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

Immunomodulatory Agents for Multiple Myeloma

The treatment of multiple myeloma (MM) has undergone a significant paradigm shift in the last 20 years, from conventional chemotherapy to more tumor-specific treatments, based on the interference with pathogenesis of the malignant clone as well as the bone microenvironment [...].

Drug Delivery in Cancer Therapy, Quo Vadis?

The treatment of malignancies has undergone dramatic changes in the past few decades. Advances in drug delivery techniques and nanotechnology have allowed for new formulations of old drugs, so as to improve the pharmacokinetics, to enhance accumulation in solid tumors, and to reduce the significant toxic effects of these important therapeutic agents. Here, we review the published clinical data in cancer therapy of several major drug delivery systems, including targeted radionuclide therapy, antibody-drug conjugates, liposomes, polymer-drug conjugates, polymer implants, micelles, and nanoparticles. The clinical outcomes of these delivery systems from various phases of clinical trials are summarized. The success and limitations of the drug delivery strategies are discussed based on the clinical observations. In addition, the challenges in applying drug delivery for efficacious cancer therapy, including physical barriers, tumor heterogeneity, drug resistance, and metastasis, are discussed along with future perspectives of drug delivery in cancer therapy. In doing so, we intend to underscore that efficient delivery of cancer therapeutics to solid malignancies remains a major challenge in cancer therapy, and requires a multidisciplinary approach that integrates knowledge from the diverse fields of chemistry, biology, engineering, and medicine. The overall objective of this review is to improve our understanding of the clinical fate of commonly investigated drug delivery strategies, and to identify the limitations that must be addressed in future drug delivery strategies, toward the pursuit of curative therapies for cancer.

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

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

Analysis of Common Eligibility Criteria of Randomized Controlled Trials in Newly Diagnosed Multiple Myeloma Patients and Extrapolating Outcomes

BACKGROUND

The performance of multiple myeloma (MM) therapies in a general patient population and specific eligibility criteria that might limit enrollment into randomized controlled trials (RCTs) have not been evaluated in depth. This study aimed to determine if improvements seen with MM therapies in RCTs are reflected in the general patient population and to identify eligibility criteria that can be modified to increase enrollment.

PATIENTS AND METHODS

The Connect MM Registry is a prospective observational cohort study of patients with newly diagnosed MM (NDMM) in the United States. Using common RCT exclusion criteria collected from 16 published studies, patients in the registry were categorized according to their eligibility for inclusion in RCTs.

RESULTS

On the basis of common criteria, 563 of 1406 of registry patients (40.0%) are ineligible for RCTs. Criteria leading to exclusion included M-protein ≤ 1.0 g/dL (25.2%), creatinine > 2.5 mg/dL (13.9%), low absolute neutrophil count (10.0%), and low hemoglobin (9.6%). Significantly more RCT-ineligible versus RCT-eligible patients had hypercalcemia (11.0% vs. 5.5%), elevated creatinine levels (38.9% vs. 6.2%), low hemoglobin levels (59.5% vs. 39.5%), or International Staging System stage III disease (40.1% vs. 22.1%; P < .001 for all comparisons). RCT-ineligible patients had a lower 3-year survival rate than RCT-eligible patients (63% vs. 70%). The incidence of serious adverse events was similar between groups.

CONCLUSION

Of patients with NDMM enrolled in the Connect MM Registry, 40% are ineligible for RCTs. This study provides insight into potential modifications of standard eligibility criteria that can lead to improved RCT design and accelerated enrollment.

Infection risk with immunomodulatory and proteasome inhibitor-based therapies across treatment phases for multiple myeloma: A systematic review and meta-analysis

BACKGROUND

The objective of this review was to determine the impact of immunomodulatory drugs (IMiDs) and proteasome inhibitor (PI)-based therapy on infection risk in patients with myeloma across three treatment periods: induction, maintenance therapy and relapse/refractory disease (RRMM).

METHODS

A systematic review and meta-analysis of randomised controlled trials (RCT) of IMiD and PI-based therapy versus conventional therapy from 1990 to 2015 using MEDLINE, EMBASE and CENTRAL was conducted. Study methods, characteristics, interventions, outcomes and rate of infection were extracted using a standardised tool.

FINDINGS

Thirty RCTs of 13,105 patients fulfilled inclusion criteria. The rate of severe infection with the use of IMiD-based therapy was 13.4%, 22.4%, 10.5% and 16.6% for induction therapy for non-transplant- and transplant-eligible patients, maintenance therapy and therapy for RRMM, respectively. Rate of severe infection with PI-based induction in transplant-eligible patients was 19.7%. Compared to conventional therapy, use of IMiD-based induction therapy was associated with reduced risk for transplant patients (RR 0.76, p < 0.01). There was no significant difference with PI-based therapy. For maintenance therapy and RRMM, use of IMiD-based therapy was significantly associated with 74% and 51% increased risk of severe infection, respectively. Compared to thalidomide, bortezomib-based induction therapy and lenalidomide maintenance therapy were associated with increased risk of severe infection (RR 2.03, p < 0.01; RR 1.95, p = 0.03).

INTERPRETATION

The differential impact of myeloma therapies on risk for infection and the effect of treatment phases upon risk have now been established. Thalidomide is associated with the lowest risk of severe infection when used for induction and maintenance therapy.

FUNDING

Fight Cancer Foundation.

Thalidomide treatment for patients with previously untreated multiple myeloma: a meta-analysis of randomized controlled trials

The efficacy and safety of thalidomide as an initial treatment in myeloma patients who were unsuitable for autologous stem cell transplantation (ASCT), as induction treatment prior to ASCT, or as a maintenance treatment was unclear. The purpose of this study was to assess the benefits and risks of thalidomide for previously untreated myeloma patients. MEDLINE, EMBASE, and Cochrane Library were searched for randomized controlled trials (RCTs) of thalidomide used in either induction or maintenance therapy for previously untreated myeloma patients. Twenty-two RCTs enrolling 9098 patients were identified, including 15 RCTs of induction thalidomide, 6 RCTs of maintenance thalidomide, and 1 RCT of induction and maintenance thalidomide. Induction thalidomide improved overall response rate (ORR) (risk ratio (RR) 1.54, 95 % confidence interval (CI) 1.30-1.83), complete response rate (CRR) (RR 3.03, 95 % CI 1.91-4.80), progression-free survival (PFS) (hazard ratio (HR) 0.65, 95 % CI 0.56-0.76), and overall survival (OS) (HR 0.78, 95 % CI 0.67-0.91) in patients who were not allowed to receive ASCT. Induction thalidomide improved pre-ASCT ORR (RR 1.20, 95 % CI 1.11-1.30), pre-ASCT and post-ASCT CRR (RR 1.47, 95 % CI 1.12-1.93 and RR 1.23, 95 % CI 1.00-1.50, respectively), and PFS (HR 0.73, 95 % CI 0.59-0.91) in patients who were allowed to receive ASCT, but it did not improve post-ASCT ORR (RR 1.04, 95 % CI 0.99-1.09) and OS (HR 0.91, 95 % CI 0.79-1.05). Improved PFS and prolonged OS were observed (HR 0.61, 95 % CI 0.53-0.70 and HR 0.77, 95 % CI 0.62-0.95, respectively) when thalidomide was added to maintenance therapy. More patients experienced venous thromboembolism (VTE) of grade 3/4 when thalidomide was added to induction or maintenance therapy (HR 2.15, 95 % CI 1.58-2.92 and RR 1.96, 95 % CI 1.13-3.40, respectively). Induction thalidomide still increased the risk of VTE (RR 1.53, 95 % CI 1.12-2.08) after VTE prophylaxis was used. Induction thalidomide effectively improved CRR, ORR, and PFS (except post-ASCT ORR). Notably, induction thalidomide improved OS in patients who were not allowed to receive ASCT but not in patients who were allowed to receive ASCT. The addition of thalidomide to maintenance therapy improved both PFS and OS. However, thalidomide led to a greater risk of VTE with grade 3/4. This risk did not disappear after VTE prophylaxis was used in induction therapy with thalidomide.

Infectious complications in patients with newly diagnosed multiple myeloma: A complication from the past?

Infectious complications are an important risk factor for early mortality in patients with multiple myeloma. However, data about the impact and severity of infections in these patients in the era of new therapies have not been properly analyzed. This review has reviewed the incidence and severity of infections complications and infection-related mortality during induction treatment in patients with newly diagnosed myeloma receiving regimens with new drugs within randomized trials. The results show that infections are still a major cause of morbidity, especially among elderly patients receiving immunomodulatory drugs seen in up to 28% of patients in some trials vs less than 10% among transplant-eligible patients. Overall infection-related mortality ranged from 0-7% in transplant-ineligible patients, with no infection-related deaths in the majority of the trials including younger patients. Strategies directed to further reduce these complications and a better knowledge of their impact in patients treated outside clinical trials are needed.

Mechanisms of Drug Resistance in Relapse and Refractory Multiple Myeloma

Multiple myeloma (MM) is a hematological malignancy that remains incurable because most patients eventually relapse or become refractory to current treatments. Although the treatments have improved, the major problem in MM is resistance to therapy. Clonal evolution of MM cells and bone marrow microenvironment changes contribute to drug resistance. Some mechanisms affect both MM cells and microenvironment, including the up- and downregulation of microRNAs and programmed death factor 1 (PD-1)/PD-L1 interaction. Here, we review the pathogenesis of MM cells and bone marrow microenvironment and highlight possible drug resistance mechanisms. We also review a potential molecular targeting treatment and immunotherapy for patients with refractory or relapse MM.

Inhibition of CRM1-dependent nuclear export sensitizes malignant cells to cytotoxic and targeted agents

Nuclear-cytoplasmic trafficking of proteins is a significant factor in the development of cancer and drug resistance. Subcellular localization of exported proteins linked to cancer development include those involved in cell growth and proliferation, apoptosis, cell cycle regulation, transformation, angiogenesis, cell adhesion, invasion, and metastasis. Here, we examined the basic mechanisms involved in the export of proteins from the nucleus to the cytoplasm. All proteins over 40kDa use the nuclear pore complex to gain entry or exit from the nucleus, with the primary nuclear export molecule involved in these processes being chromosome region maintenance 1 (CRM1, exportin 1 or XPO1). Proteins exported from the nucleus must possess a hydrophobic nuclear export signal (NES) peptide that binds to a hydrophobic groove containing an active-site Cys528 in the CRM1 protein. CRM1 inhibitors function largely by covalent modification of the active site Cys528 and prevent binding to the cargo protein NES. In the absence of a CRM1 inhibitor, CRM1 binds cooperatively to the NES of the cargo protein and RanGTP, forming a trimer that is actively transported out of the nucleus by facilitated diffusion. Nuclear export can be blocked by CRM1 inhibitors, NES peptide inhibitors or by preventing post-translational modification of cargo proteins. Clinical trials using the classic CRM1 inhibitor leptomycin B proved too toxic for patients; however, a new generation of less toxic small molecule inhibitors is being used in clinical trials in patients with both hematological malignancies and solid tumors. Additional trials are being initiated using small-molecule CRM1 inhibitors in combination with chemotherapeutics such as pegylated liposomal doxorubicin. In this review, we present evidence that combining the new CRM1 inhibitors with other classes of therapeutics may prove effective in the treatment of cancer. Potential combinatorial therapies discussed include the use of CRM1 inhibitors and the addition of alkylating agents (melphalan), anthracyclines (doxorubicin and daunomycin), BRAF inhibitors, platinum drugs (cisplatin and oxaliplatin), proteosome inhibitors (bortezomib and carfilzomib), or tyrosine-kinase inhibitors (imatinib). Also, the sequence of treatment may be important for combination therapy. We found that the most effective treatment regimen involved first priming the cancer cells with the CRM1 inhibitor followed by doxorubicin, bortezomib, carfilzomib, or melphalan. This order sensitized both de novo and acquired drug-resistant cancer cell lines.

Role of thalidomide in the treatment of patients with multiple myeloma

The first of the so-called "novel agents" (thalidomide, lenalidomide, and bortezomib), thalidomide has demonstrated activity as a single agent and in combination with other agents in patients with relapsed and/or refractory MM. The combination of melphalan, prednisone, and thalidomide (MPT) has become a standard treatment option for newly diagnosed patients who are ineligible for high-dose chemotherapy with autologous stem cell transplantation (ASCT). For patients intending to undergo ASCT, the combination of thalidomide, dexamethasone and cyclophosphamide can be used as a non-myelosuppressive induction regimen. Treatment with thalidomide is associated with an increased risk of developing peripheral neuropathy, which can be managed with dose reductions and discontinuation, and venous thromboembolism, which warrants thromboprophylaxis. While its adverse event profile may preclude prolonged use as maintenance therapy, thalidomide is an effective and well-tolerated salvage therapy option. Ongoing trials continue to evaluate novel thalidomide-based regimens to further optimize the use of thalidomide in the management of MM.

Multiple myeloma: improved outcomes with new therapeutic approaches

PURPOSE OF REVIEW

Nearly all patients with multiple myeloma will eventually relapse; and, thus, it is critical to identify new treatments that increase therapeutic options for these patients. This review highlights the newest approaches with already approved drugs for treating this common B-cell malignancy.

RECENT FINDINGS

Most patients with multiple myeloma in both the frontline and relapsed/refractory settings are now treated with a combination of dexamethasone with the proteasome inhibitor bortezomib and/or an immunomodulatory agent thalidomide or lenalidomide. However, alkylating agents including melphalan, cyclophosphamide and most recently bendamustine as well as anthracyclines, especially the pegylated liposomal doxorubicin, have shown high response rates and prolonged remissions when combined with these agents. There are emerging data showing the importance of maintenance therapy especially with lenalidomide. Because of the marked improvement in survival of multiple myeloma during the past decade, there has been a renewed emphasis on developing therapies that are not only effective but also well tolerated. Alternative dosing, scheduling and routes of administration of already approved drugs have proven effective in accomplishing these goals.

SUMMARY

The availability of drugs with different mechanisms that produce anti-multiple myeloma effects and also show synergistic effects has paved the way for more effective and safer combinations and led to multiple myeloma patients living longer with improved quality of lives.

Management of treatment-emergent peripheral neuropathy in multiple myeloma

Peripheral neuropathy (PN) is one of the most important complications of multiple myeloma (MM) treatment. PN can be caused by MM itself, either by the effects of the monoclonal protein or in the form of radiculopathy from direct compression, and particularly by certain therapies, including bortezomib, thalidomide, vinca alkaloids and cisplatin. Clinical evaluation has shown that up to 20% of MM patients have PN at diagnosis and as many as 75% may experience treatment-emergent PN during therapy. The incidence, symptoms, reversibility, predisposing factors and etiology of treatment-emergent PN vary among MM therapies, with PN incidence also affected by the dose, schedule and combinations of potentially neurotoxic agents. Effective management of treatment-emergent PN is critical to minimize the incidence and severity of this complication, while maintaining therapeutic efficacy. Herein, the state of knowledge regarding treatment-emergent PN in MM patients and current management practices are outlined, and recommendations regarding optimal strategies for PN management during MM treatment are provided. These strategies include early and regular monitoring with neurological evaluation, with dose modification and treatment discontinuation as indicated. Areas requiring further research include the development of MM-specific, patient-focused assessment tools, pharmacogenomic analysis of patient DNA, and trials to assess the efficacy of pharmacological interventions.

Cyclophosphamide, thalidomide, and dexamethasone as induction therapy for newly diagnosed multiple myeloma patients destined for autologous stem-cell transplantation: MRC Myeloma IX randomized trial results

BACKGROUND

Thalidomide is active in multiple myeloma and is associated with minimal myelosuppression, making it a good candidate for induction therapy prior to high-dose therapy with autologous stem-cell transplantation.

DESIGN AND METHODS

Oral cyclophosphamide, thalidomide, and dexamethasone was compared with infusional cyclophosphamide, vincristine, doxorubicin, and dexamethasone in patients with newly diagnosed multiple myeloma.

RESULTS

The post-induction overall response rate (≥ partial response) for the intent-to-treat population was significantly higher with cyclophosphamide-thalidomide-dexamethasone (n=555) versus cyclophosphamide-vincristine-doxorubicin-dexamethasone (n=556); 82.5% versus 71.2%; odds ratio 1.91; 95% confidence interval 1.44-2.55; P<0.0001. The complete response rates were 13.0% with cyclophosphamide-thalidomide-dexamethasone and 8.1% with cyclophos-phamide-vincristine-doxorubicin-dexamethasone (P=0.0083), with this differential response being maintained in patients who received autologous stem-cell transplantation (post-transplant complete response 50.0% versus 37.2%, respectively; P=0.00052). Cyclophosphamide-thalidomide-dexamethasone was non-inferior to cyclophosphamide-vincristine-doxorubicin-dexamethasone for progression-free and overall survival, and there was a trend toward a late survival benefit with cyclophosphamide-thalidomide-dexamethasone in responders. A trend toward an overall survival advantage for cyclophosphamide-thalidomide-dexamethasone over cyclophosphamide-vincristine-doxorubicin-dexamethasone was also observed in a subgroup of patients with favorable interphase fluorescence in situ hybridization. Compared with cyclophosphamide-vincristine-doxorubicin-dexamethasone, cyclophosphamide-thalidomide-dexamethasone was associated with more constipation and somnolence, but a lower incidence of cytopenias.

CONCLUSIONS

The cyclophosphamide-thalidomide-dexamethasone regimen showed improved response rates and was not inferior in terms of survival outcomes to the standard infusional regimen of cyclophosphamide-vincristine-doxorubicin-dexamethasone. Based on its oral administration and the reduced incidence of infection and cytopenia, cyclophosphamide-thalidomide-dexa-methasone may be considered an effective induction therapy option for patients with newly diagnosed multiple myeloma. (ISRCTN: 68454111).

Postrelapse survival rate correlates with first-line treatment strategy with thalidomide in patients with newly diagnosed multiple myeloma: a meta-analysis

To define whether or not thalidomide exposure upfront to newly diagnosed patients with multiple myeloma would adversely impact postrelapse survival (PRS), we performed a meta-analysis of randomized controlled trials. Medline, Embase, the Cochrane controlled trials register and the Science Citation Index were searched. Thirteen trials were identified, covering a total of 6097 subjects, and PRS data were available from eight trials. The summary hazard ratio (thalidomide vs control) of all those trials for PRS was 1.23 [95% CI, 1.05-1.45]. The HRs of thalidomide maintenance subgroups were 0.90 [0.57-1.41] for PRS, 0.61 [0.44-0.83] for progression-free survival (PFS) and 0.54 [0.36-0.80] for overall survival, respectively. The corresponding ratios of thalidomide induction and maintenance subgroups were 1.41 [1.13-1.76] for PRS, 0.68 [0.59-0.79] for PFS and 0.87 [0.73-1.04] for overall survival, respectively. In conclusion, thalidomide exposed upfront correlated with shorter PRS that partially compensated for prolonged initially PFS and resulted in no survival benefit when it is given as both induction pre-autologous and maintenance post-autologous stem cell transplantation; shorter PRS was not observed, and survival was improved when it is given only during maintenance phase following autologous stem cell transplantation in the patients with myeloma and who are eligible for transplant.

The role of maintenance thalidomide therapy in multiple myeloma: MRC Myeloma IX results and meta-analysis

Thalidomide maintenance has the potential to modulate residual multiple myeloma (MM) after an initial response. This trial compared the effect of thalidomide maintenance and no maintenance on progression-free survival (PFS) and overall survival (OS) in MM patients. After intensive or nonintensive induction therapy, 820 newly diagnosed MM patients were randomized to open-label thalidomide maintenance until progression, or no maintenance. Interphase FISH (iFISH) analysis was performed at study entry. Median PFS was significantly longer with thalidomide maintenance (log-rank P < .001). Median OS was similar between regimens (log-rank P = .40). Patients with favorable iFISH showed improved PFS (P = .004) and a trend toward a late survival benefit. Patients with adverse iFISH receiving thalidomide showed no significant PFS benefit and worse OS (P = .009). Effective relapse therapy enhanced survival after progression, translating into a significant OS benefit. Meta-analysis of this and other studies show a significant late OS benefit (P < .001, 7-year difference hazard ratio = 12.3; 95% confidence interval, 5.5-19.0). Thalidomide maintenance significantly improves PFS and can be associated with improved OS. iFISH testing is important in assessing the clinical impact of maintenance therapy. Overview analysis demonstrated that thalidomide maintenance was associated with a significant late OS benefit. This trial was registered at www.isrctn.org as #ISRCTN68454111.

Evolving role of high dose stem cell therapy in multiple myeloma

Conventional chemotherapy has been used in the treatment of multiple myeloma. However the development of autologous stem cell transplant represented a major advance in its therapy. Complete response (CR) rates to the tune of 40-45% were seen and this translated into improvements in progression-free survival and also overall survival in some studies. As a result the autologous stem cell transplants (ASCT) is the standard of care in eligible patients and can be carried out with low treatment-related mortality. Allogenic transplant carries the potential for cure but the high mortality associated with the myeloablative transplant has made it unpopular. Reduced Intensity Stem Cell Transplants (RIST) have been tried with varying success but with a high degree of morbidity as compared to the ASCT. Introduction of newer agents like thalidomide, lenalidomide, bortezomib and liposomal doxorubicin into the induction regimens has resulted in higher CR and very good partial response rates (VGPR) as well as improvement in ease of administration. These drugs have also proved useful in patients with adverse cytogenetics. Recent trials suggest that this has translated into improvements in response rates post-ASCT. There is a suggestion that patients achieving CR/nCR or VGPR after induction therapy should be placed on maintenance and ASCT then could be used as a treatment strategy at relapse. All these trends however await confirmation from further trials. Tandem transplants have been used to augment the results obtained with ASCT and have demonstrated their utility in patients who achieved only a partial response or stable disease in response to the first transplant as well as patients with adverse cytogenetics. Incorporation of bortezomib along with melphalan into the conditioning regimen has also been tried. RIST following ASCT has been tried with varying success but does not offer any major advantage over ASCT and is associated with higher morbidity. It is hoped that recent advances in therapy will contribute greatly to improved survival.

Advances in the treatment of monoclonal gammopaties: The emerging role of targeted therapy in plasma cell dyscrasias

The paradigm for the treatment of monoclonal gammopaties has dramatically changed: therapeutic options in multiple myeloma (MM) have evolved from the introduction of melphalan and prednisone in the 1960s, high-dose chemotherapy and stem cell transplantation in the late 1980s and 1990s, to the rapid introduction of small novel molecules within the last seven years. Based on the understanding of the complex interaction of the MM cells with the bone marrow microenvironment and the signaling pathways that are dysregulated in this process, a number of novel therapeutic agents are now available. Specifically, three novel agents with a specific-targeted anti-MM activity, have been FDA-approved for the treatment of this disease, namely Bortezomib, thalidomide, and lenalidomide which are now all playing a key role in the treatment of MM. The success of targeted therapy in MM has since led to the development and investigation of more than 30 new compounds in this disease and in other plasma cell dyscrasias such as Waldenström’s macroglobulinemia and primary amyloidosis, both in the preclinical settings and as part of clinical trials.

The role of bortezomib, thalidomide and lenalidomide in the management of multiple myeloma: an overview of clinical and economic information

Bortezomib, thalidomide and lenalidomide can be aimed at treating patients with newly diagnosed multiple myeloma (both eligible and ineligible for transplantation) as well as those with relapsed or refractory disease. This review analysed the available clinical and economic data on these three drugs. Irrespective of which of the three agents is considered, the magnitude of the benefit in newly diagnosed cases (transplanted or non-transplanted) tends to be between 10 and 20 months per patient in terms of progression-free survival or survival; the survival benefit is smaller in relapsed or refractory disease. In addition, a single-institution observational analysis evaluated the outcomes in nearly 3000 consecutive patients examined between 1971 and 2006. The survival in patients diagnosed between 2001 and 2006 was longer than that observed in patients diagnosed between 1994 and 2000. This finding supports the conclusion that novel agents provide a survival improvement compared with traditional therapy. Formal cost-effectiveness studies on these three agents are still lacking. A MEDLINE search retrieved only four short papers or letters and no full-length analysis. Hence, the cost effectiveness of these agents needs further investigation, with separate assessments of the different therapeutic settings. In a simplified analysis, we tried to contrast the average cost of treatment for each of the novel agents versus their respective benefit, expressed in quality-adjusted survival. Despite its preliminary nature, our assessment indicates that the cost effectiveness of these three agents is likely to be within commonly accepted pharmacoeconomic thresholds.

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

INTRODUCTION

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

PURPOSE

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

RESULTS

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

CONCLUSION

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

Outcome and toxicity in the modern era of new drugs for multiple myeloma: a reappraisal for comparison with future investigational trials

The introduction of new drugs such as thalidomide, lenalidomide, and bortezomib has led to novel treatment strategies and significantly improved the outcome of patients with multiple myeloma (MM). The enhanced knowledge of myeloma pathogenesis has allowed the identification of new therapeutic targets and many clinical trials are either planned or in progress to evaluate these more selective drugs in the near future. The results of these studies, however, will have to be compared with the results of existing novel therapies for the treatment of MM in order to define whether new protocols do not duplicate current new standards and constitute a real improvement. We reviewed the results of a series of phase I, II, III studies with thalidomide, lenalidomide, and bortezomib combinations for newly diagnosed MM in order to define a reasonable standard in terms of activity, efficacy, and toxicity and to have a potentially useful starting point for comparisons with future investigational trials. Three-drug regimens appear to double the complete remission (CR) rate (20%), though regimens containing 4 drugs triple the CR rate (30%), compared with those containing only 2 agents (10%). These improvements in the depth and quality of response translate into a progressive increase in the progression-free survival rate at 2 years (from approximately 54%-62% to 75%, respectively). Conversely, by using additional agents, a marked increase in hematologic toxicity has been described (8%, 28%, and 28% respectively), whereas nonhematologic toxicity appears to be similar (26%, 24%, and 27%, respectively). These results suggest that new trials in the future will constitute significant progress if they can improve on the current relatively favorable efficacy/toxicity ratio. Nonetheless, exciting new combinations in development do hold promise and results from these studies are eagerly awaited.

Infectious complications in patients with multiple myeloma treated with new drug combinations containing thalidomide

The literature provides scant data concerning infectious complications and their effect on the outcome of patients with multiple myeloma (MM) treated with new drug combinations. Despite no substantial myelotoxic effect, thalidomide increases the risk of severe infections in patients with MM. We studied 202 patients who received regimens containing thalidomide in order to assess the time, type, outcome, and factors affecting development of severe infections, role of antibiotic prophylaxis, and effect of severe infections on final outcome. Thirty-eight patients (19%) developed a severe infection early during induction therapy and most infections were pneumonia. Only one patient died due to septic shock during neutropenia. No significant differences were reported in terms of progression-free survival (PFS) and overall survival (OS) between patients developing a severe infection and those who did not. Multivariate analysis determined a monoclonal component >3 g/dL and platelets <130 ,000/μL as factors associated with increased risk of severe infection. Primary antibiotic prophylaxis significantly decreased the probability of severe infection only in patients having both the above risk factors. Patients with MM receiving thalidomide combinations with high tumor burden are at high risk of developing severe infections and require primary antibiotic prophylaxis, whereas in other patients it is questionable. However, patient final outcome was not affected by infection development.

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.

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.

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.

Emerging therapies for multiple myeloma

Multiple myeloma (MM) is a clonal plasma cell malignancy clinically characterized by osteolytic lesions, immunodeficiency, and renal disease. There are an estimated 750,000 people diagnosed with MM worldwide, with a median overall survival of 3 - 5 years. Besides chromosomal aberrations, translocations, and mutations in essential growth and tumor-suppressor genes, accumulating data strongly highlight the pathophysiologic role of the bone marrow (BM) microenvironment in MM pathogenesis. Based on this knowledge, several novel agents have been identified, and treatment options in MM have fundamentally changed during the last decade. Thalidomide, bortezomib, and lenalidomide have been incorporated into conventional cytotoxic and transplantation regimens, first in relapsed and refractory and now also in newly diagnosed MM. Despite these significant advances, there remains an urgent need for more efficacious and tolerable drugs. Indeed, a plethora of preclinical agents awaits translation from the bench to the bedside. This article reviews the scientific rationale of new therapy regimens and newly identified therapeutic agents - small molecules as well as therapeutic antibodies - that hold promise to further improve outcome in MM.

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.

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.

Thalidomide in multiple myeloma--clinical trials and aspects of drug metabolism and toxicity

BACKGROUND

After the tragic events in the early 1960s, thalidomide has re-emerged as therapeutic for multiple myeloma (MM). It was first approved for the treatment of erythema nodosum leprosum, and is now under evaluation for hematologic and non-hematologic disorders. Its complex mechanism of action is not fully understood; however extensive preclinical studies in MM have revealed its antiangiogenic and immunomodulatory properties.

OBJECTIVE

In this review, we focus on the importance and toxicity of thalidomide in today's clinical use.

METHODS

Key preclinical and clinical trials available as well as data on the pharmacokinetics and pharmacodynamics of thalidomide in humans are summarized.

CONCLUSIONS

Thalidomide is widely used as first-line treatment and in relapsed/refractory MM. The most common side effects are fatigue, constipation and peripheral neuropathy, and careful monitoring is required to avoid fetal exposure.

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.

Non-thromboembolic pulmonary hypertension in multiple myeloma, after thalidomide treatment: a pilot study

BACKGROUND

Multiple myeloma (MM) is thrombogenic as a consequence of multiple hemostatic effects and endothelial damage. Thalidomide has been associated with an increased risk of thromboembolic pulmonary hypertension (PH). PH in the absence of venous thromboembolism has also been described in MM patients during thalidomide treatment.

AIM

Detection of clinical and subclinical nonthromboembolic PH in MM patients after thalidomide treatment.

PATIENTS AND METHODS

Eighty-two patients, 46-82 years (median age 61 years), 42 males, were studied. They underwent echocardiographic study at baseline, 1 month thereafter, 6 months later and whenever symptoms indicating deterioration of cardiac function appeared. Echocardiographic signs of PH were especially identified.

RESULTS

Clinical and echocardiographic evaluation revealed four patients (out of 82 patients, 4.87%) with PH. Nonimaging and imaging diagnostic methods excluded thromboembolic PH. Statistical analysis demonstrated significant correlation between structural heart disease and PH (r = 14.078; P = 0.008). No significant correlation between age (r = 0.770; P = 0.724), gender (r = 1.157; P = 0.285), International Staging System (ISS) (r = 0.316; P = 0.716) and PH was found.

CONCLUSIONS

Preexisted endothelial dysfunction due to structural cardiac disease enhances the vasoactive substances release causing increased pulmonary vascular resistance. Thalidomide possibly causes a vasodilator and vasoconstriction imbalance, which may cause abnormal pulmonary vascular response interfering to a vicious circle perpetuating PH.

Thalidomide for treatment of multiple myeloma: 10 years later

Thalidomide, bortezomib, and lenalidomide have recently changed the treatment paradigm of myeloma. In young, newly diagnosed patients, the combination of thalidomide and dexamethasone has been widely used as induction treatment before autologous stem cell transplantation (ASCT). In 2 randomized studies, consolidation or maintenance with low-dose thalidomide has extended both progression-free and overall survival in patients who underwent ASCT at diagnosis. In elderly, newly diagnosed patients, 3 independent randomized studies have reported that the oral combination of melphalan and prednisone plus thalidomide (MPT) is better than the standard melphalan and prednisone (MP). These studies have shown better progression-free survival, and 2 have shown improved overall survival for patients assigned to MPT. In refractory-relapsed disease, combinations including thalidomide with dexamethasone, melphalan, doxorubicin, or cyclophosphamide have been extensively investigated. The risks of side effects are greater when thalidomide is used in combination with other drugs. Thromboembolism and peripheral neuropathy are the major concern. The introduction of anticoagulant prophylaxis has reduced the rate of thromboembolism to less than 10%. Immediate thalidomide dose reduction or discontinuation when paresthesia is complicated by pain or motor deficit has decreased the severity of neuropathy. Future studies will define the most effective or the best sequence of combinations which could improve life expectancy.

Current status of antivascular therapy and targeted treatment in the clinic

Antivascular and targeted therapy are now an integrated part of the treatment of myelogenous leukemias, GIST tumours, B-cell lymphomas and breast cancer. In various malignancies improved responses and prolongation of survival for several months is regularly reported. The progress in this field is relevant for hyperthermia. Heat has among other effects documented antivascular effects, and can be considered as one of the established methods in the field based on several randomised phase III studies. Hyperthermia should be considered for combination with other antiangiogenic agents.

High-dose chemotherapy and autologous hematopoietic stem cell transplantation in myeloma patients under the age of 65 years

One or two cycles of high-dose chemotherapy with autologous hematopoietic stem cell transplantation have been shown to improve response rates and survival in myeloma. While this observation has largely been made in patients under the age of 65 years, there is evidence to suggest that the conclusions can be extrapolated to older individuals as well. In contrast to other hematologic malignancies treated with high-dose therapy, autografted myeloma patients continue to relapse several years after transplantation, and few patients are cured with this modality. However, up to a third of patients may be alive beyond a decade; some with excellent quality of life giving rise to the concept of 'operational cure'. Relapsing disease can be treated with novel agents or repeat high-dose chemotherapy and transplantation. The pressing questions to which answers are not obvious at the moment are whether tandem transplantation should be offered to all patients, and whether novel agents should be used before transplantation or reserved for relapse. Despite their excellent activity, there is no evidence so far that novel agents such as thalidomide, bortezomib and lenalidomide can replace high-dose chemotherapy and stem cell transplantation.