Repetitive transcranial magnetic stimulation for chemotherapy-induced peripheral neuropathy in multiple myeloma: A pilot study

Objective

Chemotherapy-induced peripheral neuropathy is one of the major toxicities in multiple myeloma patients, often resulting in dose reductions or treatment interruptions. Repetitive transcranial magnetic stimulation is a safe non-invasive neuromodulation therapy with potential benefits for chemotherapy-induced peripheral neuropathy. The objective of this study was to investigate the efficacy of repetitive transcranial magnetic stimulation treatment on chemotherapy-induced peripheral neuropathy in multiple myeloma patients.

Materials and methods

We screened 30 multiple myeloma patients with chemotherapy-induced peripheral neuropathy who underwent repetitive transcranial magnetic stimulation treatment in this study. Prior to and following repetitive transcranial magnetic stimulation treatment, patients were assessed with nerve conduction velocity, visual analog scale and the European Organization of Research and Treatment of Cancer Quality of Life Questionnaire-CIPN 20-item scale (EORTC QLQ-CIPN20). Categorical and continuous variables were analyzed using Fisher's exact test and Mann-Whitney U test respectively. A p-value < 0.05 (2-tailed) was considered statistically significant.

Results

Following repetitive transcranial magnetic stimulation treatment, 24/30 (80.0%) patients reported a reduction in chemotherapy-induced peripheral neuropathy symptoms. Meanwhile, all 15 patients with grade 2 chemotherapy-induced peripheral neuropathy experienced improvements about themselves, compared to 8/10 patient with grade 3 chemotherapy-induced peripheral neuropathy and 1/5 with grade 4 chemotherapy-induced peripheral neuropathy. Visual analog scale scores decreased after repetitive transcranial magnetic stimulation treatment (5.40 ± 1.94 vs 3.10 ± 1.60, p < 0.001). We also observed enhancements in both motor conduction velocity and sensory conduction velocity of patients in bilateral median nerves, posterior tibial nerves, common ulnar nerves and peroneal nerves following repetitive transcranial magnetic stimulation treatment. Analysis of the European Organization of Research and Treatment of Cancer Quality of Life Questionnaire-CIPN 20-item scale data (17.68 ± 8.14 vs 10.50 ± 9.55, p < 0.001) revealed significant reductions in scores. Patients with grade 2-3 (n = 25) exhibited a mean reduction of 8.89 ± 4.24 points, while those with grade 4 (n = 5) showed a difference value of 3.54 ± 3.45, p < 0.001. No adverse events were observed.

Conclusion

Our findings suggest that repetitive transcranial magnetic stimulation is a safe and effective therapeutic approach for ameliorating peripheral nerve injury and alleviating the chemotherapy-induced peripheral neuropathy symptoms in multiple myeloma patients. Early initiation of repetitive transcranial magnetic stimulation treatment may yield more favorable outcomes for these patients.

Adjusted comparison between elotuzumab and carfilzomib in combination with lenalidomide and dexamethasone as salvage therapy for multiple myeloma patients

The lack of a randomized trial comparing carfilzomib (K) versus elotuzumab (Elo) associated with lenalidomide and dexamethasone (Rd) prompted us to assess the relative usefulness of one triplet over the other. Five independent retrospective cohorts of 883 relapsed/refractory multiple myeloma (RRMM) patients, including 300 EloRd and 583 KRd cases, outside clinical trials, entered this non-randomized comparison. KRd cohort accounted for a higher incidence of younger patients, cases with ≥3 lines of therapy, already exposed to lenalidomide, International Staging System (ISS) stage III, and abnormal lactic dehydrogenase (LDH) level compared with EloRd cohort. Moreover, cytogenetic risk categories, detected in roughly one-third of cases, were equally distributed between the two therapy arms. The probability of CR+VGPR response was significantly higher in KRd (n = 314, 53.9%) than in EloRd patients (n = 111, 37.0%). Likewise, the cumulative incidence function of CR+VGPR, taking into account the competitive risk of death, was significantly higher in KRd arm patients than those in the EloRd arm (p = .003). Moreover, KRd treatment significantly reduced the progression or death risk by 46% in an adjusted multivariate analysis (HR: 0.54, 95% CI 0.42-0.69, p < .0001). Finally, in an adjusted illness-progression/death model, the effect of KRd versus EloRd was of higher magnitude among those who achieved CR+VGPR (-39% hazard ratio reduction, p = .02) than among those who achieved < VGPR (-29% hazard ratio reduction, p = .007). With limitations characteristic to any retrospective analysis, this current clinical practice study's overall results demonstrated potential benefits of KRd therapy compared with EloRd. This observation may help the daily clinical practice.

Immunotherapy in multiple myeloma

Despite available therapies, Multiple Myeloma (MM) remains an incurable hematologic malignancy. Over the past three decades, there have been tremendous developments in therapeutic options for MM. In regards to immunotherapy, Daratumumab was the first monoclonal antibody to receive FDA approval for multiple myeloma. Since then, other monoclonal antibodies such as elotuzumab and isatuximab have received FDA approval. Many clinical trials are underway investigating the efficacy of newer immunotherapies. This review summarizes recently presented and/or published data regarding this growing field, specifically regarding monoclonal antibodies, antibody-drug conjugates, bispecific antibodies, and trispecific antibodies.

Clinical and Pharmacologic Features of Monoclonal Antibodies and Checkpoint Blockade Therapy in Multiple Myeloma

Background:

Survival of multiple myeloma patients has considerably improved in the last decades thanks to the introduction of many new drugs, including immunomodulatory agents, proteasome inhibitors and, more recently, monoclonal antibodies.

Methods:

We analyzed the most recent literature focusing on the clinical and pharmacologic aspects of monoclonal antibody-based therapies in multiple myeloma, including monoclonal antibodies directed against plasma cell antigens, as well as checkpoint blockade therapy directed against immune inhibitory molecules, used as single agents or in combination therapy.

Results:

Anti-CD38 monoclonal antibodies including daratumumab, isatuximab and MOR202 have shown outstanding results in relapsed and/or refractory multiple myeloma patients. The addition of daratumumab to bortezomib-dexamethasone or lenalidomidedexamethasone substantially improved patients’ outcome in this patient population. The anti- SLAMF7 molecule elotuzumab in combination with lenalidomide-dexamethasone showed to be superior to lenalidomide-dexamethasone alone, without adding meaningful toxicity. Checkpoint blockade therapy in combination with immunomodulatory agents produced objective responses in more than 50% of treated patients. However, this combination was also associated with an increase in toxicity and a thorough safety evaluation is currently ongoing.

Conclusion:

Monoclonal antibodies are reshaping the standard of care for multiple myeloma and ongoing trials will help physicians to optimize their use in order to further improve patients’ outcome.

Development and validation of a novel risk stratification algorithm for relapsed multiple myeloma

Multiple myeloma (MM) is a malignancy with varying survival outcomes and drivers of disease progression. Existing MM staging tools were developed using data from newly diagnosed patients. As patient characteristics and disease-related factors change between diagnosis and the initiation of second-line (2L) treatment, an unmet need exists for a tool that can evaluate risk of death at first relapse. We have developed a risk stratification algorithm (RSA) using data from patients with MM who were at 2L. Hazard ratios for independent predictors of overall survival (OS) were derived from a Cox models, and individual patient scores were calculated for total risk. K-adaptive partitioning for survival was used to stratify patients into groups based on their scores. Relative risk doubled with ascending risk group; median OSs for patients in group 1 (lowest risk)-4 (highest risk) were 61·6, 29·6, 14·2 and 5·9 months, respectively. Differences in OS between risk groups were significant. Similar stratification was observed when the RSA was applied to an external validation data set. In conclusion, we have developed a validated RSA that can quantify total risk, frailty risk and disease aggressiveness risk, and stratify patients with MM at 2L into groups with profoundly different survival expectations.

Investigational Monoclonal Antibodies in the Treatment of Multiple Myeloma: A Systematic Review of Agents under Clinical Development

BACKGROUND

Immunotherapy for multiple myeloma (MM) has been the focus in recent years due to its myeloma-specific immune responses. We reviewed the literature on non-Food and Drug Administration (FDA) approved monoclonal antibodies (mAbs) to highlight future perspectives. We searched PubMed, EMBASE, Web of Science, Cochrane Library and ClinicalTrials.gov to include phase I/II clinical trials. Data from 39 studies (1906 patients) were included. Of all the agents, Isatuximab (Isa, anti-CD38) and F50067 (anti-CXCR4) were the only mAbs to produce encouraging results as monotherapy with overall response rates (ORRs) of 66.7% and 32% respectively. Isa showed activity when used in combination with lenalidomide (Len) and dexamethasone (Dex), producing a clinical benefit rate (CBR) of 83%. Additionally, Isa used in combination with pomalidomide (Pom) and Dex resulted in a CBR of 73%. Indatuximab Ravtansine (anti-CD138 antibody-drug conjugate) produced an ORR of 78% and 79% when used in combination with Len-Dex and Pom-Dex, respectively.

CONCLUSIONS

Combination therapy using mAbs such as indatuximab, pembrolizumab, lorvotuzumab, siltuximab or dacetuzumab with chemotherapy agents produced better outcomes as compared to monotherapies. Further clinical trials investigating mAbs targeting CD38 used in combination therapy are warranted.

Emerging immune targets for the treatment of multiple myeloma

We reviewed emerging immune strategies for multiple myeloma (MM) therapy excluding US FDA approved drugs. In relapsed refractory MM, isatuximab (anti-CD38) monotherapy achieved overall response (OR) of 24%. Other monoclonal antibodies that have shown efficacy in combination therapy include siltuximab (OR: 66%), indatuximab (OR: 78%), isatuximab (OR: 64.5%), pembrolizumab (OR: 60%), bevacizumab (OR: 70%), dacetuzumab (OR: 39%) and lorvotuzumab (OR: 56.4%). No OR was observed with monotherapy using BI-505, siltuximab, bevacizumab, AVE-1642, figitumumab, atacicept, milatuzumab, dacetuzumab, lucatumumab, IPH2101, lorvotuzumab, BT062 and nivolumab. We included seven clinical trials on chimeric antigen receptor (CAR) T cells. CAR T-cell targets include BCMA, CD19, KLC and CD138. A recent experience of CAR T-cell (B-cell maturation antigen) therapy in advanced MM has shown global response of 100%. The future of monoclonal antibodies and adoptive T cells for MM treatment seems promising.

Modern multiple myeloma therapy: deep, sustained treatment response and good clinical outcomes

In the USA at the beginning of this century, the average overall survival in patients with multiple myeloma was about 3 years. Around that time, three drugs (bortezomib, lenalidomide and thalidomide) were introduced for the treatment of multiple myeloma and, in 2012, carfilzomib received accelerated approval by the US Food and Drug Administration (FDA). Driven by access to better drugs, median overall survival in younger patients (aged <50 years) was >10 years by 2014. The FDA approved 14 new drugs for the treatment of cancer in 2015; four of these were approved for the treatment of myeloma (panobinostat, daratumumab, elotuzumab and ixazomib). In 2015 and 2016, expanded label indications were approved by the FDA for lenalidomide and carfilzomib, respectively. The recent increase in approved, highly effective combination therapies for patients with multiple myeloma has led the way to redefining the goals of therapy. Here, we review and provide a clinical perspective on the treatment goals and management of multiple myeloma in the era of modern therapy. Recent meta-analyses show that minimal residual disease (MRD) negativity is associated with longer progression-free and overall survival in patients with multiple myeloma. With the use of modern combination therapy, large proportions (>60-70%) of newly diagnosed multiple myeloma patients achieve complete responses and MRD negativity. Modern combination therapies induce rapid, deep and sustainable responses (including MRD negativity), supporting a treatment paradigm shift away from palliative two-drug combinations towards the use of modern, potent, three- or four-drug combination regimens in early lines of therapy. Data support the use of modern therapy upfront rather than reserving it for later stages of the disease. As survival time increases with modern combination therapies, development of early reliable surrogate end-points for survival, such as MRD negativity, are needed for expedited read-out of future randomized clinical trials.

Renal Toxicities of Novel Agents Used for Treatment of Multiple Myeloma

Survival for patients with multiple myeloma has significantly improved in the last decade in large part due to the development of proteasome inhibitors and immunomodulatory drugs. These next generation agents with novel mechanisms of action as well as targeted therapies are being used both in the preclinical and clinical settings for patients with myeloma. These agents include monoclonal antibodies, deacetylase inhibitors, kinase inhibitors, agents affecting various signaling pathways, immune check point inhibitors, and other targeted therapies. In some cases, off target effects of these therapies can lead to unanticipated effects on the kidney that can range from electrolyte disorders to AKI. In this review, we discuss the nephrotoxicities of novel agents currently in practice as well as in development for the treatment of myeloma.

Monoclonal antibodies - A new era in the treatment of multiple myeloma

Monoclonal antibodies (mAbs) are currently the most investigated therapeutic compounds in oncology, but there is no monoclonal antibody approved in the treatment of multiple myeloma (MM). Nevertheless several really promising molecules are under investigation in phase III clinical trials. Dominantly daratumumab (anti-CD38) and elotuzumab (anti-CS1) showed extraordinary effectiveness in phase I/II trials. The toxicity was acceptable which is important for their addition to standard anti-myeloma agents like proteasome inhibitors or immunomodulatory drugs. Monoclonal antibodies such as denosumab (anti-RANKL) or BHQ880 (anti-DKK-1) are investigated also in the management of myeloma bone disease. This review is focused on the most promising mAbs, their mechanisms of action and the rationale of use. Practically all available results have been described. If the ongoing trials confirm the efficacy and safety of mAbs, they would become an important part of MM treatment that would be translated in the further improvement of therapeutic outcomes.

Monoclonal antibodies in the treatment of multiple myeloma: current status and future perspectives

The treatment landscape for patients with multiple myeloma (MM) is constantly evolving. Over the past decade, the introduction of novel agents such as proteasome inhibitors and immunomodulatory drugs has led to notable changes in therapeutic strategy, and improvements in survival, yet MM remains incurable in the vast majority of cases. More recently, a targeted approach to MM treatment has emerged, using monoclonal antibodies (mAbs) to target antigens expressed on the surface of MM cells. MAbs tested to date kill MM cells via the host's immune system and/or by promoting apoptosis, and appear to have generally improved tolerability compared with currently available treatments. Due to their distinct mode of action, mAbs are promising both for patients who have exhausted current regimens, and as part of first-line treatments in newly diagnosed patients. This review examines the recent developments in mAb-based therapy for MM, primarily focused on those agents in ongoing clinical testing.