Long-term follow-up of MRC Myeloma IX trial: Survival outcomes with bisphosphonate and thalidomide treatment

Thalidomide maintenance therapy in Japanese myeloma patients: a multicenter, phase II clinical trial (COMET study)

A prospective, multicenter, phase II study was performed to assess the efficacy and safety of thalidomide maintenance therapy at different doses in Japanese multiple myeloma (MM) patients. This study included 34 patients (median age, 74 years) who were previously treated with not more than three prior therapies and whose response status was evaluated as at least stable disease. They were randomized into Group A (no maintenance; 12 patients), Group B (50 mg thalidomide maintenance; 12 patients), and Group C (100 mg thalidomide maintenance; 10 patients), respectively. Thalidomide maintenance therapy resulted in improved depth of response in three cases (13.6%) and sustained response after induction therapy in eight cases (36.4%). Two-year progression-free survival (PFS) was 25.0%, 33.3%, and 77.8% in Groups A, B, and C, respectively, and was significantly higher in Group C than in Group A (p = 0.005). There was no difference in the incidence of hematological or non-hematological adverse events between Groups B and C. The current study demonstrates that maintenance with daily thalidomide at 100 mg, but not 50 mg, improved depth of response and prolonged PFS, and that this treatment was feasible for use in Japanese MM patients.

Lenalidomide maintenance versus observation for patients with newly diagnosed multiple myeloma (Myeloma XI): a multicentre, open-label, randomised, phase 3 trial

BACKGROUND

Patients with multiple myeloma treated with lenalidomide maintenance therapy have improved progression-free survival, primarily following autologous stem-cell transplantation. A beneficial effect of lenalidomide maintenance therapy on overall survival in this setting has been inconsistent between individual studies. Minimal data are available on the effect of maintenance lenalidomide in more aggressive disease states, such as patients with cytogenetic high-risk disease or patients ineligible for transplantation. We aimed to assess lenalidomide maintenance versus observation in patients with newly diagnosed multiple myeloma, including cytogenetic risk and transplantation status subgroup analyses.

METHODS

The Myeloma XI trial was an open-label, randomised, phase 3, adaptive design trial with three randomisation stages done at 110 National Health Service hospitals in England, Wales, and Scotland. There were three potential randomisations in the study: induction treatment (allocation by transplantation eligibility status); intensification treatment (allocation by response to induction therapy); and maintenance treatment. Here, we report the results of the randomisation to maintenance treatment. Eligible patients for maintenance randomisation were aged 18 years or older and had symptomatic or non-secretory multiple myeloma, had completed their assigned induction therapy as per protocol and had achieved at least a minimal response to protocol treatment, including lenalidomide. Patients were randomly assigned (1:1 from Jan 13, 2011, to Jun 27, 2013, and 2:1 from Jun 28, 2013, to Aug 11, 2017) to lenalidomide maintenance (10 mg orally on days 1-21 of a 28-day cycle) or observation, and stratified by allocated induction and intensification treatment, and centre. The co-primary endpoints were progression-free survival and overall survival, analysed by intention to treat. Safety analysis was per protocol. This study is registered with the ISRCTN registry, number ISRCTN49407852, and clinicaltrialsregister.eu, number 2009-010956-93, and has completed recruitment.

FINDINGS

Between Jan 13, 2011, and Aug 11, 2017, 1917 patients were accrued to the maintenance treatment randomisation of the trial. 1137 patients were assigned to lenalidomide maintenance and 834 patients to observation. After a median follow-up of 31 months (IQR 18-50), median progression-free survival was 39 months (95% CI 36-42) with lenalidomide and 20 months (18-22) with observation (hazard ratio [HR] 0·46 [95% CI 0·41-0·53]; p<0·0001), and 3-year overall survival was 78·6% (95% Cl 75·6-81·6) in the lenalidomide group and 75·8% (72·4-79·2) in the observation group (HR 0·87 [95% CI 0·73-1·05]; p=0·15). Progression-free survival was improved with lenalidomide compared with observation across all prespecified subgroups. On prespecified subgroup analyses by transplantation status, 3-year overall survival in transplantation-eligible patients was 87·5% (95% Cl 84·3-90·7) in the lenalidomide group and 80·2% (76·0-84·4) in the observation group (HR 0·69 [95% CI 0·52-0·93]; p=0·014), and in transplantation-ineligible patients it was 66·8% (61·6-72·1) in the lenalidomide group and 69·8% (64·4-75·2) in the observation group (1·02 [0·80-1·29]; p=0·88). By cytogenetic risk group, in standard-risk patients, 3-year overall survival was 86·4% (95% CI 80·0-90·9) in the lenalidomide group compared with 81·3% (74·2-86·7) in the observation group, and in high-risk patients, it was 74.9% (65·8-81·9) in the lenalidomide group compared with 63·7% (52·8-72·7) in the observation group; and in ultra-high-risk patients it was 62·9% (46·0-75·8) compared with 43·5% (22·2-63·1). Since these subgroup analyses results were not powered they should be interpreted with caution. The most common grade 3 or 4 adverse events for patients taking lenalidomide were haematological, including neutropenia (362 [33%] patients), thrombocytopenia (72 [7%] patients), and anaemia (42 [4%] patients). Serious adverse events were reported in 494 (45%) of 1097 patients receiving lenalidomide compared with 150 (17%) of 874 patients on observation. The most common serious adverse events were infections in both the lenalidomide group and the observation group. 460 deaths occurred during maintenance treatment, 234 (21%) in the lenalidomide group and 226 (27%) in the observation group, and no deaths in the lenalidomide group were deemed treatment related.

INTERPRETATION

Maintenance therapy with lenalidomide significantly improved progression-free survival in patients with newly diagnosed multiple myeloma compared with observation, but did not improve overall survival in the intention-to-treat analysis of the whole trial population. The manageable safety profile of this drug and the encouraging results in subgroup analyses of patients across all cytogenetic risk groups support further investigation of maintenance lenalidomide in this setting.

FUNDING

Cancer Research UK, Celgene, Amgen, Merck, and Myeloma UK.

Role of the RANK/RANKL Pathway in Multiple Myeloma

Receptor activator of nuclear factor-kappa B (RANK) and its ligand, RANKL, are expressed in a variety of tissues throughout the body; their primary role is in the regulation of bone remodeling and development of the immune system. Consistent with these functions, evidence exists for a role of RANK/RANKL in all stages of tumorigenesis, from cell proliferation and carcinogenesis to epithelial-mesenchymal transition to neoangiogenesis and intravasation to metastasis to bone resorption and tumor growth in bone. Results from current studies also point to a role of RANK/RANKL signaling in patients with multiple myeloma, who have increased serum levels of soluble RANKL and an imbalance in RANKL and osteoprotegerin. Current therapies for patients with multiple myeloma demonstrate that RANKL may be released by tumor cells or osteoprogenitor cells. This article will review currently available evidence supporting a role for RANK/RANKL signaling in tumorigenesis, with a focus on patients with multiple myeloma.

Quality of life during and following sequential treatment of previously untreated patients with multiple myeloma: findings of the Medical Research Council Myeloma IX randomised study

In the Medical Research Council (MRC) Myeloma IX trial (ISRCTN684564111) patients were randomised to sodium clodronate or zoledronic acid and induction treatment: cyclophosphamide, vincristine, doxorubicin and dexamethasone (CVAD) or cyclophosphamide, thalidomide and dexamethasone (CTD) followed by autologous stem cell transplant (ASCT) in the intensive pathway; attenuated CTD or melphalan and prednisolone (MP) in the non-intensive pathway. Subsequent randomisation allocated patients to either thalidomide or observation. The European Organisation for Research and Treatment of Cancer (EORTC) quality of life (QoL) questionnaires, QLQ-C30 and QLQ-MY24, were administered at baseline, 3, 6 and 12 months and annually thereafter, enabling the effect of sequential treatment on patient-reported health-related QoL (HR-QoL) to be investigated. The protocol specified four subscales of interest: Pain, Fatigue, Global Health Status/Quality of Life and Physical Functioning at 3, 6 and 12 months that were compared using linear models. The intensive pathway showed significant differences in favour of CTD for Fatigue at 3 months and Physical Functioning at 12 months. The non-intensive pathway and maintenance phase reported significant differences at 3 months; Pain (improved with attenuated CTD) and Global Health status/Quality of Life (improved with observation). The improved outcomes in MRC Myeloma IX were accompanied by some beneficial and few detrimental effects on HR-QoL.

How I treat the young patient with multiple myeloma

The treatment landscape for multiple myeloma has been transformed by the introduction of novel agents, including immunomodulatory drugs, proteasome inhibitors, and monoclonal antibodies. These have been shown to be more effective and generally better tolerated than conventional chemotherapy, with their introduction into clinical practice leading to improved survival. Furthermore, a better understanding of disease biology, improved diagnostic criteria, and the development of sensitive and specific tools for disease prognostication have contributed to better outcome. Treatment in the younger patient can now be individualized based on host and disease features with enhanced monitoring of response and use of high-sensitivity techniques for evaluating residual disease. The current standard of care has been significantly enhanced by novel agents with a paradigm shift toward optional or delayed autologous stem cell transplant as a reasonable choice in selected patients. Conversely, extended treatment with induction of remission followed by maintenance strategies is now a standard of care, conferring prolonged disease control with more manageable toxicities in both the short and long term, as well as improved quality of life.

Possible targets to treat myeloma-related osteoclastogenesis

INTRODUCTION

Bone destruction is the hallmark of multiple myeloma (MM). About 80% of MM patients at diagnosis presents myeloma bone disease (MBD) leading to bone pain and pathological fractures, significantly affecting patients' quality of life. Bisphosphonates are the treatment of choice for MBD, but osteolytic lesions remain a critical issue in the current management of MM patients. Several studies clarified the mechanisms involved in MM-induced osteoclast formation and activation, leading to the identification of new possible targets and the development of better bone-directed therapies, that are discussed in this review. Areas covered: This review summarizes the latest advances in the knowledge of the pathophysiology of the osteoclast formation and activation induced by MM cells, and the new therapeutic targets identified. Recently, neutralizing antibodies (i.e. denosumab, siltuximab, daratumumab), as well as recombinant fusion proteins, and receptor molecular inhibitors, have been developed to block these targets. Clinical trials testing their anti-MBD potential are ongoing. The emerging role of exosomes and microRNAs in the regulation of osteoclast differentiation has been also discussed. Expert commentary: Although further studies are needed to arrive at a clinical approving, the basis for the development of better bone-directed therapies has been established.

New agents in the Treatment of Myeloma Bone Disease

Patients with multiple myeloma develop a devastating bone disease driven by the uncoupling of bone remodelling, excess osteoclastic bone resorption and diminished osteoblastic bone formation. The bone phenotype is typified by focal osteolytic lesions leading to pathological fractures, hypercalcaemia and other catastrophic bone events such as spinal cord compression. This causes bone pain, impaired functional status, decreased quality of life and increased mortality. Early in the disease, malignant plasma cells occupy a niche environment that encompasses their interaction with other key cellular components of the bone marrow microenvironment. Through these interactions, osteoclast-activating factors and osteoblast inhibitory factors are produced, which together uncouple the dynamic process of bone remodelling, leading to net bone loss and focal osteolytic lesions. Current management includes antiresorptive therapies, i.e. bisphosphonates, palliative support and orthopaedic interventions. Bisphosphonates are the mainstay of treatment for myeloma bone disease (MBD), but are only partially effective and do have some significant disadvantages; for example, they do not lead to the repair of existing bone destruction. Thus, newer agents to prevent bone destruction and also promote bone formation and repair existing lesions are warranted. This review summarises novel ways that MBD is being therapeutically targeted.

Bisphosphonates in multiple myeloma: an updated network meta-analysis

BACKGROUND

Bisphosphonates are specific inhibitors of osteoclastic activity and are used in the treatment of patients with multiple myeloma (MM). While bisphosphonates are shown to be effective in reducing vertebral fractures and pain, their role in improving overall survival (OS) remains unclear. This is an update of a Cochrane review first published in 2002 and previously updated in 2010 and 2012.

OBJECTIVES

To assess the evidence related to benefits and harms associated with use of various types of bisphosphonates (aminobisphosphonates versus non-aminobisphosphonates) in the management of patients with MM. Our primary objective was to determine whether adding bisphosphonates to standard therapy in MM improves OS and progression-free survival (PFS), and decreases skeletal-related morbidity. Our secondary objectives were to determine the effects of bisphosphonates on pain, quality of life, incidence of hypercalcemia, incidence of bisphosphonate-related gastrointestinal toxicities, osteonecrosis of jaw (ONJ) and hypocalcemia.

SEARCH METHODS

We searched MEDLINE, Embase (September 2011 to July 2017) and the CENTRAL (2017, Issue 7) to identify all randomized controlled trial (RCT) in MM up to July 2017 using a combination of text and MeSH terms.

SELECTION CRITERIA

Any randomized controlled trial (RCT) comparing bisphosphonates versus placebo/no treatment/bisphosphonates and observational studies or case reports examining bisphosphonate-related ONJ in patients with MM were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors extracted the data. Data were pooled and reported as hazard ratio (HR) or risk ratio (RR) using a random-effects model. We used meta-regression to explore statistical heterogeneity. Network meta-analysis using Bayesian approach was conducted.

MAIN RESULTS

In this update, we included four new studies (601 participants), resulting in a total of 24 included studies.Twenty RCTs compared bisphosphonates with either placebo or no treatment and four RCTs involved another bisphosphonate as a comparator. The 24 included RCTs enrolled 7293 participants. Pooled results showed that there was moderate-quality evidence of a reduction in mortality with on OS from 41% to 31%, but the confidence interval is consistent with a larger reduction and small increase in mortality compared with placebo or no treatment (HR 0.90, 95% CI 0.76 to 1.07; 14 studies; 2706 participants). There was substantial heterogeneity among the included RCTs (I2 = 65%) for OS. To explain this heterogeneity we performed a meta-regression assessing the relationship between bisphosphonate potency and improvement in OS, which found an OS benefit with zoledronate but limited evidence of an effect on PFS. This provided a further rationale for performing a network meta-analyses of the various types of bisphosphonates that were not compared head-to-head in RCTs. Results from network meta-analyses showed evidence of a benefit for OS with zoledronate compared with etidronate (HR 0.56, 95% CI 0.29 to 0.87) and placebo (HR 0.67, 95% CI 0.46 to 0.91). However, there was no evidence for a difference between zoledronate and other bisphosphonates.The effect of bisphosphonates on disease progression (PFS) is uncertain. Based on the HR of 0.75 (95% CI 0.57 to 1.00; seven studies; 908 participants), 47% participants would experience disease progression without treatment compared with between 30% and 47% with bisphosphonates (low-quality evidence). There is probably a similar risk of non-vertebral fractures between treatment groups (RR 1.03, 95% CI 0.68 to 1.56; six studies; 1389 participants; moderate-quality evidence). Pooled analysis demonstrated evidence for a difference favoring bisphosphonates compared with placebo or no treatment on prevention of pathological vertebral fractures (RR 0.74, 95% CI 0.62 to 0.89; seven studies; 1116 participants; moderate-quality evidence) and skeletal-related events (SREs) (RR 0.74, 95% CI 0.63 to 0.88; 10 studies; 2141 participants; moderate-quality evidence). The evidence for less pain with bisphosphonates was of very low quality (RR 0.75, 95% CI 0.60 to 0.95; eight studies; 1281 participants).Bisphosphonates may increase ONJ compared with placebo but the confidence interval is very wide (RR 4.61, 95% CI 0.99 to 21.35; P = 0.05; six studies; 1284 participants; low-quality evidence). The results from the network meta-analysis did not show any evidence for a difference in the incidence of ONJ (eight RCTs, 3746 participants) between bisphosphonates. Data from nine observational studies (1400 participants) reported an incidence of 5% to 51% with combination of pamidronate and zoledronate, 3% to 11% with zoledronate alone, and 0% to 18% with pamidronate alone.The pooled results showed no evidence for a difference in increase in frequency of gastrointestinal symptoms with the use of bisphosphonates compared with placebo or no treatment (RR 1.23, 95% CI 0.95 to 1.59; seven studies; 1829 participants; low-quality evidence).The pooled results showed no evidence for a difference in increase in frequency of hypocalcemia with the use of bisphosphonates compared with placebo or no treatment (RR 2.19, 95% CI 0.49 to 9.74; three studies; 1090 participants; low-quality evidence). The results from network meta-analysis did not show any evidence for differences in the incidence of hypocalcemia, renal dysfunction and gastrointestinal toxicity between the bisphosphonates used.

AUTHORS' CONCLUSIONS

Use of bisphosphonates in participants with MM reduces pathological vertebral fractures, SREs and pain. Bisphosphonates were associated with an increased risk of developing ONJ. For every 1000 participants treated with bisphosphonates, about one patient will suffer from the ONJ. We found no evidence of superiority of any specific aminobisphosphonate (zoledronate, pamidronate or ibandronate) or non-aminobisphosphonate (etidronate or clodronate) for any outcome. However, zoledronate was found to be better than placebo and first-generation bisposphonate (etidronate) in pooled direct and indirect analyses for improving OS and other outcomes such as vertebral fractures. Direct head-to-head trials of the second-generation bisphosphonates are needed to settle the issue if zoledronate is truly the most efficacious bisphosphonate currently used in practice.

Fixed duration vs continuous therapy in multiple myeloma

The introduction of new drugs with less severe toxicity profiles than those of conventional antimyeloma agents allowed the evaluation of continuous therapy compared with fixed duration therapy. In transplant-eligible patients, consolidation therapy with bortezomib or bortezomib-based regimens showed significant progression-free survival (PFS) benefit in cytogenetic standard-risk patients and to a lesser extent, high-risk patients. Continuous therapy with lenalidomide maintenance treatment after autologous stem cell transplantation resulted in a significant survival gain. In transplant noneligible patients, continuous lenalidomide-dexamethasone therapy improved survival over fixed duration melphalan-prednisone-thalidomide. The concept of prolonged treatment in elderly patients is supported by some other studies, but most of them revealed a gain in PFS only. Young patients with unfavorable prognosis show a greater willingness to accept long-term treatment, whereas the readiness to undergo such treatments and the benefits therefrom decline with increasing age and decreasing fitness, rendering fixed duration therapy a suitable option in elderly frail patients.

Osteonecrosis of the jaw and survival of patients with cancer: a nationwide cohort study in Denmark

Osteonecrosis of the jaw (ONJ) is an adverse effect of bone‐targeted therapies, which are used to prevent symptomatic skeletal events following bone malignancy. We examined the association between ONJ and survival among cancer patients treated with bone‐targeted agents. Using nationwide registries and databases in Denmark, we identified 184 cancer patients with incident ONJ between 2010 and 2015, and a comparison cohort of 1067 cancer patients without ONJ and with a history of hospital‐administered treatment with bisphosphonates or denosumab initiating from cancer diagnosis. At the date of confirmed ONJ diagnosis, the comparison cohort was matched to the ONJ patients on age, cancer site, year of cancer diagnosis, and stage at diagnosis. The patients were followed up for survival until emigration or 15 June 2016. We computed overall survival and estimated mortality rate ratios adjusted for sex, and for the presence of distant metastases and other comorbidity at start of follow‐up. A match was found for 149 of the 184 ONJ patients. The 1‐ and 3‐year survival among all 184 cancer patients with ONJ was 70% (95% confidence interval [CI]: 63%–76%) and 42% (95% CI: 34%–51%), respectively. Among the matched patients, ONJ was associated with an adjusted mortality rate ratio of 1.31 (95% CI: 1.01–1.71). ONJ was associated with reduced survival among cancer patients treated with bone‐targeted agents. ONJ may be a marker of advanced disease or of survival‐related lifestyle characteristics.

Outcomes of maintenance therapy with lenalidomide or bortezomib in multiple myeloma in the setting of early autologous stem cell transplantation

Post-transplant maintenance is widely used in multiple myeloma (MM); however, there is a lack of data on real-world outcomes. We have analyzed 577 patients with newly diagnosed MM undergoing early auto-transplantation between 2010 and 2015. A total of 341, 132 and 104 patients received no, lenalidomide (Len) or bortezomib (Bort) maintenance, respectively. Patients receiving Len or Bort maintenance had a higher incidence of high-risk cytogenetics by fluorescence in situ hybridization (31% (Len) vs 58% (Bort) vs 8% (No); P<0.001). Len maintenance led to a superior progression-free survival (PFS) compared with no maintenance (median, 37 vs 28 months, respectively; P=0.002; adjusted hazard ratio 0.48 (95% CI, 0.35-0.66)), including in subgroups with ISS stage III disease (median, 40 vs 24 months; P=0.008) and high-risk cytogenetics (median, 27 vs 16 months; P=0.032). Bort maintenance did not confer PFS benefit for the entire cohort, but improved PFS in the high-risk cytogenetic subgroup (median, 28 vs 16 months; P=0.035). Discontinuation due to toxicity was seen in 17 and 7% of patients receiving Len or Bort maintenance, respectively. Our results indicate that post-transplant maintenance with Len or Bort is well tolerated in clinical practice and improves PFS in high-risk subgroups of MM patients.

Differential Depth Sensing Reduces Cancer Cell Proliferation via Rho-Rac-Regulated Invadopodia

Bone, which is composed of a porous matrix, is one of the principal secondary locations for cancer. However, little is known about the effect of this porous microenvironment in regulating cancer cell proliferation. Here, we examine how the depth of the pores can transduce a mechanical signal and reduce the proliferation of noncancer breast epithelial cells (MCF-10A) and malignant breast cancer cells (MDA-MB-231 and MCF-7) using micrometer-scale topographic features. Interestingly, cells extend actin-rich protrusions, such as invadopodia, to sense the depth of the matrix pore and activate actomyosin contractility to decrease MCF-10A proliferation. However, in MDA-MB-231, depth sensing inactivates Rho-Rac-regulated actomyosin contractility and phospho-ERK signaling. Inhibiting contractility on this porous matrix using blebbistatin further reduces MDA-MB-231 proliferation. Our findings support the notion of mechanically induced dormancy through depth sensing, where invadopodia-mediated depth sensing can inhibit the proliferation of noncancer and malignant breast cancer cells through differential regulation of actomyosin contractility.

Prediction of outcome in newly diagnosed myeloma: a meta-analysis of the molecular profiles of 1905 trial patients

Robust establishment of survival in multiple myeloma (MM) and its relationship to recurrent genetic aberrations is required as outcomes are variable despite apparent similar staging. We assayed copy number alterations (CNA) and translocations in 1036 patients from the NCRI Myeloma XI trial and linked these to overall survival (OS) and progression-free survival. Through a meta-anlysis of these data with data from MRC Myeloma IX trial, totalling 1905 newly diagnosed MM patients (NDMM), we confirm the association of t(4;14), t(14;16), t(14;20), del(17p) and gain(1q21) with poor prognosis with hazard ratios (HRs) for OS of 1.60 (P=4.77 × 10^-7), 1.74 (P=0.0005), 1.90 (P=0.0089), 2.10 (P=8.86 × 10^-14) and 1.68 (P=2.18 × 10^-14), respectively. Patients with 'double-hit' defined by co-occurrence of at least two adverse lesions have an especially poor prognosis with HRs for OS of 2.67 (P=8.13 × 10^-27) for all patients and 3.19 (P=1.23 × 10^-18) for intensively treated patients. Using comprehensive CNA and translocation profiling in Myeloma XI we also demonstrate a strong association between t(4;14) and BIRC2/BIRC3 deletion (P=8.7 × 10^-15), including homozygous deletion. Finally, we define distinct sub-groups of hyperdiploid MM, with either gain(1q21) and CCND2 overexpression (P<0.0001) or gain(11q25) and CCND1 overexpression (P<0.0001). Profiling multiple genetic lesions can identify MM patients likely to relapse early allowing stratification of treatment.

Adipose, Bone, and Myeloma: Contributions from the Microenvironment

Researchers globally are working towards finding a cure for multiple myeloma (MM), a destructive blood cancer diagnosed yearly in ~750,000 people worldwide (Podar et al. in Expert Opin Emerg Drugs 14:99-127, 2009). Although MM targets multiple organ systems, it is the devastating skeletal destruction experienced by over 90 % of patients that often most severely impacts patient morbidity, pain, and quality of life. Preventing bone disease is therefore a priority in MM treatment, and understanding how and why myeloma cells target the bone marrow (BM) is fundamental to this process. This review focuses on a key area of MM research: the contributions of the bone microenvironment to disease origins, progression, and drug resistance. We describe some of the key cell types in the BM niche: osteoclasts, osteoblasts, osteocytes, adipocytes, and mesenchymal stem cells. We then focus on how these key cellular players are, or could be, regulating a range of disease-related processes spanning MM growth, drug resistance, and bone disease (including osteolysis, fracture, and hypercalcemia). We summarize the literature regarding MM-bone cell and MM-adipocyte relationships and subsequent phenotypic changes or adaptations in MM cells, with the aim of providing a deeper understanding of how myeloma cells grow in the skeleton to cause bone destruction. We identify avenues and therapies that intervene in these networks to stop tumor growth and/or induce bone regeneration. Overall, we aim to illustrate how novel therapeutic target molecules, proteins, and cellular mediators may offer new avenues to attack this disease while reviewing currently utilized therapies.

The varied distribution and impact of RAS codon and other key DNA alterations across the translocation cyclin D subgroups in multiple myeloma

We examined a set of 805 cases that underwent DNA sequencing using the FoundationOne Heme (F1H) targeted sequencing panel and gene expression profiling. Known and likely variant calls from the mutational data were analyzed for significant associations with gene expression defined translocation cyclin D (TC) molecular subgroups. The spectrum of KRAS, NRAS, and BRAF codon mutations varied across subgroups with NRAS mutations at Q61 codon being common in hyperdiploid (HRD) and t(11;14) myeloma while being rare in MMSET and MAF. In addition, the presence of RAS-RAF mutations was inversely associated with NFκB pathway activation in all subgroups excluding MAF. In the MMSET subgroup, cases with low FGFR3 expression frequently had RAS-RAF mutations. Conditional inference tree analysis determined that mutation and homozygous deletion of TP53, CDKN2C, and RB1 were key prognostic factors associated with adverse outcome in a non-relapse clinical setting. In conclusion, this study highlights the heterogeneity in the distribution and clinical outcomes of RAS codon and other mutations in multiple myeloma dependent upon primary molecular subgroup.

Overexpression of EZH2 in multiple myeloma is associated with poor prognosis and dysregulation of cell cycle control

Myeloma is heterogeneous at the molecular level with subgroups of patients characterised by features of epigenetic dysregulation. Outcomes for myeloma patients have improved over the past few decades except for molecularly defined high-risk patients who continue to do badly. Novel therapeutic approaches are, therefore, required. A growing number of epigenetic inhibitors are now available including EZH2 inhibitors that are in early-stage clinical trials for treatment of haematological and other cancers with EZH2 mutations or in which overexpression has been correlated with poor outcomes. For the first time, we have identified and validated a robust and independent deleterious effect of high EZH2 expression on outcomes in myeloma patients. Using two chemically distinct small-molecule inhibitors, we demonstrate a reduction in myeloma cell proliferation with EZH2 inhibition, which leads to cell cycle arrest followed by apoptosis. This is mediated via upregulation of cyclin-dependent kinase inhibitors associated with removal of the inhibitory H3K27me3 mark at their gene loci. Our results suggest that EZH2 inhibition may be a potential therapeutic strategy for the treatment of myeloma and should be investigated in clinical studies.

Prolonged Use of Zoledronic Acid (4 Years) Did Not Improve Outcome in Multiple Myeloma Patients

BACKGROUND

Bisphosphonates, especially zoledronic acid (ZA), show antitumor effects in multiple myeloma (MM) and other neoplasms. The standard time for ZA administration has been 2 years. However, with improvement in overall survival (OS) in MM with new agents, it unclear whether ZA could be administered for a prolonged time to improve OS.

PATIENTS AND METHODS

A total of 170 patients with untreated, symptomatic MM were randomly divided into a group to receive ZA for 4 years, with a control group to receive ZA for 2 years. All patients were treated with the same induction therapy and stem-cell transplantation.

RESULTS

Actuarial curves at 5 years, showed that progression-free survival was 75% (95% confidence interval [CI], 64%-82%) and OS was 68% (95% CI, 60%-76%) in the 4-year group, which was not statistically significantly different compared with the control group: 72% (95% CI, 62%-78%) and 68% (95% CI, 60%-75%; P = .67). However, the 4-year group showed reduced skeletal events (21% occurrence rate); this was statistically significant compared with the control group: 43% (P < .001).

CONCLUSION

Although ZA did not improve OS in patients with MM; it continued to be useful to reduce skeletal events, and thus improve better quality of life for patients.

Outcomes of Maintenance Therapy with Bortezomib after Autologous Stem Cell Transplantation for Patients with Multiple Myeloma

Comprehensive recommendations for maintenance therapy after autologous stem cell transplantation (ASCT) for patients with multiple myeloma (MM) have yet to be defined. Bortezomib has been utilized as maintenance therapy after ASCT, but data attesting to the safety and efficacy of this agent compared with lenalidomide in the post-ASCT setting are limited. Therefore, we retrospectively analyzed the outcomes of 102 patients with MM who received maintenance therapy with bortezomib after ASCT at Duke University's adult bone marrow transplant clinic between 2005 and 2015. Maintenance with bortezomib was initiated between 60 and 90 days after ASCT as a single agent 1.3 mg/m2 once every 2 weeks (n = 92) or in combination with lenalidomide (10 mg/day) (n = 10). The median age at ASCT was 64 (range, 31 to 78). Of the 99 patients with molecular data available, 42% had high-risk cytogenetics (including d17p, t(4;14), +1q, and t(14;16) by fluorescein in situ hybridization). Overall, 46% of patients experienced side effects from maintenance therapy, with 31% of all patients experiencing peripheral neuropathy. In total, 2% of patients required discontinuation of bortezomib maintenance because of adverse events. No secondary malignancies were reported from the therapy. The median progression-free survival (PFS) for patients receiving maintenance therapy with bortezomib after ASCT was 36.5 months (95% confidence interval [CI], 21.3 to not available) and median overall survival was 72.7 months (95% CI, 63.9 to not available). The PFS of patients with high-risk cytogenetics was not statistically significantly different from those with standard-risk cytogenetics, suggesting that maintenance with bortezomib may help overcome the impact of high-risk cytogenetics on early progression. These results indicate that maintenance therapy with bortezomib represents a safe, well-tolerated, and efficacious option for patients with high-risk cytogenetics, renal insufficiency, an inability to tolerate lenalidomide, or a previous history of another cancer.

Guidelines for screening and management of late and long-term consequences of myeloma and its treatment

A growing population of long-term survivors of myeloma is now accumulating the 'late effects' not only of myeloma itself, but also of several lines of treatment given throughout the course of the disease. It is thus important to recognise the cumulative burden of the disease and treatment-related toxicity in both the stable and active phases of myeloma, some of which is unlikely to be detected by routine monitoring. We summarise here the evidence for the key late effects in long-term survivors of myeloma, including physical and psychosocial consequences (in Parts 1 and 2 respectively), and recommend the use of late-effects screening protocols in detection and intervention. The early recognition of late effects and effective management strategies should lead to an improvement in the management of myeloma patients, although evidence in this area is currently limited and further research is warranted.

Optimal treatment strategies in myeloma: An argument against maintenance therapy after autologous stem cell transplantation

Despite continuing advancements in novel therapeutics for multiple myeloma (MM), high-dose therapy with autologous stem cell rescue continues to represent the standard approach to treat transplant-eligible, newly diagnosed patients. As the disease remains essentially incurable, and median progression-free survival (PFS) times after autologous transplant are measured in years and not decades, attempts to improve outcomes in the post-transplant setting have been extensive and commonly focused on a "maintenance" approach. Although multiple trials have demonstrated PFS advantages for a variety of maintenance strategies, it is our position that the potential risks outweigh the benefits of this approach and this should not be the standard of care outside of clinical trials.

Role of stem cell transplant and maintenance therapy in plasma cell disorders

Autologous stem cell transplant (ASCT) has been an important component of therapy for myeloma patients eligible for high-dose chemotherapy. Recent studies comparing early transplant to low-dose chemotherapy support the continued use of ASCT as consolidation following induction therapy, even in the era of immunomodulatory drugs, proteasome inhibitors, and other novel agents. Despite the marked improvements in outcomes with this approach, most patients will eventually experience disease progression. Thus, inclusion of post-ASCT consolidation/maintenance strategies is used to improve long-term disease control. Multiple randomized studies support the use of lenalidomide maintenance therapy following ASCT. The next generation of clinical trials will incorporate novel agents such as monoclonal antibodies, proteasome inhibitors, and other novel pathway modulatory agents into post-ASCT treatment strategies with the goal of achieving even deeper responses and longer durations of disease control.

Role of stem cell transplant and maintenance therapy in plasma cell disorders

Autologous stem cell transplant (ASCT) has been an important component of therapy for myeloma patients eligible for high-dose chemotherapy. Recent studies comparing early transplant to low-dose chemotherapy support the continued use of ASCT as consolidation following induction therapy, even in the era of immunomodulatory drugs, proteasome inhibitors, and other novel agents. Despite the marked improvements in outcomes with this approach, most patients will eventually experience disease progression. Thus, inclusion of post-ASCT consolidation/maintenance strategies is used to improve long-term disease control. Multiple randomized studies support the use of lenalidomide maintenance therapy following ASCT. The next generation of clinical trials will incorporate novel agents such as monoclonal antibodies, proteasome inhibitors, and other novel pathway modulatory agents into post-ASCT treatment strategies with the goal of achieving even deeper responses and longer durations of disease control.

Oral ixazomib maintenance therapy in multiple myeloma

Continuous therapy has proven to be an effective therapeutic strategy to improve the outcome of both young and elderly multiple myeloma patients. Remarkably, lenalidomide and bortezomib showed to play a crucial role in this setting due to their safety profile allowing long-term exposure. Ixazomib, the first oral proteasome inhibitor to be evaluated in multiple myeloma, exerts substantial anti-myeloma activity as a single agent and particularly in combination with immunomodulatory drugs and it may be an attractive option for maintenance therapy. Here we address the issue of maintenance therapy as part of a therapeutic approach of multiple myeloma patients focusing on the potential role of ixazomib.

Genome-wide association study identifies multiple susceptibility loci for multiple myeloma

Multiple myeloma (MM) is a plasma cell malignancy with a significant heritable basis. Genome-wide association studies have transformed our understanding of MM predisposition, but individual studies have had limited power to discover risk loci. Here we perform a meta-analysis of these GWAS, add a new GWAS and perform replication analyses resulting in 9,866 cases and 239,188 controls. We confirm all nine known risk loci and discover eight new loci at 6p22.3 (rs34229995, P=1.31 × 10(-8)), 6q21 (rs9372120, P=9.09 × 10(-15)), 7q36.1 (rs7781265, P=9.71 × 10(-9)), 8q24.21 (rs1948915, P=4.20 × 10(-11)), 9p21.3 (rs2811710, P=1.72 × 10(-13)), 10p12.1 (rs2790457, P=1.77 × 10(-8)), 16q23.1 (rs7193541, P=5.00 × 10(-12)) and 20q13.13 (rs6066835, P=1.36 × 10(-13)), which localize in or near to JARID2, ATG5, SMARCD3, CCAT1, CDKN2A, WAC, RFWD3 and PREX1. These findings provide additional support for a polygenic model of MM and insight into the biological basis of tumour development.

Bone metastasis: the importance of the neighbourhood

During the past decade preclinical studies have defined many of the mechanisms used by tumours to hijack the skeleton and promote bone metastasis. This has led to the development and widespread clinical use of bone-targeted drugs to prevent skeletal-related events. This understanding has also identified a critical dependency between colonizing tumour cells and the cells of bone. This is particularly important when tumour cells first arrive in bone, adapt to their new microenvironment and enter a long-lived dormant state. In this Review, we discuss the role of different bone cell types in supporting disseminated tumour cell dormancy and reactivation, and highlight the new opportunities this provides for targeting the bone microenvironment to control dormancy and bone metastasis.

Management of multiple myeloma in older adults: Gaining ground with geriatric assessment

Multiple myeloma increases in incidence with age. With the aging of the population, the number of cases of multiple myeloma diagnosed in older adults each year will nearly double in the next 20years. The novel therapeutic agents have significantly improved survival in older adults, but their outcomes remain poorer than in younger patients. Older adults may be more vulnerable to toxicity of therapy, resulting in decreased dose intensity and contributing to poorer outcomes. Data are beginning to emerge to aid in identifying which individuals are at greater risk for toxicity of therapy; comorbidities, functional limitations, and age over 80years are among the factors associated with greater risk. Geriatric assessment holds promise in the care of older adults with multiple myeloma, both to allow modification of treatment to prevent toxicity, and to identify vulnerabilities that may require intervention. Emerging treatments with low toxicity and attention to individualizing therapy based on geriatric assessment may aid in further improving outcomes in older adults with multiple myeloma.

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

In a multicenter, randomized phase 3 trial, MPR-R was not superior over MPT-T with respect to response rate, PFS, and OS. Grade 3/4 hematologic toxicity requiring growth factor support occurred with MPR-R vs clinically significant neuropathy with MPT-T.

Genome-wide association study identifies variation at 6q25.1 associated with survival in multiple myeloma

Survival following a diagnosis of multiple myeloma (MM) varies between patients and some of these differences may be a consequence of inherited genetic variation. In this study, to identify genetic markers associated with MM overall survival (MM-OS), we conduct a meta-analysis of four patient series of European ancestry, totalling 3,256 patients with 1,200 MM-associated deaths. Each series is genotyped for ∼600,000 single nucleotide polymorphisms across the genome; genotypes for six million common variants are imputed using 1000 Genomes Project and UK10K as the reference. The association between genotype and OS is assessed by Cox proportional hazards model adjusting for age, sex, International staging system and treatment. We identify a locus at 6q25.1 marked by rs12374648 associated with MM-OS (hazard ratio=1.34, 95% confidence interval=1.22-1.48, P=4.69 × 10(-9)). Our findings have potential clinical implications since they demonstrate that inherited genotypes can provide prognostic information in addition to conventional tumor acquired prognostic factors.

Management of Transplant-Eligible Patients with Newly Diagnosed Multiple Myeloma

Treatment approaches for newly diagnosed myeloma have changed considerably during the past decade, along with a better understanding of the disease heterogeneity. Availability of new drug classes such as proteasome inhibitors and immunomodulatory drugs, and use of these drugs in combinations have led to higher response rates and deeper responses in the vast majority of patients with newly diagnosed myeloma. In addition to improved efficacy, these regimens are tolerated better than those with conventional chemotherapy drugs, which have reduced the early mortality seen in MM, while allowing for successful stem cell collection in patients undergoing stem cell transplant consolidation. Ongoing clinical trials with newer drugs such as monoclonal antibodies are being explored as options for newly diagnosed MM. The optimal regimen continues to evolve and is often dictated by the intent to transplant, age and comorbidities. Despite the increasing response rates seen with the new regimens, autologous stem cell transplantation remains an effective modality for consolidation, further deepening the responses seen with the initial therapy. Post-transplant approaches have further added to the efficacy of this platform with both post-transplant consolidation and maintenance demonstrating value in clinical trials. Currently, the combination of an effective initial therapy followed by one or two autologous stem cell transplants, with or without consolidation followed by maintenance appear to provide the maximum benefit in terms of duration of disease control for patients with newly diagnosed MM.

Treatment of Newly Diagnosed Elderly Multiple Myeloma

Multiple myeloma (MM) is a disease of the elderly, with a median age at diagnosis of approximately 70 years old, and more than 30 % of patients aged >75 years. This latter and very elderly population is going to significantly rise in the near future given the increase in life expectancy in Western countries, and, most importantly, global health status of elderly patients is improving, justifying appropriate treatments. Changes in treatment paradigm from the old melphalan-prednisone regimen used since the 1970s to its use as a backbone in a nontransplant setting since the late 1990s have highlighted different subgroups in elderly MM. Some "elderly" patients could be treated like transplant eligible patients, more likely those aged between 65 and the early 70; while a second group would rather be referred to current approved treatment regimens for the non-transplant setting. A dose-intensity approach seems reasonable for this group, aiming for the best response, eventually the complete response (CR) or even minimal residual disease (MRD). The advent of novel agents such as thalidomide, bortezomib, and most recently lenalidomide have allowed a major improvement in outcome as compared to historical combinations, and soon the novel class of monoclonal antibodies should help to further improve these patients' survival. Nonetheless, elderly patients are more susceptible to side effects and are often unable to tolerate full drug doses, and thus require lower dose intensity regimens, or novel drugs or combinations with more favourable safety profile. Recent developments in MM have focused on identifying these vulnerable patients through geriatric assessment and novel myeloma scoring system, including the notions of frailty, disability and comorbidities. Eventually, we have reached an era in which we should be able to provide individualized treatment strategies and drug doses-"tailored therapy"-to improve tolerability and optimize efficacy and ultimately survival for most elderly MM patients.

Bisphosphonates for cancer treatment: Mechanisms of action and lessons from clinical trials

A growing body of evidence points toward an important anti-cancer effect of bisphosphonates, a group of inexpensive, safe, potent, and long-term stable pharmacologicals that are widely used as osteoporosis drugs. To date, they are already used in the prevention of complications of bone metastases. Because the bisphosphonates can also reduce mortality in among other multiple myeloma, breast, and prostate cancer patients, they are now thoroughly studied in oncology. In particular, the more potent nitrogen-containing bisphosphonates have the potential to improve prognosis. The first part of this review will elaborate on the direct and indirect anti-tumoral effects of bisphosphonates, including induction of tumor cell apoptosis, inhibition of tumor cell adhesion and invasion, anti-angiogenesis, synergism with anti-neoplastic drugs, and enhancement of immune surveillance (e.g., through activation of γδ T cells and targeting macrophages). In the second part, we shed light on the current clinical position of bisphosphonates in the treatment of hematological and solid malignancies, as well as on ongoing and completed clinical trials investigating the therapeutic effect of bisphosphonates in cancer. Based on these recent data, the role of bisphosphonates is expected to further expand in the near future outside the field of osteoporosis and to open up new avenues in the treatment of malignancies.

Maintenance Therapy With Immunomodulatory Drugs in Multiple Myeloma: A Meta-Analysis and Systematic Review

BACKGROUND

Immunomodulatory drugs (IMiDs) and proteasome inhibitors have dramatically changed management of multiple myeloma (MM). While MM remains incurable, consolidation and maintenance therapy aimed at improving duration of response can potentially improve survival outcomes. A majority of randomized controlled trials (RCTs) have demonstrated benefit of IMiD-based maintenance therapy in delaying disease progression; however, whether this therapy can lead to improved survival remains controversial.

METHODS

PubMed and abstract databases of major hematology and/or oncology meetings were searched for RCTs that studied maintenance therapy with IMiDs in MM. A meta-analysis was conducted to systematically evaluate the impact of IMiD-based maintenance therapy on survival outcomes and serious adverse events associated with the therapy. All statistical tests were two-sided.

RESULTS

Eighteen phase 3 RCTs enrolling 7730 patients were included. IMiD-based maintenance therapy statistically significantly prolonged progression-free survival (PFS; hazard ratio (HR) = 0.62, 95% confidence interval (CI) = 0.57 to 0.67, P < .001) but failed to improve overall survival (OS; HR = 0.93, 95% CI = 0.85 to 1.01, P = .082). Stratified analyses demonstrated that both thalidomide and lenalidomide provided PFS but not OS benefit in transplantation as well as nontransplantation settings. IMiD-based maintenance therapy in MM led to a higher risk of grade 3-4 thromboembolism (risk ratio = 2.52, 95% CI = 1.41 to 4.52, P = .002). Thalidomide maintenance therapy increased the risk of peripheral neuropathy; lenalidomide maintenance therapy increased the risks of myelosuppression and second primary hematological malignancies.

CONCLUSIONS

Thalidomide- or lenalidomide-based maintenance therapy improves PFS but not OS in MM and increases risks of grade 3-4 adverse events, including thromboembolism, peripheral neuropathy, neutropenia, and infection.

Multiple Myeloma, Version 2.2016: Clinical Practice Guidelines in Oncology

Multiple myeloma (MM) is a malignant neoplasm of plasma cells that accumulate in bone marrow, leading to bone destruction and marrow failure. Recent statistics from the American Cancer Society indicate that the incidence of MM is increasing. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) included in this issue address management of patients with solitary plasmacytoma and newly diagnosed MM.

Bone antiresorptive agents in the treatment of bone metastases associated with solid tumours or multiple myeloma

Skeletal lesions contribute substantially to morbidity and mortality in patients with cancer. The disease manifestation course during metastatic bone disease is driven by tumour cells in the bone marrow, which alter the functions of bone-resorbing (osteoclasts) and bone-forming (osteoblasts) cells, promoting skeletal destruction. Successful therapeutic strategies for the treatment of metastatic bone disease include bisphosphonates and denosumab that inhibit osteoclast-mediated bone resorption. Inhibitors of cathepsin K, Src and activin A are under clinical investigation as potential anti-osteolytics. In this review, we describe current knowledge and future directions of antiresorptive therapies that may reduce or prevent destructive bone lesions from solid tumours and multiple myeloma.

Prediction of high- and low-risk multiple myeloma based on gene expression and the International Staging System

Patients with multiple myeloma have variable survival and require reliable prognostic and predictive scoring systems. Currently, clinical and biological risk markers are used independently. Here, International Staging System (ISS), fluorescence in situ hybridization (FISH) markers, and gene expression (GEP) classifiers were combined to identify novel risk classifications in a discovery/validation setting. We used the datasets of the Dutch-Belgium Hemato-Oncology Group and German-speaking Myeloma Multicenter Group (HO65/GMMG-HD4), University of Arkansas for Medical Sciences-TT2 (UAMS-TT2), UAMS-TT3, Medical Research Council-IX, Assessment of Proteasome Inhibition for Extending Remissions, and Intergroupe Francophone du Myelome (IFM-G) (total number of patients: 4750). Twenty risk markers were evaluated, including t(4;14) and deletion of 17p (FISH), EMC92, and UAMS70 (GEP classifiers), and ISS. The novel risk classifications demonstrated that ISS is a valuable partner to GEP classifiers and FISH. Ranking all novel and existing risk classifications showed that the EMC92-ISS combination is the strongest predictor for overall survival, resulting in a 4-group risk classification. The median survival was 24 months for the highest risk group, 47 and 61 months for the intermediate risk groups, and the median was not reached after 96 months for the lowest risk group. The EMC92-ISS classification is a novel prognostic tool, based on biological and clinical parameters, which is superior to current markers and offers a robust, clinically relevant 4-group model.