Risk factors for, and reversibility of, peripheral neuropathy associated with bortezomib-melphalan-prednisone in newly diagnosed patients with multiple myeloma: subanalysis of the phase 3 VISTA study

How I manage the toxicities of myeloma drugs

The treatment of multiple myeloma is considered a continuously evolving paradigm as a result of the growing availability of new and highly effective drugs, including first- and second-generation proteasome inhibitors, immunomodulatory agents, and monoclonal antibodies. Clinical trials advocate long-term rather than short-term treatment schedules with combinations of these new anti-myeloma drug classes. Although the overall toxicity profile of the recommended regimens can be considered favorable, their increasing complexity and prolonged use warrant a heightened vigilance for early and late side effects, a priori because real-life patients can be more frail or present with 1 or more comorbidities. The treatment decision process, at diagnosis and at relapse, therefore requires myeloma physicians to carefully balance efficacy and toxicity profiles for each individual patient. Early and/or unnecessary tapering or treatment discontinuation for drug-related adverse events may not only reduce patients' quality of life, but also negatively impact their outcome. Accurate knowledge in recognizing and managing the potential side effects of present-day treatment regimens is therefore a cornerstone in myeloma care. Using 5 case vignettes, we discuss how to prevent and manage the most common nonhematological adverse events of anti-myeloma treatment regimens containing proteasome inhibitors, immunomodulatory drugs, and monoclonal antibodies.

Long-Term Effects, Pathophysiological Mechanisms, and Risk Factors of Chemotherapy-Induced Peripheral Neuropathies: A Comprehensive Literature Review

Neurotoxic anticancer drugs, such as platinum-based anticancer drugs, taxanes, vinca alkaloids, and proteasome/angiogenesis inhibitors are responsible for chemotherapy-induced peripheral neuropathy (CIPN). The health consequences of CIPN remain worrying as it is associated with several comorbidities and affects a specific population of patients already impacted by cancer, a strong driver for declines in older adults. The purpose of this review is to present a comprehensive overview of the long-term effects of CIPN in cancer patients and survivors. Pathophysiological mechanisms and risk factors are also presented. Neurotoxic mechanisms leading to CIPNs are not yet fully understood but involve neuronopathy and/or axonopathy, mainly associated with DNA damage, oxidative stress, mitochondria toxicity, and ion channel remodeling in the neurons of the peripheral nervous system. Classical symptoms of CIPNs are peripheral neuropathy with a “stocking and glove” distribution characterized by sensory loss, paresthesia, dysesthesia and numbness, sometimes associated with neuropathic pain in the most serious cases. Several risk factors can promote CIPN as a function of the anticancer drug considered, such as cumulative dose, treatment duration, history of neuropathy, combination of therapies and genetic polymorphisms. CIPNs are frequent in cancer patients with an overall incidence of approximately 38% (possibly up to 90% of patients treated with oxaliplatin). Finally, the long-term reversibility of these CIPNs remain questionable, notably in the case of platinum-based anticancer drugs and taxanes, for which CIPN may last several years after the end of anticancer chemotherapies. These long-term effects are associated with comorbidities such as depression, insomnia, falls and decreases of health-related quality of life in cancer patients and survivors. However, it is noteworthy that these long-term effects remain poorly studied, and only limited data are available such as in the case of bortezomib and thalidomide-induced peripheral neuropathy.

The magnitude of neurotoxicity in patients with multiple myeloma and the impact of dose modifications: results from the population-based PROFILES registry

The aim of this analysis is to assess (1) self-reported chemotherapy-induced peripheral neuropathy (CIPN) symptoms; (2) its association with sociodemographic and clinical characteristics; and (3) treatment dose modifications and its influence on the magnitude of neurotoxicity in a population-based cohort of patients with multiple myeloma (MM). MM patients (n = 156), diagnosed between 2000 and 2014, filled out the EORTC QLQ-CIPN20 (65% response). Data on treatment, outcomes, and dose modifications were extracted from the medical files. Fifty-three percent of patients reported at least one and on average three neuropathy symptoms that bothered them the most during the past week, with tingling toes/feet as most reported. In multivariate analysis, thalidomide, especially higher cumulative dose, was associated with neuropathy (β = 0.26, CI 95% 0.27-15.34, p = 0.04) and CIPN was not associated with age, sex, time since last course of therapy, number of prior therapies, osteoarthritis, or diabetes. Dose modifications were often applied (65%). Although not statistically significant, a trend towards higher sensory (22 vs. 15 vs. 12, p = 0.22) and motor neuropathy scores (21 vs. 15 vs. 11, p = 0.36) was observed among patients receiving dose modification because of CIPN (31%) compared to those receiving a dose modification for another reason or no dose modification, without altering treatment response. CIPN is a common dose limiting side effect in patients with MM. Severity of CIPN was mainly affected by treatment with thalidomide. In spite of dose modifications, patients still reported somewhat higher neuropathy scores without altered response rates. Early dose modification based on a more reliable tool for CIPN measurements may prove value.

Prediction of peripheral neuropathy in multiple myeloma patients receiving bortezomib and thalidomide: a genetic study based on a single nucleotide polymorphism array

Bortezomib- and thalidomide-based therapies have significantly contributed to improved survival of multiple myeloma (MM) patients. However, treatment-induced peripheral neuropathy (TiPN) is a common adverse event associated with them. Risk factors for TiPN in MM patients include advanced age, prior neuropathy, and other drugs, but there are conflicting results about the role of genetics in predicting the risk of TiPN. Thus, we carried out a genome-wide association study based on more than 300 000 exome single nucleotide polymorphisms in 172 MM patients receiving therapy involving bortezomib and thalidomide. We compared patients developing and not developing TiPN under similar treatment conditions (GEM05MAS65, NCT00443235). The highest-ranking single nucleotide polymorphism was rs45443101, located in the PLCG2 gene, but no significant differences were found after multiple comparison correction (adjusted P = .1708). Prediction analyses, cytoband enrichment, and pathway analyses were also performed, but none yielded any significant findings. A copy number approach was also explored, but this gave no significant results either. In summary, our study did not find a consistent genetic component associated with TiPN under bortezomib and thalidomide therapies that could be used for prediction, which makes clinical judgment essential in the practical management of MM treatment.

Predictive Value of Glycated Hemoglobin and Body Mass Index for Pretreatment Neuropathy in Patients With Multiple Myeloma

BACKGROUND

Peripheral neuropathy (PN) is detected in up to 62% patients with multiple myeloma (MM) at diagnosis. No specific risk factor for pretreatment neuropathy has been identified.

PATIENTS AND METHODS

We evaluated 29 sequential patients with MM attending our tertiary care center for peripheral neuropathy at diagnosis using symptoms, clinical examination, and nerve conduction studies (NCSs). Total Neuropathy Score, reduced (TNSr) and Total Neuropathy Score, clinical (TNSc) were calculated, and a score of ≥ 2 in each scale was considered diagnostic of PN. The study was approved by our institutional review board.

RESULTS

We found that 51.7% (n = 15) and 17.2% (n = 5) of patients had pretreatment neuropathy by TNSr and TNSc scales, respectively. Higher glycated hemoglobin (HbA1C) (P = .022), higher body mass index (BMI) (P = .008), higher serum creatinine levels (P = .023), and higher blood urea levels (P = .006) were associated with neuropathy by TNSr in univariate analysis. Higher blood urea levels (P = .023), higher serum creatinine levels (P = .003), and higher serum β2-microglobulin levels (P = .013) were associated with neuropathy by TNSc in univariate analysis. Higher HbA1c levels (P = .036; odds ratio [OR], 9.46) and BMI (P = .028; OR, 1.78) were associated with neuropathy by TNSr on binomial logistic regression analysis. Cutoffs of 5.6% (sensitivity, 60%; specificity, 71.4%) and 23.7 kg/m(2) (sensitivity, 80%; specificity, 71.4%) were obtained for HbA1c (area under the curve [AUC], 0.75) and BMI (AUC, 0.79), respectively, on receiver operating characteristic (ROC) curve analysis to predict neuropathy. The combination of HbA1c ≥ 5.6% and BMI ≥ 23.7 kg/m(2) had higher odds of neuropathy by TNSr (OR, 27.0; 95% confidence interval [CI], 2.0-368.4) when compared with either factor alone.

CONCLUSION

Use of TNSr, which incorporates electrophysiological abnormalities in addition to clinical manifestations, improves the detection rate of neuropathy. We found that high HbA1c and high BMI together are risk factors for neuropathy at diagnosis in patients with MM.

Effect of Vitamin E on Oxaliplatin-induced Peripheral Neuropathy Prevention: A Randomized Controlled Trial

BACKGROUND

Peripheral neuropathy is one of the most important limitations of oxaliplatin base regimen, which is the standard for the treatment of colorectal cancer. Evidence has shown that Vitamin E may be protective in chemotherapy-induced peripheral neuropathy. The aim of this study is to evaluate the effect of Vitamin E administration on prevention of oxaliplatin-induced peripheral neuropathy in patients with colorectal cancer.

METHODS

This was a prospective randomized, controlled clinical trial. Patients with colorectal cancer and scheduled to receive oxaliplatin-based regimens were enrolled in this study. Enrolled patients were randomized into two groups. The first group received Vitamin E at a dose of 400 mg daily and the second group observed, until after the sixth course of the oxaliplatin regimen. For oxaliplatin-induced peripheral neuropathy assessment, we used the symptom experience diary questionnaire that completed at baseline and after the sixth course of chemotherapy. Only patients with a score of zero at baseline were eligible for this study.

RESULTS

Thirty-two patients were randomized to the Vitamin E group and 33 to the control group. There was no difference in the mean peripheral neuropathy score changes (after - before) between two groups, after sixth course of the oxaliplatin base regimen (mean difference [after - before] of Vitamin E group = 6.37 ± 2.85, control group = 6.57 ± 2.94; P = 0.78). Peripheral neuropathy scores were significantly increased after intervention compared with a base line in each group (P < 0.001).

CONCLUSIONS

The results from this current trial demonstrate a lack of benefit for Vitamin E in preventing oxaliplatin-induced peripheral neuropathy.

Guillain Barré Syndrome in a multiple myeloma patient after the first course of bortezomib therapy: A case report

Bortezomib is approved for treating relapsed multiple myeloma (MM) and mantle cell lymphoma, and clinical evidence has shown complete clinical responses in MM patients. Peripheral neuropathy is one of the most common adverse effects of bortezomib. However, rare evidence has shown that bortezomib is associated with Guillain-Barré syndrome (GBS). In the present study, a case of GBS is reported in an MM patient finishing the first course of bortezomib therapy. Based on a bone marrow cell examination revealing 34% plasma cell infiltration and according to the International Staging System, the patient was diagnosed with stage III MM (λ type). Thus, a chemotherapy protocol was performed, which consisted of bortezomib and dexamethasone. However, 5 days after the first cycle, paresthesias of the upper and lower limbs developed. Standard nerve conduction studies revealed marked reduction of the motor conduction velocity of the median nerve bilaterally and of the right ulnar nerve, while sensory conduction was significantly slowed in the majority of the nerves of the upper and lower limbs. However, there was no evidence of demyelination. With this clinical evidence, a diagnosis of GBS was considered. The patient was subsequently treated with high-dose intravenous immunoglobulins (IVIGs; 400 mg/kg/day for 5 days). Following IVIG treatment, the symptoms were largely relieved. This study suggested that GBS may occur when administering bortezomib, and that high-dose IVIGs could treat the symptoms of GBS.

An Overview of Bortezomib-Induced Neurotoxicity

The boronic acid dipeptide bortezomib, able to induce tumor cell death by degradation of key proteins, is the first proteasome inhibitor drug to enter clinical practice. It is employed as first-line treatment in relapsed or resistant multiple myeloma (MM) patients. However, bortezomib often induces a dose-limiting toxicity in the form of painful sensory neuropathy, which can mainly be reduced by subcutaneous administration or dose modification. In this review we focus on the current understanding of the pathophysiological mechanisms of bortezomib-induced neuropathy to allow further studies in animal models and humans, including analysis of clinical and pharmacogenetic aspects, to optimize the treatment regimens.

Clinical use of proteasome inhibitors in the treatment of multiple myeloma

Multiple myeloma (MM) is an incurable hematological malignancy characterized by the clonal proliferation of neoplastic plasma cells. The use of proteasome inhibitors in the treatment of MM has led to significant improvements in outcomes. This article reviews data on the use of the two approved proteasome inhibitors (bortezomib and carlfilzomib), as well as newer agents under development. Emphasis is placed on the clinical use of proteasome inhibitors, including management of side effects and combination with other agents.

Bortezomib- and thalidomide-induced peripheral neuropathy in multiple myeloma: clinical and molecular analyses of a phase 3 study

A subanalysis of the GIMEMA-MMY-3006 trial was performed to characterize treatment-emergent peripheral neuropathy (PN) in patients randomized to thalidomide-dexamethasone (TD) or bortezomib-TD (VTD) before and after double autologous transplantation (ASCT) for multiple myeloma (MM). A total of 236 patients randomized to VTD and 238 to TD were stratified according to the emergence of grade ≥2 PN. Gene expression profiles (GEP) of CD138+ plasma cells were analyzed in 120 VTD-treated patients. The incidence of grade ≥2 PN was 35% in the VTD arm and 10% in the TD arm (P < 0.001). PN resolved in 88 and 95% of patients in VTD and TD groups, respectively. Rates of complete/near complete response, progression-free and overall survival were not adversely affected by emergence of grade ≥2 PN. Baseline characteristics were not risk factors for PN, while GEP analysis revealed the deregulated expression of genes implicated in cytoskeleton rearrangement, neurogenesis, and axonal guidance. In conclusion, in comparison with TD, incorporation of VTD into ASCT was associated with a higher incidence of PN which, however, was reversible in most of the patients and did not adversely affect their outcomes nor their ability to subsequently receive ASCT. GEP analysis suggests an interaction between myeloma genetic profiles and development of VTD-induced PN.

Understanding biology to tackle the disease: Multiple myeloma from bench to bedside, and back

Multiple myeloma (MM) is a cancer of antibody-producing plasma cells. The pathognomonic laboratory finding is a monoclonal immunoglobulin or free light chain in the serum and/or urine in association with bone marrow infiltration by malignant plasma cells. MM develops from a premalignant condition, monoclonal gammopathy of undetermined significance (MGUS), often via an intermediate stage termed smoldering multiple myeloma (SMM), which differs from active myeloma by the absence of disease-related end-organ damage. Unlike MGUS and SMM, active MM requires therapy. Over the past 6 decades, major advancements in the care of MM patients have occurred, in particular, the introduction of novel agents (ie, proteasome inhibitors, immunomodulatory agents) and the implementation of hematopoietic stem cell transplantation in suitable candidates. The effectiveness and good tolerability of novel agents allowed for their combined use in induction, consolidation, and maintenance therapy, resulting in deeper and more sustained clinical response and extended progression-free and overall survival. Previously a rapidly lethal cancer with few therapeutic options, MM is the hematologic cancer with the most novel US Food and Drug Administration-approved drugs in the past 15 years. These advances have resulted in more frequent long-term remissions, transforming MM into a chronic illness for many patients.

Chemotherapy-induced peripheral neuropathies in hematological malignancies

Recent developments in the treatment of hematological malignancies, especially with the advent of proteasome inhibitors and immunomodulatory drugs in plasma cell dyscrasias, call for an increased collaboration between hematologists and neurologists. This collaboration involves differentiating chemotherapy-induced peripheral neuropathies (CiPN) from disease-related neurologic complications, early recognition of CiPN and treatment of neuropathic pain. Multiple myeloma, Waldenstrom's macroglobulinemia and light-chain amyloidosis frequently present with peripheral neuropathy. In addition, multiple myeloma, non-Hodgkin lymphomas and leukemia's may mimic peripheral neuropathy by compression or invasion of the extra/intradural space. Platinum compounds, vinca alkaloids, proteasome inhibitors and immunomodulatory drugs may all cause CiPN, each with different and often specific clinical characteristics. Early recognition, by identifying the distinct clinical phenotype of CiPN, is of crucial importance to prevent irreversible neurological damage. No recommendations can be given on the use of neuroprotective strategies because of a lack of convincing clinical evidence. Finally, CiPN caused by vinca-alkaloids, proteasome inhibitors and immunomodulatory drugs is often painful and neurologists are best equipped to treat this kind of painful neuropathy.

Incidence, prevalence, and predictors of chemotherapy-induced peripheral neuropathy: A systematic review and meta-analysis

Chemotherapy-induced peripheral neuropathy (CIPN) is a disabling pain condition resulting from chemotherapy for cancer. Severe acute CIPN may require chemotherapy dose reduction or cessation. There is no effective CIPN prevention strategy; treatment of established chronic CIPN is limited, and the prevalence of CIPN is not known. Here we used a systematic review to identify studies reporting the prevalence of CIPN. We searched Embase, Medline, CAB Abstracts, CINAHL, PubMed central, Cochrane Library, and Web of Knowledge for relevant references and used random-effects meta-regression to estimate overall prevalence. We assessed study quality using the CONSORT and STROBE guidelines, and we report findings according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance. We provide a qualitative summary of factors reported to alter the risk of CIPN. We included 31 studies with data from 4179 patients in our analysis. CIPN prevalence was 68.1% (57.7-78.4) when measured in the first month after chemotherapy, 60.0% (36.4-81.6) at 3months and 30.0% (6.4-53.5) at 6months or more. Different chemotherapy drugs were associated with differences in CIPN prevalence, and there was some evidence of publication bias. Genetic risk factors were reported in 4 studies. Clinical risk factors, identified in 4 of 31 studies, included neuropathy at baseline, smoking, abnormal creatinine clearance, and specific sensory changes during chemotherapy. Although CIPN prevalence decreases with time, at 6months 30% of patients continue to suffer from CIPN. Routine CIPN surveillance during post-chemotherapy follow-up is needed. A number of genetic and clinical risk factors were identified that require further study.

Bortezomib in multiple myeloma: systematic review and clinical considerations

We conducted a systematic review to determine the appropriate use of bortezomib alone or in combination with other agents in patients with multiple myeloma (mm). We searched medline, embase, the Cochrane Library, conference proceedings, and the reference lists of included studies. We analyzed randomized controlled trials and systematic reviews if they involved adult mm patients treated with bortezomib and if they reported on survival, disease control, response, quality of life, or adverse effects. Twenty-six unique studies met the inclusion criteria. For patients with previously untreated mm and for candidates for transplantation, we found a statistically significant benefit in time to progression [hazard ratio (hr): 0.48, p < 0.001; and hr: 0.63, p = 0.006, respectively] and a better response with a bortezomib than with a non-bortezomib regimen (p < 0.001). Progression-free survival was longer with bortezomib and thalidomide than with thalidomide alone (p = 0.01). In non-candidates for transplantation, a significant benefit in overall survival was observed with a bortezomib regimen (hr compared with a non-bortezomib regimen: 0.61; p = 0.008), and in transplantation candidates receiving bortezomib, the response rate was improved after induction (p = 0.004) and after a first transplant (p = 0.016). In relapsed or refractory mm, overall survival (p = 0.03), time to progression (hr: 1.82; p = 0.000004), and progression-free survival (hr: 1.69; p = 0.000026) were significantly improved with bortezomib and pegylated liposomal doxorubicin (compared with bortezomib alone), and bortezomib monotherapy was better than dexamethasone alone (hr: 0.77; p = 0.027). Bortezomib combined with thalidomide and dexamethasone was better than either bortezomib monotherapy or thalidomide with dexamethasone (p < 0.001). In previously untreated or in relapsed or refractory mm patients, bortezomib-based therapy has improved disease control and, in some patients, overall survival.

The positive effects of one-hour intravenous administration of bortezomib on peripheral neuropathy in multiple myeloma patients

Bortezomib-induced peripheral neuropathy (BiPN) in multiple myeloma (MM) patients is a common and serious side effect. Currently, it has been reported that subcutaneous (SC) administration of bortezomib decreases the incidence of BiPN as compared to standard intravenous (IV) bolus injection without any differences in efficacy. However, there are reports of severe injection site reaction following SC administration of bortezomib. The aim of this study was to evaluate the response rate and incidence of BiPN following one-hour IV infusion of bortezomib. The data was retrospectively collected from MM patients who had been treated with IV administration of bortezomib for one hour. Twenty-three patients were evaluated (median age 72 years, 13 males). The median number of treatment cycles was 5 (range 2-10). The cumulative bortezomib dose was 26.0 mg/m(2) (14.3-66.3) and percent of actual per expected cumulative dose was 90% (50-100). The overall response (complete response plus partial response) rate was 65%. The incidence of BiPN was 57% (n = 13) and incidence of severe neuropathy was 4% (n = 1). One-hour IV infusion of bortezomib was an effective regimen for MM with reduced incidence of severe BiPN. This route of administration of bortezomib could be an alternative mode of delivery for patients with severe injection site reactions following SC administration.

Meta-analysis of the efficacy and safety of bortezomib re-treatment in patients with multiple myeloma

INTRODUCTION

Bortezomib is administered for a finite course; thus, patients might remain sensitive to bortezomib-based therapy at relapse. We report a meta-analysis of bortezomib-based retreatment in relapsed/refractory myeloma.

PATIENTS AND METHODS

A systematic literature review identified studies of bortezomib-based retreatment in relapsed/refractory myeloma. Proportions of bortezomib-refractory patients and additional prognostic factors were extracted and used in weighted stratified analyses of TTP and OS. Random-effect pooled estimates were calculated for overall response rate (ORR) and rates of common AEs.

RESULTS

Twenty-three studies (n = 1051 patients) were identified. Bortezomib was administered intravenously in all studies. Across studies in which data were available, pooled, weighted average ORR was 39.1% (95% confidence interval, 30.8%-47.4%), and pooled, weighted average median TTP and OS were 7.5 and 16.6 months, respectively. Patients with fewer previous therapies (≤ 4) and relapsed (not refractory) patients achieved higher ORRs, of 43.4% and 57.2%, respectively. Random-effects meta-regression analysis confirmed that relapsed patients were associated with a higher ORR by 28 to 41 percentage points versus refractory patients. In relapsed patients, median TTP and OS were 8.5 and 19.7 months, respectively. Common Grade 3/4 AEs included thrombocytopenia (35%), neutropenia (15%), anemia (14%), pneumonia (10%), and peripheral neuropathy (3%).

CONCLUSION

Based on these findings, bortezomib retreatment is well tolerated and appears efficacious in relapsed patients. In an era of new and emerging treatment options for relapsed and/or refractory myeloma, these data indicate that bortezomib retreatment might be a highly effective option in previously treated patients.

Impact of dose modification on intravenous bortezomib-induced peripheral neuropathy in multiple myeloma patients

PURPOSE

Patients discontinue bortezomib treatment despite good response to the therapy because of bortezomib-induced neuropathy. Early and active dose reduction is recommended for efficacy of treatment. This study evaluates patterns of bortezomib-associated neuropathy and examines the effectiveness of dose modification on symptom management and treatment compliance.

METHODS

This is a retrospective cohort study of multiple myeloma patients who received bortezomib intravenously from 2009 to 2012 at Samsung Medical Center, Seoul, Korea. Peripheral neuropathy was assessed using neurotoxicity subscale of the FACT/GOG-Ntx at daily clinical practice; physicians modified the dosage and schedule of bortezomib treatment. Mixed-effect models were used for evaluating changes of neuropathy symptoms over time. Linear spline models and multivariate logistic regression were used for testing the effectiveness of interventions.

RESULTS

There were 1,060 visits of 55 multiple myeloma patients during the study period. Patients were most likely to have numbness of feet, painful burning in feet, muscle weakness, and the symptoms worsened over time (P < 0.05). For patients who received intervention (n = 32, 58.1 %), neuropathy symptoms were significantly decreased after the intervention (coefficient, -0.1 (95 % confidence interval (CI), -0.8, 0.6)). The intervention group had on average 5.19 (95 % CI, 3.79, 6.59) more bortezomib administrations and was 1.4 times more likely to complete the treatment (odds ratio, 1.40 (95 % CI, 0.31, 6.32)) than the nonintervention group.

CONCLUSION

Close monitoring of peripheral neuropathy in patients receiving bortezomib is a feasible and useful way to manage neuropathy in the real world.

Bortezomib cumulative dose, efficacy, and tolerability with three different bortezomib-melphalan-prednisone regimens in previously untreated myeloma patients ineligible for high-dose therapy

Substantial efficacy has been demonstrated with bortezomib-melphalan-prednisone in phase III studies in transplant-ineligible myeloma patients using various twice-weekly and once-weekly bortezomib dosing schedules. In VISTA, the regimen comprised four 6-week twice-weekly cycles, plus five 6-week once-weekly cycles. In the GIMEMA MM-03-05 study, the bortezomib-melphalan-prednisone regimen was either per VISTA ('GIMEMA twice-weekly'), or comprised nine 5-week once-weekly cycles ('GIMEMA once-weekly'). In the GEM2005MAS65 study, the regimen comprised one 6-week twice-weekly cycle, plus five 5-week once-weekly cycles. We evaluated the cumulative bortezomib dose administered during bortezomib-melphalan-prednisone, as well as efficacy and tolerability, using patient-level study data. Over all bortezomib-melphalan-prednisone cycles (nine in VISTA/GIMEMA; six in GEM2005MAS65), the median cumulative bortezomib dose administered was 38.5, 42.1, 40.3, and 32.9 mg/m(2) in VISTA, GIMEMA twice-weekly, GIMEMA once-weekly, and GEM2005MAS65, respectively, and the respective proportions of planned bortezomib dose actually delivered were 57.0%, 62.3%, 86.1%, and 90.4%. Response rates following bortezomib-melphalan-prednisone were 74-87% and appeared generally similar between studies. Three-year survival rates were 67.9-75.7% across studies. Grade 3/4 peripheral neuropathy rates were 13% in VISTA and 14% in GIMEMA twice-weekly, but were lower at 2% in GIMEMA once-weekly and 7% in GEM2005MAS65. Discontinuations and bortezomib dose reductions due to peripheral neuropathy were reduced in GIMEMA once-weekly versus VISTA and GIMEMA twice-weekly. Exclusive or predominant use of once-weekly bortezomib dosing in GIMEMA once-weekly and GEM2005MAS65 resulted in high efficacy, comparable with that demonstrated in VISTA, and similar cumulative bortezomib dose with reduced toxicity. Trials are registered with ClinicalTrials.gov: VISTA (Identifier:00111319), GIMEMA MM-03-05 (Identifier:01063179), and GEM2005MAS65 (Identifier:00443235).

Proteasome inhibitors in the treatment of multiple myeloma

Proteasome inhibition has been shown to be an effective strategy for the treatment of multiple myeloma, as demonstrated by the clinical activity of the first-in-class agent bortezomib. Recently, the second-generation proteasome inhibitor carfilzomib has been approved in the USA in the relapsed and refractory setting, and several other investigational agents are in clinical development, including MLN9708, marizomib, oprozomib and delanzomib. Here, the authors provide a comprehensive review of the key role of proteasome inhibitors in the myeloma treatment pathway, and highlight the similarities and differences in pharmacology, routes of administration, and efficacy and safety profiles between bortezomib, carfilzomib and investigational agents. The authors also evaluate the potential for further improving myeloma treatment through the ongoing development of novel proteasome inhibitors.

Overview of proteasome inhibitor-based anti-cancer therapies: perspective on bortezomib and second generation proteasome inhibitors versus future generation inhibitors of ubiquitin-proteasome system

Over the past ten years, proteasome inhibition has emerged as an effective therapeutic strategy for treating multiple myeloma (MM) and some lymphomas. In 2003, Bortezomib (BTZ) became the first proteasome inhibitor approved by the U.S. Food and Drug Administration (FDA). BTZ-based therapies have become a staple for the treatment of MM at all stages of the disease. The survival rate of MM patients has improved significantly since clinical introduction of BTZ and other immunomodulatory drugs. However, BTZ has several limitations. Not all patients respond to BTZ based therapies and relapse occurs in many patients who initially responded. Solid tumors, in particular, are often resistant to BTZ. Furthermore, BTZ can induce dose-limiting peripheral neuropathy (PN). The second generation proteasome inhibitor Carfizomib (CFZ; U.S. FDA approved in August 2012) induces responses in a minority of MM patients relapsed from or refractory to BTZ. There is less PN compared to BTZ. Four other second-generation proteasome inhibitors (Ixazomib, Delanzomib, Oprozomib and Marizomib) with different pharmacologic properties and broader anticancer activities, have also shown some clinical activity in bortezomib-resistant cancers. While the mechanism of resistance to bortezomib in human cancers still remains to be fully understood, targeting the immunoproteasome, ubiquitin E3 ligases, the 19S proteasome and deubiquitinases in pre-clinical studies represents possible directions for future generation inhibitors of ubiquitin-proteasome system in the treatment of MM and other cancers.

Chemotherapy-induced peripheral neurotoxicity: a critical analysis

With a 3-fold increase in the number of cancer survivors noted since the 1970s, there are now over 28 million cancer survivors worldwide. Accordingly, there is a heightened awareness of long-term toxicities and the impact on quality of life following treatment in cancer survivors. This review will address the increasing importance and challenge of chemotherapy-induced neurotoxicity, with a focus on neuropathy associated with the treatment of breast cancer, colorectal cancer, testicular cancer, and hematological cancers. An overview of the diagnosis, symptomatology, and pathophysiology of chemotherapy-induced peripheral neuropathy will be provided, with a critical analysis of assessment strategies, neuroprotective approaches, and potential treatments. The review will concentrate on neuropathy associated with taxanes, platinum compounds, vinca alkaloids, thalidomide, and bortezomib, providing clinical information specific to these chemotherapies.

Phytohemagglutinin-induced IL2 mRNA in whole blood can predict bortezomib-induced peripheral neuropathy for multiple myeloma patients

The proteasome inhibitor bortezomib has revolutionized the treatment of multiple myeloma. However, bortezomib-induced peripheral neuropathy (BiPN) is a serious complication that compromises clinical outcome. If patients with a risk of developing BiPN could be predicted, physicians might prefer weekly, reduced-dose, or subcutaneous approaches. To seek biomarkers for BiPN, we conducted a multicenter prospective study using a simple and unique system. Multiple myeloma patients received twice-weekly or weekly 1.3 mg/m(2) bortezomib intravenously, and a 2-ml sample of whole blood was obtained before treatment and 2-3 days and 1-3 weeks after the first dose. Induction of gene expression was then quantified by real-time PCR. Of a total of 64 enrolled patients, 53 patient samples qualified for mRNA analysis. The BiPN grade was associated with phytohemagglutinin-induced IL2, IFNG and TNFSF2, as well as with lipopolysaccharide-induced IL6 levels. More importantly, of the 19 patients showing a 3-fold increase in phytohemagglutinin-induced IL2, 14 did not suffer from BiPN (73.7% prediction), whereas of the 34 patients with a <3-fold increase, 23 experienced BiPN (67.6% prediction). Therefore, we concluded that pretreatment of phytohemagglutinin-induced IL2 mRNA levels in whole blood serve as a promising biomarker for predicting BiPN, and this finding warrants validation in a larger study.

Impact of obesity on cancer survivorship and the potential relevance of race and ethnicity

Evidence that obesity is associated with cancer incidence and mortality is compelling. By contrast, the role of obesity in cancer survival is less well understood. There is inconsistent support for the role of obesity in breast cancer survival, and evidence for other tumor sites is scant. The variability in findings may be due in part to comorbidities associated with obesity itself rather than with cancer, but it is also possible that obesity creates a physiological setting that meaningfully alters cancer treatment efficacy. In addition, the effects of obesity at diagnosis may be distinct from the effects of weight change after diagnosis. Obesity and related comorbid conditions may also increase risk for common adverse treatment effects, including breast cancer-related lymphedema, fatigue, poor health-related quality of life, and worse functional health. Racial and ethnic groups with worse cancer survival outcomes are also the groups for whom obesity and related comorbidities are more prevalent, but findings from the few studies that have addressed these complexities are inconsistent. We outline a broad theoretical framework for future research to clarify the specifics of the biological-social-environmental feedback loop for the combined and independent contributions of race, comorbid conditions, and obesity on cancer survival and adverse treatment effects. If upstream issues related to comorbidities, race, and ethnicity partly explain the purported link between obesity and cancer survival outcomes, these factors should be among those on which interventions are focused to reduce the burden of cancer.

The protective effects of lafutidine for bortezomib induced peripheral neuropathy

Peripheral neuropathy (PN) caused by bortezomib is an important complication of multiple myeloma. Subcutaneous injection of bortezomib reduced PN, but 24% of cases were grade 2 PN and 6% of cases were grade 3 PN. PN higher than grade 2 was not resolved by subcutaneous injection. PN higher than grade 3 has serious dose limiting toxicity and is the cause of discontinuing bortezomib treatment. Lafutidine is an H2-blocker with gastroprotective activity and is thought to function by increasing mucosal blood flow via capsaicin sensitive neurons. The same activity of lafutidine is considered to improve glossodynia and taxane induced PN. We hypothesized that lafutidine prevents or improves PN that is caused by bortezomib. In the current study, bortezomib was administered in the usual manner (intravenous administration of bortezomib 1.3 mg/m², twice a week for 2 weeks, followed by 1 week without treatment) for up to four cycles to compare our data with other studies. Lafutidine was administered orally at a dose of 10 mg twice daily. In our eight evaluated cases, the total occurrence of PN was four out of eight patients (50%). There were only grade 1 PN (4 out of 8) cases, and no cases higher than grade 2. We conclude that (1) the total occurrence of PN was not improved, (2) there was no PN after the first course, (3) there were only grade 1 cases and there were no cases higher than grade 2, and (4) no cases discontinued bortezomib treatment because of PN. This is the first report showing that lafutidine is useful for the amelioration of bortezomib induced PN.

In silico investigations of potential anabolic treatments in multiple myeloma-induced bone disease

No anabolic drugs are currently approved to treat multiple myeloma (MM)-induced bone disease and the anti-MM agent bortezomib exhibits the anabolic effects in the clinic. In this study, we focus on investigating potential anabolic treatments of MM-induced bone disease using our previously proposed MM-bone model, with the goal for clarifying the underlying molecular/cellular mechanisms. Firstly, a variety of virtual drug treatments are explored by the parametric study to clarify the anabolic-related molecular/cellular mechanisms. The real drug (i.e., bortezomib) treatments are further examined by developing an integrated model with bortezomib to validate the clarified anabolic-related molecular/cellular mechanisms. The simulated responses to the bortezomib treatments that are validated by the clinical data are consistent with the simulated responses to the virtual drug treatments. Our study clarifies that the anabolic effects in the treatment of MM-induced bone disease are associated with promoting the differentiation of bone marrow stromal cells (BMSC) and inhibiting the apoptosis of active osteoblasts, while promoting the differentiation of osteoblast precursors is instead suggested to be associated with the anti-catabolic effects. Compared with the individual anabolic therapies, the anabolic therapies that promote the differentiation of BMSC in combination with the anti-MM/anti-catabolic therapies are found to induce a greater increase in the bone volume, while the anabolic therapies that inhibit the apoptosis of active osteoblasts in combination with the anti-MM/anti-catabolic therapies induce a lower increase in the bone volume. The simulations also suggest that the direct inhibition of bortezomib on the osteoclast activity is probably a redundant mechanism.

Subclinical pretreatment sensory deficits appear to predict the development of pain and numbness in patients with multiple myeloma undergoing chemotherapy

PURPOSE

Chemotherapy-induced peripheral neuropathy is a major complication in the treatment for cancer, including multiple myeloma (MM). Patients may develop painful and non-painful (e.g., numbness) neuropathy symptoms that impair function and often persist after therapy is terminated. This study tested the hypothesis that baseline subclinical neuropathy, as assessed by sensory thresholds, is related to the development of neuropathy symptoms (e.g., pain and numbness) in patients with MM undergoing treatment with chemotherapy.

METHODS

Patients (n = 56) who had undergone two or fewer cycles of induction therapy and who had no evident neuropathy were assessed using quantitative sensory tests to determine multiple-modality sensory thresholds. Patient-reported pain and numbness were assessed through induction therapy (16 weeks) via the MD Anderson Symptom Inventory. A subset of participants (n = 15) continued reporting on their symptoms for an additional 16 weeks ("maintenance phase").

RESULTS

Patients with sharpness detection deficits at baseline (n = 11, 20 % of sample) reported less severe pain and numbness during induction therapy and less numbness during maintenance therapy (P < 0.05). During the maintenance phase, patients with warmth detection deficits (n = 5, 38 % of sample) reported more severe pain and numbness, and those with skin temperature deficits (n = 7, 47 % of maintenance sample) reported more severe pain (P < 0.05). These deficits were related to patient reported difficulty walking, a common symptom of peripheral neuropathy.

CONCLUSION

Our results suggest that baseline subclinical sensory deficits may be related to a patient's risk for developing chemotherapy-induced peripheral neuropathy.

Age and organ damage correlate with poor survival in myeloma patients: meta-analysis of 1435 individual patient data from 4 randomized trials

Thalidomide and bortezomib are extensively used to treat elderly myeloma patients. In these patients, treatment-related side effects are frequent and full drug doses difficult to tolerate. We retrospectively analyzed data from 1435 elderly patients enrolled in 4 European phase III trials including thalidomide and/or bortezomib. After a median follow up of 33 months (95%CI: 10-56 months), 513 of 1435 patients (36%) died; median overall survival was 50 months (95%CI: 46-60 months). The risk of death was increased in patients aged 75 years or over (HR 1.44, 95%CI: 1.20-1.72; P<0.001), in patients with renal failure (HR 2.02, 95%CI: 1.51-2.70; P<0.001), in those who experienced grade 3-4 infections, cardiac or gastrointestinal adverse events during treatment (HR 2.53, 95%CI: 1.75-3.64; P<0.001) and in those who required drug discontinuation due to adverse events (HR 1.67, 95%CI; 1.12-2.51; P=0.01). This increased risk was restricted to the first six months after occurrence of adverse events or drug discontinuation and declined over time. More intensive approaches, such as the combination of bortezomib-thalidomide, negatively affected outcome. Bortezomib-based combinations may overcome the negative impact of renal failure. Age 75 years or over or renal failure at presentation, occurrence of infections, cardiac or gastrointestinal adverse events negatively affected survival. A detailed geriatric assessment, organ evaluation and less intense individualized approaches are suggested in elderly unfit subjects.

Updated survival analysis of a randomized phase III study of subcutaneous versus intravenous bortezomib in patients with relapsed multiple myeloma

The phase III MMY-3021 study compared safety and efficacy of subcutaneous versus intravenous administration of the proteasome inhibitor bortezomib in patients with relapsed myeloma. The initial report demonstrated non-inferior efficacy with subcutaneous versus intravenous bortezomib for the primary end point: overall response rate after four cycles of single-agent bortezomib. We report updated outcome analyses after prolonged follow up. Best response rate (after up to ten cycles of bortezomib ± dexamethasone) remained 52% in each arm, including 23% and 22% complete or near-complete responses with subcutaneous and intravenous bortezomib, respectively. Time to progression (median 9.7 vs. 9.6 months; hazard ratio 0.872, P=0.462), progression-free survival (median 9.3 vs. 8.4 months; hazard ratio 0.846, P=0.319), and overall survival (1-year: 76.4% vs. 78.0%, P=0.788) were comparable with subcutaneous versus intravenous bortezomib. Peripheral neuropathy rates remained significantly lower with subcutaneous versus intravenous bortezomib, with increased rates of improvement/resolution at the time of this analysis.

Health-related quality of life in elderly, newly diagnosed multiple myeloma patients treated with VMP vs. MP: results from the VISTA trial

OBJECTIVES

The phase 3 VISTA study (ClinicalTrials.gov NCT00111319) in transplant-ineligible myeloma patients demonstrated superior efficacy with bortezomib-melphalan-prednisone (VMP; nine 6-wk cycles) vs. melphalan-prednisone (MP) but also increased toxicity. Health-related quality of life (HRQoL; exploratory endpoint) was evaluated using the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30). The phase 3 VISTA study (ClinicalTrials.gov NCT00111319) in transplant-ineligible myeloma patients demonstrated superior efficacy with bortezomib-melphalan-prednisone (VMP; nine 6-wk cycles) vs. melphalan-prednisone (MP) but also increased toxicity. Health-related quality of life (HRQoL; exploratory endpoint) was evaluated using the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30).

METHODS

EORTC QLQ-C30 was administered at screening, on day 1 of each cycle, at the end-of-treatment visit, and every 8 wk until progression. EORTC QLQ-C30 scores were evaluated among patients with a valid baseline and at least one post-baseline HRQoL assessment.

RESULTS

At baseline, domain scores were similar between arms. By cycle 4, mean differences were clinically meaningful for most domains, indicating poorer health status with VMP. From cycle 5 onwards, improvements relative to baseline/MP were observed for all domains with VMP. Mean scores were generally improved by the end-of-treatment assessment vs. baseline in both arms. Among responding patients, mean scores generally improved from time of response to end-of-treatment assessment, substantially driven by patients achieving complete response (CR). Multivariate analysis showed a significant impact of duration of response/CR on improving global health status, pain, and appetite loss scores. Analyses by bortezomib dose intensity indicated better HRQoL in patients receiving lower dose intensity.

CONCLUSIONS

These findings demonstrate clinically meaningful, transitory HRQoL decrements with VMP and relatively lower HRQoL vs. MP during early treatment cycles, associated with the expected additional toxicities. However, HRQoL is not compromised in the long term, recovering by the end-of-treatment visit to be comparable vs. MP.

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.

Chemotherapy-induced peripheral neuropathy in pediatric cancer patients

Chemotherapy forms the backbone of treatment for many types of pediatric cancers, but a main side effect of treatment is chemotherapy-induced peripheral neuropathy (CIPN). Damage to the peripheral nervous system by chemotherapeutic agents can occur at the axon, cell body, or myelin level, and the mechanism of damage differs based on the specific chemotherapeutic agent used. This review provides background on the current knowledge of pathophysiology, assessment, and intervention for CIPN, focusing specifically on issues relevant in pediatric cancers patients. Although specific, standardized measures of CIPN are available for adults, such measures are limited for use in the pediatric populations. Likewise, clinical trials for prevention and treatment of this neuropathy and related symptoms are rare in pediatrics, but some information can be gained from the basic and adult literature.

An overview of the VISTA trial: newly diagnosed, untreated patients with multiple myeloma ineligible for stem cell transplantation

Multiple myeloma, a plasma cell neoplasm, is the second most common hematologic malignancy after non-Hodgkins lymphoma and is responsible for 2% of cancer deaths. Melphalan and prednisone (MP) has been the standard treatment in elderly patients for many decades. The VISTA study evaluated the effect of this combination with or without the first-in-class proteasome inhibitor bortezomib in newly diagnosed myeloma patients who were not candidates for autologous stem cell transplantation. Altogether 682 patients were enrolled and prospectively randomized in this trial. All patients received nine 6-week cycles of oral melphalan (9 mg/m2) and prednisone (60 mg/m2) on days 1–4, either alone or with bortezomib administered intravenously (1.3 mg/m2 on days 1, 4, 8, 11, 22, 25, 29 and 32 during the first four cycles and on days 1, 8, 22, 29 during remaining course of therapy). Median time to progression (the primary end point of the trial) was 24 months in the bortezomib-containing group compared with 16.6 months in the control group (p < 0.001). Response was evaluated in 337 patients receiving bortezomib compared with 331 patients in the control group who received MP alone; the percentages of partial response or better was 71 vs 35% (p < 0.001), with complete response seen in 30 vs 4%, respectively (p < 0.001). Median response duration in both groups was 19.9 versus 13.1 months, respectively. Median overall survival has not been reached in VMP group compared with 43 months in the MP group (p < 0.001), and this benefit is maintained after long term follow-up and subsequent antimyeloma therapies. Hematological adverse events (AEs) were similar in both groups, although patients in the bortezomib group experienced more frequent peripheral sensory neuropathy (including 13% grade 3, with less than 1% grade 4). Overall, the occurrence of grade 3 AEs was higher in patients receiving bortezomib (53 vs 44%, p = 0.02), but the risk of grade 4 AEs was identical (28 vs 27%). These results confirm the superiority of MP plus bortezomib combination over MP therapy in treatment-naive patients with newly diagnosed multiple myeloma who are ineligible for autologous stem cell transplantation.