Combined thalidomide and cyclophosphamide treatment for refractory or relapsed multiple myeloma patients: a prospective phase II study

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.

Immunomodulatory drugs and the risk of serious infection in multiple myeloma: systematic review and meta-analysis of randomized and observational studies

The effect of immunomodulatory drugs (IMiDs) on serious infection remains uncertain. We therefore conducted a systematic review and meta-analysis to assess the possible impact of IMiDs on serious infection in patients with multiple myeloma (MM). We searched randomized controlled trials (RCTs) and observational studies from databases that addressed the effect of IMiDs on serious infection in patients with MM. We pooled data from RCTs and observational studies separately and used the GRADE approach to rate the quality of evidence. Rates in patients with individual IMiDs at different treatment status ranged from 7.00 to 23.00%. The use of thalidomide- or lenalidomide-based regimen induction therapy for autologous stem cell transplantation (ASCT)-ineligible patients suggests increase in serious infection (RR = 1.59, 95% CI 1.31-1.93, p < 0.01). Compared to conventional therapy, IMiDs' induction in ASCT-eligible patients significantly decreases the risk of serious infection (RR = 0.82, 95% CI 0.72-0.94, p < 0.01). Lenalidomide-based therapy was associated with a significant increase in risk of serious infection in patients treated compared with conventional therapy (RR = 2.45, 95% CI 1.57-3.83, p < 0.01). The current evidence suggests that patients with MM treated with IMiDs are at a high risk of serious infection.

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.

18F-FDG PET increases visibility of bone lesions in relapsed multiple myeloma: is this hypoxia-driven?

INTRODUCTION

Whole-body x-ray (WBX) is used for detecting skeleton abnormalities in patients with multiple myeloma (MM). An alternative might be 18F-FDG PET, which makes use of metabolic changes of malignant cells. The aims of this study were to evaluate whether 18F-FDG PET detects more lesions compared with WBX in patients with relapsing MM and to define its prognostic value. In addition 1-α-D-(5-deoxy-5-[F]-fluoroarabinofuranosyl)-2-nitroimidazole (18F-FAZA) scan and immunohistochemical staining on bone marrow were performed to define whether FDG uptake coincides with angiogenesis-related tumor hypoxia.

PATIENTS AND METHODS

18F-FDG PET (n = 44) and 18F-FAZA-PET (n = 5) were performed in patients with relapsed MM. Bone marrow biopsies (n = 20) were evaluated for hypoxia inducible factors (HIF) 1α and 2α, vascular endothelial growth factor, glucose transport proteins 1 and 3, and the microvessel density.

RESULTS

New lesions were more frequently demonstrated on 18F-FDG PET than on WBX (P = 0.000001). 18F-FDG PET was not predictive for progression-free survival and overall survival. Immunohistochemical staining on bone marrow biopsies demonstrated a significant increase in microvessel density and elevated expression of vascular endothelial growth factor, HIF-2α, and glucose transport protein 3 by the malignant plasma cells. However, HIF-1α expression and 18F-FAZA scan results were negative.

CONCLUSIONS

Our results demonstrate that 18F-FDG PET is relevant for diagnostic purposes compared with WBX in relapsing MM. The enhanced uptake of 18F-FDG PET is likely related to the activation of the HIF-2α signaling pathway but probably independent of hypoxia-induced signaling in view of the negative findings on both 18F-FAZA-PET and HIF-1α expression.

Venous and arterial thrombotic risks with thalidomide: evidence and practical guidance

Oral immunomodulatory drugs (IMiDs), namely thalidomide, lenalidomide and pomalidomide, interfere with several pathways important for disease progression. Today they play a crucial role in the treatment of multiple myeloma patients, and have considerably improved myeloma outcomes. These agents, and thalidomide in particular, are associated with higher rates of thromboembolic events, both venous and arterial. Individual risk factors for thromboembolic events include advanced age, previous history of thromboembolism, an indwelling central venous catheter, comorbid conditions (e.g. infections, diabetes, cardiac disease, obesity), current or recent immobilization, recent surgery and inherited thrombophilic abnormalities. Cancer therapy and cancer itself also increase the risk of thromboembolic events. The aim of this review is to help clinicians to define the risk of thrombotic events in patients treated with thalidomide and thus to provide practical recommendations to manage thromboprophylaxis in these patients.

Choosing treatment options for patients with relapsed/refractory multiple myeloma

Multiple myeloma (MM) is a clonal plasma cell disorder that is still incurable using conventional treatments. Over the last decade, advances in front-line therapy have led to an increase in survival, but there are still some doubts in the case of relapsed/refractory disease. We searched the PubMed database for articles on treatment options for patients with relapsed/refractory MM published between 1996 and 2013. These treatments included hematopoietic cell transplantation (HCT), rechallenges using previous chemotherapy regimens, and trials of new regimens. The introduction of new agents such as the immunomodulatory drugs (IMIDs) thalidomide and lenalidomide, and the first-in-its-class proteasome inhibitor bortezomib, has greatly improved clinical outcomes in patients with relapsed/refractory MM, but not all patients respond and those that do may eventually relapse or become refractory to treatment. The challenge is therefore to select the optimal treatment for each patient by balancing efficacy and toxicity. To do this, it is necessary to consider disease-related factors, such as the quality and duration of responses to previous therapies, and the aggressiveness of the relapse, and patient-related factors such as age, comorbidities, performance status, pre-existing toxicities and cytogenetic patterns. The message from the trials reviewed in this article is that the new agents may be used to re-treat relapsed/refractory disease, and that the sequencing of their administration should be modulated on the basis of the various disease and patient-related factors. Moreover, our understanding of the pharmacology and molecular action of the new drugs will contribute to the possibility of developing tailored treatment.

Novel immunomodulatory compounds in multiple myeloma

INTRODUCTION

The treatment options for patients with multiple myeloma (MM) remain limited. Immunomodulatory agents (IMiDs), such as thalidomide and lenalidomide, have changed the landscape in the treatment of patients with MM while newer IMiDs such as pomalidomide are showing promise in early clinical trials.

AREAS COVERED

This review focuses on the biologic rationales of IMiDs and the clinical results supporting their use in MM. It includes data on the new IMiD, pomalidomide and also explores the possible utility of combining IMiDs with other agents. A PubMed search and abstracts from oncology scientific meetings (ASCO and ASH) of articles related to IMiDs and MM was conducted.

EXPERT OPINION

IMiDs have shown clinical activity as single agents and in combination. Thalidomide was the first in class drug. Lenalidomide has a better toxicity profile than thalidomide. Pomalidomide may overcome resistance to lenalidomide indicating differences in their mechanisms of action and resistance. Molecular biomarkers may allow us to identify patients who will respond to IMiDs.

Management strategies for relapsed/refractory multiple myeloma: current clinical perspectives

In the last decade, the introduction of novel agents including the immunomodulatory drugs thalidomide and lenalidomide, and the first-in-class proteasome inhibitor bortezomib, has dramatically improved clinical outcome in patients with relapsed/refractory multiple myeloma (MM) compared to conventional chemotherapy alone. Although combination treatment approaches with traditional cytotoxic agents and novel agents have led to response rates as high as 85% in patients with relapsed/refractory disease, not all patients will respond to established novel agents, and even those who do respond will ultimately relapse or become refractory to currently available regimens. There is no generally accepted standard treatment for patients with relapsed/refractory disease; however, both disease-related (eg, quality and duration of response to previous therapies and the aggressiveness of the relapse) and patient-related (eg, preexisting toxicities, comorbid conditions, quality of life, age, and performance status) factors should be considered when selecting the best treatment option. This article will review up-to-date approaches for managing patients with relapsed/refractory MM, including the efficacy and safety of established novel agents, the use of adjunctive/supportive care, and strategies for tailored treatment.

Treatment options for relapsed and refractory multiple myeloma

Treatment options for patients with relapsed myeloma have benefited from the development of new targeted agents. The use of bortezomib, thalidomide, and lenalidomide have dramatically changed outcomes for patients with relapsed myeloma. New agents are also in development, on the basis of preclinical rationale, as well as combinations of conventional and novel agents. Together each of these treatment approaches are being tested in phase I, II, and III clinical trials, with the goal of prolonged duration of remission and, ultimately, improved overall survival.

Rates of venous thromboembolism in multiple myeloma patients undergoing immunomodulatory therapy with thalidomide or lenalidomide: a systematic review and meta-analysis

INTRODUCTION

The incidence of venous thromboembolism (VTE) in patients with multiple myeloma (MM) treated with thalidomide- and lenalidomide-based regimens is high. Recent observational studies have suggested that thromboprophylaxis might be efficacious in decreasing the risk of VTE in this population.

PURPOSE

To determine the absolute rates of VTE with and without different thromboprophylactic agents in patients with newly diagnosed or previously treated MM receiving thalidomide- or lenalidomide-based regimens.

RESULTS

Patients with newly diagnosed MM treated with thalidomide in combination with dexamethasone have a VTE risk of 4.1 (95% CI, 2.8-5.9) per 100 patient-cycles. Therapeutic doses of anticoagulants seem to provide the largest absolute risk reduction of VTE. The rate of VTE in patients with previously treated MM receiving thalidomide in combination with dexamethasone is 0.8 (95% CI, 0.1-2.1) per 100 patient-months. A combination of lenalidomide and dexamethasone is associated with of risk of VTE of 0.8 (95% CI, 0.07-2.0) per 100 patient-cycles and 0.7 (95% CI, 0.4-0.9) per 100 patient-cycles in patients with newly diagnosed and previously treated MM, respectively. Similarly, the rates of VTE in patients also receiving thromboprophylaxis with aspirin were 0.9 (95% CI, 0.5-1.5) and 0.6 (95% CI, 0.01-2.1), respectively.

CONCLUSION

Patients with newly diagnosed or previously treated MM receiving thalidomide- or lenalidomide-based regimens in combination with dexamethasone are at high risk of VTE. The benefit of various types of thromboprophylaxis is difficult to quantify in patients with MM receiving immunomodulatory therapy, especially in those receiving lenalidomide-based therapy or who have previously treated MM. Randomized controlled trials are needed to address this important clinical need.

Treatment of relapsed and refractory multiple myeloma in the era of novel agents

The introduction of the Immunomodulatory drugs (IMiDs) and proteasome inhibitors, used either as a single-agent or combined with classic anti-myeloma therapies, has improved the outcome for patients with relapsed myeloma. However, there is currently no generally accepted standard treatment for relapsed/refractory myeloma patients, partly because of the absence of trials comparing the efficacy of the novel agents in relapsed/refractory myeloma. Choice of a new treatment regimen depends on both patient and disease-specific characteristics. A lenalidomide-based regimen is the first choice in patients with neuropathy, while bortezomib has the highest efficacy in patients with renal insufficiency and is not associated with increased risk of thromboembolism. A second autologous stem cell transplantation (auto-SCT) can be applied in patients with a progression-free period of ≥ 18-24 months after the first auto-SCT. In high-risk relapse such as occurring early after auto-SCT consolidation with allogeneic SCT can be considered. In this review we provide an overview of the various salvage regimens and give recommendations for treatment of patients with relapsed/refractory myeloma in different clinical settings.

Improved survival among younger but not among older patients with Multiple Myeloma in the Netherlands, a population-based study since 1989

This study assesses whether new treatment strategies developed in clinical trials translate into improved survival for multiple myeloma (MM) patients in the Netherlands. All patients diagnosed with MM in the Northern part of the Netherlands between 1989 and 2005 were retrieved from two regional population-based cancer registries. Information on study participation was derived from linkage with trial information systems. The effect of period of diagnosis (1989-1992, 1993-1996, 1997-2000, 2001-2005), age (<50, 50-65, 66-74, 75), gender, Salmon-Durie (SD) stage, trial participation and treatment on relative survival were studied. In total 4985 patients were included. When trial participation was analysed for exact periods in which trials were open, 16% of patients aged 65 years with SD-stage I and 38% with SD-stage II or III were enrolled compared to 2% of patients aged >65 years with SD-stage I and 5% with SD-stage II or III. Relative survival decreased with age (p<.001), with advanced stage (p<.001) and was better for patients enrolled in trials (p<.001). Five-year relative survival increased from 34% (95% confidence interval (95% CI) 28-39%) in 1989-1992 to 56% (95% CI 50-61%) in 2001-2005 for patients 65 years. The excess mortality was 37% lower in 2001-2005 than in 1989-1992 for these patients, adjusted for age, stage, trial participation and gender (p<.001). Survival did not improve for older patients.

IN CONCLUSION

MM survival improved among younger but not among older patients since the mid-1990s. The improved survival of younger patients coincided with increasing trial participation and increasing use of high-dose chemotherapy and autologous stem-cell transplantation.

Somatostatin receptor scintigraphy might be useful for detecting skeleton abnormalities in patients with multiple myeloma and plasmacytoma

Purpose

Somatostatin receptor expression has been demonstrated on a number of plasma cell lines. Therefore, we questioned whether somatostatin receptor scintigraphy (SRS) can be used to demonstrate in vivo multiple myeloma (MM) activity.

Methods

SRS was performed in newly diagnosed (n = 9) or relapsing (n = 18) MM patients or in patients with localized plasmacytoma (n = 2). The results were compared with radiographic findings.

Results

A positive SRS was demonstrated in 44% of the newly diagnosed patients, in 83% of the relapsed patients and in both patients with plasmacytoma. The SRS findings corresponded with radiographic abnormalities in 40% of the patients. However, in relapsed patients 60% demonstrated increased SRS uptake in areas without new radiographic abnormalities. The positive SRS corresponded with histologically proven disease activity and responded upon treatment. Moreover, immunohistochemical staining of MM material demonstrated concordant somatostatin receptor sst3 staining in five of six patients.

Conclusion

These results demonstrate that SRS is a valuable tool to detect disease activity, especially in relapsing MM patients.

Management of multiple myeloma: the changing landscape

Many changes have been incorporated into the approach to multiple myeloma over the last few years, due to improvements in our understanding of the disease biology. New diagnostic and prognostic criteria from the International Myeloma Working Group have clarified the initial clinical approach to this disease. The prognostic impact of chromosomal abnormalities is now recognized, and the detection of specific abnormal cytogenetics is beginning to influence therapeutic decisions. The introduction of the novel agents thalidomide, bortezomib and lenalidomide has expanded treatment options at different points in the disease course; these agents are being evaluated in conjunction with conventional chemotherapy and stem cell transplantation. This report highlights some of the key recent findings in multiple myeloma, and describes areas for future research.

Lenalidomide in multiple myeloma

Current therapies for multiple myeloma include steroids, alkylating agents and high-dose chemotherapy with autologous stem cell transplant. These approaches are typically associated with initially good response rates, but they ultimately fail as a result of disease progression. New therapies that overcome resistance, lower toxicity and maintain remission are needed. Recent advances in the treatment of multiple myeloma include bortezomib and thalidomide. Lenalidomide (Revlimid) is an immunomodulatory drug that has undergone rapid clinical development in multiple myeloma and was recently approved by the US FDA for use in patients with relapsed disease. Clinical trials demonstrate that lenalidomide, particularly in combination with dexamethasone, produces durable clinical responses in patients with relapsed and refractory disease and is generally well tolerated, with manageable toxicities. This review summarizes the profile of lenalidomide and the current evidence for its efficacy in multiple myeloma.

Thrombotic Complications of Myeloma Therapy

Patients with multiple myeloma are at relatively high baseline risk of developing thromboembolic events (TEE), usually deep vein thromboses. There are numerous contributing factors, among them certain treatment regimens that include thalidomide or related compounds such as lenalidomide combined with glucocorticoids and/or cytotoxic chemotherapy. The risk of developing TEE appears to be particularly high when these immunomodulatory agents are combined with anthracyclines as treatment of newly-diagnosed disease. Up-front combinations including thalidomide plus pulse dexamethasone and/or alkylating agents are associated with an intermediate risk, whereas the same regimens for relapsed/refractory myeloma seem to be associated with the lowest risk. Several different thromboprophylaxis strategies have been effective in lowering the risk of developing clots: daily aspirin (81–325 mg/day), full-intensity warfarin (INR 2–3), and prophylactic enoxaparin (40 mg SQ daily). Low, fixed-dose warfarin may also reduce the risk of TEE, but the data on this are disputable. None of these TEE prevention strategies have been prospectively compared head-to-head, so the choice often reflects physician and/or patient preferences. The available evidence upon which one might make such a decision is reviewed here.

An Update of the Management of Multiple Myeloma: The Changing Landscape

The management of multiple myeloma is rapidly changing. Cytogenetic, molecular and proteomic techniques have led to a better understanding of the pathophysiology of this heterogeneous malignancy. Novel agents designed to interrupt myeloma growth and survival pathways have entered into clinical usage with unprecedented speed, while new prognostic systems based on clinical and biologic features, such as cytogenetic abnormalities, have been developed. A plethora of clinical trials have been initiated utilizing novel agents, alone or in conjunction with established modalities such as conventional cytotoxic agents and stem cell transplantation. These newer treatments have increased the antitumor response rates in this disease and have provided options for patients whose disease has become resistant to conventional therapy. A major challenge is to define the optimal use of these new agents and combinations in order to significantly impact the natural history of myeloma.