VAD-based regimens as primary treatment for multiple myeloma

Importance of achieving a complete response in multiple myeloma, and the impact of novel agents

The goal of treatment for multiple myeloma (MM) is to improve patients' long-term outcomes. One important factor that has been associated with prolonged progression-free and overall survival is the quality of response to treatment, particularly achievement of a complete response (CR). There is extensive evidence from clinical studies in the transplant setting in first-line MM demonstrating that CR or maximal response post-transplant is significantly associated with prolonged progression-free and overall survival, with some studies demonstrating a similar association with postinduction response. Supportive evidence is also available from studies in the nontransplant and relapsed settings. With the introduction of bortezomib, thalidomide, and lenalidomide, higher rates of CR are being achieved in both first-line and relapsed MM compared with previous chemotherapeutic approaches, thereby potentially improving long-term outcomes. While standard CR by established response criteria has been shown to have differential prognostic impact compared with lesser responses, increasingly sensitive analytic techniques are now being explored to define more stringent degrees of CR or elimination of minimal residual disease (MRD), including multiparameter flow cytometry and polymerase chain reaction. Demonstrating eradication of MRD by these techniques has already been shown to predict for improved outcomes. Here, we review the prognostic significance of achieving CR in MM and highlight the importance of CR as an increasingly realizable goal at all stages of treatment. We discuss clinical management issues and provide recommendations relevant to practicing oncologists, such as the routine use of sensitive techniques for assessment of disease status to inform evidence-based decisions on optimal patient management.

Advances in treatment for relapses and refractory multiple myeloma

Recent advances in the treatment of multiple myeloma have resulted in improved response rates and overall survival in patients with multiple myeloma. These advances are largely due to thalidomide-, lenalidomide-, and bortezomib-based combinations that have improved response rates, not only in patients with untreated disease, but also in those with relapsed and/or refractory myeloma, in some cases producing response rates up to 85%. Eventually, however, nearly all patients relapse, emphasizing a continuing role for the introduction of investigational agents that overcome drug resistance. This article will review the current role for thalidomide, lenalidomide, and bortezomib-based combinations, as well as some preliminary findings for promising investigational agents currently in clinical trials for patients with relapsed and/or refractory disease.

Current multiple myeloma treatment strategies with novel agents: a European perspective

The treatment of multiple myeloma (MM) has undergone significant developments in recent years. The availability of the novel agents thalidomide, bortezomib, and lenalidomide has expanded treatment options and has improved the outcome of patients with MM. Following the introduction of these agents in the relapsed/refractory setting, they are also undergoing investigation in the initial treatment of MM. A number of phase III trials have demonstrated the efficacy of novel agent combinations in the transplant and nontransplant settings, and based on these results standard induction regimens are being challenged and replaced. In the transplant setting, a number of newer induction regimens are now available that have been shown to be superior to the vincristine, doxorubicin, and dexamethasone regimen. Similarly, in the front-line treatment of patients not eligible for transplantation, regimens incorporating novel agents have been found to be superior to the traditional melphalan plus prednisone regimen. Importantly, some of the novel agents appear to be active in patients with high-risk disease, such as adverse cytogenetic features, and certain comorbidities, such as renal impairment. This review presents an overview of the most recent data with these novel agents and summarizes European treatment practices incorporating the novel agents.

Bortezomib

The ubiquitin-mediated degradation of proteins in numerous cellular processes, such as turnover and quality control of proteins, cell cycle and apoptosis, transcription and cell signaling, immune response and antigen presentation, and inflammation and development makes the ubiquitin-proteosome systems a very interesting target for various therapeutic interventions. Proteosome inhibitors were first synthesized as tools to probe the function and specificity of this particle's proteolytic activities. Most synthetic inhibitors rely on a peptide base, which mimics a protein substrate, attached at a COOH terminal "warhead". Notable warheads include boronic acids, such as Bortezomib and epoxyketones, such as carfilzomib. A variety of natural products also inhibit the proteosome that are not peptide-based, most notably lactacystin, that is related to NPI-0052, or salinosporamide A, another inhibitor in clinical trials. The possibility that proteosome inhibitors could be drug candidates was considered after studies showed that they induced apoptosis in leukemic cell lines. The first proteasome inhibitor in clinical application, Bortezomib showed activity in non small cell lung and androgen-independent prostate carcinoma, as well as MM and mantle cell and follicular non-Hodgkin's lymphoma. It is now lincensed for the treatment of newly diagnosed as well as relapsed/progressive MM and has had a major impact on the improvement in the treatment of MM in the last few years.

Lenalidomide plus dexamethasone versus thalidomide plus dexamethasone in newly diagnosed multiple myeloma: a comparative analysis of 411 patients

The objective of this case-control study was to compare the efficacy and toxicity of lenalidomide plus dexamethasone (len/dex) versus thalidomide plus dexamethasone (thal/dex) as initial therapy for newly diagnosed myeloma. We retrospectively studied 411 newly diagnosed patients treated with len/dex (228) or thal/dex (183) at the Mayo Clinic. The differences were similar in a matched-pair analysis that adjusted for age, sex, transplantation status, and dexamethasone dose. The proportions of patients achieving at least a partial response to len/dex and thal/dex were 80.3% versus 61.2%, respectively (P < .001); very good partial response rates were 34.2% and 12.0%, respectively (P < .001). Patients receiving len/dex had longer time to progression (median, 27.4 vs 17.2 months; P = .019), progression-free survival (median, 26.7 vs 17.1 months; P = .036), and overall survival (median not reached vs 57.2 months; P = .018). A similar proportion of patients in the 2 groups experienced at least one grade 3 or 4 adverse event (57.5% vs 54.6%, P = .568). Main grade 3 or 4 toxicities of len/dex were hematologic, mainly neutropenia (14.6% vs 0.6%, P < .001); the most common toxicities in thal/dex were venous thromboembolism (15.3% vs 9.2%, P = .058) and peripheral neuropathy (10.4% vs 0.9%, P < .001). Len/dex appears well-tolerated and more effective than thal/dex. Randomized trials are needed to confirm these results.

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.

Development of Multiple Myeloma in a Patient with Chronic Myeloid Leukemia While on Treatment with Imatinib Mesylate for 65 Months

The simultaneous occurrence of multiple myeloma (MM) and chronic myeloid leukemia (CML) is an extremely rare event that has been reported in only eight cases in the literature. We report here on only the third case of the development of MM in a patient with CML on treatment with imatinib mesylate, and to our knowledge, this is the first case in a patient who received imatinib as first-line treatment.

The development and pharmacology of proteasome inhibitors for the management and treatment of cancer

The ubiquitin-proteasome complex is an important molecular target for the design of novel chemotherapeutics. This complex plays a critical role in signal transduction pathways important for tumor cell growth and survival, cell-cycle control, transcriptional regulation, and the modulation of cellular stress responses to endogenous and exogenous stimuli. The sensitivity of transformed cells to proteasome inhibitors and the successful design of treatment protocols with tolerable, albeit narrow, therapeutic indices have made proteasome inhibition a viable strategy for cancer treatment. Clinical validation of the proteasome as a molecular target was achieved with the approval of bortezomib, a boronic acid proteasome inhibitor, for the treatment of multiple myeloma and mantle cell lymphoma. Several "next-generation" proteasome inhibitors (carfilzomib and PR-047, NPI-0052, and CEP-18770) representing distinct structural classes (peptidyl epoxyketones, beta-lactones, and peptidyl boronic acids, respectively), mechanisms of action, pharmacological and pharmacodynamic activity profiles, and therapeutic indices have now entered clinical development. These agents may expand the clinical utility of proteasome inhibitors for the treatment of solid tumors and for specific non-oncological, i.e., inflammatory disease, indications as well. This chapter addresses the biology of the proteasome, the medicinal chemistry and mechanisms of action of proteasome inhibitors currently in clinical development, the preclinical and clinical pharmacological and safety profiles of bortezomib and the newer compounds against hematological and solid tumors. Future directions for research and other applications for this novel class of therapeutics agents are considered in this chapter.

Initial cytoreductive treatment with thalidomide plus bolus vincristine/doxorubicin and reduced dexamethasone followed by autologous stem cell transplantation for multiple myeloma

BACKGROUND

High-dose chemotherapy supported by autologous stem cell transplantation (ASCT) after combined chemotherapy with infusional vincristine/doxorubicin plus dexamethasone is effective in multiple myeloma (MM). Outpatient treatment with bolus vincristine/doxorubicin infusion plus dexamethasone is convenient and has acceptable efficacy and toxicity for MM. Thalidomide has recently been shown to have significant antimyeloma activity. We assessed the efficacy and toxicity of the combination of bolus vincristine/doxorubicin and reduced dose dexamethasone with thalidomide (T-bVAd), administered on an outpatient basis, in untreated MM.

PATIENTS AND METHODS

Twenty-six patients prospectively received T-bVAd, consisting of intravenous (i.v.) vincristine 0.4 mg plus doxorubicin 9 mg/m(2), administered as a single bolus on days 1 to 4, dexamethasone 20 mg per os daily for 4 days, and thalidomide 200 mg/day at bedtime. Response assessment was conducted after each 4-week treatment cycle. Patients who achieved response were allowed to proceed to high-dose chemotherapy with ASCT.

RESULTS

On an intention-to-treat basis, 23 of the 26 patients (88%) responded to treatment, with 16 (61%) achieving complete response (CR), 2 (8%) very good partial response (VGPR) and 5 (19%) partial response. Only three patients (12%) were rated as non-responders. Grade 3 and 4 hematologic toxicities consisted of neutropenia (13%), febrile neutropenia (6%), and thrombocytopenia (4%), without significant nonhematologic events. Of the 23 patients who showed response, 7 proceeded to single ASCT and 9 to tandem ASCT. With median follow-up time of 15.3 months (range, 9-25 months), median event free survival (EFS) and overall survival (OS) have not been reached yet, and OS and EFS rates for patients who achieved complete response after T-bVAd regimen were significantly higher than patients not.

CONCLUSIONS

Induction therapy with T-bVAd, administered as an outpatient regimen, was efficient and relatively well tolerated in the treatment of MM.

Combination regimens using doxorubicin and pegylated liposomal doxorubicin prior to autologous transplantation in multiple myeloma

Doxorubicin and pegylated liposomal doxorubicin are key compounds of several induction regimens used prior to autologous stem cell transplantation in patients with de novo multiple myeloma, such as vincristine, doxorubicin, dexamethasone (VAD), vincristine, pegylated liposomal doxorubicin/Doxil, dexamethasone (DVd) or PS-341/bortezomib, doxorubicin, dexamethasone (PAD). The aim of this article is to summarize the more recent data available on the efficacy of these combinations and to discuss their role as part of initial therapy.

CR represents an early index of potential long survival in multiple myeloma

To assess the impact of CR on survival in multiple myeloma. Retrospective evaluation of response and survival among 758 consecutive patients with multiple myeloma treated at a single center, of whom 395 patients received intensive therapy supported by autologous stem cells within the first year. Survival times were calculated after 1 and 2 years from the start of chemotherapy. On the basis of the response status after a 2-year landmark, the subsequent median survival was 9.7 years for patients with CR, 4.4 years for those with PR and 2.7 years for patients with NR (P<0.001). Longer survival was attributed in part to intensive therapy that converted the myeloma of 67% of patients with NR to PR or CR, and induced CR in 26% of patients with PR. Intensive therapy did not prolong survival for patients with CR after primary therapy. For patients with multiple myeloma, Cox regression analyses showed that CR was the dominant prognostic factor for long survival, followed by stage I disease, PR and intensive treatment as independent factors. A cure fraction of 2% was identified for nine patients who have remained in CR >10 years.

Role of combination bortezomib and pegylated liposomal doxorubicin in the management of relapsed and/or refractory multiple myeloma

The first in class proteasome inhibitor bortezomib (B) received its initial regulatory approval for therapy of patients with multiple myeloma (MM) in the relapsed/refractory setting. Modulation of proteasome function, however, is also a rational strategy for chemosensitization, and a variety of agents have shown synergistic activity with bortezomib pre-clinically, including anthracyclines. This formed the basis for evaluation of a regimen of bortezomib with pegylated liposomal doxorubicin (PLD). PLD+B, in a phase I study, induced a predictable and manageable toxicity profile, and showed encouraging anti-MM activity. In a recent international, randomized phase III trial, PLD+B demonstrated a superior overall response rate and response quality compared to bortezomib alone, as well as a longer time to progression, duration of response, progression-free survival, and overall survival. Sub-analyses revealed benefits in almost all clinically relevant subgroups, including several which would be considered to have high-risk disease. These findings have led to the establishment of the PLD+B regimen as one of the standards of care for patients with relapsed and/or refractory myeloma. Efforts are now underway to build on this combination further by adding other active anti-myeloma agents. In this review, we will discuss the role of PLD+B as an important addition to our therapeutic armamentarium for patients with MM.

Does mobilization for autologous stem cell transplantation damage stromal layer formation?

Autologous hematopoietic stem cell transplantation (HSCT) has proved efficient to treat hematological malignancies. However, some patients fail to mobilize HSCs. It is known that the microenvironment may undergo damage after allogeneic HSCT. However little is known about how chemotherapy and growth factors contribute to this damage. We studied the stromal layer formation (SLF) and velocity before and after HSC mobilization, through long-term bone marrow culture from 22 patients and 10 healthy donors. Patients' SLF was similar at pre- (12/22) and post-mobilization (9/20), however for controls this occurred more at pre-mobilization (9/10; p=0.03). SLF velocity was higher at pre than post-mobilization in both groups. Leukemias and multiple myeloma showed faster growth of SLF than lymphomas at post-mobilization, the latter being similar to controls. These findings could be explained by less uncommitted HSC in controls than patients at post-mobilization. Control HSCs may migrate more in response to mobilization, resulting in a reduced population by those cells.

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.

The role of high-dose chemotherapy followed by peripheral blood stem cell transplantation for the treatment of multiple myeloma

The management of multiple myeloma has changed significantly over the past 10 years. The results obtained with conventional chemotherapy were disappointing; however the use of high dose therapy (HDT) and stem cell transplantation has significantly improved survival. Autologous, allogeneic and tandem transplantation, along with different conditioning regimens, have been studied in an attempt to optimise and further improve outcomes. This review summarises the role of stem cell transplantation in multiple myeloma. The advent of novel therapies such as thalidomide, lenalidomide and bortezomib have started to redefine the role of peripheral stem cell transplantation, however, further study is needed to better understand how to most effectively use these agents in multiple myeloma in conjunction with HDT.

Bortezomib in multiple myeloma

BACKGROUND

Bortezomib is a novel, first-in-class proteasome inhibitor that has improved outcomes in multiple myeloma, with manageable toxicities.

OBJECTIVE

To summarise the chemistry, pharmacokinetics and metabolism of bortezomib, and review its clinical efficacy and toxicity, including use in elderly patients, use in patients with renal impairment and/or a poor prognosis, and effects on bone metabolism.

METHODS

Literature search of bortezomib studies (within 10 years) and recent congress abstracts.

RESULTS/CONCLUSIONS

Bortezomib has improved response rates, overall survival, and time to progression in relapsed or refractory disease, both as a single agent and as part of combination regimens. Promising results have also been reported with bortezomib combinations in frontline induction therapy. Patient subgroups where conventional approaches are inappropriate may also benefit, thereby expanding the therapeutic armamentarium against this debilitating disease.

Pulmonary embolism in a patient with multiple myeloma receiving thalidomide-dexamethasone therapy

Massive pulmonary embolism is an uncommon complication of multiple myeloma treated with thalidomide-dexamethasone regimen. In 2006, multiple myeloma was diagnosed in a 72-year-old man, who received thalidomide-dexamethasone therapy. In January 2007, echocardiography and computerized tomography identified massive pulmonary embolism in the pulmonary arteries and a deep vein thrombus of the right leg. The patient also had an elevated concentration of B-type natriuretic peptide. After heparinization and warfarin therapy, the patient's condition improved. This is the first report of a patient with a rare complication of pulmonary embolism from thalidomide-treated multiple myeloma.

Treatment of newly diagnosed multiple myeloma

Multiple myeloma (MM) is the second most common oncohematologic disease. Most patients are older than 65 years at diagnosis, and different therapeutic options are available depending on the age of the patient. For those younger than 65 years, autologous stem cell transplantation is the standard of care, whereas in older patients the better choice is conventional chemotherapy. The introduction of thalidomide, bortezomib, and lenalidomide, which target MM cells and the bone marrow microenvironment, has changed the therapeutic options in newly diagnosed patients with MM.

Multiple myeloma

Multiple myeloma is a clonal plasma cell malignancy that accounts for slightly more than 10% of all hematologic cancers. In this paper, we present a historically focused review of the disease, from the description of the first case in 1844 to the present. The evolution of drug therapy and stem-cell transplantation for the treatment of myeloma, as well as the development of new agents, is discussed. We also provide an update on current concepts of diagnosis and therapy, with an emphasis on how treatments have emerged from a historical perspective after certain important discoveries and the results of experimental studies.

Future challenges

Treatment for patients with myeloma has changed unrecognisably over the last two decades and now includes a sequence of treatments including chemotherapy, biological targeted therapy with or without consideration for high-dose therapy (autologous and allogeneic stem cell transplantation for younger and fit patients). As patients can now expect a doubling of median survival and a 20-30% chance of surviving longer than 10 years, the focus of treatment is shifting to long-term quality of life. This article focuses on future challenges facing clinicians treating myeloma and how best we may optimize our resources.

Long-term results of response to therapy, time to progression, and survival with lenalidomide plus dexamethasone in newly diagnosed myeloma

OBJECTIVE

To determine the long-term effects of a combined regimen of lenalidomide and dexamethasone (Rev-Dex) on time to progression, progression-free survival, and overall survival (OS) in patients with multiple myeloma.

PATIENTS AND METHODS

From March 2004 through October 2004, 34 patients were registered for the study. They were treated with 25 mg/d of lenalidomide on days 1 through 21 of a 28-day cycle and 40 mg/d of dexamethasone on days 1 through 4, 9 through 12, and 17 through 20 of each cycle. After 4 cycles of therapy, patients were allowed to discontinue treatment to pursue autologous stem cell transplant (SCT). Treatment beyond 4 cycles was permitted at the physician s discretion.

RESULTS

Thirteen patients proceeded to SCT after initial therapy and were censored at that time point for purposes of calculation of response. Thirty-one patients achieved an objective response, defined as a partial response or better (91%; 95% confidence interval, 79%-98%), with a complete response plus very good partial response rate of 56%. The complete response plus very good partial response among the 21 patients who received Rev-Dex without SCT was 67%. The 2-year progression-free survival rates for patients proceeding to SCT and patients remaining on Rev-Dex were 83% and 59%, respectively; the OS rates were 92% and 90% at 2 years and 92% and 85% at 3 years, respectively. The 3-year OS rate for the whole cohort was 88%.

CONCLUSION

The Rev-Dex regimen is highly active in the treatment of newly diagnosed multiple myeloma. Responses are durable with a low progression rate at 2 years. Randomized trials that incorporate quality-of-life measures are needed to determine if this and other combination regimens are better used early in therapy or should be reserved for later interventions.

Preclinical rationale, mechanisms of action, and clinical activity of anthracyclines in myeloma

Multiple myeloma is an incurable disease for which there are 2 clinical research strategies. One strategy is to focus on managing the disease as a chronic process aiming to minimize the negative impact on survival with minimal or no compromise of the quality of life. The other strategy is to pursue total eradication of the malignant clone, thus achieving cure for the disease. Over the past decade, the myeloma communities have seen several new agents approved for the therapy of multiple myeloma. Although these agents do not result in cure, they target the disease microenvironment, allowing for a better overall response rate and improved quality of response. The latter appears to be influencing the disease outcome in improved progression-free survival, translating into a longer overall survival. Despite the advances in the discovery of immune modulator compounds, chemotherapy continues to be an important part of the myeloma therapeutic armamentarium. Recently, several investigators have explored combining traditional chemotherapeutic agents with proteasome inhibitors and immune modulators.

New therapies in multiple myeloma

The melphalan-prednisone regimen has been considered as standard therapy for patients with multiple myeloma (MM) for many years. Recently, high-dose chemotherapy with stem-cell support has extended progression-free survival and increased overall survival, and it is now considered conventional therapy in younger patients. However, most patients relapse and the salvage treatment is not very effective. New active drugs, including immunomodulatory agents, thalidomide (Thal) and lenalidomide, and the proteasome inhibitor bortezomib, have shown promising anti-myeloma activity. These novel treatments are aimed at overcoming resistance of tumour cells to conventional chemotherapy, acting both directly on myeloma cells and indirectly by blocking the interactions of myeloma cells with their local microenvironment and suppressing growth and survival signals induced by autocrine and paracrine loops in the bone marrow. Thal has been widely studied, mostly in combination regimens in patients with relapsed MM and, more recently, in front-line therapy, showing efficacy in terms of response rate and event-free survival. Bortezomib has been found to possess remarkable activity, especially in combination with other chemotherapeutic agents, in relapsed/refractory and newly diagnosed MM, as well as in patients presenting adverse prognostic factors. Lenalidomide, in combination with dexamethasone, is showing high overall response rates in relapsed and refractory MM and promising results also in first-line therapy. In this paper, the results of the most significant trials with Thal, bortezomib and lenalidomide are reported. Several ongoing clinical studies will hopefully allow the identification of the most active combinations capable of improving survival in patients with MM.

Melphalan and its role in the management of patients with multiple myeloma

Melphalan is an alkylating agent approved for the treatment of multiple myeloma and ovarian cancer. The combination of oral melphalan and prednisone was first introduced in the 1960s and remains the standard therapy for elderly multiple myeloma patients. High-dose melphalan followed by autologous stem cell support became the standard treatment for younger patients since the 1990s. The occurrence of drug resistance is the major limiting factor for the long-term success of this therapy, and relapse always occurs. In recent years, advances in the understanding of the pathogenesis of myeloma and the mechanism of drug resistance have led to the development of novel targeted therapies that are able to overcome resistance and show additive or synergistic effects with melphalan. Thalidomide, its immunomodulatory derivative lenalidomide and the proteasome inhibitor bortezomib, in combination with oral melphalan in the elderly and with intravenous melphalan in younger patients, are changing the traditional treatment paradigm of multiple myeloma.

OSU-03012, a Novel Celecoxib Derivative, Is Cytotoxic to Myeloma Cells and Acts through Multiple Mechanisms

PURPOSE

OSU-03012 is a novel celecoxib derivative, without cyclooxygenase-2 inhibitory activity, capable of inducing apoptosis in various cancer cells types, and is being developed as an anticancer drug. We investigated the in vitro activity of OSU-03012 in multiple myeloma (MM) cells.

EXPERIMENTAL DESIGN

U266, ARH-77, IM-9, and RPMI-8226, and primary myeloma cells were exposed to OSU-03012 for 6, 24, or 72 h. Cytotoxicity, caspase activation, apoptosis, and effects on intracellular signaling pathways were assessed.

RESULTS

OSU-03012 was cytotoxic to MM cells with mean LC50 3.69 +/- 0.23 and 6.25 +/- 0.86 micromol/L and at 24 h for primary MM cells and cell lines, respectively. As a known PDK-1 inhibitor, OSU-03012 inhibited the PI3K/Akt pathway with downstream effects on BAD, GSK-3beta, FoxO1a, p70S6K, and MDM-2. However, transfection of MM cells with constitutively active Akt failed to protect against cell death, indicating activity against other pathways is important. Phospho (p)-signal transducers and activators of transcription 3 and p-MAP/ERK kinase 1/2 were down-regulated, suggesting that OSU-03012 also inhibited the Janus-activated kinase 2/signal transducer and activator of transcription 3 and mitogen-activated protein kinase pathways. Although expression of Bcl-2 proteins was unchanged, OSU-03012 also down-regulated survivin and X-linked inhibitor of apoptosis (XIAP), and also induced G2 cell cycle arrest with associated reductions in cyclins A and B. Finally, although OSU-03012 induced cleavage of caspases 3, 8 and 9, caspase inhibition did not prevent cell death.

CONCLUSIONS

We conclude that OSU-03012 has potent activity against MM cells and acts via different mechanisms in addition to phosphoinositide-3-kinase/Akt pathway inhibition. These studies provide rationale for the clinical investigation of OSU-03012 in MM.

VAD-doxil versus VAD-doxil plus thalidomide as initial treatment for multiple myeloma: results of a multicenter randomized trial of the Greek myeloma study group

BACKGROUND

We have previously demonstrated that vincristine, liposomal doxorubicin and dexamethasone (VAD-doxil) is equally effective with VAD-bolus yielding objective response rates of 61% as first-line treatment in multiple myeloma (MM). In a phase II study, the addition of thalidomide to VAD-doxil (TVAD-doxil) proved feasible and increased response rate to 74%. The aim of the present multicenter prospective randomized clinical trial was to compare the efficacy and toxicity of VAD-doxil and TVAD-doxil in previously untreated MM patients.

PATIENTS AND METHODS

We enrolled 232 newly diagnosed MM patients aged <75 years, 115 randomized to VAD-doxil (arm A) and 117 to TVAD-doxil (arm B). Patients in arm A received vincristine 2 mg i.v. and liposomal doxorubicin 40 mg/m(2) i.v., on day 1 and dexamethasone 40 mg p.o. daily on days 1-4, 9-12 and 17-20 for the first cycle and on days 1-4 for the next three cycles. Patients in arm B received additionally thalidomide 200 mg p.o. daily, at bedtime. Treatment was administered every 28 days.

RESULTS

On an intention-to-treat basis, at least partial response was observed, in 62.6% and in 81.2% of patients randomized to arms A and B, respectively (P = 0.003). Progression-free survival (PFS) at 2 years was 44.8% in arm A and 58.9% in arm B (P = 0.013). Overall survival (OS) at 2 years was 64.6% and 77%, in arms A and B, respectively (P = 0.037). Considering overall toxicity, constipation, peripheral neuropathy, dizziness/somnolence, skin rash and edema were significantly higher in arm B compared with arm A (P < 0.01), but grade 3-4 toxicities were low and similar in both arms.

CONCLUSIONS

The addition of thalidomide to VAD-doxil increases response and PFS rates and probably OS in previously untreated myeloma patients. The superiority of efficacy counterbalances the higher overall toxicity of TVAD-doxil.

Current Standards for First-Line Therapy of Multiple Myeloma

Current standards of care for first-line treatment of multiple myeloma are evolving rapidly because of the introduction of regimens based on novel agents with unique mechanisms of action: the proteasome inhibitor bortezomib and the immunomodulatory drugs thalidomide and lenalidomide. These regimens are becoming increasingly widely used, offering substantially greater benefit to patients in terms of higher response rates and, more importantly, prolonged response durations and survival compared with established standard first-line treatment strategies. A notable aspect of many of these emerging treatment options is the very high rates of complete response (CR) reported, previously only seen with transplantation-based strategies. Achievement of CR is prognostic for improved overall survival; therefore, the higher rates and quality of responses seen with the new regimens might substantially improve patient outcomes versus established standards of care. For example, addition of each of the 3 novel agents to melphalan/prednisone results in higher overall response rates and CR rates, as well as prolonged progression-free and overall survival, compared with melphalan/prednisone alone. Similar substantial improvements in response are seen with addition of the 3 agents to single-agent dexamethasone and the use of bortezomib or thalidomide in VAD (vincristine/doxorubicin/dexamethasone)-like regimens, as induction therapies before stem cell transplantation and in patients not proceeding to transplantation. Ultimately, these novel regimens might obviate the need for stem cell transplantation in a sizeable proportion of patients. The emergence of these new therapeutic options appears likely to significantly alter the first-line treatment paradigm for patients with multiple myeloma.

Serum M-spike and transplant outcome in patients with multiple myeloma

High dose therapy with autologous stem cell transplantation (HDT-ASCT) has prolonged survival in patients with multiple myeloma. Patients who achieve a complete response (CR) benefit the most from this form of therapy. Thus, achieving a CR is an important goal of therapy and it will be beneficial if the probability of achieving CR can be determined for any patient before transplant. Here we report that pretransplant monoclonal protein level (M-spike) was found to be an important predictor. Thus, we used knowledge of the rate of M-protein production by myeloma cells together with the clearance of the protein to estimate the pretransplant disease burden. We show that the pretransplant disease burden, based on the M-spike, is the only predictor for achieving CR. A simple function that describes this probability is presented. We also provide an estimate of the rate of tumor regrowth in patients who obtain a CR and in patients who only get a partial response with HDT-ASCT. The significant expansion of myeloma cells after HDT-ASCT is clearly evident. Clinical trials must be designed that take into account these kinetic aspects of the disease.

Pegylated Liposomal Doxorubicin and Immunomodulatory Drug Combinations in Multiple Myeloma: Rationale and Clinical Experience

The availability of new agents for multiple myeloma (MM) provides an opportunity to further improve response rates through the development of new combination regimens. Such new agents include pegylated liposomal doxorubicin (PLD) and the immunomodulatory drugs thalidomide and lenalidomide, all of which have demonstrated efficacy and safety in the treatment of newly diagnosed and relapsed/refractory MM. Based on their complementary mechanisms of action and nonoverlapping toxicity profiles, PLD and the immunomodulatory drugs might provide incremental benefits when used in combined treatment regimens. Thus, they have been evaluated in clinical studies that combine PLD/vincristine/dexamethasone and thalidomide (DVd-T) or PLD/vincristine/dexamethasone and lenalidomide (DVd-R) as well as in a study combining bortezomib with PLD and thalidomide. Results of all these studies have included high overall response rates, with improved rates of complete/near complete response compared with similar regimens that do not include chemotherapy (ie, immunomodulatory drugs plus dexamethasone). This article provides the clinical rationale for the use of PLD in combination with immunomodulatory drugs to treat patients with MM and summarizes the clinical experience with these combinations to date. Notably, the early phase I/II study results have been sufficiently encouraging to warrant further investigation in additional large-scale, phase II/III studies. Future clinical trials should focus on determining the optimal dose and schedule for each of these agents when used in combination and whether the addition of other new agents provides an additional response benefit.

Emerging Data on the Use of Anthracyclines in Combination with Bortezomib in Multiple Myeloma

Since the inception of infusional vincristine/doxorubicin/pulsed dexamethasone (VAD) for the treatment of multiple myeloma, anthracyclines have remained an important class of antimyeloma agents. More recently, the introduction of pegylated liposomal doxorubicin with improved pharmacokinetic characteristics has led to the development of newer anthracycline-containing regimens with improved toxicity profiles. Bortezomib, a first in class reversible inhibitor of the proteasome, has also emerged as an important novel agent for the treatment of multiple myeloma and is currently approved for patients with relapsed/refractory disease progressing after 1 previous therapy. Although both classes of agents have potent proapoptotic activity, they also induce activation of an antiapoptotic prosurvival program that limits their own efficacy, a process known as inducible chemotherapy resistance. Importantly, in preclinical studies, each of these drugs has been shown to attenuate chemotherapy resistance induced by the other, and combinations of the 2 have demonstrated striking synergistic activity. Furthermore, early phase I/II clinical trials have shown impressive activity of pegylated liposomal doxorubicin and conventional doxorubicin in combination with bortezomib in patients with newly diagnosed and relapsed/refractory myeloma. Phase II/III clinical trials evaluating these regimens in patients with newly diagnosed and relapsed/refractory disease have recently completed accrual and will better define the role of these combinations in myeloma therapy. Herein, we review the preclinical data supporting the use of bortezomib with anthracyclines and the promising clinical data with these combinations.

Clinical Benefits and Economic Analysis of Pegylated Liposomal Doxorubicin/Vincristine/Dexamethasone Versus Doxorubicin/Vincristine/Dexamethasone in Patients with Newly Diagnosed Multiple Myeloma

Pegylated liposomal doxorubicin has reduced toxicity compared with conventional doxorubicin. In a noninferiority trial randomizing patients to receive pegylated liposomal doxorubicin 40 mg/m(2) and vincristine 1.4 mg/m(2) (maximum, 2 mg) intravenously on day 1 plus reduced-dose dexamethasone 40 mg orally on days 1-4 (DVd; n = 97) or conventional doxorubicin 9 mg/m(2) per day and vincristine 0.4 mg per day continuous intravenous infusion on days 1-4 plus reduced-dose dexamethasone (VAd; n = 95) for >/= 4 cycles. Treatment was repeated every 4 weeks until maximal response, disease progression, unacceptable toxicity, or until patients underwent transplantation. Treatment cost was estimated by applying standard US costs in 2004 to recorded health-care resource utilization units. Outcome measures included response, toxicity, and treatment cost. Objective response rates (DVd, 44%; VAd, 41%), progression-free survival (hazard ratio, 1.11; P = 0.69), and overall survival (hazard ratio, 0.88; P = 0.67) were similar between treatment groups. DVd was associated with significantly less grade 3/4 neutropenia or neutropenic fever (10% vs. 24%; P = 0.01), less sepsis, antibiotic use, growth factor support, and alopecia, but more hand-foot syndrome. Study drug costs were significantly higher for DVd versus VAd; however, lower costs for drug administration and supportive care more than offset this difference, resulting in nominally lower overall study drug treatment costs for DVd (DVd, $34,442; VAd, $35,846; P = 0.76). The DVd regimen demonstrated similar efficacy and cost with less toxicity and supportive care compared with VAd. This should improve clinical utility and optimize the opportunity for transplantation.

Treatment of newly diagnosed multiple myeloma based on Mayo Stratification of Myeloma and Risk-adapted Therapy (mSMART): consensus statement

Multiple myeloma is a neoplastic plasma cell dyscrasia that on a yearly basis affects nearly 17,000 individuals and kills more than 11,000. Although no cure exists, many effective treatments are available that prolong survival and improve the quality of life of patients with this disease. The purpose of this consensus is to offer a simplified, evidence-based algorithm of decision making for patients with newly diagnosed myeloma. In cases in which evidence is lacking, our team of 18 Mayo Clinic myeloma experts reached a consensus on what therapy could generally be recommended. The focal point of our strategy revolves around risk stratification. Although a multitude of risk factors have been identified throughout the years, including age, tumor burden, renal function, lactate dehydrogenase, beta2-microglobulin, and serum albumin, our group has now recognized and endorsed a genetic stratification and patient functional status for treatment.

The Changing Treatment Paradigm in Patients With Newly Diagnosed Multiple Myeloma: Implications for Nursing

PURPOSE/OBJECTIVES

To review the changing treatment paradigm for newly diagnosed multiple myeloma and its implications for nursing.

DATA SOURCES

Journal articles, textbooks, published research data.

DATA SYNTHESIS

The treatment approaches to newly diagnosed multiple myeloma are varied, and no consensus exists about the best choice of induction therapy prior to high-dose chemotherapy with autologous stem cell transplantation. Novel therapies that have shown strong clinical activity in patients with relapsed or refractory myeloma currently are being explored as first-line therapy with associated higher incidence of serious complications.

CONCLUSIONS

Novel approaches in the treatment of newly diagnosed multiple myeloma may lead to better overall patient survival. Research is ongoing to find ways to improve progression-free and overall survival in patients with multiple myeloma.

IMPLICATIONS FOR NURSING

Oncology nurses play vital roles in the assessment and monitoring of serious complications associated with various therapies for patients with newly diagnosed multiple myeloma. Key responsibilities include safe and effective administration of complex chemotherapeutic regimens, management of side effects, patient and family education, and coordination of a multidisciplinary approach.

Nonmyeloablative unrelated donor hematopoietic cell transplantation to treat patients with poor-risk, relapsed, or refractory multiple myeloma

The purpose of this study was to determine long-term outcome of unrelated donor nonmyeloablative hematopoietic cell transplantation (HCT) in patients with poor-risk multiple myeloma. A total of 24 patients were enrolled; 17 patients (71%) had chemotherapy-refractory disease, and 14 (58%) experienced disease relapse or progression after previous autologous transplantation. Thirteen patients underwent planned autologous transplantation followed 43-135 days later with unrelated transplantation, whereas 11 proceeded directly to unrelated transplantation. All 24 patients were treated with fludarabine (90 mg/m(2)) and 2 Gy of total body irradiation before HLA-matched unrelated peripheral blood stem cell transplantation. Postgrafting immunosuppression consisted of cyclosporine and mycophenolate mofetil. The median follow-up was 3 years after allografting. One patient experienced nonfatal graft rejection. The incidences of acute grades II and III and chronic graft-versus-host disease were 54%, 13%, and 75%, respectively. The 3-year nonrelapse mortality (NRM) was 21%. Complete responses were observed in 10 patients (42%); partial responses, in 4 (17%). At 3 years, overall survival (OS) and progression-free survival (PFS) rates were 61% and 33%, respectively. Patients receiving tandem autologous-unrelated transplantation had superior OS and PFS (77% and 51%) compared with patients proceeding directly to unrelated donor transplantation (44% and 11%) (PFS P value = .03). In summary, for patients with poor-risk, relapsed, or refractory multiple myeloma, cytoreductive autologous HCT followed by nonmyeloablative conditioning and unrelated HCT is an effective treatment approach, with low NRM, high complete remission rates, and prolonged disease-free survival.

Bortezomib in Combination with Pegylated Liposomal Doxorubicin for the Treatment of Multiple Myeloma

Many novel agents and new combinations (including bortezomib, thalidomide, and lenalidomide) have been developed in recent years for the treatment of multiple myeloma (MM), creating major shifts in therapeutic management. Achieving complete response (CR)/near CR (nCR) generally serves as a reliable clinical surrogate for overall treatment outcome, ie, prolonged survival. Indeed, some newer induction regimens are yielding similar median time to disease progression effects compared with transplantation. Thus, it can be a dilemma whether a patient with CR/nCR needs to be subjected to the potential morbidity associated with transplantation after induction therapy. Combining new agents with chemotherapy-based regimens appears to offer higher overall response and CR/nCR rates than similar combinations that do not include chemotherapy. We review the preclinical and clinical rationale for combining bortezomib with pegylated liposomal doxorubicin for the treatment of MM. The synergistic interaction in sensitizing each other toward myeloma cells in vitro and their complementary in vivo activities have justified clinical studies. We summarize data for completed and ongoing phase I/II trials of this combination. To date, results have been sufficiently encouraging to initiate an international, multicenter, randomized, phase III trial comparing bortezomib with or without pegylated liposomal doxorubicin in patients with relapsed/refractory MM. The results of this trial will confirm whether the rationale for combining bortezomib with pegylated liposomal doxorubicin is validated by improved clinical outcome, ie, improved time to progression, for patients with MM.

Advances in oral therapy in the treatment of multiple myeloma

Conventional IV chemotherapy regimens used for induction chemotherapy or salvage therapy in the treatment of multiple myeloma (MM) are cumbersome, with a negative impact on patient quality of life. A number of new oral drugs, including immunomodulatory agents such as thalidomide and lenalidomide, have demonstrated potent antimyeloma activity in relapsed and refractory as well as newly diagnosed MM. Clinically, response rates of 56%-72% have been reported with the combination of thalidomide and dexamethasone in patients with newly diagnosed disease; however, the combination is associated with a higher incidence of side effects, including constipation, somnolence, peripheral neuropathy, and thromboembolic complications. In contrast, preliminary safety and efficacy data from clinical studies of lenalidomide show promise. Response rates as high as 83% have been reported in patients with newly diagnosed MM, and the most common adverse event is manageable myelosuppression, which is reversible with dose reduction. Lenalidomide has different toxicities than thalidomide, exhibiting greater myelosuppression but virtually no constipation, somnolence, or peripheral neuropathy. Oncology nurses play a key role in monitoring patients for side effects and pain control and educating them about emerging treatment options. This article reviews the nursing experience with oral agents in the treatment of MM.

Vincristine, doxorubicin, and dexamethasone or thalidomide plus dexamethasone for newly diagnosed patients with multiple myeloma?

Multiple myeloma (MM) is a malignant plasma cell tumor that is distributed at multiple sites within the bone marrow compartments. High-dose dexamethasone regimens [including vincristine, doxorubicin, and dexamethasone (VAD) chemotherapy] induce rapid responses, and have resulted in improved survival for many patients when followed by intensive therapy with autologous stem cell support early in the disease course. However, VAD have several disadvantages including the need for an intravenous indwelling catheter, which predisposes patients to catheter-related sepsis and thrombosis; most of the activity of VAD was from high-dose dexamethasone component. We enrolled all patients who fulfilled entire criteria for MM during the period between January 1997 and December 2005. The present study is a descriptive, retrospective, longitudinal, and observational one. The frequency of response (CR, VGPR/NCR, and PR) in the group of thalidomide and dexamethasone was 84.3% (CR 18.75% VGPR/NCR 18.75%, and PR 46.8%) being higher than VAD, 55% (CR 16%, VGPR/NCR 5%, and PR 34%). P = 0.0005. In summary, we conclude Thal/dex is an effective therapy in newly diagnosed MM inducing objective responses in over 84.3%.

Phase 2 study of pegylated liposomal doxorubicin, vincristine, decreased-frequency dexamethasone, and thalidomide in newly diagnosed and relapsed-refractory multiple myeloma

OBJECTIVE

To evaluate the efficacy and safety of adding thalidomide to the pegylated liposomal doxorubicin, vincristine, and decreased-frequency dexamethasone (DVd) regimen for multiple myeloma.

PATIENTS AND METHODS

Patients newly diagnosed as having active multiple myeloma and those with relapsed-refractory disease were studied between August 2001 and October 2003. Patients received DVd as previously described. Thalidomide was given at 50 mg/d orally and the dose increased slowly to a maximum of 400 mg/d. At the time of best response, patients received maintenance prednisone, 50 mg orally every other day, and daily thalidomide at the maximum tolerated dose for each patient. The primary end point was the rate of complete responses plus very good partial responses as defined by the European Group for Blood and Marrow Transplantation criteria and the Intergroupe Français du Myélome, respectively.

RESULTS

Of 102 eligible patients, 53 were newly diagnosed as having multiple myeloma, and 49 had been previously treated for multiple myeloma. The complete response plus very good partial response rate was 49% and 45%, with an overall response rate of 87% and 90% for patients with newly diagnosed and previously treated multiple myeloma, respectively. Furthermore, better responses were associated with improved progression-free and overall survival. The most common grade 3 and 4 adverse events were thromboembolic events (25%), peripheral neuropathy (22%), and neutropenia (14%).

CONCLUSIONS

The addition of thalidomide to the DVd regimen significantly improves the response rate and quality of responses compared with the DVd regimen alone. This improvement is associated with longer progression-free and overall survival. The rate of observed quality responses is comparable to responses seen with high-dose therapy.

Advances in oral therapy for multiple myeloma

Conventional intravenous chemotherapy regimens are toxic, cumbersome, and negatively affect patients' quality of life, with oral treatment preferable to most patients with cancer. Multiple myeloma is the second most common haematological malignant disease, but cannot be cured with conventional and high-dose chemotherapy. New oral treatments that target myeloma cells or bone marrow are being developed that are highly effective yet have low toxic effects, such as the immunomodulatory drugs thalidomide and lenalidomide. Several treatments in early development have shown antimyeloma activity, including: CHIR-258, which inhibits fibroblast growth factor receptor 3; NVP-ADW742, which inhibits insulin-like growth factor receptor 1; and PTK787, which inhibits vascular endothelial growth factor. Additional drugs aimed at switching off silenced genes include histone deacetylase inhibitors. The availability of these various oral treatments is hoped to improve regimens that, if used sequentially or in combination, offer the potential of making multiple myeloma a chronic disease, thereby extending patients' lifespans and improving quality of life.

Pegylated liposomal doxorubicin, vincristine, and dexamethasone provide significant reduction in toxicity compared with doxorubicin, vincristine, and dexamethasone in patients with newly diagnosed multiple myeloma: a Phase III multicenter randomized trial

BACKGROUND

Pegylated liposomal doxorubicin has pharmacologic and safety advantages over conventional doxorubicin.

METHODS

For this noninferiority trial, 192 patients with newly diagnosed, active multiple myeloma were randomized to receive either combined pegylated liposomal doxorubicin (40 mg/m(2)) and vincristine (1.4 mg/m(2); maximum, 2.0 mg) as an intravenous infusion on Day 1 plus reduced-dose dexamethasone (40 mg) orally on Days 1-4 (DVd) (n = 97 patients) or combined vincristine (0.4 mg per day) and conventional doxorubicin (9 mg/m(2) per day) as a continuous intravenous infusion on Days 1-4 plus reduced-dose dexamethasone (VAd) (n = 95 patients) for at least 4 cycles. Treatment was repeated every 4 weeks until patients either achieved maximal response, disease progression, or unacceptable toxicity or underwent transplantation. The primary endpoints were response and toxicity.

RESULTS

Objective response rates (DVd, 44%; VAd, 41%), progression-free survival (hazard ratio, 1.11; P = 0.69), and overall survival (hazard ratio, 0.88; P = 0.67) were similar between the treatment groups. However, DVd was associated with significantly less Grade 3/4 neutropenia or neutropenic fever (10% vs. 24%; P = 0.01), a lower incidence of sepsis, and less antibiotic use. Compared with VAd, DVd also significantly decreased the need for central venous access (P < 0.0001) and growth-factor support (P = 0.03) and resulted in less alopecia (20% vs. 44%; P < 0.001) but more hand-foot syndrome (25% vs. 1%; P < 0.001), mainly Grade 1/2.

CONCLUSIONS

The DVd regimen demonstrated similar efficacy with less toxicity and supportive care compared with VAd, which should improve clinical utility and optimize the opportunity for transplantation.