Multicenter, randomized, double-blind, placebo-controlled study of thalidomide plus dexamethasone compared with dexamethasone as initial therapy for newly diagnosed multiple myeloma

Impact of dexamethasone responsiveness on long term outcome in patients with newly diagnosed multiple myeloma

Dexamethasone (Dex), alone or in combination, is commonly used for treating multiple myeloma. Dex as single agent for initial therapy of myeloma results in overall response rates of 50-60%. It is unclear whether steroid responsiveness reflects any biological characteristic that impacts long-term outcome. We studied a cohort of 182 patients with newly diagnosed myeloma seen between March 1998 and June 2007, initially treated with single-agent Dex for at least 4 weeks. The median age at diagnosis was 63 years (range, 39-81) and the median estimated survival was 55 months. At a median duration of therapy of 15 weeks, 91 (50%) patients had a partial response or better, 80 (44%) had less than partial response and the remaining (6%) patients were not evaluable. The median overall survival from diagnosis for the responders was 75 months compared to 71 months for remaining patients, P = 0.6.There was no correlation between baseline disease characteristics and Dex responsiveness. While overall survival was longer for the 130 (70%) patients who proceeded to an autologous stem cell transplant, no correlation was found between survival and Dex responsiveness among either group. Among this cohort of patients with myeloma, failure to respond to single agent steroid did not have an adverse impact on eventual outcome.

Management of newly diagnosed symptomatic multiple myeloma: updated Mayo Stratification of Myeloma and Risk-Adapted Therapy (mSMART) consensus guidelines

Multiple myeloma is a malignant plasma cell neoplasm that affects more than 20,000 people each year and is the second most common hematologic malignancy. It is part of a spectrum of monoclonal plasma cell disorders, many of which do not require active therapy. During the past decade, considerable progress has been made in our understanding of the disease process and factors that influence outcome, along with development of new drugs that are highly effective in controlling the disease and prolonging survival without compromising quality of life. Identification of well-defined and reproducible prognostic factors and introduction of new therapies with unique modes of action and impact on disease outcome have for the first time opened up the opportunity to develop risk-adapted strategies for managing this disease. Although these risk-adapted strategies have not been prospectively validated, enough evidence can be gathered from existing randomized trials, subgroup analyses, and retrospective studies to develop a working framework. This set of recommendations represents such an effort-the development of a set of consensus guidelines by a group of experts to manage patients with newly diagnosed disease based on an interpretation of the best available evidence.

Phase 2 study of two sequential three-drug combinations containing bortezomib, cyclophosphamide and dexamethasone, followed by bortezomib, thalidomide and dexamethasone as frontline therapy for multiple myeloma

Novel sequential combination therapy for induction may improve the quality of response and therefore prolong survival in newly diagnosed multiple myeloma (MM) patients. We report results from a phase 2 study of two sequential three-drug combinations. Forty-four previously untreated, symptomatic MM patients received: bortezomib 1.3 mg/m(2) (days 1, 4, 8, 11), cyclophosphamide 300 mg/m(2) (days 1, 8), plus dexamethasone 40 mg (day of and day after bortezomib) for three 21-day cycles, followed by bortezomib 1.0 mg/m(2), dexamethasone 40 mg and thalidomide 100 mg daily for three cycles. Overall response rate for 42 evaluable patients was 95%, including 19% stringent complete response (sCR), 26% CR, and 57%>/= very good partial response. Twenty-two patients have undergone stem-cell transplantation. After a median follow-up of 20.9 months, five patients have died; none was induction therapy-related. Median event-free survival (EFS) and overall survival (OS) have not been reached; estimated 1-year EFS and OS rates were 81% and 91% respectively. Both three-drug combinations were well tolerated; 82% of patients completed all six cycles. Toxicities were predictable and manageable; the most-commonly reported grade 3/4 toxicity was neuropathy (11%). This novel sequential three-drug combination therapy is effective and well-tolerated in previously untreated MM patients.

Lenalidomide plus high-dose dexamethasone versus lenalidomide plus low-dose dexamethasone as initial therapy for newly diagnosed multiple myeloma: an open-label randomised controlled trial

BACKGROUND

High-dose dexamethasone is a mainstay of therapy for multiple myeloma. We studied whether low-dose dexamethasone in combination with lenalidomide is non-inferior to and has lower toxicity than high-dose dexamethasone plus lenalidomide.

METHODS

Patients with untreated symptomatic myeloma were randomly assigned in this open-label non-inferiority trial to lenalidomide 25 mg on days 1-21 plus dexamethasone 40 mg on days 1-4, 9-12, and 17-20 of a 28-day cycle (high dose), or lenalidomide given on the same schedule with dexamethasone 40 mg on days 1, 8, 15, and 22 of a 28-day cycle (low dose). After four cycles, patients could discontinue therapy to pursue stem-cell transplantation or continue treatment until disease progression. The primary endpoint was response rate after four cycles assessed with European Group for Blood and Bone Marrow Transplant criteria. The non-inferiority margin was an absolute difference of 15% in response rate. Analysis was by modified intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00098475.

FINDINGS

445 patients were randomly assigned: 223 to high-dose and 222 to low-dose regimens. 169 (79%) of 214 patients receiving high-dose therapy and 142 (68%) of 205 patients on low-dose therapy had complete or partial response within four cycles (odds ratio 1.75, 80% CI 1.30-2.32; p=0.008). However, at the second interim analysis at 1 year, overall survival was 96% (95% CI 94-99) in the low-dose dexamethasone group compared with 87% (82-92) in the high-dose group (p=0.0002). As a result, the trial was stopped and patients on high-dose therapy were crossed over to low-dose therapy. 117 patients (52%) on the high-dose regimen had grade three or worse toxic effects in the first 4 months, compared with 76 (35%) of the 220 on the low-dose regimen for whom toxicity data were available (p=0.0001), 12 of 222 on high dose and one of 220 on low-dose dexamethasone died in the first 4 months (p=0.003). The three most common grade three or higher toxicities were deep-vein thrombosis, 57 (26%) of 223 versus 27 (12%) of 220 (p=0.0003); infections including pneumonia, 35 (16%) of 223 versus 20 (9%) of 220 (p=0.04), and fatigue 33 (15%) of 223 versus 20 (9%) of 220 (p=0.08), respectively.

INTERPRETATION

Lenalidomide plus low-dose dexamethasone is associated with better short-term overall survival and with lower toxicity than lenalidomide plus high-dose dexamethasone in patients with newly diagnosed myeloma.

FUNDING

National Cancer Institute, Rockville, MD, USA.

Multiple myeloma

Multiple myeloma is characterised by clonal proliferation of malignant plasma cells, and mounting evidence indicates that the bone marrow microenvironment of tumour cells has a pivotal role in myeloma pathogenesis. This knowledge has already expanded treatment options for patients with multiple myeloma. Prototypic drugs thalidomide, bortezomib, and lenalidomide have each been approved for the treatment of this disease by targeting both multiple myeloma cells and the bone marrow microenvironment. Although benefit was first shown in relapsed and refractory disease, improved overall response, duration of response, and progression-free and overall survival can be achieved when these drugs are part of first-line regimens. This treatment framework promises to improve outcome not only for patients with multiple myeloma, but also with other haematological malignancies and solid tumours.

Cardiovascular complications of cancer therapy: incidence, pathogenesis, diagnosis, and management

Cancer treatment today employs a combination of chemotherapy, radiotherapy, and surgery to prolong life and provide cure. However, many of these treatments can cause cardiovascular complications such as heart failure, myocardial ischemia/infarction, hypertension, thromboembolism, and arrhythmias. In this article we review the incidence of cardiotoxicity caused by commonly used chemotherapeutic agents as well as discuss the pathogenesis, diagnosis, management, and prevention of these cardiovascular side effects. Cardiotoxicity related to anticancer treatment is important to recognize as it may have a significant impact on the overall prognosis and survival of cancer patients, and it is likely to remain a significant challenge for both cardiologists and oncologists in the future due to an increasing aging population of patients with cancer and the introduction of many new cancer therapies.

Frontline treatment in elderly patients with multiple myeloma

Melphalan-prednisone-thalidomide (MPT) and melphalan-prednisone-bortezomib (MPV) currently appear to be the treatments of choice for a large proportion of elderly multiple myeloma (MM) patients ineligible for autologous stem cell transplantation (ASCT). It seems certain that in the near future cyclophosphamide-thalidomide-dexamethasone, with an attenuated dose of dexamethasone (CTDa), and melphalan-prednisone-lenalidomide (MPR) will also be proved superior to MP, thus providing four therapeutic options in this patient group. These options could lead to more personalized treatment approaches, based on patient comorbidities, as the three novel agents have somewhat different toxicity profiles. MP would be appropriate for only a minority of patients with poor performance status and/or significant comorbidities. Questions regarding the relative efficacy of different melphalan-based regimens or melphalan-based regimens versus dexamethasone-based regimens with low-dose dexamethasone will require further trials. Additionally, the important issue of maintenance treatment needs to be investigated. These new and emerging therapies provide multiple effective treatment options for MM patients and greatly enhanced treatment strategies for clinicians, all offering promise that has been sorely lacking over the past four decades.

Multiple myeloma: management of adverse events

The combination of conventional chemotherapy or dexamethasone with new drugs, such as immunomodulatory agents and proteasome inhibitors, has substantially changed the treatment paradigm of myeloma patients. New drugs have been incorporated in pre-transplant induction regimens and post-transplant consolidation and maintenance strategies for young patients; in elderly patients, standard melphalan and prednisone (MP) plus thalidomide or plus bortezomib are now considered standards of care, and ongoing trials are assessing if lenalidomide plus standard MP or plus low-dose dexamethasone may be other options. The efficacy of these drugs needs to be balanced against their toxicity. Different drugs have a different toxicity profile. The choice for the best treatment strategy for every single patient should be based on results of scientific randomized studies but tailored to account for patient's biological age, comorbidities, and the expected toxicity profile of different regimens. Prompt dose reduction and accurate management of treatment-related toxicity can greatly reduce early discontinuation rate and significantly improve treatment efficacy. This chapter will focus on frequency and management of main adverse events in newly diagnosed and relapsed myeloma patients and will provide guidelines for dose reductions and supportive therapy.

Front-line treatment in younger patients with multiple myeloma

The treatment of newly diagnosed myeloma has evolved rapidly. The choice of initial therapy depends on eligibility for stem cell transplantation, as well as baseline risk factors. Eligibility for transplantation is important since the choice of initial therapy is primarily melphalan-based in patients who are not candidates for transplant, while melphalan-containing regimens are avoided as induction therapy in transplant candidates. An assessment of risk based on independent prognostic markers is important mainly for prognosis but may have some value in choice of initial therapy. For example, bortezomib-based regimens may have particular value in patients with certain high-risk features. This review discusses the current status of front-line therapy in younger patients with myeloma who are candidates for stem cell transplantation.

Mobilization in myeloma revisited: IMWG consensus perspectives on stem cell collection following initial therapy with thalidomide-, lenalidomide-, or bortezomib-containing regimens

The past decade has witnessed a paradigm shift in the initial treatment of multiple myeloma with the introduction of novel agents such as thalidomide, lenalidomide, and bortezomib, leading to improved outcomes. High-dose therapy and autologous stem cell transplantation remains an important therapeutic option for patients with multiple myeloma eligible for the procedure. Before the advent of the novel agents, patients underwent stem cell collection prior to significant alkylating agent exposure, given its potential deleterious effect on stem cell collection. With increasing use of the novel agents in the upfront setting, several reports have emerged raising concerns about their impact on the ability to collect stem cells. An expert panel of the International Myeloma Working Group (IMWG) was convened to examine the implications of these therapies on stem collection in patients with myeloma and to develop recommendations for addressing these issues. Here we summarize the currently available data and present our perspective on the problem and potential options to overcome this problem. Specifically, we recommend early mobilization of stem cells, preferably within the first 4 cycles of initial therapy, in patients treated with novel agents and encourage participation in clinical trials evaluating novel approaches to stem cell mobilization.

Single-agent bortezomib in previously untreated multiple myeloma: efficacy, characterization of peripheral neuropathy, and molecular correlations with response and neuropathy

PURPOSE To assess efficacy and safety of single-agent bortezomib in previously untreated patients with multiple myeloma, investigate prevalence of baseline and treatment-emergent polyneuropathy, and identify molecular markers associated with response and neuropathy. PATIENTS AND METHODS Patients received bortezomib 1.3 mg/m(2) on days 1, 4, 8, and 11, for up to eight 21-day cycles. A subset of patients underwent neurophysiologic evaluation pre- and post-treatment. Bone marrow aspirates were performed at baseline for exploratory whole-genome analyses. Results Among 64 patients, 41% had partial response or better, including 9% complete/near-complete responses; median duration of response was 8.4 months. Response rates did not differ in the presence or absence of adverse cytogenetics. After median follow-up of 29 months, median time to progression was 17.3 months. Median overall survival had not been reached; estimated 1-year survival was 92%. Thirty-two patients successfully underwent optional stem-cell transplantation. Bortezomib treatment was generally well tolerated. At baseline, 20% of patients had sensory polyneuropathy. Sensory polyneuropathy developed during treatment in 64% of patients (grade 3 in 3%), but proved manageable and resolved in 85% within a median of 98 days. Neurologic examination, neurophysiologic testing, and measurements of epidermal nerve fiber densities in 35 patients confirmed pretreatment sensory neuropathy in 20% and new or worsening neuropathy in 63%. Pharmacogenomic analyses identified molecular markers of response and treatment-emergent neuropathy, which will require future study. CONCLUSION Single-agent bortezomib is effective in previously untreated myeloma. Baseline myeloma-associated neuropathy seems more common than previously reported, and bortezomib-associated neuropathy, although a common toxicity, is reversible in most patients.

New generation pharmacotherapy in elderly multiple myeloma patients

BACKGROUND

Observational databases have demonstrated that the overall prognosis of multiple myeloma patients has markedly improved over the past decade, yet the greatest strides have been attained in younger rather than older patients.

OBJECTIVE

To review recent clinical trials that include new generation agents (thalidomide, lenalidomide and bortezomib) and autologous stem cell transplantation in older multiple myeloma patients.

RESULTS

Conventional regimens such as melphalan plus prednisone can be improved with the addition of thalidomide or bortezomib: more patients attain complete and near-complete remission, and progression-free survival rates are nearly doubled. In addition, autologous hematopoietic stem cell transplantation studies show that this treatment approach can be used successfully in selected older myeloma patients in whom the toxicity profile of autotransplant and resulting overall survival may be similar to that obtained in the younger patient group.

CONCLUSIONS

In the advanced-age population, implementation of new therapies results in significant benefits in older as well as younger patients.

Efficacy of melphalan and prednisone plus thalidomide in patients older than 75 years with newly diagnosed multiple myeloma: IFM 01/01 trial

PURPOSE

Until recently, melphalan and prednisone were the standards of care in elderly patients with multiple myeloma. The addition of thalidomide to this combination demonstrated a survival benefit for patients age 65 to 75 years. This randomized, placebo-controlled, phase III trial investigated the efficacy of melphalan and prednisone plus thalidomide in patients older than 75 years with newly diagnosed myeloma.

PATIENTS AND METHODS

Between April 2002 and December 2006, 232 previously untreated patients with myeloma, age 75 years or older, were enrolled and 229 were randomly assigned to treatment. All patients received melphalan (0.2 mg/kg/d) plus prednisone (2 mg/kg/d) for 12 courses (day 1 to 4) every 6 weeks. Patients were randomly assigned to receive 100 mg/d of oral thalidomide (n = 113) or placebo (n = 116), continuously for 72 weeks. The primary end point was overall survival.

RESULTS

After a median follow-up of 47.5 months, overall survival was significantly longer in patients who received melphalan and prednisone plus thalidomide compared with those who received melphalan and prednisone plus placebo (median, 44.0 v 29.1 months; P = .028). Progression-free survival was significantly prolonged in the melphalan and prednisone plus thalidomide group (median, 24.1 v 18.5 months; P = .001). Two adverse events were significantly increased in the melphalan and prednisone plus thalidomide group: grade 2 to 4 peripheral neuropathy (20% v 5% in the melphalan and prednisone plus placebo group; P < .001) and grade 3 to 4 neutropenia (23% v 9%; P = .003).

CONCLUSION

This trial confirms the superiority of the combination melphalan and prednisone plus thalidomide over melphalan and prednisone alone for prolonging survival in very elderly patients with newly diagnosed myeloma. Toxicity was acceptable.

Phase II and pharmacokinetic study of thalidomide in Japanese patients with relapsed/refractory multiple myeloma

To obtain approval from the Ministry of Health, Labor and Welfare of Japan, a phase II study was conducted to assess the pharmacokinetics and pharmacodynamics of thalidomide along with its efficacy and safety in Japanese patients with multiple myeloma. Between 2005 and 2006, 42 patients were enrolled, and 37 patients met eligibility criteria. Of the 37 patients, 3 were excluded from efficacy analysis because of short duration of thalidomide administration (<4 weeks). The overall response rate was 35.3% (12/34), including partial response of 14.7% (5/34) and minimal response of 20.6% (7/34). The adverse events observed in high frequency (>40%) were leukopenia, neutropenia, drowsiness, dry mouth, and constipation. Grade 3 neutropenia was observed in nine cases. Peripheral neuropathy and eruption were observed in about one-quarter of the patients. Deep vein thrombosis was not observed. At a single oral dose of thalidomide (100 mg), the C (max) was 1.68 +/- 0.41 microg/ml, T (max) was 4.54 +/- 1.71 h, T (1/2) was 4.86 +/- 0.44 h, and AUC was 15.87 +/- 3.05 microg h/ml. Low-dose thalidomide was an effective and tolerable treatment for Japanese patients with relapsed/refractory myeloma. Leukopenia and neutropenia were the most serious adverse events. The pharmacokinetics was similar to those observed in Caucasian patients.

Emerging combination treatment strategies containing novel agents in newly diagnosed multiple myeloma

Treatment strategies for multiple myeloma have changed substantially over the past 10 years following the introduction of bortezomib and the immunomodulatory drugs thalidomide and lenalidomide. In the front-line setting, combination regimens incorporating these novel agents are demonstrating substantial activity, which is translating into improved outcomes compared with previous standards of care. Response rates and depth of response that were previously only seen with high-dose therapy plus stem-cell transplantation (HDT-SCT) can now be achieved with new induction regimens utilizing these novel agents. This has raised the need for trials that will determine the clinical benefit of early SCT in patients that have already achieved a high quality of response. Here, we review the improvements in response and outcome that are seen with these novel-agent regimens, both as induction therapy prior to HDT-SCT and in non-transplant patients, and highlight the latest data from key studies of various novel combinations, including regimens featuring bortezomib plus thalidomide or lenalidomide. We also review data on response and outcomes in patients with poor prognostic characteristics that indicate that the adverse impact typically seen with these factors may be overcome using novel-agent therapy.

Initial therapy in multiple myeloma: investigating the new treatment paradigm

The development of three novel chemotherapeutic agents - thalidomide, lenalidomide, and bortezomib - has resulted in a fundamental shift in the management of multiple myeloma. Despite this tremendous advancement, the selection of initial treatment must still be made with a degree of uncertainty as a true standard therapy has yet to be established. Although challenging, the relative abundance of therapeutic options, when taken into consideration with unique patient characteristics, creates the potential for individualization of care.For patients eligible for autologous stem cell transplantation, various combinations of novel agents with dexamethasone or traditional chemotherapy have supplanted the previous standard regimen consisting of vincristine, doxorubicin, and dexamethasone. In elderly patients or others that are deemed ineligible for the transplant procedure, the addition of a novel agent to melphalan-prednisone has demonstrated significant improvements in response rates. Due to the immaturity of the available data, it is perhaps best to regard the era of novel agents with a degree of rational enthusiasm, as the ultimate impact on patient care remains undetermined. Although further research is clearly implicated, recent advancements have resulted in significant progress toward obtaining optimum outcomes in a historically challenging disease.

Role of thalidomide in previously untreated patients with multiple myeloma

Thalidomide represents one of the most relevant therapeutic advances for patients with multiple myeloma over the last 10 years. Despite some toxicities, it has demonstrated significant efficacy in elderly patients, as well as in the setting of younger subjects receiving autologous stem cell transplantation. Here, we report and discuss the clinical results achieved with thalidomide alone or in combination with dexamethasone or other drugs, such as melphalan, cyclophosphamide, doxorubicin and bortezomib, in previously untreated myeloma patients.

Reversibility of symptomatic peripheral neuropathy with bortezomib in the phase III APEX trial in relapsed multiple myeloma: impact of a dose-modification guideline

The frequency, characteristics and reversibility of bortezomib-associated peripheral neuropathy were evaluated in the phase III APEX (Assessment of Proteasome Inhibition for Extending Remissions) trial in patients with relapsed myeloma, and the impact of a dose-modification guideline on peripheral neuropathy severity and reversibility was assessed. Patients received bortezomib 1.3 mg/m(2) (days 1, 4, 8, 11, eight 21-d cycles, then days 1, 8, 15, 22, three 35-d cycles); bortezomib was held, dose-reduced or discontinued depending on peripheral neuropathy severity, according to a protocol-specified dose-modification guideline. Overall, 124/331 patients (37%) had treatment-emergent peripheral neuropathy, including 30 (9%) with grade >or=3; incidence and severity were not affected by age, number/type of prior therapies, baseline glycosylated haemoglobin level, or diabetes history. Grade >or=3 incidence appeared lower versus phase II trials (13%) that did not specifically provide dose-modification guidelines. Of patients with grade >or=2 peripheral neuropathy, 58/91 (64%) experienced improvement or resolution to baseline at a median of 110 d, including 49/72 (68%) who had dose modification versus 9/19 (47%) who did not. Efficacy did not appear adversely affected by dose modification for grade >or=2 peripheral neuropathy. Bortezomib-associated peripheral neuropathy is manageable and reversible in most patients with relapsed myeloma. Dose modification using a specific guideline improves peripheral neuropathy management without adversely affecting outcome.

How to treat a newly diagnosed young patient with multiple myeloma

Survival rates of young patients with myeloma have increased markedly in the last decade, mainly due to the use of autologous stem cell transplantation (ASCT) and new, highly efficient rescue treatments. In order to improve the survival of newly diagnosed young patients further, the next steps need to focus on increasing the activity of upfront or debulking regimens, improving the efficacy of ASCT, mainly through the conditioning regimen, and increasing the duration of responses through more effective maintenance or consolidation therapies. Nevertheless, this approach is being challenged by the favorable results obtained with long-term treatment with novel agents and the possibility of reserving the ASCT until relapse. Allogeneic transplantation in newly diagnosed patients should be considered as an investigational procedure and used only in well-designed clinical trials. This review covers the new strategies that are currently under investigation with the aim of optimizing the outcome for newly diagnosed young patients with myeloma.

How to treat elderly patients with multiple myeloma: combination of therapy or sequencing

Patients with multiple myeloma aged older than 65 years have traditionally received an oral regimen combining melphalan and prednisone (MP). The introduction of novel agents, such as immunomodulatory drugs and proteasome inhibitors, has substantially changed the treatment paradigm of this disease. Five randomized phase III studies, comparing MP plus thalidomide (MPT) versus MP, have shown that MPT increased time to progression (TTP); however, only two of these five studies showed improvement in overall survival (OS). One randomized study has shown that MP plus bortezomib (MPV) increases both TTP and OS compared with MP. Both MPT and MPV are now regarded as the new standards of care for elderly patients. Other promising results have been reported with MP plus lenalidomide or lenalidomide plus dexamethasone, or the combination of cyclophosphamide, thalidomide, and dexamethasone. Reduced-intensity transplantation can be an option for some patients, especially when novel agents are incorporated into pre-transplant induction and post-transplant consolidation. For patients aged older than 75 years a gentler approach should be used, and doses of standard MPT or MPV should be reduced. An accurate management of treatment-related adverse events with prompt dose-reduction can greatly reduce the rate of early discontinuation and significantly improve treatment efficacy. The choice of treatment should be tailored according to the patient’s biologic age and comorbidities, and the expected toxicity profile of the regimen.

Primary malignant tumors of the spine

Primary malignant tumors of the spine account for less than 5% of primary bone tumors. Data from the SEER program suggest that the most common bone sarcomas are osteosarcoma, chondrosarcoma, Ewing's sarcoma, chordoma, and malignant fibrous histiocytoma/fibrosarcoma. During the last two decades, tremendous progress has been made in clinical aspects, surgical approaches, and reconstruction with instrumentation at all levels of the spine. Stabilization procedures, including vertebroplasty and kyphoplasty, have further allowed palliation of pain and symptom relief from compression fractures. Improved radiation techniques have offered the potential for improved local control. This article reviews the changes in surgical philosophy in the management of malignant spinal tumors during the past two decades.

Consolidation therapy with bortezomib/lenalidomide/ dexamethasone versus bortezomib/dexamethasone after a dexamethasone-based induction regimen in patients with multiple myeloma: a randomized phase III trial

In recent years, we have seen tremendous progress in our ability to achieve durable responses in patients with multiple myeloma. At the center of this progress, we have the development of 2 unrelated classes of drugs: proteasome inhibitors such as bortezomib and immunomodulatory drugs such as thalidomide and lenalidomide. The depth and durability of responses attained with these agents in the first-line setting has raised the possibility that they may be considered primary therapy. The Eastern Cooperative Oncology Group E1A05 clinical trial addresses the potential role of bortezomib and dexamethasone (VD) or VD plus lenalidomide (VRD) as primary first-line therapy. This clinical trial enrolls patients who have completed a dexamethasone-based induction (excluding patients using bortezomib). Assuming that most patients entering this clinical trial have been previously treated with thalidomide or lenalidomide, the trial will test whether switching to a proteasome inhibitor (VD arm) versus adding a proteasome inhibitor (VRD) results in superior longterm disease control. Patients entering this clinical trial will have deferred stem cell transplantation until the time of relapse. The primary endpoint of the trial is progression-free survival. By using an alkylator-free consolidation and reserving stem cell transplantation until the time of relapse, we hope that these treatment strategies will further prolong the survival of patients with myeloma.

Treatment of patients with myeloma with comorbid conditions: considerations for the clinician

Patients with multiple myeloma (MM) frequently present with serious comorbidities such as renal impairment and/or diabetes. Treatment of these patient subsets poses a greater challenge: renal dysfunction can alter drug clearance leading to increased toxicity, and commonly used regimens can induce or exacerbate hyperglycemia. In recent years, novel targeted therapies have broadened and improved treatment options for all patients with MM. With these advancements, clinical trials are beginning to report benefit in patients with renal impairment. Furthermore, steroid-sparing and steroid-free regimens have proven highly efficacious and are predicted to improve options for patients with diabetes. This review will highlight recent trials evaluating novel regimens that promise to improve the standard of care for patients with MM with significant comorbidity.

Treatment of newly diagnosed myeloma

The introduction of thalidomide, bortezomib and lenalidomide has dramatically changed the treatment paradigm of multiple myeloma (MM). In patients eligible for autologous stem cell transplant (ASCT), combinations including thalidomide/dexamethasone (Thal/Dex) or bortezomib/dexamethasone (Bort/Dex) or lenalidomide/dexamethasone (Rev/Dex) have been introduced as induction regimens in patients eligible for ASCT. New induction regimens have significantly increased complete response rate before and after ASCT with a positive impact on progression-free survival. Maintenance therapy with thalidomide, under investigation with lenalidomide, may further prolong remission duration. In patients not eligible for ASCT, randomized studies have shown that melphalan, prednisone, thalidomide (MPT) and melphalan, prednisone and bortezomib (MPV) are both superior to melphalan and prednisone (MP), and are now considered standard of care. Ongoing trials will soon assess if MP plus lenalidomide may be considered an attractive option. More complex regimens combining thalidomide or bortezomib or lenalidomide with cyclophosphamide or doxorubicin have been also tested. In small cohorts of patients bortezomib or lenalidomide may overcome the poor prognosis induced by deletion 13 or translocation t(4;14) or deletion 17p13. If these data will be confirmed, a cytogenetically risk-adapted strategy might become the most appropriate strategy.

Thalidomide-dexamethasone compared with melphalan-prednisolone in elderly patients with multiple myeloma

We compared thalidomide-dexamethasone (TD) with melphalan-prednisolone (MP) in 289 elderly patients with multiple myeloma (MM). Patients received either thalidomide 200 mg plus dexamethasone 40 mg, days 1 to 4 and 15 to 18 on even cycles and days 1 to 4 on odd cycles, during a 28-day cycle or to melphalan 0.25 mg/kg and prednisolone 2 mg/kg orally on days 1 to 4 during a 28- to 42-day cycle. Patients achieving stable disease or better were randomly assigned to maintenance therapy with either thalidomide 100 mg daily and 3 MU interferon alpha-2b thrice weekly or to 3 MU interferon alpha-2b thrice weekly only. TD resulted in a higher proportion of complete and very good remissions (26% vs 13%; P= .006) and overall responses (68% vs 50%; P= .002) compared with MP. Time to progression (21.2 vs 29.1 months; P= .2), and progression-free survival was similar (16.7 vs 20.7 months; P= .1), but overall survival was significantly shorter in the TD group (41.5 vs 49.4 months; P= .024). Toxicity was higher with TD, particularly in patients older than 75 years with poor performance status. The study was registered at ClinicalTrials.gov as NCT00205751.

Thalidomide plus dexamethasone as primary therapy for newly diagnosed patients with multiple myeloma

Thalidomide with dexamethasone (thal-dex) is an active therapy for patients with relapsed or refractory multiple myeloma (MM). In this Practice Point, we discuss the findings of a trial by Rajkumar et al. that aimed to compare the response rate, time to progression and progression-free survival among previously untreated patients with MM who received either thal-dex or placebo plus dexamethasone. The thal-dex regimen was associated with a significantly higher response rate at the expense of more-frequent adverse effects, in particular deep-vein thrombosis, which occurred in almost 20% of patients. Median time to progression was three times longer with thal-dex than with placebo plus dexamethasone, but was shorter, however, than the time to progression observed in studies in which thalidomide or bortezomib was added to melphalan and prednisone. Nevertheless, thal-dex is a convenient oral and relatively inexpensive non-myelosuppressive regimen, which can be used in patients with previously untreated MM.

Targeted inhibition of interleukin-6 with CNTO 328 sensitizes pre-clinical models of multiple myeloma to dexamethasone-mediated cell death

Interleukin (IL)-6-mediated signalling attenuates the anti-myeloma activity of glucocorticoids (GCs). We therefore sought to evaluate whether CNTO 328, an anti-IL-6 monoclonal antibody in clinical development, could enhance the apoptotic activity of dexamethasone (dex) in pre-clinical models of myeloma. CNTO 328 potently increased the cytotoxicity of dex in IL-6-dependent and -independent human myeloma cell lines (HMCLs), including a bortezomib-resistant HMCL. Isobologram analysis revealed that the CNTO 328/dex combination was highly synergistic. Addition of bortezomib to CNTO 328/dex further enhanced the cytotoxicity of the combination. Experiments with pharmacologic inhibitors revealed a role for the p44/42 mitogen-activated protein kinase pathway in IL-6-mediated GC resistance. Although CNTO 328 alone induced minimal cell death, it potentiated dex-mediated apoptosis, as evidenced by increased activation of caspases-8, -9 and -3, Annexin-V staining and DNA fragmentation. The ability of CNTO 328 to sensitize HMCLs to dex-mediated apoptosis was preserved in the presence of human bone marrow stromal cells. Importantly, the increased activity of the combination was also seen in plasma cells from patients with GC-resistant myeloma. Taken together, our data provide a strong rationale for the clinical development of the CNTO 328/dex regimen for patients with myeloma.