Phase 1/2 study of lenalidomide combined with low-dose cyclophosphamide and prednisone in lenalidomide-refractory multiple myeloma

Metronomic chemotherapy in hematology: Lessons from preclinical and clinical studies to build a solid rationale for future schedules

Metronomic chemotherapy (mCHEMO), based on frequent, regular administration of low, but pharmacologically active drug doses, optimizes antitumor efficacy by targeting multiple targets and reducing toxicity of antineoplastic drugs. This minireview will summarize preclinical and clinical studies on cytotoxic drugs given at weekly, daily, or at continuous metronomic schedules alone or in combination with novel targeted agents for hematological malignancies, including lymphoma, multiple myeloma, and leukemia. Most of the preclinical in vitro and in vivo studies have reported a significant benefit of both mCHEMO monotherapy and combinatorial regimens compared with chemotherapy at the maximum tolerated dose. However, the combination of mCHEMO with targeted drugs is still little explored in the hematologic clinical setting. Data obtained from preclinical studies on low dose metronomic chemotherapy in hematological malignancies clearly suggested the possibility to clinically investigate more tolerable and effective strategies for the treatment of patients with advanced hematological malignancies, or at least for those frail and elderly patients, who are not eligible or resistant to standard treatments.

Outcomes of patients with multiple myeloma refractory to standard dose vs low dose lenalidomide

Refractoriness to lenalidomide is an important factor determining the choice of therapy at first relapse in multiple myeloma (MM). It remains debatable if resistance to lenalidomide varies among MM refractory to standard doses vs low dose maintenance doses. In this study, we assessed the outcomes with subsequent therapies in patients with MM refractory to standard dose vs low dose lenalidomide. We retrospectively reviewed all patients with MM at our institution who received first line therapy with lenalidomide containing regimens, and assessed progression free survival (PFS) and overall survival for these patients for second line therapy, and with lenalidomide retreatment. For second line therapy, we found no difference in the PFS between standard dose refractory and low dose refractory groups (median PFS 14 months vs 14 months, p = 0.95), while the PFS for both these groups was inferior to the not refractory group (median PFS 30 months, p < 0.001 for both pairs). Similar trends were seen among these groups on lenalidomide retreatment, and on multivariable analysis. These data suggest that refractoriness to lenalidomide is not dose dependent, and definition of lenalidomide refractoriness should not depend on the dose of lenalidomide to which the disease was considered refractory.

Evidence-based mechanisms of synergy with IMiD agent-based combinations in multiple myeloma

Treatment of multiple myeloma (MM) has seen great advances in recent years, and a key contributor to this change has been the effective use of combination therapies, which have improved both the depth and duration of patient responses. IMiD agents (lenalidomide and pomalidomide) have both tumoricidal and immunostimulatory functions, and due to their multiple mechanisms of action have become the backbone of numerous combination treatments in the newly diagnosed and relapsed/refractory settings. Although IMiD agent-based combination regimens provide improved clinical outcomes for patients with MM, the mechanisms underpinning these combinations are not well understood. In this review we describe the potential mechanisms of synergy leading to the enhanced activity observed when IMiD agents and other drug classes are used in combination through interrogation of the current knowledge surrounding their mechanism of actions.

Revisiting the Role of Alkylating Agents in Multiple Myeloma: Up-to-Date Evidence and Future Perspectives

From the 1960s to the early 2000s, alkylating agents (e.g., melphalan, cyclophosphamide, and bendamustine) remained a key component of standard therapy for newly-diagnosed or relapsed/refractory multiple myeloma (MM). Later on, their associated toxicities (including second primary malignancies) and the unprecedented efficacy of novel therapies have led clinicians to increasingly consider alkylator-free approaches. Meanwhile, new alkylating agents (e.g., melflufen) and new applications of old alkylators (e.g., lymphodepletion before chimeric antigen receptor T-cell [CAR-T] therapy) have emerged in recent years. Given the expanding use of antigen-directed modalities (e.g., monoclonal antibodies, bispecific antibodies, and CAR-T therapy), this review explores the current and future role of alkylating agents in different treatment settings (e.g., induction, consolidation, stem cell mobilization, pre-transplant conditioning, salvage, bridging, and lymphodepleting chemotherapy) to ellucidate the role of alkylator-based regimens in modern-day MM management.

Continuous low-dose cyclophosphamide plus prednisone in the treatment of relapsed and refractory multiple myeloma with severe complications

Background/objective

We retrospectively analyzed the effective and safety of continuous low-dose cyclophosphamide combined with prednisone (CP) in relapsed and refractory multiple myeloma (RRMM) patients with severe complications.

Methods

A total of 130 RRMM patients with severe complications were enrolled in this study, among which 41 patients were further given bortezomib, lenalidomide, thalidomide or ixazomib on the basis of CP regimen (CP+X group). The response to therapy, adverse events (AEs), overall survival (OS) and progression-free survival (PFS) were recorded.

Results

Among the 130 patients, 128 patients received therapeutic response assessment, with a complete remission rate (CRR) and objective response rate (ORR) of 4.7% and 58.6%, respectively. The median OS and PFS time were (38.0 ± 3.6) and (22.9±5.2) months, respectively. The most common AEs were hyperglycemia (7.7%), pneumonia (6.2%) and Cushing's syndrome (5.4%). In addition, we found the pro-BNP/BNP level was obviously decreased while the LVEF (left ventricular ejection fraction) was increased in RRMM patients following CP treatment as compared with those before treatment. Furthermore, CP+X regimen further improved the CRR compared with that before receiving the CP+X regimen (24.4% vs. 2.4%, P=0.007). Also, both the OS and PFS rates were significantly elevated in patients received CP+X regimen following CP regimen as compared with the patients received CP regimen only.

Conclusion

This study demonstrates the metronomic chemotherapy regimen of CP is effective to RRMM patients with severe complications.

Management of Relapsed-Refractory Multiple Myeloma in the Era of Advanced Therapies: Evidence-Based Recommendations for Routine Clinical Practice

Multiple myeloma (MM) is the second most common hematologic malignancy in adults worldwide. Over the past few years, major therapeutic advances have improved progression-free and overall survival, as well as quality of life. Despite this recent progress, MM remains incurable in the vast majority of cases. Patients eventually relapse and become refractory to multiple drug classes, making long-term management challenging. In this review, we will focus on the treatment paradigm of relapsed/refractory MM (RRMM) in the era of advanced therapies emphasizing the available novel modalities that have recently been incorporated into routine practice, such as chimeric antigen receptor T-cell therapy, bispecific antibodies, and other promising approaches. We will also discuss major factors that influence the selection of appropriate drug combinations or cellular therapies, such as relapse characteristics, and other disease and patient related parameters. Our goal is to provide insight into the currently available and experimental therapies for RRMM in an effort to guide the therapeutic decision-making process.

Ixazomib, Oral Metronomic Cyclophosphamide, and Dexamethasone for First-Line Treatment of Multiple Myeloma: A Phase II Brown University Oncology Group Study

BACKGROUND

Newly diagnosed multiple myeloma patients have many available treatment options. While lenalidomide, bortezomib, and dexamethasone (RVD) is the preferred initial treatment for many patients, several other agents may provide similar efficacy with less toxicity and improved ease of administration.

METHODS

We evaluated the safety and efficacy of the all-oral regimen of ixazomib, cyclophosphamide, and dexamethasone with the use of metronomic cyclophosphamide dosing in the treatment of patients with newly diagnosed multiple myeloma.

RESULTS

The study was stopped prior to planned enrollment due to slow recruitment, with 12 patients available for final analysis. The overall response rate was 58.3% with 2 patients achieving a very good partial response (16.7%) and 5 patients achieving a partial response (41.7%). Median progression-free survival was 16 months, and median overall survival was 43 months. There were no episodes of grade 3 or greater peripheral neuropathy. Grade 3 or greater dermatologic toxicity was experienced in 50% of patients.

CONCLUSION

Although limited enrollment prevented full efficacy evaluation, our data do not support further study of metronomic cyclophosphamide in combination with ixazomib and dexamethasone in the treatment of newly diagnosed multiple myeloma. The activity of this regimen in the relapsed/refractory setting requires further study (ClinicalTrials.gov Identifier: NCT02412228).

Relapsed/Refractory Multiple Myeloma: A Review of Available Therapies and Clinical Scenarios Encountered in Myeloma Relapse

Multiple myeloma remains an incurable disease with the usual disease course requiring induction therapy, autologous stem cell transplantation for eligible patients, and long-term maintenance. Risk stratification tools and cytogenetic alterations help inform individualized therapeutic choices for patients in hopes of achieving long-term remissions with preserved quality of life. Unfortunately, relapses occur at different stages of the course of the disease owing to the biological heterogeneity of the disease. Addressing relapse can be complex and challenging as there are both therapy- and patient-related factors to consider. In this broad scoping review of available therapies in relapsed/refractory multiple myeloma (RRMM), we cover the pharmacologic mechanisms underlying active therapies such as immunomodulatory agents (IMiDs), proteasome inhibitors (PIs), monoclonal antibodies (mAbs), traditional chemotherapy, and Venetoclax. We then review the clinical data supporting the use of these therapies, organized based on drug resistance/refractoriness, and the role of autologous stem cell transplant (ASCT). Approaches to special situations during relapse such as renal impairment and extramedullary disease are also covered. Lastly, we look towards the future by briefly reviewing the clinical data supporting the use of chimeric antigen receptor (CAR-T) therapy, bispecific T cell engagers (BITE), and Cereblon E3 Ligase Modulators (CELMoDs).

No needles needed: All-oral therapy options for relapsed and refractory multiple myeloma

Immense progress has been made for the treatment of multiple myeloma over the past two decades, with patient outcomes improving dramatically as a result. Patient quality of life, however, is constantly challenged by complications of the disease, side effects of therapy and the overall burden receiving continuous treatment. Compared to parenteral agents, all-oral regimens can provide logistically favorable alternatives and are associated with improved quality of life. Here, we review the currently available and investigational oral therapies for relapsed and refractory multiple myeloma and provide a practical clinical reference tool. We explore the factors that dictate the selection of therapy, such as prior drug refractoriness, disease biology and patient-specific considerations. Regimens with their respective supporting clinical data are organized by the degree of prior treatment, from lenalidomide-sensitive to heavily pretreated patients. We explore common challenges such as renal insufficiency and cytopenias. Lastly, we review investigational oral agents.

Combined ibrutinib and venetoclax for treatment of patients with ibrutinib-resistant or double-refractory chronic lymphocytic leukaemia

Patients with chronic lymphocytic leukaemia (CLL) disease progression on ibrutinib or after sequential ibrutinib and venetoclax-based treatments (double-refractory) have poor outcomes. In this retrospective study, we analysed outcomes with combined ibrutinib and venetoclax treatment in these groups of patients. The median treatment-free and overall survival for 22 patients with prior progression on ibrutinib (venetoclax-naïve) were 23.7 and 47.1 months respectively. In 11 patients with double-refractory CLL, the median treatment-free and overall survival were 11.2 and 27.0 months respectively. The combination of ibrutinib and venetoclax may help bridge the current gap in options for patients with disease refractory to the most commonly used novel agents.

Current Status of the Spectrum and Therapeutics of Helicobacter pylori-Negative Mucosa-Associated Lymphoid Tissue Lymphoma

Simple Summary

The prevalence of Helicobacter pylori (HP)-negative gastric mucosa-associated lymphoid tissue (MALT) lymphoma has increased over the last two decades, whereas that of HP-positive gastric MALT lymphoma has decreased. Although the role of first-line antibiotics in the treatment of HP-negative gastric MALT lymphomas remains ambiguous, several case series have reported that a first-line HP eradication therapy (HPE)-like regimen could result in complete remission in a proportion of patients with localized HP-negative gastric MALT lymphoma. Previous sporadic reports have indicated that certain patients with extragastric MALT lymphoma can respond to first-line antibiotic treatment as well. These findings suggest that, in contrast to antibiotic-unresponsive tumors, antibiotic-responsive tumors may be recognized within the spectrum of HP-negative MALT lymphoma. In addition to conventional chemotherapy and immunochemotherapy, macrolide antibiotics and immunomodulatory drugs have been previously used and demonstrated to be efficacious. This article provides the spectrum and therapeutics for HP-negative MALT lymphoma.

Abstract

Helicobacter pylori (HP)-unrelated mucosa-associated lymphoid tissue (MALT) lymphoma includes the majority of extragastric MALT lymphomas and a small proportion of gastric MALT lymphomas. Although the role of first-line antibiotics in treating HP-negative gastric MALT lymphomas remains controversial, HP eradication therapy (HPE)-like regimens may result in approximately 20–30% complete remission (CR) for patients with localized HP-negative gastric MALT lymphoma. In these patients, H. heilmannii, H. bizzozeronii, and H. suis were detected in sporadic gastric biopsy specimens. Extragastric MALT lymphoma is conventionally treated with radiotherapy for localized disease and systemic chemotherapy for advanced and metastatic diseases. However, a proportion of extragastric MALT lymphomas, such as ocular adnexal lesions and small intestinal lesions, were reported to be controlled by antibiotics for Chlamydophila psittaci and Campylobacter jejuni, respectively. Some extragastric MALT lymphomas may even respond to first-line HPE. These findings suggest that some antibiotic-responsive tumors may exist in the family of HP-negative MALT lymphomas. Two mechanisms underlying the antibiotic responsiveness of HP-negative MALT lymphoma have been proposed. First, an HPE-like regimen may eradicate the antigens of unknown bacteria. Second, clarithromycin (the main component of HPE) may have direct or indirect antineoplastic effects, thus contributing to the CR of these tumors. For antibiotic-unresponsive HP-negative MALT lymphoma, high-dose macrolides and immunomodulatory drugs, such as thalidomide and lenalidomide, have reported sporadic success. Further investigation of new treatment regimens is warranted.

Pomalidomide in Patients With Relapsed and/or Refractory Multiple Myeloma: A Prospective Study Within the Nationwide Netherlands Cancer Registry

Patients with relapsed and/or refractory multiple myeloma (RRMM) generally have limited treatment options and a poor prognosis. Previous trials demonstrated that pomalidomide combined with low-dose dexamethasone (Pd) is effective in these patients with significant responses and improved progression-free survival (PFS). Pd has been approved in RRMM patients who received ≥2 prior lines of therapy. Here, we present the results of a population-based study of patients with RRMM treated with Pd in The Netherlands from time of pomalidomide approval. Using the nationwide Netherlands Cancer Registry, data from all nontrial patients with RRMM treated with Pd were collected. Data were analyzed of response, PFS, and overall survival (OS). A total of 237 patients were included in this analysis. Previous treatment consisted of a proteasome inhibitor in 227 patients (96%) and/or an immune-modulating agent in 235 patients (99%). One hundred forty patients (59%) were refractory to an immune-modulating agent in their last line of therapy. Median time from diagnosis to treatment with Pd was 4.9 years (interquartile range, 2.7–7.9), and the median number of prior treatments was 4 (interquartile range, 3–5). Median PFS and OS for all patients were 3.6 months (95% confidence interval [CI], 3.1–3.8) and 7.7 months (95% CI, 5.7–9.7), respectively. For patients achieving ≥PR, median PFS and OS were 10.6 months (95% CI, 8.3–12.9) and 16.3 months (95% CI, 13.6–23.2), respectively. This nationwide, population-based registry study confirms data shown in pivotal clinical trials on Pd. PFS in this analysis is comparable to PFS observed in those clinical trials.

How I Treat Relapsed Multiple Myeloma

Despite recent advances multiple myeloma remains an incurable disease for most of the patients and initial remission will be followed by relapses requiring therapy. For many, there will be several remissions and relapses until resistance develops to all available therapies. With the introduction of several new agents, myeloma treatment has changed drastically and there are new options for the management of relapsed or refractory disease, including new drug classes with distinct mechanisms of action and cellular therapies. However, resistance to major drug classes used in first line remain the most critical factor for the choice of treatment at relapse. Continuous lenalidomide-based therapy is used extensively at first line and resistance to lenalidomide has become the key factor for the choice of salvage therapy. Daratumumab is increasingly used in first line and soon patients that relapse while on daratumumab will become a common challenge. Three-drug regimens are standard approach to manage relapsed disease. Adding drugs with new mechanisms of activity can improves outcomes and overcomes class resistance but, until now, while the biology is important, can offer only limited guidance for the choice of therapy.

Metronomic chemotherapy regimens and targeted therapies in non-Hodgkin lymphoma: The best of two worlds

Novel drugs are rapidly moving forward the treatment-paradigm of non-Hodgkin-lymphomas (NHLs). Notwithstanding, especially in aggressive subtypes, chemotherapy remains the pillar of treatment. Indeed, the combination of highly effective Maximum-Tolerated-Dose Chemotherapy (MTD-CHEMO) + "novel drugs", has so far, fallen short from expectations, often because it caused excessive toxicity. Metronomic chemotherapy (mCHEMO), which is the frequent, long-term administration of low dose cytotoxic drugs, may allow more effective and tolerable combinations. mCHEMO pharmacodynamics, has been described as pleiotropic. In fact, it may have different cellular and molecular targets, when drugs or their schedules are modified. Although mCHEMO has been little explored in NHLs, pre-clinical studies - in lymphoma models - which addressed the activity of mCHEMO in combination with novel drugs, have shown very promising results. These included inhibitors of histone deacetylase, mTOR and PI3K/mTOR, as well as the immune checkpoint inhibitor anti-PD-L1. Moreover, a few impressive reports have recently shown all-oral mCHEMO schedules, with or without rituximab, can effectively shrink both B and T-cell aggressive NHLs. Indeed, these regimens allowed elderly-frail patients to achieve sustained remission, while toxicity proved manageable. In our opinion, all-oral mCHEMO, is an active, easy-to start, well-tolerated, and inexpensive therapeutic approach, which deserves further investigation. Most importantly, mCHEMO, holds promise to empower the activity of novel targeted therapies, without causing excessive toxicity.

Harnessing the Immune System to Fight Multiple Myeloma

Multiple myeloma (MM) is a heterogeneous plasma cell malignancy differing substantially in clinical behavior, prognosis, and response to treatment. With the advent of novel therapies, many patients achieve long-lasting remissions, but some experience aggressive and treatment refractory relapses. So far, MM is considered incurable. Myeloma pathogenesis can broadly be explained by two interacting mechanisms, intraclonal evolution of cancer cells and development of an immunosuppressive tumor microenvironment. Failures in isotype class switching and somatic hypermutations result in the neoplastic transformation typical of MM and other B cell malignancies. Interestingly, although genetic alterations occur and evolve over time, they are also present in premalignant stages, which never progress to MM, suggesting that genetic mutations are necessary but not sufficient for myeloma transformation. Changes in composition and function of the immune cells are associated with loss of effective immune surveillance, which might represent another mechanism driving malignant transformation. During the last decade, the traditional view on myeloma treatment has changed dramatically. It is increasingly evident that treatment strategies solely based on targeting intrinsic properties of myeloma cells are insufficient. Lately, approaches that redirect the cells of the otherwise suppressed immune system to take control over myeloma have emerged. Evidence of utility of this principle was initially established by the observation of the graft-versus-myeloma effect in allogeneic stem cell-transplanted patients. A variety of new strategies to harness both innate and antigen-specific immunity against MM have recently been developed and intensively tested in clinical trials. This review aims to give readers a basic understanding of how the immune system can be engaged to treat MM, to summarize the main immunotherapeutic modalities, their current role in clinical care, and future prospects.

Current and Novel Alkylators in Multiple Myeloma

A large number of novel treatments for myeloma have been developed and approved; however, alkylating drugs continue to be part of standard regimens. Additionally, novel alkylators are currently being developed. We performed a non-systematized literary search for relevant papers and communications at large conferences, as well as exploiting the authors' knowledge of the field, to review the history, current use and novel concepts around the traditional alkylators cyclophosphamide, bendamustine and melphalan and current data on the newly developed pro-drug melflufen. Even in the era of targeted treatment and personalized medicine, alkylating drugs continue to be part of the standard-of-care in myeloma, and new alkylators are coming to the market.

Pomalidomide, Cyclophosphamide, and Dexamethasone for the Treatment of Relapsed/Refractory Multiple Myeloma: Real-World Analysis of the Pethema-GEM Experience

INTRODUCTION

Treatment of relapsed/refractory multiple myeloma (RRMM) is highly challenging, especially for patients with disease refractory to initial therapy, and in particular for disease developing refractoriness to lenalidomide. Indeed, with currently approved treatments, median progression-free survival (PFS) in the lenalidomide-refractory setting is less than 10 months, reflecting the difficulty in treating this patient population. Pomalidomide is a second-generation immunomodulatory drug that has shown activity in lenalidomide-refractory disease in the setting of different combinations.

PATIENTS AND METHODS

A real-world study was conducted by the Spanish Myeloma group in a cohort of patients with RRMM treated with pomalidomide, cyclophosphamide, and dexamethasone (PomCiDex). One hundred patients were treated with a median of 3 prior lines of therapy.

RESULTS

Overall response rate was 39%, with a clinical benefit rate of 93%. Median PFS was 7.6 months; median overall survival (OS) was 12.6 months. Median PFS and OS survival were consistent across the different subgroups analyzed. Prolonged PFS and OS were found in patients with responsive disease.

CONCLUSION

Our results compared favorably with those obtained with different pomalidomide-based combinations in a similar patient population. PomCiDex remains a manageable, cost-effective, and all-oral triplet combination for RRMM patients.

Immunotherapy in multiple myeloma: when, where, and for who?

PURPOSE OF REVIEW

Immunotherapy is transforming treatment of multiple myeloma patients in all stages of their disease. This review will discuss recent developments in immunotherapy in multiple myeloma with a focus on antibodies, antibody-drug conjugates, and T-cell-redirection strategies.

RECENT FINDINGS

CD38-targeting antibodies have single agent activity in multiple myeloma, and especially when combined with other drugs, are improving the clinical outcome of patients with newly diagnosed or relapsed/refractory multiple myeloma. Also the SLAMF7-targeting antibody, elotuzumab, improves the survival of relapsed/refractory multiple myeloma patients, when it is combined with either lenalidomide or pomalidomide. Several novel immunotherapies, such as chimeric antigen receptor T cells, antibody-drug conjugates, and bispecific antibodies, are active in patients who developed resistance to all currently available antimultiple myeloma drugs, including immunomodulatory drugs, proteasome inhibitors, and CD38 antibodies. These new immunotherapeutic agents frequently target B-cell maturation antigen, which is highly and uniformly expressed on multiple myeloma cells. However, other targets, such as GPRC5D, are also being investigated.

SUMMARY

Immunotherapy is incorporated into first-line and relapse regimens, and is improving the survival of both newly diagnosed and relapsed/refractory multiple myeloma patients.

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

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

The impact of lenalidomide maintenance on second-line chemotherapy in transplant eligible patients with multiple myeloma

OBJECTIVES

To understand the impact of therapy sequencing on progression-free (PFS) and overall survival (OS) for the treatment of multiple myeloma (MM). The use of daily, low-dose, lenalidomide maintenance (LM) has raised concern for fostering resistance, preventing its use in the relapsed setting.

METHODS

We conducted a retrospective analysis of survival outcomes from the Canadian Myeloma Research Group Database. Patients were grouped based on receipt of LM after autologous stem cell transplant and receipt of lenalidomide in second-line therapy, 575 patients were included.

RESULTS

Patients treated with LM had statistically similar 2nd PFS when re-exposed to lenalidomide in second-line therapy compared to those receiving non-lenalidomide-containing regimens (10.2 vs 14.0 months, P =.53). This cohort also had the longest 2nd OS, 18 months longer than patients treated with LM who did not receive lenalidomide at relapse (55.3 vs 37 months, P =.004). Patients treated with LM also demonstrated deeper responses to second-line therapy than their non-LM counterparts.

CONCLUSION

Our data suggest that patients progressing on LM who receive lenalidomide-containing therapy at first relapse have comparable 2nd PFS and better 2nd OS compared to non-lenalidomide-containing second-line regimens. Identification of patients mostly likely to benefit from further lenalidomide-containing therapy is paramount.

Multiple myeloma

Multiple myeloma is the second most common haematological malignancy in high-income countries, and typically starts as asymptomatic precursor conditions-either monoclonal gammopathy of undetermined significance or smouldering multiple myeloma-in which initiating genetic abnormalities, such as hyperdiploidy and translocations involving the immunoglobulin heavy chain, are already present. The introduction of immunomodulatory drugs, proteasome inhibitors, and CD38-targeting antibodies has extended survival, but ultimately the majority of patients will die from their disease, and some from treatment-related complications. Disease progression and subsequent relapses are characterised by subclonal evolution and increasingly resistant disease. Patients with multiple myeloma usually have hypercalcaemia, renal failure, anaemia, or osteolytic bone lesions-and a detailed diagnostic investigation is needed to differentiate between symptomatic multiple myeloma that requires treatment, and precursor states. Risk stratification using both patient-specific (eg, performance status) and disease-specific (eg, presence of high-risk cytogenetic abnormalities) is important for prognosis and to define the best treatment strategy. Current research strategies include the use of minimal residual disease assays to guide therapy, refining immunotherapeutic approaches, and intercepting disease early in smouldering multiple myeloma.

Cyclophosphamide alters the tumor cell secretome to potentiate the anti-myeloma activity of daratumumab through augmentation of macrophage-mediated antibody dependent cellular phagocytosis

Multiple Myeloma (MM) is a malignant disorder of plasma cells which, despite significant advances in treatment, remains incurable. Daratumumab, the first CD38 directed monoclonal antibody, has shown promising activity alone and in combination with other agents for MM treatment. Daratumumab is thought to have pleiotropic mechanisms of activity including natural killer (NK) cell-mediated antibody-dependent cellular cytotoxicity (ADCC). With the knowledge that CD38-expressing NK cells are depleted by daratumumab, we sought to investigate a potential mechanism of enhancing macrophage-mediated antibody-dependent cellular phagocytosis (ADCP) by combining daratumumab with cyclophosphamide (CTX). Cyclophosphamide’s immunomodulatory function was investigated by conditioning macrophages with tumor cell secretome collected from cyclophosphamide treated MM cell lines (CTX-TCS). Flow cytometry analysis revealed that CTX-TCS conditioning augmented the migratory capacity of macrophages and increased CD32 and CD64 Fcγ receptor expression on their cell surface. Daratumumab-specific tumor clearance was increased by conditioning macrophages with CTX-TCS in a dose-dependent manner. This effect was impeded by pre-incubating macrophages with Cytochalasin D (CytoD), an inhibitor of actin polymerization, indicating macrophage-mediated ADCP as the mechanism of clearance. CD64 expression on macrophages directly correlated with MM cell clearance and was essential to the observed synergy between cyclophosphamide and daratumumab, as tumor clearance was attenuated in the presence of a FcγRI/CD64 blocking agent.

Cyclophosphamide independently enhances daratumumab-mediated killing of MM cells by altering the tumor microenvironment to promote macrophage recruitment, polarization to a pro-inflammatory phenotype, and directing ADCP. These findings support the addition of cyclophosphamide to existing or novel monoclonal antibody-containing MM regimens.

Immunotherapeutic and Targeted Approaches in Multiple Myeloma

The multiple myeloma (MM) therapeutic landscape has evolved significantly with the approval of numerous novel agents, including next generation proteasome inhibitors (PIs), immunomodulatory agents (IMIDs), and monoclonal antibodies (MoABs) targeting CD38 and SLAMF7. While these discoveries have led to an unprecedented improval in patient outcomes, the disease still remains incurable. Immunotherapeutic approaches have shown substantial promise in recent studies of chimeric antigen receptor T-cell (CAR T-cell) therapy, bispecific antibodies, and antibody drug conjugates targeting B-cell maturation antigen (BCMA). This review will highlight these novel and targeted therapies in MM, with particular focus on PIs, IMIDs, MoAb and BCMA-directed immunotherapy.

CyBorD-DARA is potent initial induction for MM and enhances ADCP: initial results of the 16-BCNI-001/CTRIAL-IE 16-02 study

Daratumumab (DARA) has shown impressive activity in combination with other agents for the treatment of multiple myeloma (MM). We conducted a phase 1b study to assess the safety and preliminary efficacy, as well as potential mechanisms of action, of DARA (16 mg/kg) in combination with a weekly schedule of subcutaneous bortezomib (1.3-1.5 mg/m²), cyclophosphamide (150-300 mg/m²), and dexamethasone (40 mg) (CyBorD DARA) as initial induction before autologous stem cell transplantation (ASCT). Eligible patients were ≤70 years of age with untreated MM requiring treatment and who lacked significant comorbidities. A total of 18 patients were enrolled. Their median age was 56 years (range, 32-66 years), and all patients had Eastern Cooperative Oncology Group performance status ≤1. The International Staging System stages were I, II, and III in 78%, 17%, and 6% of patients, respectively; 28% of patients had high-risk genetic features. There was no dose-limiting toxicity, and the incidence of grade 3 or 4 infection or neutropenia was <10%. On an intention-to-treat basis, 94% achieved ≥very good partial response with ≥complete response in 44% of patients. Among 14 of 15 patients who underwent ASCT and were evaluable for response, all 14 achieved at least very good partial response, with 8 (57%) of 14 achieving complete response. After ASCT, 10 (83%) of 12 patients in whom minimal residual disease analysis was possible were negative at a sensitivity of 10^-5 (56% on intention-to-treat/whole study population) according to next-generation sequencing. Flow cytometry analysis of patient samples indicated CyBorD DARA induced activation of macrophage-mediated antibody-dependent cellular phagocytosis. This trial was registered at www.clinicaltrials.gov as #NCT02955810.

Anti-VEGF Drugs in the Treatment of Multiple Myeloma Patients

The interaction between the bone marrow microenvironment and plasma cells plays an essential role in multiple myeloma progression and drug resistance. The vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR) pathway in vascular endothelial cells activates and promotes angiogenesis. Moreover, VEGF activates and promotes vasculogenesis and vasculogenic mimicry when it interacts with VEGF receptors expressed in precursor cells and inflammatory cells, respectively. In myeloma bone marrow, VEGF and VEGF receptor expression are upregulated and hyperactive in the stromal and tumor cells. It has been demonstrated that several antiangiogenic agents can effectively target VEGF-related pathways in the preclinical phase. However, they are not successful in treating multiple myeloma, probably due to the vicarious action of other cytokines and signaling pathways. Thus, the simultaneous blocking of multiple cytokine pathways, including the VEGF/VEGFR pathway, may represent a valid strategy to treat multiple myeloma. This review aims to summarize recent advances in understanding the role of the VEGF/VEGFR pathway in multiple myeloma, and mainly focuses on the transcription pathway and on strategies that target this pathway.

The clinical management of lenalidomide-based therapy in patients with newly diagnosed multiple myeloma

Lenalidomide is an integral, yet evolving, part of current treatment pathways for both transplant-eligible and transplant-ineligible patients with newly diagnosed multiple myeloma (NDMM). It is approved in combination with dexamethasone as first-line therapy for transplant-ineligible patients with NDMM, and as maintenance treatment following autologous stem cell transplantation (ASCT). Although strong clinical trial evidence has supported the integration of lenalidomide into current treatment paradigms for NDMM, applying those paradigms to individual patients and determining which patients are most likely to benefit from lenalidomide treatment are more complex. In this paper, we utilize the available clinical trial evidence to provide recommendations for patient selection and lenalidomide dosing in both the first-line setting in patients ineligible for ASCT and the maintenance setting in patients who have undergone ASCT. In addition, we provide guidance on management of those adverse events that are most commonly associated with lenalidomide treatment, and consider the optimal selection and sequencing of next-line agents following long-term frontline or maintenance treatment with lenalidomide.

Beyond DNA Damage: Exploring the Immunomodulatory Effects of Cyclophosphamide in Multiple Myeloma

The alkylating agent cyclophosphamide has been used in the treatment of multiple myeloma for over 60 years. At low doses, cyclophosphamide also has significant immunomodulatory activity, which can be used to modify the immunosuppressive tumor microenvironment in order to augment responses to existing therapies. Immune-mediated therapies are becoming more widespread in modern approaches to myeloma treatment. In this review, we discuss the effects cyclophosphamide has on the immune system, and how it can be used synergistically with other treatment modalities including the immunomodulatory agents, monoclonal antibodies and cellular therapies.

Venous thromboembolism risk with contemporary lenalidomide-based regimens despite thromboprophylaxis in multiple myeloma: A systematic review and meta-analysis

BACKGROUND

Thromboprophylaxis is routinely used with lenalidomide-based regimens in multiple myeloma because of a substantial risk of venous thromboembolism (VTE). However, little is known about the incidence of VTE with contemporary lenalidomide-based regimens. The objective of the current study was to estimate the incidence of VTE despite thromboprophylaxis with currently used lenalidomide-based regimens in patients with myeloma.

METHODS

The Ovid MEDLINE, Embase, and Cochrane databases were queried from study inception to January 2019 for keywords to cover the following concepts: "lenalidomide," "venous thromboembolism," and "multiple myeloma." Phase 1, 2, and 3 clinical trials evaluating lenalidomide-based regimens with thromboprophylaxis were included. The pooled incidence rate of VTE was estimated using a random-effects model.

RESULTS

The search generated 1372 citations, with 51 clinical trials and 9069 patients included for analysis. The most common thromboprophylaxis agents were aspirin, low-molecular-weight heparin or warfarin, administered either per risk-stratification or at investigators' discretion. The pooled incidence of VTE in trials of patients who had newly diagnosed and relapsed/refractory myeloma was 6.2% (95% CI, 5.4%-7.1%) over median treatment durations ranging from 2 to 34 cycles, which translated into 1.2 VTE events per 100 patient-cycles (95% CI, 0.9-1.7 VTE events per 100 patient-cycles). Among contemporary regimens, the risk of VTE was low with combined lenalidomide and low-dose dexamethasone (0.2 [95% CI, 0.1-0.6] events/100 patient-cycles) and lenalidomide maintenance (0.0 [95% CI, 0.0-0.7] events per 100 patient-cycles). VTE risk was higher with combined lenalidomide and low-dose dexamethasone plus proteasome inhibitors (1.3 [95% CI, 0.7-2.3] events per 100 patient-cycles).

CONCLUSIONS

Despite adequate thromboprophylaxis, lenalidomide-based regimens have a substantial risk of VTE in controlled clinical trial settings. Further studies are needed on new thromboprophylaxis strategies with regimens that have a high VTE risk.

Limited treatment options in refractory multiple myeloma: promising therapeutic developments

Introduction: Combinations of proteasome inhibitors, immunomodulators, and monoclonal antibodies are highly active against multiple myeloma. Consequently, several combinations have moved from the relapsed to the front-line setting. In the context of lenalidomide and bortezomib being used upfront, salvage options need to be evaluated.Areas covered: This manuscript reviews available data for the treatment of patients progressing on optimal frontline strategies, with a focus on the role of second-generation proteasome inhibitors and immunomodulators, monoclonal antibodies and immunotherapy.Expert opinion: Remarkable progress has been made in myeloma treatment due to the integration of immunomodulators, proteasome inhibitors and more recently monoclonal antibodies in the front-line setting. However, we work on the assumption that most individuals will eventually relapse. Optimized upfront therapy negatively selects more resistant patients among still relapsing individuals. Bortezomib and lenalidomide-exposed patients are under-represented in trials leading to currently approved combinations. Evidence needs to be reviewed taking into account how the improvement of frontline therapy has modified the characteristics of patients at the time of relapse. Second generation immunomodulatory agents and proteasome inhibitors, monoclonal antibodies and other agents have shown efficacy in this new landscape. Immunotherapeutic agents, including CAR-T cells are promising for patients failing standard combinations, despite current data are still immature.

How I treat a refractory myeloma patient who is not eligible for a clinical trial

Myeloma patients not eligible for clinical trials have many treatment options. Choosing the next best therapy starts with careful assessment of the biology and dynamics of the disease at relapse, as well as the condition and situation of the patient. Fit patients should be considered for triplet regimens, whereas intermediate and frail patients warrant dose-reduced triplets or doublets. An indolent serologic relapse may be treated with dose intensification, especially in a maintenance situation, whereas a rapid relapse requires a more aggressive approach with drug class change or a second-generation immunomodulatory drug (IMID) or proteasome inhibitor (PI). Monoclonal antibodies, in combination with PIs and IMIDs, have proven highly efficacious in early and late relapse. Key elements of supportive care include infection prevention, bone health, thromboprophylaxis, and management of active symptoms, such as pain and distress.

Nelfinavir and lenalidomide/dexamethasone in patients with lenalidomide-refractory multiple myeloma. A phase I/II Trial (SAKK 39/10)

The antiretroviral agent nelfinavir has antimyeloma activity and can overcome resistance to bortezomib. Our phase I/II trial investigated whether adding nelfinavir to lenalidomide-dexamethasone can overcome lenalidomide resistance in lenalidomide-refractory multiple myeloma (MM). Twenty-nine patients were included (high-risk cytogenetic aberrations 31%; ≥2 prior therapy lines 93%; lenalidomide-bortezomib double-refractory 34%). Twenty-four patients (83%) had prior bortezomib and 10 (34%) were lenalidomide-bortezomib double-refractory. They received four cycles of nelfinavir 2500 mg/day with standard-dose lenalidomide (25 mg days 1-21) and dexamethasone (40/20 mg days 1, 8, 15, 22). Minor response or better was achieved in 16 patients (55%; 95% CI 36-74%), including 40% of those who were lenalidomide-bortezomib double-refractory, and partial response or better in nine patients (31%; 95% CI 15-51%). Median progression-free survival was 3.4 (95% CI 2.0-4.9) months and median overall survival 21.6 (13.0-50.1) months. Lenalidomide-related pneumonitis, pneumonia, and neutropenic fever occurred, but there were no unexpected adverse events. Peripheral blood mononuclear cells showed a 45% (95% CI 40-51%) reduction in total proteasome activity from baseline and significant induction of unfolded protein response and autophagy. Thus, nelfinavir-lenalidomide-dexamethasone is an active oral combination in lenalidomide-refractory MM.

Metronomic Chemotherapy: A Systematic Review of the Literature and Clinical Experience

Metronomic chemotherapy, continuous and dose-dense administration of chemotherapeutic drugs with lowered doses, is being evaluated for substituting, augmenting, or appending conventional maximum tolerated dose regimens, with preclinical and clinical studies for the past few decades. To date, the principle mechanisms of its action include impeding tumoral angiogenesis and modulation of hosts' immune system, affecting directly tumor cells, their progenitors, and neighboring stromal cells. Its better toxicity profile, lower cost, and easier use are main advantages over conventional therapies. The evidence of metronomic chemotherapy for personalized medicine is growing, starting with unfit elderly patients and also for palliative treatment. The literature reviewed in this article mainly demonstrates that metronomic chemotherapy is advantageous for selected patients and for certain types of malignancies, which make it a promising therapeutic approach for filling in the gaps. More clinical studies are needed to establish a solidified role for metronomic chemotherapy with other treatment models in modern cancer management.

Treatment of patients with multiple myeloma progressing on frontline-therapy with lenalidomide

Over the last years, there has been great progress in the treatment of multiple myeloma with many new agents and combinations having been approved and being now routinely incorporated into treatment strategies. As a result, patients are experiencing benefits in terms of survival and better tolerance. However, the multitude of treatment options also presents a challenge to select the best options tailored to the specific patient situation. Lenalidomide is increasingly being used as part of frontline therapy in newly diagnosed multiple myeloma. This agent is typically administered until disease progression. It is currently unclear, how to best manage patients, who relapse while receiving lenalidomide as part of their frontline treatment. We conducted a review to summarize the available evidence in this setting. Our summary shows that there are very few data from current trials testing new combinations based on carfilzomib, pomalidomide, or daratumumab that address this specific patient population. Our review is aimed to summarize the available evidence to assist treatment decision making and to raise awareness of this lack of data to encourage further analyses and the incorporation of sequencing questions in future trial designs.

Addition of Cyclophosphamide "On Demand" to Lenalidomide and Corticosteroids in Patients With Relapsed/Refractory Multiple Myeloma-A Retrospective Review of a Single-center Experience

INTRODUCTION

The combination of lenalidomide and dexamethasone (Len-Dex) is an established regimen for patients with relapsed or refractory myeloma. To prolong the benefit of this effective regimen, the Myeloma Program at Princess Margaret Cancer Centre has routinely added a third agent, oral cyclophosphamide (Cy) given weekly, to Len-Dex at disease progression.

PATIENTS AND METHODS

In the present report, we describe the cases of 53 patients who had received Len-Dex-Cy for a minimum of 4 weeks from January 2007 to December 2014 after progression with Len-Dex alone. The dose of added Cy ranged from 250 to 500 mg weekly. The median number of previous regimens, including Len-Dex, was 2 (range, 2-4); 80% of patients had undergone previous autologous stem cell transplantation.

RESULTS

The overall rate of response equal to or greater than a partial response was 34%, and clinical benefit (stable disease or better) was observed in 87% of the patients. The median duration of Len-Dex-Cy therapy was 6.9 months (range, 0.9-55.1 months). The median progression-free survival was 6.1 months (range, 4.2-8.1 months) from the addition of Cy and 24.1 months (range, 15.9-32.0 months) from start of Len-Dex.

CONCLUSION

The addition of Cy for patients with myeloma developing progression with Len-Dex was an inexpensive option with manageable toxicity that resulted in a clinically meaningful extension of disease control.

Pomalidomide, cyclophosphamide, and dexamethasone for relapsed multiple myeloma

It is important to have an effective therapy for patients with multiple myeloma (MM) at first relapse, particularly if an autologous stem cell transplant (ASCT) is considered at this stage. This multicenter, phase 2 trial evaluated the efficacy and safety of weekly oral pomalidomide-cyclophosphamide-dexamethasone (PCD) in patients with MM in first relapse after treatment with lenalidomide-bortezomib-dexamethasone (RVD). All patients had received RVD as induction and consolidation therapy, plus lenalidomide maintenance for 1 year (arm A). Half had also received an ASCT after induction (arm B). At MM relapse, all patients received 4 oral cycles of pomalidomide 4 mg (days 1-21), cyclophosphamide 300 mg (days 1, 8, 15, and 22), and dexamethasone 40 mg (days 1-4 and days 15-18 of a 28-day cycle; PCD). Responding patients in arm A underwent ASCT and received 2 additional cycles of PCD, whereas those in arm B received 5 cycles of PCD. All patients received pomalidomide-dexamethasone maintenance until disease progression. Primary end point was partial remission or better after the initial 4 cycles of PCD. Responses were obtained in 82/97 (85%) patients evaluated: complete remission (n = 1; 1%), very good partial remission (n = 32; 33%), and partial remission (n = 49; 51%). Three patients (3%) had stable disease, and 6 (6%) had disease progression (6 response failures). Forty-five (94%) of the 48 patients in arm A underwent planned ASCT. PCD was effective therapy after first relapse with RVD. After 4 cycles, the rate of partial remission or better was 85%, and 94% of planned ASCTs were performed. Toxicity was mostly hematologic and manageable. This trial was registered at www.clinicaltrials.gov as #NCT02244125.

Lenalidomide combined with low-dose cyclophosphamide and prednisone modulates Ikaros and Aiolos in lymphocytes, resulting in immunostimulatory effects in lenalidomide-refractory multiple myeloma patients

We recently showed that the outcome of multiple myeloma (MM) patients treated in the REPEAT study (evaluation of lenalidomide combined with low-dose cyclophosphamide and prednisone (REP) in lenalidomide-refractory MM) was markedly better than what has been described with cyclophosphamide-prednisone alone. The outcome with REP was not associated with plasma cell Cereblon expression levels, suggesting that the effect of REP treatment may involve mechanisms independent of plasma cell Cereblon-mediated direct anti-tumor activity. We therefore hypothesized that immunomodulatory effects contribute to the anti-MM activity of REP treatment, rather than plasma cell Cereblon-mediated effects. Consequently, we now characterized the effect of REP treatment on immune cell subsets in peripheral blood samples collected on day 1 and 14 of cycle 1, as well as on day 1 of cycle 2. We observed a significant mid-cycle decrease in the Cereblon substrate proteins Ikaros and Aiolos in diverse lymphocyte subsets, which was paralleled by an increase in T-cell activation. These effects were restored to baseline at day one of the second cycle, one week after lenalidomide interruption. In vitro, lenalidomide enhanced peripheral blood mononuclear cell-mediated killing of both lenalidomide-sensitive and lenalidomide-resistant MM cells in a co-culture system. These results indicate that the Cereblon-mediated immunomodulatory properties of lenalidomide are maintained in lenalidomide-refractory MM patients and may contribute to immune-mediated killing of MM cells. Therefore, combining lenalidomide with other drugs can have potent effects through immunomodulation, even in patients considered to be lenalidomide-refractory.

Update on the role of lenalidomide in patients with multiple myeloma

Lenalidomide is a derivative of thalidomide and belongs to the class of drugs known as the immunomodulatory drugs (IMiDs). The IMiDs have played a large role in improving the survival outcomes of patients with multiple myeloma. In particular, lenalidomide is currently standard of care in the newly diagnosed setting, in the maintenance setting post-autologous stem cell transplant, as well as in the relapsed/refractory setting. While the combination of lenalidomide and various proteasome inhibitors has proven particularly effective, there are emerging data demonstrating the effectiveness of lenalidomide in combination with other important classes of drugs including the monoclonal antibodies. Recent studies have provided insight into the molecular target of lenalidomide and the other IMiDs, although there is still much to be learned regarding the mechanisms by which lenalidomide affects the myeloma cell and the immune system. Here we review the molecular mechanisms of action, side effects, and the results of the clinical trials which have led to the widespread incorporation of lenalidomide into the myeloma therapeutic armamentarium.

Cyclophosphamide's addition in relapsed/refractory multiple myeloma patients with biochemical progression during lenalidomide-dexamethasone treatment

OBJECTIVE

The aim of this study was to evaluate the addition of cyclophosphamide in relapsed-refractory multiple myeloma patients (RRMM) who experienced biochemical relapse or progression without CRAB, during treatment with lenalidomide and dexamethasone (Rd), to slow down the progression in active relapse.

METHODS

This analysis included 31 patients with RRMM treated with Rd who received cyclophosphamide (CRd) at biochemical relapse. The CRd regimen was continued until disease progression.

RESULTS

The median number of CRd cycles administered was 8 (range: 1-35). A response was observed in 9 (29%) patients. After a median observation time of 11 months, the median overall survival (OS) from the beginning of CRd was 17.7 months. The median progression-free survival (PFS) from the beginning of CRd was 13.1 months.

CONCLUSION

The addition of cyclophosphamide delays the progression in patients who present a biochemical relapse during Rd treatment. The response rate and the duration of PFS obtained with minimal toxicities and low costs induced us to setting up a randomized clinical trial.

Current and New Therapeutic Strategies for Relapsed and Refractory Multiple Myeloma: An Update

Although survival of multiple myeloma patients has at least doubled during recent years, most patients eventually relapse, and treatment at this stage may be particularly complex. At the time of relapse, the use of alternative drugs to those given upfront is current practice. However, many new options are currently available for the treatment of relapsed multiple myeloma, including recently approved drugs, such as the second- and third-generation proteasome inhibitors carfilzomib and ixazomib, the immunomodulatory agent pomalidomide, the monoclonal antibodies daratumumab and elotuzumab and the histone deacetylase inhibitor panobinostat, but also new targeted agents are under active investigation (e.g. signal transduction modulators, kinesin spindle protein inhibitors, and inhibitors of NF-kB, MAPK, AKT). We here describe a new paradigm for the treatment of relapsed multiple myeloma. The final goal should be finding a balance among efficacy, toxicity, and cost and, at the end of the road, achieving long-lasting control of the disease and eventually even cure in a subset of patients.

Apoptosis in human liver carcinoma caused by gold nanoparticles in combination with carvedilol is mediated via modulation of MAPK/Akt/mTOR pathway and EGFR/FAAD proteins

In cancers, apoptosis signaling pathways and cell survival and growth pathways responsible for resistance to conventional treatments, such as Pi3K/Akt/mTOR and mitogen-activated protein kinase (MAPK) become dysregulated. Recently, alternative treatments to promote tumor cell death have become important. The present study reports on the antitumor and cytoprotective action of gold nanoparticles (GNPs) and carvedilol in combination and in isolated application. Apoptosis was analyzed by FITC/propidium iodide staining flow cytometry; caspase-3, caspase-8, Bcl-2 and MAPK/ERK activity by immunofluorescence microscopy; gene expression of proteins related to cell death as Akt, mTOR, EGFR, MDR1, survivin, FADD and Apaf, by the real-time PCR; and western blot analysis for MAPK/ERK, Akt and mTOR. Oxidative stress evaluation was performed by reduced glutathione (GSH) and malondialdehyde (MDA) levels. Intracellular GNPs targets were identified by transmission electron microscopy. After exposure to a combination of GNPs (6.25 µg/ml) and carvedilol (3 µM), death as promoted by apoptosis was detected using flow cytometry, for expression of pro-apoptotic proteins FADD, caspase-3, caspase-8 and sub-regulation of anti-apoptotic MAPK/ERK, Akt, mTOR, EGFR and MDR1 resistance. Non-tumor cell cytoprotection with GSH elevation and MDA reduction levels was detected. GNPs were identified within the cell near to the nucleus when combined with carvedilol. The combination of GNP and carvedilol promoted downregulation of anti-apoptotic and drug resistance genes, over-regulation of pro-apoptotic proteins in tumor cells, as well as cytoprotection of non-tumor cells with reduction of apoptosis and oxidative stress.

Current and developing synthetic pharmacotherapy for treating relapsed/refractory multiple myeloma

INTRODUCTION

The introduction of novel agents has significantly improved multiple myeloma (MM) patient outcome during the last two decades. MM received the most drug approvals for any one malignancy during this time period, both in the United States as well as in Europe. Areas covered: Proteasome inhibitors, immunomodulatory drugs, and monoclonal antibodies are prototype drug classes, which target both specific MM cell functions, as well as the tumor supportive bone marrow microenvironment, and represent current cornerstones of MM therapy. Importantly, the unprecedented extent and frequency of durable responses, in relapsed/refractory multiple myeloma (RRMM), in particular, is predominantly based on the combinatorial use of these agents with conventional chemotherapeutics or representatives of other drug classes. This article will summarize past landmark discoveries in MM that led to the dramatic progress of today's clinical practice. Moreover, developing strategies will be discussed that are likely to yet improve patient outcome even further. Expert opinion: Despite significant therapeutic advancements, MM remains an incurable disease. With several novel agents in the preclinical and early clinical pipeline, among those novel CD38 and BCMA mAbs, immune checkpoint inhibitors, as well as ricolinostat, selinexor, venetoclax, CAR-T cells, and vaccines, further advances in MM patient outcome are expected in the near future.

Immunomodulatory Drugs in Multiple Myeloma: Mechanisms of Action and Clinical Experience

Over the last two decades, the outcomes for patients with multiple myeloma, a plasma cell malignancy, have dramatically improved. The development of the immunomodulatory drugs (IMiDs), which include thalidomide, lenalidomide, and pomalidomide, has contributed significantly to these improved outcomes. While thalidomide is now less commonly prescribed, lenalidomide is widely used in the treatment of newly diagnosed transplant-eligible and transplant-ineligible patients, in the maintenance setting post-transplant and in the relapsed/refractory setting, while pomalidomide is currently utilized in the relapsed/refractory setting. The IMiDs have been reported to have a multitude of activities, including anti-angiogenic, cytotoxic, and immunomodulatory. However, the more recent discoveries that the IMiDs bind to cereblon and thus regulate the ubiquitination of key transcription factors including IKZF1 and IKZF3 have provided greater insight into their mechanism of action. Here, the clinical efficacy of these agents in myeloma is reviewed and the structure-function relationship, the molecular mechanisms of action, and the association of IMiDs with second primary malignancies and thrombosis are discussed.