), -1464(G) and -31(T)), giving high IL1B promoter activity, were associated with longer time-to-treatment failure (TTF) (HR, 1.4 (1.0-1.9) and 1.5 (1.1-2.0)) and overall survival (HR, 1.8 (1.2-2.6) and 1.6 (1.1-2.3)) after HDT. Among INF-α treated patients, a trend towards better TTF was found in patients carrying the wild-type C-allele of IL1B C-3737T (HR, 1.6 (1.1-2.4)). Furthermore, among INF-α treated patients, gene-gene interaction studies on IL1B C-3737T and NFКB1-94ins/del ATTG revealed a fourfold increase in TTF for homozygous carriers of wild-type alleles at both loci as compared to variant allele carriers at both loci. No relation to genotype and outcome was found for relapse patients treated with thalidomide or bortezomib. Our results indicate that a subpopulation of myeloma patients carrying the wild-type C-allele of IL1B C-3737T and non-carriers of the promoter haplotype TGT (-3737(T), -1464(G) and -31(T)) benefit from a better outcome of HDT and INF-α treatment, an effect that may be related to the NF-κB pathway.

The importance of a sub-region on chromosome 19q13.3 for prognosis of multiple myeloma patients after high-dose treatment and stem cell support: a linkage disequilibrium mapping in RAI and CD3EAP.

The gene RAI was originally described as an inhibitor of RelA/p65 subunit of nuclear factor κB (NF-κB). Here, we analyse the association between genetic variation in the genes RAI and CD3EAP and outcome of 348 myeloma patients treated with high-dose treatment (HDT), 146 patients treated with interferon-α (INF-α) as maintenance treatment, 177 patients treated with thalidomide, and 74 patients treated with bortezomib at relapse and address if the effects of polymorphisms in CD3EAP and RAI are modified by a functional polymorphism in NFКB1. By linkage disequilibrium mapping, we found that variant alleles of several polymorphisms in a sub-region of 19q13.3 spanning the regions RAI-intron1-1 to RAI intron1-3 and the region exon1 to exon3­6 in CD3EAP were associated with prolonged time-to-treatment failure (TTF; p = 0.003) and overall survival (OS; p = 0.02). Haplotype analyses revealed that none of the haplotypes were more strongly associated to TTF or OS than the two strongly linked SNPs, RAI-intron1-1 (rs4572514) and CD3EAP G-21A (rs967591). The association of RAI-intron1-1 and CD3EAP G-21A with TTF was independent of NFKB1-94 ins/del, but homozygous ins-allele carriers which were also variant allele carriers of RAI-intron1-1 or CD3EAP G-21A had the longest OS. Among patients treated with INF-α or thalidomide, no effect was seen in relation to genotype. Our results indicate that polymorphism in RAI and CD3EAP are associated with outcome of myeloma patients treated with HDT. Combination analyses with the functional polymorphism in NFKB1 suggest that a possibly functional effect of RAI or CD3EAP could be related to NF-κB availability.

No influence of the polymorphisms CYP2C19 and CYP2D6 on the efficacy of cyclophosphamide, thalidomide, and bortezomib in patients with Multiple Myeloma.

BACKGROUND: The response to treatment varies among patients with multiple myeloma and markers for prediction of treatment outcome are highly needed. Bioactivation of cyclophosphamide and thalidomide, and biodegradation of bortezomib, is dependent on cytochrome P450 metabolism. We explored the potential influence of different polymorphisms in the CYP enzymes on the outcome of treatment. METHODS: Data was analyzed from 348 patients undergoing high-dose treatment and stem cell support in Denmark in 1994 to 2004. Clinical information on relapse treatment in 243 individual patients was collected. The patients were genotyped for the non-functional alleles CYP2C19*2 and CYP2D6*3, *4, *5 (gene deletion), *6, and CYP2D6 gene duplication. RESULTS: In patients who were treated with bortezomib and were carriers of one or two defective CYP2D6 alleles there was a trend towards a better time-to-next treatment. We found no association between the number of functional CYP2C19 and CYP2D6 alleles and outcome of treatment with cyclophosphamide or thalidomide. Neither was the number of functional CYP2C19 and CYP2D6 alleles associated with neurological adverse reactions to thalidomide and bortezomib. CONCLUSION: There was no association between functional CYP2C19 and CYP2D6 alleles and treatment outcome in multiple myeloma patients treated with cyclophosphamide, thalidomide or bortezomib. A larger number of patients treated with bortezomib are needed to determine the role of CYP2D6 alleles in treatment outcome.

Improved survival of multiple myeloma patients with late relapse after high-dose treatment and stem cell support, a population-based study of 348 patients in Denmark in 1994-2004.

OBJECTIVE: To analyse if patients with early relapse after high-dose chemotherapy with stem cell support (HDT) benefit from new treatment strategies in a population-based setting. METHODS: We conducted a retrospective study of relapse treatment and survival in 348 patients undergoing HDT in Denmark in 1994-2004. Patients were divided into two groups according to time-to-treatment failure (i) within 18 months after HDT and (ii) later than 18 months after HDT. The fraction of patients surviving 3 yr after first relapse was evaluated in relation to calendar periods for introduction of new drugs: before the introduction of thalidomide (1995-1999), before the introduction of bortezomib and lenalidomide (2000-2002) and when patients had access to all treatment modalities (2003-2008). RESULTS: Two hundred and forty-three patients suffered from relapse which required treatment. The median follow-up time was 91.4 months (60-158.8 months) and overall survival was 56.3 months after HDT. The fraction of patients alive 3 yr after first relapse increased in the periods after the year 2000 for patients with late relapse: 1995-1999, 36%; 2000-2002, 57%; and 2003-2008, 72% (P = 0.03), in contrast to patients with early relapse: 1995-1999, 25%; 2000-2002, 33%; and 2003-2008, 31% (P = 0.7). CONCLUSION: Improved survival was only observed among patients with late relapse after HDT and this may be because of increased use of salvage HDT, improved supportive care and introduction of new drugs.

Human P2X7 Receptor Causes Cycle Arrest in RPMI-8226 Myeloma Cells to Alter the Interaction with Osteoblasts and Osteoclasts.

Multiple myeloma is a malignant expansion of plasma cells and aggressively affects bone health. We show that P2X7 receptor altered myeloma growth, which affects primary bone cells in vitro. Expression on six human myeloma cell lines confirmed the heterogeneity associated with P2X7 receptor. Pharmacology with 2'(3')-O-(4-benzoylbenzoyl) adenosine 5'-triphosphate (BzATP) as agonist showed dose-dependent membranal pores on RPMI-8226 (p = 0.0027) and blockade with P2X7 receptor antagonists. Ca2+ influx with increasing doses of BzATP (p = 0.0040) was also inhibited with antagonists. Chronic P2X7 receptor activation reduced RPMI-8226 viability (p = 0.0208). No apoptosis or RPMI-8226 death was observed by annexin V/propidium iodide (PI) labeling and caspase-3 cleavage, respectively. However, bromodeoxyuridine (BrdU) labelling showed an accumulation of RPMI-8226 in the S phase of cell cycle progression (61.5%, p = 0.0114) with significant decline in G0/G1 (5.2%, p = 0.0086) and G2/M (23.5%, p = 0.0015) phases. As myeloma pathology depends on a positive and proximal interaction with bone, we show that P2X7 receptor on RPMI-8226 inhibited the myeloma-induced suppression on mineralization (p = 0.0286) and reversed the excessive osteoclastic resorption. Our results demonstrate a view of how myeloma cell growth is halted by P2X7 receptor and the consequences on myeloma-osteoblast and myeloma-osteoclast interaction in vitro.

A polymorphism in NFKB1 is associated with improved effect of interferon-{alpha} maintenance treatment of patients with multiple myeloma after high-dose treatment with stem cell support.

BACKGROUND: Maintenance therapy with interferon-alpha after high-dose treatment with stem cell support in multiple myeloma has been intensively debated. In this study, we evaluated the response to treatment with interferon-alpha in relation to genetic variation in genes related to inflammation. DESIGN AND METHODS: In a retrospective study of 296 patients with multiple myeloma undergoing high-dose therapy between 1994 and 2004, 146 patients were treated with interferon-alpha as maintenance therapy. We tested the polymorphisms IL1B T-31C, IL6 G-174C, NFKB1-94ins/delATTG, CD3EAP G-21A and PPP1R13L IVS1 A4364G for associations with time to treatment failure and overall survival with and without interferon-alpha treatment. RESULTS: The wild type ins-allele of polymorphism NFKB1-94 ins/delATTG was, by multivariate Cox analysis, associated with longer time to treatment failure (p=0.01) and overall survival (p=0.0084) when tested between treatment arms and in the subgroup of patients treated with interferon-alpha the wild type ins-allele was associated with longer overall survival (p=0.002). In the absence of interferon-alpha treatment, there was no association between the polymorphisms and treatment outcome, except for patients homozygous for the wild type G allele of IL6 G-174C who survived longer (p= 0.0074) than variant allele carriers. There was no association between the polymorphisms IL1B T-31C, CD3EAP G-21A and PPP1R13L IVS1 A4364G and treatment outcome for interferon-alpha. CONCLUSIONS: Patients who are homozygous carriers of the wild type ins-allele of the NFKB1 -94ins/delATTG polymorphism may benefit from treatment with interferon-alpha, in contrast to patients carrying the variant allele. This result may indicate that the effect of interferon-alpha treatment is dependent on the availability of nuclear factor-kappaB and the polymorphism in NFKB1 may, therefore, be a good prognostic marker for multiple myeloma patients on maintenance treatment with interferon-alpha after high-dose therapy. A prospective study of interferon-alpha treatment in relation to NFKB1 -94ins/delATTG is highly warranted.