Current strategies for treatment of relapsed/refractory multiple myeloma

Identification and study of cuproptosis-related genes in prognostic model of multiple myeloma

BACKGROUND

Multiple myeloma (MM) is a highly heterogeneous disease. Cuproptosis is a novel mode of death that is closely associated with several diseases, such as hepatocellular carcinoma. However, its role in MM is unknown.

METHODS

MM transcriptomic and clinical data were obtained from UCSC Xena and gene expression omnibus (GEO) databases. Following MM samples were divided into different subtypes based on the cuproptosis genes, the differentially expressed genes (DEGs) among different subtypes, namely, candidate cuproptosis related genes were analyzed by univariate Cox and least absolute shrinkage and selection operator (LASSO) regression to construct a cuproptosis-related risk model. After the independent prognostic analysis was performed, a nomogram was constructed. Finally, Functional enrichment analysis and immune infiltration analysis were performed in the high- and low-risk groups, potential therapeutic agents were then predicted.

RESULTS

The 784 MM samples in UCSC Xena cohorts were divided into three different subtypes, and 4 out of 346 candidate cuproptosis related genes, namely CDKN2A, BCL3, KCNA3 and TTC14 were used to construct a risk model. Risk score was considered a reliable independent prognostic factor for MM patients. It was investigated that the pathway of cell cycle was significantly enriched in the high-risk group. In addition, immune score, ESTIMATE score and cytolytic activity were significantly different between different risk groups, as well as 13 immune cells such as memory B cells. Nine drugs were predicted in our study.

CONCLUSION

A cuproptosis-related prognostic model was constructed, which may have a potential guiding role in the treatment of MM.

Management of Adverse Reactions for BCMA-Directed Therapy in Relapsed Multiple Myeloma: A Focused Review

Anti-B-cell maturation antigen therapies consisting of bispecific antibodies, antibody-drug conjugates, and chimeric antigen receptor T cells have shown promising results in relapsed refractory multiple myeloma (RRMM). However, the severe side effects include cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, cytopenia(s), infections, hemophagocytic lymphohistiocytosis, and organ toxicity, which could sometimes be life-threatening. This review focuses on these most common complications post-BCMA therapy. We discussed the risk factors, pathogenesis, clinical features associated with these complications, and how to prevent and treat them. We included four original studies for this focused review. All four agents (idecabtagene vicleucel, ciltacabtagene autoleucel, teclistamab, belantamab mafodotin) have received FDA approval for adult RRMM patients. We went through the FDA access data packages of the approved agents to outline stepwise management of the complications for better patient outcomes.

Patient Confidence and Information Preferences during the Treatment Decision-making Process: Results from a Large Multiple Myeloma Patient Survey Across 12 Countries in Europe and Israel

BACKGROUND

The relapsing nature of multiple myeloma (MM) means that patients typically receive different and multiple lines of therapy, requiring many treatment decisions over the disease course. The aim of this study was to explore patient confidence and information preferences during the treatment decision-making process.

PATIENTS AND METHODS

A multinational, cross-sectional survey enrolled patients with MM. It was co-developed and distributed by Myeloma Patients Europe across 12 countries in Europe and Israel from May 2019 to March 2020. Eligibility criteria included a self-reported diagnosis of MM and being able to recall the decision-making process at the start of their latest treatment line.

RESULTS

A total of 1559 patients were included, with complete responses received from 1081 (69%) patients. The median age range was 54 to 64 years; there was an equal gender split and 57% had their latest treatment decision made within the past year. Overall, 54% of patients felt "very confident" in the latest treatment decision. Patients deemed the most important information to be safety/tolerability and treatment effectiveness, but the latter was among the least frequently received. Most patients reported that their primary physician treating MM was their main source for all types of information (range, 62%-94%), with 87% of patients reporting a "very good" or "good" relationship with them.

CONCLUSION

Over half of patients felt very confident in their latest treatment decision; however, patients reported not routinely receiving important treatment effectiveness information. Addressing the discrepancies between information that patients receive and consider important may enhance confidence in decision-making.

Real-world use of carfilzomib combined with lenalidomide and dexamethasone in patients with multiple myeloma in Europe and Israel

Clinical trials have demonstrated the efficacy and safety of carfilzomib in patients with relapsed/refractory multiple myeloma (RRMM); however, prospective real-world data are limited. This real-world, prospective, observational study evaluated carfilzomib use, effectiveness and safety in adults with RRMM. Data are presented for a subset of patients (n = 383) who received carfilzomib in combination with lenalidomide and dexamethasone (KRd). The overall response rate (ORR) was 83.6% among 360 evaluable patients. Treatment responses were better when KRd was administered at earlier therapy lines than at later lines of therapy (ORR: second line, 85.3%; third line or later, 81.0%). In patients with the anti-CD38 antibody-refractory disease, ORR was higher when KRd was administered earlier than at later therapy lines (second line/third line, 75.0%; fourth line or later, 60.0%). An ORR of 68.1% and 82.0% was achieved in the lenalidomide-refractory and not lenalidomide-refractory subgroups, respectively. KRd was consistently administered per the European label (twice weekly dose of 27 mg/m²) and the median time to discontinuation was 14.6 months. The safety profile of KRd was consistent with previous studies. These real-world data highlight the effectiveness of KRd as a treatment for patients with RRMM, including those with disease refractory to lenalidomide or anti-CD38 antibodies.

Safety and efficacy of daratumumab in Chinese patients with relapsed or refractory multiple myeloma: a phase 1, dose-escalation study (MMY1003)

Daratumumab monotherapy demonstrated favorable safety and efficacy in relapsed/refractory multiple myeloma (RRMM) patients in the global phase 1/2 GEN501 and phase 2 SIRIUS studies. MMY1003 evaluated daratumumab monotherapy specifically in Chinese patients with RRMM. This 3-part, open-label, phase 1, dose-escalation study included patients with ≥ 2 prior lines of therapy. Part 3 included patients who had received a proteasome inhibitor (PI) and immunomodulatory drug (IMiD) and experienced disease progression on their last regimen. Patients received intravenous daratumumab 8 mg/kg or 16 mg/kg in part 1 and 16 mg/kg in parts 2 + 3. Primary endpoints were dose-limiting toxicity (DLT; part 1), pharmacokinetics (parts 1 + 2), and adverse events (AEs). Fifty patients enrolled. The first 3 patients in part 1 received daratumumab 8 mg/kg; remaining patients in parts 1–3 received daratumumab 16 mg/kg. In the daratumumab 16 mg/kg group (n = 47), patients received a median of 4 prior lines of therapy; 32% were refractory to a PI and IMiD, and 79% were refractory to their last prior therapy. No DLTs occurred. Thirty-six (77%) patients reported grade 3/4 treatment-emergent AEs. Thirteen (28%) patients experienced infusion-related reactions. At an 18.5-month median follow-up, overall response rate was 43%. Median progression-free survival (PFS) and overall survival (OS) were 6.7 months and not reached, respectively; 12-month PFS and OS rates were 35% and 70%. Pharmacokinetic results (n = 22) were consistent with other studies. Safety, pharmacokinetics, and efficacy of daratumumab monotherapy were confirmed in Chinese patients with RRMM. This trial is registered on ClinicalTrials.gov (NCT02852837).

B-cell maturation antigen targeting strategies in multiple myeloma treatment, advantages and disadvantages

B cell maturation antigen (BCMA), a transmembrane glycoprotein member of the tumor necrosis factor receptor superfamily 17 (TNFRSF17), highly expressed on the plasma cells of Multiple myeloma (MM) patients, as well as the normal population. BCMA is used as a biomarker for MM. Two members of the TNF superfamily proteins, including B-cell activating factor (BAFF) and A proliferation-inducing ligand (APRIL), are closely related to BCMA and play an important role in plasma cell survival and progression of MM. Despite the maximum specificity of the monoclonal antibody technologies, introducing the tumor-specific antigen(s) is not applicable for all malignancies, such as MM that there plenty of relatively specific antigens such as GPCR5D, MUC1, SLAMF7 and etc., but higher expression of BCMA on these cells in comparison with normal ones can be regarded as a relatively exclusive marker. Currently, different monoclonal antibody (mAb) technologies applied in anti-MM therapies such as daratuzumab, SAR650984, GSK2857916, and CAR-T cell therapies are some of these tools that are reviewed in the present manuscript. By the way, the structure, function, and signaling of the BCMA and related molecule(s) role in normal plasma cells and MM development, evaluated as well as the potential side effects of its targeting by different CAR-T cells generations. In conclusion, BCMA can be regarded as an ideal molecule to be targeted in immunotherapeutic methods, regarding lower potential systemic and local side effects.

Real-world evidence for carfilzomib dosing intensity on overall survival and treatment progression in multiple myeloma patients

INTRODUCTION

Carfilzomib dosing as a single agent or in combination with dexamethasone (Kd) has evolved from the initial 27 mg/m² twice-weekly (legacy dose), to more recently approved doses of 56 mg/m² twice-weekly and 70 mg/m² once-weekly (optimized doses). The objective of this study was to evaluate the overall survival (OS), and time to next treatment (TTNT) among multiple myeloma patients treated with Kd optimized vs legacy doses.

METHODS

A retrospective analysis of patients receiving Kd between 01/01/2013-07/31/2017 was conducted using IQVIA's oncology electronic medical records database. Kd dose was estimated based on body surface area. OS was measured from the Kd-initiation date until death. TTNT was defined as the time from Kd-initiation until the start of subsequent treatment. Kaplan-Meier analysis and Cox models were used to evaluate OS and TTNT.

RESULTS

Of the 1,469 patients evaluated, 129 (8.8%) received optimized dose and 1,340 (91.2%) received legacy dose. Risk of mortality was 64% lower for patients receiving the optimized doses (HR: 0.36, 95% CI: 0.178-0.745). Patients receiving the optimized doses had significantly longer TTNT compared to patients receiving the legacy dose (median TTNT: 17.5 months [95% CI: 14.8-NE] and 13.2 months, [95% CI: 12.4-14.4], respectively; p = 0.023), and 33% lower risk of progressing to the subsequent treatment (HR: 0.67, 95% CI: 0.48-0.93).

CONCLUSIONS

Patient outcomes could be improved if eligible MM patients are treated with the optimized, recently approved Kd doses (56 mg/m² twice-weekly and 70 mg/m² once-weekly).

A phase I study of anti-BCMA CAR T cell therapy in relapsed/refractory multiple myeloma and plasma cell leukemia

BACKGROUND

Relapsed/refractory (R/R) multiple myeloma (MM) patients and primary plasma cell leukemia (PCL) have an unfavorable prognosis and no effective treatment. This study was designed to assess the safety and preliminary efficacy of a novel anti-B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T cell in R/R MM and PCL.

METHODS

Between February 22, 2017, and June 25, 2018, 28 R/R and two R/R primary PCL patients received a median dose of 11.2 × 106 CAR+ cells/kg. The subjects were refractory to a proteasome inhibitor and/or an immunomodulatory agent. Fludarabine and cyclophosphamide were given as lymphodepletion chemotherapy.

RESULTS

Results for these 30 consecutive patients who received an anti-BCMA CAR T cell infusion are reported. The patients had received a median of four prior lines of therapy. A total of 44 different types of adverse events were recorded, and hematologic toxic effects were the most common events of any grade during treatment. Hematologic toxic effects were also the most common events of grade 3 or higher. A total of 29 patients (96.7%) had cytokine release syndrome, which was of grade 1 or 2 in 24 patients (80%) and grade 3 in five patients (16.7%). Neurologic toxic effects only occurred in one patient (3.3%) and were of grade 1. The objective response rate was 90%, and the complete response rate was 43.3%. With a median follow-up of 12.6 months, the median progression-free survival (PFS) and overall survival were 5.2 months and 14.0 months. One of the two primary PCL achieved a complete response with a PFS of 307 days. The other patients achieved a very good partial response with a PFS of 117 days.

CONCLUSIONS

Anti-BCMA CAR T cell treatment is safe and highly active in R/R multiple myeloma.

Daratumumab Monotherapy for Relapsed or Refractory Multiple Myeloma: Results of an Early Access Treatment Protocol in Europe and Russia

Introduction

Daratumumab is a human IgGκ monoclonal antibody targeting CD38. Despite the demonstrated benefit of daratumumab in multiple myeloma, not all patients have access to commercially available daratumumab. Here we report a pooled analysis of patients from the UK, Spain, Italy, and Russia enrolled in an open-label, early access treatment protocol (EAP) that provided daratumumab (16 mg/kg) monotherapy to patients with heavily pre-treated relapsed or refractory multiple myeloma (RRMM).

Methods

Intravenous daratumumab 16 mg/kg was administered to patients who had received ≥ 3 prior lines of therapy, including a proteasome inhibitor (PI) and an immunomodulatory drug (IMiD), or who were double refractory to both a PI and an IMiD. Safety and patient-reported outcomes data were collected.

Results

A total of 293 patients received  ≥ 1 dose of daratumumab. The median duration of daratumumab exposure was 4.2 (range 0.03–24.1) months, with a median number of 13 (range 1–37) infusions. The overall response rate was 33.1%, and the median progression-free survival was 4.63 months. Grade 3/4 treatment-emergent adverse events occurred in 60.1% of patients, of which the most common were thrombocytopenia (18.8%), anemia (11.9%), and neutropenia (11.6%). The most common serious adverse events were pneumonia (4.4%) and pyrexia (4.1%). Infusion-related reactions occurred in 45.1% of patients. The median change from baseline in all domains of patient-reported outcome instruments (European Quality of Life Five Dimensions Questionnaire [EQ-5D–5L], European Organisation for Research and Treatment of Cancer [EORTC] Quality of Life Questionnaire [QLQ-C30], and EORTC Multiple Myeloma Module [QLQ-MY20]) was generally 0 or close to 0.

Conclusion

These EAP results are consistent with those from previous trials of daratumumab monotherapy and confirm its safety in patients from Europe and Russia with heavily pre-treated RRMM.

Trial Registration

ClinicalTrials.gov identifier, NCT02477891.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40487-020-00137-x.

Immunotherapeutic strategies targeting B cell maturation antigen in multiple myeloma

Multiple myeloma (MM) is the second most common hematologic malignancy, and is characterized by the clonal expansion of malignant plasma cells. Despite the recent improvement in patient outcome due to the use of novel therapeutic agents and stem cell transplantation, all patients eventually relapse due to clone evolution. B cell maturation antigen (BCMA) is highly expressed in and specific for MM cells, and has been implicated in the pathogenesis as well as treatment development for MM. In this review, we will summarize representative anti-BCMA immune therapeutic strategies, including BCMA-targeted vaccines, anti-BCMA antibodies and BCMA-targeted CAR cells. Combination of different immunotherapeutic strategies of targeting BCMA, multi-target immune therapeutic strategies, and adding immune modulatory agents to normalize anti-MM immune system in minimal residual disease (MRD) negative patients, will also be discussed.

Results of an Early Access Treatment Protocol of Daratumumab Monotherapy in Spanish Patients With Relapsed or Refractory Multiple Myeloma

Daratumumab is a human CD38-targeted monoclonal antibody approved as monotherapy for heavily pretreated relapsed and refractory multiple myeloma. We report findings for the Spanish cohort of an open-label treatment protocol that provided early access to daratumumab monotherapy and collected safety and patient-reported outcomes data for patients with relapsed or refractory multiple myeloma. At 15 centers across Spain, intravenous daratumumab (16 mg/kg) was administered to 73 patients who had ≥3 prior lines of therapy, including a proteasome inhibitor and an immunomodulatory drug, or who were double refractory to both. The median duration of daratumumab treatment was 3.3 (range: 0.03–13.17) months, with a median number of 12 (range: 1–25) infusions. Grade 3/4 treatment-emergent adverse events were reported in 74% of patients and included lymphopenia (28.8%), thrombocytopenia (27.4%), neutropenia (21.9%), leukopenia (19.2%), and anemia (15.1%). Common (>5%) serious treatment-emergent adverse events included respiratory tract infection (9.6%), general physical health deterioration (6.8%), and back pain (5.5%). Infusion-related reactions occurred in 45% of patients. The median change from baseline in all domains of the EQ-5D-5L and EORTC QLQ-C30 was mostly 0. A total of 18 (24.7%) patients achieved a partial response or better, with 10 (13.7%) patients achieving a very good partial response or better. Median progression-free survival was 3.98 months. The results of this early access treatment protocol are consistent with previously reported trials of daratumumab monotherapy and confirm its safety and antitumoral efficacy in Spanish patients with heavily treated relapsed or refractory multiple myeloma.

European Clinical Trials Database number: 2015-002993-19

Disulfiram/copper markedly induced myeloma cell apoptosis through activation of JNK and intrinsic and extrinsic apoptosis pathways

Disulfiram (DSF) is an FDA approved anti-alcoholism drug in use for more than 60 years. Recently, antitumor activity of the DSF/copper (DSF/Cu) complex has been identified. Its anti-multiple myeloma activity, however, has barely been investigated. In the present study, our results demonstrated that the DSF/Cu complex induced apoptosis of MM cells and MM primary cells. The results indicated that DSF/Cu significantly induced cell cycle arrest at the G2/M phase in MM.1S and RPMI8226 cells. Moreover, JC-1 and Western blot results showed that DSF/Cu disrupted mitochondrial membrane integrity and cleaved caspase-8 in MM cells, respectively, suggesting that it induced activation of extrinsic and intrinsic apoptosis pathways. Interestingly, DSF/Cu induced caspase-3 activation was partly blocked by Z-VAD-FMK (zVAD), a pan-caspase inhibitor, indicating at caspase-dependent and -independent paths involved in DSF/Cu induced myeloma cell apoptosis machinery. Additionally, activation of the c-Jun N-terminal kinase (JNK) signaling pathway was observed in DSF/Cu treated MM cells. More importantly, our results demonstrated that DSF/Cu significantly reduced tumor volumes and prolonged overall survival of MM bearing mice when compared with the controls. Taken together, our novel findings showed that DSF/Cu has potent anti-myeloma activity in vitro and in vivo highlighting valuable clinical potential of DSF/Cu in MM treatment.

Bortezomib Treatment Modulates Autophagy in Multiple Myeloma

Although the introduction of bortezomib as a therapeutic strategy has improved the overall survival of multiple myeloma (MM) patients, 15–20% of high-risk patients do not respond to bortezomib over time or become resistant to treatment. Therefore, the development of new therapeutic strategies, such as combination therapies, is urgently needed. Methods: Given that bortezomib resistance may be mediated by activation of the autophagy pathway as an alternative mechanism of protein degradation, and that an enormous amounts of misfolded protein is generated in myeloma plasma cells (PCs), we investigated the effect of the simultaneous inhibition of proteasome by bortezomib and autophagy by hydroxychloroquine (HCQ) treatment on PCs and endothelial cells (ECs) isolated from patients with monoclonal gammopathy of undetermined significance (MGUS) and MM. Results: We found that bortezomib combined with HCQ induces synergistic cytotoxicity in myeloma PCs whereas this effect is lost on ECs. Levels of microtubule-associated protein light chain beta (LC3B) and p62 are differentially modulated in PCs and ECs, with effects on cell viability and proliferation. Conclusions: Our results suggest that treatment with bortezomib and HCQ should be associated with an anti-angiogenic drug to prevent the pro-angiogenic effect of bortezomib, the proliferation of a small residual tumor PC clone, and thus the relapse.

A single-center retrospective cohort analysis of venetoclax in relapsed/refractory multiple myeloma

Venetoclax, a small molecule inhibitor of BCL-2, has promising pre-clinical and early clinical activity in relapsed refractory multiple myeloma (RRMM). However, the clinical use of venetoclax remains under evaluation. We performed a single-center, retrospective analysis of patients with RRMM treated with off-label venetoclax. Forty-seven patients with a median of seven lines of prior therapy were identified. Most patients (87%) received venetoclax plus proteasome inhibitor, though there was heterogeneity in the venetoclax-containing regimen patients received, and 38% had known t(11;14). The overall response rate (ORR) was 39%, with 17% achieving ≥ very good partial response (VGPR). In the t(11;14) cohort, the ORR was 71%, with 24% achieving ≥ VGPR. The median progression-free survival was 2.1 months and overall survival was 15.6 months. One treatment-related death (related to infection) occurred. Venetoclax appears safe and efficacious in patients with RRMM, especially in those with t(11;14). Prospective trials are ongoing to further evaluate this treatment.

The effects of different schedules of bortezomib, melphalan, and prednisone for patients with newly diagnosed multiple myeloma who are transplant ineligible: a matching-adjusted indirect comparison

For patients with newly diagnosed multiple myeloma (NDMM) who are transplant ineligible, bortezomib-melphalan-prednisone (VMP) demonstrated superior efficacy based on the VISTA trial. In subsequent trials, twice-weekly bortezomib was limited to the first cycle or completely replaced with once-weekly bortezomib to reduce toxicity. Following a systematic literature review, the efficacy and safety of modified VMP schedules (pooled data from the once-weekly bortezomib VMP arm of the GIMEMA trial and the VMP arm of the ALCYONE trial) were compared to the VISTA schedule using naïve and unanchored matching-adjusted indirect comparison (MAIC). Median progression-free survival was similar between VISTA and modified VMP (20.7 months [95% CI, 18.4-24.3] vs 19.6 months [95% CI, 18.8-21.0]). Peripheral neuropathy was significantly reduced with modified VMP versus VISTA VMP (all grades: naïve, 32.1% vs 46.8% and MAIC, 32.1% vs 46.7%; both p < .0001). These findings support a modified VMP dosing schedule for patients with NDMM who are transplant ineligible.

The Clinical Pharmacology of Elotuzumab

Novel treatment options are needed to improve long-term outcomes for patients with multiple myeloma (MM). In this article, we comprehensively review the clinical pharmacology of elotuzumab, a first-in-class monoclonal anti-SLAMF7 antibody approved in combination with lenalidomide and dexamethasone (ELd) for the treatment of patients with MM and one to three prior therapies. Elotuzumab has a dual mechanism of action to specifically kill myeloma cells: binding SLAMF7 on myeloma cells facilitates natural killer (NK) cell-mediated antibody-dependent cellular cytotoxicity (ADCC), and direct engagement of SLAMF7 on NK cells further enhances NK cell activity. Elotuzumab administration causes transient elevations of selected cytokines (tumor necrosis factor-α, interferon-γ-induced protein-10 and monocyte chemoattractant protein-1). The temporary nature of these elevations (greatest after the first dose, with a trend to return to baseline by day 7) suggests a low likelihood of facilitating clinically meaningful drug-drug interactions. Elotuzumab exposure increases more than proportionally to dose and >80% SLAMF7 receptor occupancy is achieved with the approved elotuzumab 10 mg/kg regimen. Population pharmacokinetic data from 375 patients demonstrated weight-based dosing is appropriate for elotuzumab, and that ethnicity and hepatic/renal function have minimal effects on exposure. Exposure-response analysis of patients treated with ELd demonstrated that increased elotuzumab exposure does not elevate the risk of grade 3+ adverse events (AEs) or AEs leading to discontinuation/death. Elotuzumab antidrug antibodies occurred in 18.5% of patients treated with ELd or elotuzumab plus bortezomib and dexamethasone, but were generally transient and did not affect elotuzumab efficacy or safety. A monotherapy study indicated elotuzumab does not have clinically relevant effects on QT intervals.

Special problems in the management of elderly patients with multiple myeloma

Multiple myeloma (MM) is a neoplastic disease typical of the elderly. Many steps forward have been made in the characterization of patients, and new treatment strategies are available today. Clinical trials represent a major point in the definition of standard treatment, although they usually include fit patients, while frail patients are commonly excluded. Therefore, frail patients may receive treatments that may be too toxic, thus jeopardizing the beneficial effects of therapy. A careful patient assessment is crucial to better characterize patients and consequently to appropriately select treatment. Future trials testing novel agent-based therapies in different subsets of patients will shed light on this important issue and will allow patients to receive appropriate, tailored treatments.

Response to therapeutic monoclonal antibodies for multiple myeloma in African Americans versus whites

BACKGROUND

Myeloma occurs disproportionately in African Americans, with disparities in outcomes potentially caused by access to care, cytogenetics, and immunity. A gap in knowledge of immune function dissimilarities between African Americans and whites exists. Data for other diseases suggest innate differences in immunity and inflammatory markers, with potential implications for therapeutic monoclonal antibodies reliant on secondary immune activation for activity.

METHODS

Patients receiving daratumumab or elotuzumab, lenalidomide, and dexamethasone were retrospectively studied with a primary endpoint of response at 2 (daratumumab) or 4 months (elotuzumab). Secondary endpoints included stable disease or better at the same points, treatment duration, time to best response, and adverse events.

RESULTS

Eighty patients were included; baseline characteristics were balanced with the exception of the stage at diagnosis, which was more advanced in African Americans. No statistically significant difference in response was seen: 37.9% in whites versus 11.8% in African Americans with daratumumab (P = .090) and 60% in whites versus 44% in African Americans with elotuzumab (P = .462). There were no differences in the duration of treatment, the time to best response, or adverse events. Common potential immune-related adverse events in both arms were fatigue (39%), back pain (30%), and infusion reactions (40%). Anemia was significantly associated with a response to daratumumab (P = .02); no patients without anemia responded at 2 months, whereas 34.4% of patients with anemia did.

CONCLUSIONS

No significant difference in response, duration of treatment, or time to response was seen by race, although a trend toward greater early response rates in whites was observed. In these cohorts, as in other analyses, African American patients tended to present with later stage disease.

Targeting B Cell Maturation Antigen (BCMA) in Multiple Myeloma: Potential Uses of BCMA-Based Immunotherapy

The approval of the first two monoclonal antibodies targeting CD38 (daratumumab) and SLAMF7 (elotuzumab) in late 2015 for treating relapsed and refractory multiple myeloma (RRMM) was a critical advance for immunotherapies for multiple myeloma (MM). Importantly, the outcome of patients continues to improve with the incorporation of this new class of agents with current MM therapies. However, both antigens are also expressed on other normal tissues including hematopoietic lineages and immune effector cells, which may limit their long-term clinical use. B cell maturation antigen (BCMA), a transmembrane glycoprotein in the tumor necrosis factor receptor superfamily 17 (TNFRSF17), is expressed at significantly higher levels in all patient MM cells but not on other normal tissues except normal plasma cells. Importantly, it is an antigen targeted by chimeric antigen receptor (CAR) T-cells, which have already shown significant clinical activities in patients with RRMM who have undergone at least three prior treatments, including a proteasome inhibitor and an immunomodulatory agent. Moreover, the first anti-BCMA antibody–drug conjugate also has achieved significant clinical responses in patients who failed at least three prior lines of therapy, including an anti-CD38 antibody, a proteasome inhibitor, and an immunomodulatory agent. Both BCMA targeting immunotherapies were granted breakthrough status for patients with RRMM by FDA in Nov 2017. Other promising BCMA-based immunotherapeutic macromolecules including bispecific T-cell engagers, bispecific molecules, bispecific or trispecific antibodies, as well as improved forms of next generation CAR T cells, also demonstrate high anti-MM activity in preclinical and even early clinical studies. Here, we focus on the biology of this promising MM target antigen and then highlight preclinical and clinical data of current BCMA-targeted immunotherapies with various mechanisms of action. These crucial studies will enhance selective anti-MM response, transform the treatment paradigm, and extend disease-free survival in MM.

Cross Talk Networks of Mammalian Target of Rapamycin Signaling With the Ubiquitin Proteasome System and Their Clinical Implications in Multiple Myeloma

Multiple myeloma (MM) is the second most common hematological malignancy and results from the clonal amplification of plasma cells. Despite recent advances in treatment, MM remains incurable with a median survival time of only 5-6years, thus necessitating further insights into MM biology and exploitation of novel therapeutic approaches. Both the ubiquitin proteasome system (UPS) and the PI3K/Akt/mTOR signaling pathways have been implicated in the pathogenesis, and treatment of MM and different lines of evidence suggest a close cross talk between these central cell-regulatory signaling networks. In this review, we outline the interplay between the UPS and mTOR pathways and discuss their implications for the pathophysiology and therapy of MM.

Diagnosis of Plasma Cell Dyscrasias and Monitoring of Minimal Residual Disease by Multiparametric Flow Cytometry

Plasma cell dyscrasia (PCD) is a heterogeneous disease that has seen a tremendous change in outcomes due to improved therapies. Over the past few decades, multiparametric flow cytometry has played an important role in the detection and monitoring of PCDs. Flow cytometry is a high-sensitivity assay for early detection of minimal residual disease (MRD) that correlates well with progression-free survival and overall survival. Before flow cytometry can be effectively implemented in the clinical setting, sample preparation, panel configuration, analysis, and gating strategies must be optimized to ensure accurate results. Current consensus methods and reporting guidelines for MRD testing are discussed.

Pomalidomide, bortezomib and low-dose dexamethasone in lenalidomide-refractory and proteasome inhibitor-exposed myeloma

This phase 1 dose-escalation study evaluated pomalidomide, bortezomib (subcutaneous (SC) or intravenous (IV)) and low-dose dexamethasone (LoDEX) in lenalidomide-refractory and proteasome inhibitor-exposed relapsed or relapsed and refractory multiple myeloma (RRMM). In 21-day cycles, patients received pomalidomide (1-4 mg days 1-14), bortezomib (1-1.3 mg/m2 days 1, 4, 8 and 11 for cycles 1-8; days 1 and 8 for cycle ⩾9) and LoDEX. Primary endpoint was to determine the maximum tolerated dose (MTD). Thirty-four patients enrolled: 12 during escalation, 10 in the MTD IV bortezomib cohort and 12 in the MTD SC bortezomib cohort. Patients received a median of 2 prior lines of therapy; 97% bortezomib exposed. With no dose-limiting toxicities, MTD was defined as the maximum planned dose: pomalidomide 4 mg, bortezomib 1.3 mg/m2 and LoDEX. All patients discontinued treatment by data cutoff (2 April 2015). The most common grade 3/4 treatment-emergent adverse events were neutropenia (44%) and thrombocytopenia (26%), which occurred more frequently with IV than SC bortezomib. No grade 3/4 peripheral neuropathy or deep vein thrombosis was reported. Overall response rate was 65%. Median duration of response was 7.4 months. Pomalidomide, bortezomib and LoDEX was well tolerated and effective in lenalidomide-refractory and bortezomib-exposed patients with RRMM.

Monoclonal Antibody: A New Treatment Strategy against Multiple Myeloma

2015 was a groundbreaking year for the multiple myeloma community partly due to the breakthrough approval of the first two monoclonal antibodies in the treatment for patients with relapsed and refractory disease. Despite early disappointments, monoclonal antibodies targeting CD38 (daratumumab) and signaling lymphocytic activation molecule F7 (SLAMF7) (elotuzumab) have become available for patients with multiple myeloma in the same year. Specifically, phase 3 clinical trials of combination therapies incorporating daratumumab or elotuzumab indicate both efficacy and a very favorable toxicity profile. These therapeutic monoclonal antibodies for multiple myeloma can kill target cells via antibody-dependent cell-mediated cytotoxicity, complement-dependent cytotoxicity, and antibody-dependent phagocytosis, as well as by direct blockade of signaling cascades. In addition, their immunomodulatory effects may simultaneously inhibit the immunosuppressive bone marrow microenvironment and restore the key function of immune effector cells. In this review, we focus on monoclonal antibodies that have shown clinical efficacy or promising preclinical anti-multiple myeloma activities that warrant further clinical development. We summarize mechanisms that account for the in vitro and in vivo anti-myeloma effects of these monoclonal antibodies, as well as relevant preclinical and clinical results. Monoclonal antibody-based immunotherapies have already and will continue to transform the treatment landscape in multiple myeloma.

Effect of pomalidomide on relapsed/refractory multiple myeloma: a systematic review and meta-analysis

In this work, we aim to further analyze the effect of pomalidomide for relapsed and/or refractory multiple myeloma (RRMM). A systematic literature search of PubMed, MEDLINE and EMBASE was conducted on September 20, 2016. Pooled effect size (ES) with corresponding 95% confidence intervals (CIs) were calculated using random-effects model. STATA software (version 12.0; Stata Corporation; College Station, TX, USA) was employed to do all statistical analyses. A total of 8 studies were included for analysis. The combined results demonstrated that the pooled proportion of overall response rate (ORR) was 0.35 (95% CI 0.27 to 0.43, P=0.000), and the pooled proportion of complete response rate (CRR) was 0.02 (95% CI 0.01 to 0.03, P=0.541). Pomalidomide was generally well tolerated by patients reported in the studies. Further studies would be required to conduct more prospective randomized controlled trials (RCTs) with larger samples to assess the proper place of pomalidomide as single agent or combined with other agents for RRMM.

Safety and efficacy of daratumumab in Japanese patients with relapsed or refractory multiple myeloma: a multicenter, phase 1, dose-escalation study

Safety, efficacy, and pharmacokinetics (PK) of daratumumab as a monotherapy were investigated in Japanese patients with relapsed/refractory multiple myeloma (MM). This multicenter, dose-escalation study included patients (age ≥20 years) with ≥2 prior therapies. Daratumumab was administered intravenously: 8 mg/kg (n = 4) and 16 mg/kg (n = 5). The primary endpoint was safety. Secondary endpoints included objective response, overall response rate (ORR), progression-free survival (PFS), PK, and immunogenicity. Daratumumab was well-tolerated. Eight patients experienced Grade ≥3 adverse event (AE). Four serious AEs were observed in three patients; no AEs leading to death. Infusion-related reactions occurred in four (44%) patients and were Grade 1 or 2. Mean (SD) cumulative dose of daratumumab was 132.3 (108.5) mg/kg. Median duration of follow-up was 10.5 months (range 2.3, 16.4) for 8 mg/kg cohort and 9.9 months (range 1.7, 13.2) for 16 mg/kg cohort. The ORR (44%) comprised 1 and 3 partial responses in 8 and 16 mg/kg cohorts, respectively. The median PFS was 6 months for 8 mg/kg cohort, 9.5 months for 16 mg/kg cohort. Daratumumab serum exposure was increased with increasing dose. Antibodies against daratumumab were not observed. Daratumumab was safe and well-tolerated in Japanese patients with relapsed /refractory MM.

Lenalidomide, Bortezomib, and Dexamethasone with Transplantation for Myeloma

BACKGROUND

High-dose chemotherapy plus autologous stem-cell transplantation has been the standard treatment for newly diagnosed multiple myeloma in adults up to 65 years of age. However, promising data on the use of combination therapy with lenalidomide, bortezomib, and dexamethasone (RVD) in this population have raised questions about the role and timing of transplantation.

METHODS

We randomly assigned 700 patients with multiple myeloma to receive induction therapy with three cycles of RVD and then consolidation therapy with either five additional cycles of RVD (350 patients) or high-dose melphalan plus stem-cell transplantation followed by two additional cycles of RVD (350 patients). Patients in both groups received maintenance therapy with lenalidomide for 1 year. The primary end point was progression-free survival.

RESULTS

Median progression-free survival was significantly longer in the group that underwent transplantation than in the group that received RVD alone (50 months vs. 36 months; adjusted hazard ratio for disease progression or death, 0.65; P<0.001). This benefit was observed across all patient subgroups, including those stratified according to International Staging System stage and cytogenetic risk. The percentage of patients with a complete response was higher in the transplantation group than in the RVD-alone group (59% vs. 48%, P=0.03), as was the percentage of patients in whom minimal residual disease was not detected (79% vs. 65%, P<0.001). Overall survival at 4 years did not differ significantly between the transplantation group and the RVD-alone group (81% and 82%, respectively). The rate of grade 3 or 4 neutropenia was significantly higher in the transplantation group than in the RVD-alone group (92% vs. 47%), as were the rates of grade 3 or 4 gastrointestinal disorders (28% vs. 7%) and infections (20% vs. 9%). No significant between-group differences were observed in the rates of treatment-related deaths, second primary cancers, thromboembolic events, and peripheral neuropathy.

CONCLUSIONS

Among adults with multiple myeloma, RVD therapy plus transplantation was associated with significantly longer progression-free survival than RVD therapy alone, but overall survival did not differ significantly between the two approaches. (Supported by Celgene and others; IFM 2009 Study ClinicalTrials.gov number, NCT01191060 .).

Low-dose lenalidomide and dexamethasone combination treatment in elderly patients with relapsed and refractory multiple myeloma

OBJECTIVE

This study investigated the efficacy and safety of low-dose lenalidomide combined with dexamethasone in elderly patients with relapsed and refractory multiple myeloma (MM).

METHODS

Thirty-two elderly patients with refractory and recurrent MM (median age: 64 years) were treated with low-dose lenalidomide (LD-R) combined with dexamethasone (D). LD-R (10 mg/d) was administered orally for 21 days and D (40 mg/d) was administered twice a day on days 1-4, 9-12, and 17-20. The treatment lasted 2-8 28-day cycles.

RESULTS

After two cycles, the complete, very good partial, and partial remission rates were 12.5% (4/32), 25.0% (8/32), and 34.4% (11/32), respectively. The overall response rate was 71.9% (23/32). After a 24-month follow-up, 23 patients responded to therapy, three were in complete remission, four were stable, and 16 exhibited disease progression. In addition, median time-to-progression was 13 months. Observed side effects were hypodynamia, gastrointestinal reaction, peripheral neuritis, and mild hypocytosis.

CONCLUSION

Low-dose lenalidomide in combination with dexamethasone is an effective and safe treatment for relapsed and refractory MM in elderly patients.

New monoclonal antibodies on the horizon in multiple myeloma

Across all cancers, monoclonal antibodies have emerged as a potential strategy for cancer therapy. Monoclonal antibodies target antigens expressed on the surface of cancer cells and accessory cells. This targeted approach uses the host's immune system to promote the killing of cancer cells. Multiple myeloma (MM) is the second most common hematologic malignancy that remains incurable in the majority of patients. The treatment of MM has evolved dramatically over the past decade and continues to evolve with the approval of four new drugs in 2015. Most recently the United States Food and Drug Administration (US FDA) approved two monoclonal antibodies for the treatment of this disease. Monoclonal antibodies are generally well-tolerated and offer a novel method of action for treated relapsed and refractory disease and are now being studied in the upfront setting. In this article, we review the evidence for the existing approved monoclonal antibodies and discuss promising targeted therapies and innovative strategies for the treatment of MM.

Panobinostat Plus Bortezomib Versus Lenalidomide in Patients with Relapsed and/or Refractory Multiple Myeloma: A Matching-Adjusted Indirect Treatment Comparison of Survival Outcomes using Patient-level Data

BACKGROUND

In the UK, the standard of care for patients with multiple myeloma who received ≥2 prior treatments is lenalidomide plus dexamethasone (LEN + DEX) and pomalidomide plus DEX (POM + DEX) (in Wales only). Recently, panobinostat plus bortezomib and DEX (PAN + BTZ + DEX) was licensed in this setting. The current study assessed the progression-free survival (PFS) and overall survival (OS) outcomes with PAN + BTZ + DEX versus LEN + DEX (primary comparator) and POM + DEX (exploratory comparator).

METHODS

Since an anchor-based indirect treatment comparison was not feasible, the matching-adjusted indirect treatment comparison approach was used. To compare the survival outcomes, patient-level data were generated for the comparators utilizing published Kaplan-Meier survival estimates. The use of approximated patient-level data and matched data for PAN + BTZ + DEX allowed the use of Cox proportional hazards models and the assessment of the proportional hazards assumption. In cases where there was evidence that the proportional hazards assumption was violated, time-dependent hazard ratios (HRs) were estimated. Median and mean values for PFS and OS were predicted.

RESULTS

For both PFS and OS, the proportional hazards assumption was not satisfied, therefore time-dependent HRs were estimated. Using time-dependent HRs, the mean PFS was estimated to be 11.83 months for PAN + BTZ + DEX and 10.96 months for LEN + DEX. The corresponding mean OS estimates were 30.73 and 27.76 months, respectively. Comparisons with POM + DEX were affected by large uncertainty and did not allow making robust inferences.

CONCLUSIONS

To our knowledge, this is the first study that combined matching-adjusted indirect treatment comparison with time-dependent HRs to address changing patterns in the HR. The results suggest that treatment with PAN + BTZ + DEX and LEN + DEX are associated with similar mean PFS and OS in the third-line treatment setting of multiple myeloma.

Phase 2 study of tabalumab, a human anti-B-cell activating factor antibody, with bortezomib and dexamethasone in patients with previously treated multiple myeloma

In this double-blind, Phase 2 study, 220 patients with relapsed/refractory multiple myeloma were randomly assigned 1:1:1 to receive placebo (N = 72), tabalumab 100 mg (N = 74), or tabalumab 300 mg (N = 74), each in combination with dexamethasone 20 mg and subcutaneous bortezomib 1·3 mg/m² on a 21-day cycle. No significant intergroup differences were observed among primary (median progression-free survival [mPFS]) or secondary efficacy outcomes. The mPFS was 6·6, 7·5 and 7·6 months for the tabalumab 100, 300 mg and placebo groups, respectively (tabalumab 100 mg vs. placebo Hazard ratio (HR) [95% confidence interval (CI)] = 1·13 [0·80-1·59], P = 0·480; tabalumab 300 mg vs. placebo HR [95% CI] = 1·03 [0·72-1·45], P = 0·884). The most commonly-reported treatment-emergent adverse events were thrombocytopenia (37%), fatigue (37%), diarrhoea (35%) and constipation (32%). Across treatments, patients with low baseline BAFF (also termed TNFSF13B) expression (n = 162) had significantly longer mPFS than those with high BAFF expression (n = 55), using the 75th percentile cut-off point (mPFS [95% CI] = 8·3 [7·0-9·3] months vs. 5·8 [3·7-6·6] months; HR [95% CI] = 1·59 [1·11-2·29], P = 0·015). Although generally well tolerated, PFS was not improved during treatment with tabalumab compared to placebo. A higher dose of 300 mg tabalumab did not improve efficacy compared to the 100 mg dose. Nonetheless, BAFF appears to have some prognostic value in patients with multiple myeloma.

Association between complete response and outcomes in transplant-eligible myeloma patients in the era of novel agents

OBJECTIVES

Achieving complete response (CR) has been linked to improved progression-free (PFS) and overall (OS) survival in myeloma. A meta-analysis was conducted to investigate whether this holds true in the era of novel agents (bortezomib, lenalidomide, thalidomide).

METHODS

A total of 24 studies in newly diagnosed patients undergoing autologous stem cell transplantation (ASCT) that reported associations between responses and long-term outcomes (PFS/OS rates post-ASCT by response, or hazard ratios with 95% confidence intervals from Cox models) were identified and analyzed.

RESULTS

Achievement of CR vs. <CR post-ASCT reduced risk of progression/death by 38% [risk ratio (RR): 0.62, P < 0.0001]; risk of death was 41% lower (RR: 0.59, P < 0.0001). Subgroup meta-analyses showed significant PFS risk reduction with CR post-ASCT with novel (RR: 0.32, P < 0.006) and non-novel (RR: 0.72, P < 0.0001) agents, and corresponding OS risk reduction with novel (RR: 0.33, P = 0.0013) and non-novel (RR: 0.64, P < 0.0001) agents. Risk reduction was greater with novel vs. non-novel agents (PFS: P = 0.047; OS: P = 0.058).

CONCLUSIONS

Achieving CR during first-line therapy remains important in the novel-agent era; magnitude of association between achieving CR and outcomes appears higher for CR obtained using novel vs. non-novel agents.

Targeting heparanase overcomes chemoresistance and diminishes relapse in myeloma

In most myeloma patients, even after several rounds of intensive therapy, drug resistant tumor cells survive and proliferate aggressively leading to relapse. In the present study, gene expression profiling of tumor cells isolated from myeloma patients after sequential rounds of chemotherapy, revealed for the first time that heparanase, a potent promoter of myeloma growth and progression, was elevated in myeloma cells that survived therapy. Based on this clinical data, we hypothesized that heparanase was involved in myeloma resistance to drug therapy. In several survival and viability assays, elevated heparanase expression promoted resistance of myeloma tumor cells to chemotherapy. Mechanistically, this enhanced survival was due to heparanase-mediated ERK signaling. Importantly, use of the heparanase inhibitor Roneparstat in combination with chemotherapy clearly diminished the growth of disseminated myeloma tumors in vivo. Moreover, use of Roneparstat either during or after chemotherapy diminished regrowth of myeloma tumors in vivo following therapy. These results provide compelling evidence that heparanase is a promising, novel target for overcoming myeloma resistance to therapy and that targeting heparanase has the potential to prevent relapse in myeloma and possibly other cancers.

Panobinostat: A Review in Relapsed or Refractory Multiple Myeloma

Oral panobinostat (Farydak®), a potent nonselective histone deacetylase inhibitor, is approved in several countries for use in combination with bortezomib and dexamethasone in patients with multiple myeloma (MM) [USA] or relapsed and/or refractory MM (EU) who have received at least two prior treatment regimens, including bortezomib and an immunomodulatory drug (IMiD). In a pivotal phase III trial (PANORAMA 1) in patients with relapsed or relapsed and refractory MM who had received one to three previous lines of therapy, progression-free survival (PFS) was significantly prolonged with panobinostat plus bortezomib and dexamethasone compared with placebo plus bortezomib and dexamethasone. The significantly favourable effect of panobinostat- versus placebo-based treatment on PFS was also observed in a subgroup analysis of patients who had previously received an IMiD, bortezomib plus an IMiD, or at least two lines of treatment including bortezomib and an IMiD. Panobinostat plus bortezomib and dexamethasone had a generally manageable tolerability profile, with the most frequent grade 3-4 adverse events being myelosuppression, diarrhoea, asthenia or fatigue, peripheral neuropathy and pneumonia. Thus, panobinostat, in combination with bortezomib and dexamethasone, is a useful addition to the available treatment options for patients with relapsed or refractory MM.

Deacetylase inhibitors as a novel modality in the treatment of multiple myeloma

Deacetylase enzymes remove acetyl groups from histone and nonhistone proteins. Dysregulation of deacetylase activity is a hallmark of malignancy, including multiple myeloma (MM). Deacetylase inhibitors (DACi) cause epigenetic modification and inhibition of the aggresome pathway, resulting in death of MM cells. Panobinostat, a pan-DACi, has shown significant clinical benefit and is the first DACi approved for the treatment of MM. It is approved for use in combination with bortezomib and dexamethasone for the treatment of patients with relapsed or relapsed and refractory MM who have received ≥2 prior regimens including bortezomib and an immunomodulatory drug. Ricolinostat and ACY-241, which selectively inhibit HDAC6 and the aggresome pathway, are currently being studied in combination with dexamethasone and bortezomib or an immunomodulatory drug for the treatment of relapsed and refractory MM. In this review, we discuss the data from key clinical trials investigating deacetylase inhibitors as novel treatment options for MM.

Heparanase: From basic research to therapeutic applications in cancer and inflammation

Heparanase, the sole heparan sulfate degrading endoglycosidase, regulates multiple biological activities that enhance tumor growth, angiogenesis and metastasis. Heparanase expression is enhanced in almost all cancers examined including various carcinomas, sarcomas and hematological malignancies. Numerous clinical association studies have consistently demonstrated that upregulation of heparanase expression correlates with increased tumor size, tumor angiogenesis, enhanced metastasis and poor prognosis. In contrast, knockdown of heparanase or treatments of tumor-bearing mice with heparanase-inhibiting compounds, markedly attenuate tumor progression further underscoring the potential of anti-heparanase therapy for multiple types of cancer. Heparanase neutralizing monoclonal antibodies block myeloma and lymphoma tumor growth and dissemination; this is attributable to a combined effect on the tumor cells and/or cells of the tumor microenvironment. In fact, much of the impact of heparanase on tumor progression is related to its function in mediating tumor-host crosstalk, priming the tumor microenvironment to better support tumor growth, metastasis and chemoresistance. The repertoire of the physio-pathological activities of heparanase is expanding. Specifically, heparanase regulates gene expression, activates cells of the innate immune system, promotes the formation of exosomes and autophagosomes, and stimulates signal transduction pathways via enzymatic and non-enzymatic activities. These effects dynamically impact multiple regulatory pathways that together drive inflammatory responses, tumor survival, growth, dissemination and drug resistance; but in the same time, may fulfill some normal functions associated, for example, with vesicular traffic, lysosomal-based secretion, stress response, and heparan sulfate turnover. Heparanase is upregulated in response to chemotherapy in cancer patients and the surviving cells acquire chemoresistance, attributed, at least in part, to autophagy. Consequently, heparanase inhibitors used in tandem with chemotherapeutic drugs overcome initial chemoresistance, providing a strong rationale for applying anti-heparanase therapy in combination with conventional anti-cancer drugs. Heparin-like compounds that inhibit heparanase activity are being evaluated in clinical trials for various types of cancer. Heparanase neutralizing monoclonal antibodies are being evaluated in pre-clinical studies, and heparanase-inhibiting small molecules are being developed based on the recently resolved crystal structure of the heparanase protein. Collectively, the emerging premise is that heparanase expressed by tumor cells, innate immune cells, activated endothelial cells as well as other cells of the tumor microenvironment is a master regulator of the aggressive phenotype of cancer, an important contributor to the poor outcome of cancer patients and a prime target for therapy.

Phase 1/2 study of daratumumab, lenalidomide, and dexamethasone for relapsed multiple myeloma

Daratumumab, a human CD38 immunoglobulin G1 kappa (IgG1κ) monoclonal antibody, has activity as monotherapy in multiple myeloma (MM). This phase 1/2 study investigated daratumumab plus lenalidomide/dexamethasone in refractory and relapsed/refractory MM. Part 1 (dose escalation) evaluated 4 daratumumab doses plus lenalidomide (25 mg/day orally on days 1-21 of each cycle) and dexamethasone (40 mg/week). Part 2 (dose expansion) evaluated daratumumab at the recommended phase 2 dose (RP2D) plus lenalidomide/dexamethasone. Safety, efficacy, pharmacokinetics, immunogenicity, and accelerated daratumumab infusions were studied. In part 1 (13 patients), no dose-limiting toxicities were observed, and 16 mg/kg was selected as the R2PD. In part 2 (32 patients), median time since diagnosis was 3.2 years, with a median of 2 prior therapies (range, 1-3 prior therapies), including proteasome inhibitors (91%), alkylating agents (91%), autologous stem cell transplantation (78%), thalidomide (44%), and lenalidomide (34%); 22% of patients were refractory to the last line of therapy. Grade 3 to 4 adverse events (≥5%) included neutropenia, thrombocytopenia, and anemia. In part 2, infusion-related reactions (IRRs) occurred in 18 patients (56%); most were grade ≤2 (grade 3, 6.3%). IRRs predominantly occurred during first infusions and were more common during accelerated infusions. In part 2 (median follow-up of 15.6 months), overall response rate was 81%, with 8 stringent complete responses (25%), 3 complete responses (9%), and 9 very good partial responses (28%). Eighteen-month progression-free and overall survival rates were 72% (95% confidence interval, 51.7-85.0) and 90% (95% confidence interval, 73.1-96.8), respectively. Daratumumab plus lenalidomide/dexamethasone resulted in rapid, deep, durable responses. The combination was well tolerated and consistent with the safety profiles observed with lenalidomide/dexamethasone or daratumumab monotherapy. This trial was registered at www.clinicaltrials.gov as #NCT01615029.

Efficacy and Safety of Panobinostat in Relapsed or/and Refractory Multiple Myeloma: Meta Analyses of Clinical Trials and Systematic Review

During the past decades, many novel agents have improved response and survival of patients with multiple myeloma. Nevertheless, it remains challenging when they suffer relapsing. Thus, novel therapeutic agents are needed. We aimed to assess the efficacy and safety of a novel agent panobinostat for patients with relapsed or/and refractory MM. A systematic literature review identified studies for clinical trials about panobinostat in patients with relapsed or/and refractory MM. We searched studies published between January 2000 and December 2015 in Pubmed, Ovid, EBSCO and the Cochrane library. Random-effect pooled estimates were calculated for overall response rate and rates of common adverse effects. The results showed 11 clinical trials including 700 patients with relapsed or/and refractory MM treated with panobinostat were identified. The ORR varied between 0.08 and 0.67. Pooled analyses showed the results that the ORR was 0.45 (95% CI: 0.31–0.59, I² = 90.5%, P = 0.000) for panobinostat combined with any other kind of drugs. The most common Grade3/4 adverse effects were thrombocytopenia, neutropenia, lymphopenia, anemia, diarrhea, fatigue, nausea and so on. In conclusion, based on our analyses, the regimen of panobinostat combining with other agents seems to be well tolerated and efficacious in patients with relapsed or/and refractory MM.

Clinical developments in the treatment of relapsed or relapsed and refractory multiple myeloma: impact of panobinostat, the first-in-class histone deacetylase inhibitor

BACKGROUND

Panobinostat is a new agent for the treatment of relapsed and refractory multiple myeloma (rrMM) as part of a combination regimen. This article presents an overview of the mechanism of action, pharmacokinetics, safety, efficacy, patient care strategies, and role of the agent in treating rrMM patients.

RESULTS

Panobinostat belongs to the class of drugs known as histone deacetylase inhibitors, and has high activity against Class I, II, and IV nonhistone deacetylases and histone deacetylases. It represents the first of its class to receive approval for use in MM, and received priority review and orphan drug status in both US and Europe, when used in combination with bortezomib and dexamethasone in the treatment of rrMM. Approval of panobinostat was based on subgroup analysis of Phase III data obtained in the PANORAMA trial program for evaluation of the combination of panobinostat, bortezomib, and dexamethasone. Additional clinical trials have continued to explore optimal dosing regimens and novel combination regimens to further clarify the optimal role of panobinostat in the arsenal of drugs for rrMM. Panobinostat has shown a manageable safety profile characterized primarily by hematologic toxicities (thrombocytopenia, neutropenia, lymphopenia, and anemia), gastrointestinal toxicities, notably diarrhea and nausea, as well as fatigue/asthenia, electrolyte abnormalities, and less commonly cardiac toxicities.

CONCLUSION

Panobinostat represents an important addition to the treatment armamentarium for patients with rrMM, and studies are underway evaluating its optimal dosing strategy and role in combination with other drugs used to treat this patient population.

Multiple myeloma in the marrow: pathogenesis and treatments

Multiple myeloma (MM) is a B cell malignancy resulting in osteolytic lesions and fractures. In the disease state, bone healing is limited owing to increased osteoclastic and decreased osteoblastic activity, as well as an MM-induced forward-feedback cycle where bone-embedded growth factors further enhance tumor progression as bone is resorbed. Recent work on somatic mutation in MM tumors has provided insight into cytogenetic changes associated with this disease; the initiating driver mutations causing MM are diverse because of the complexity and multitude of mutations inherent in MM tumor cells. This manuscript provides an overview of MM pathogenesis by summarizing cytogenic changes related to oncogenes and tumor suppressors associated with MM, reviewing risk factors, and describing the disease progression from monoclonal gammopathy of undetermined significance to overt MM. It also highlights the importance of the bone marrow microenvironment (BMM) in the establishment and progression of MM, as well as associated MM-induced bone disease, and the relationship of the bone marrow to current and future therapeutics. This review highlights why understanding the basic biology of the healthy and diseased BMM is crucial in the quest for better treatments and work toward a cure for genetically diverse diseases such as MM.

Targeting CD38 with Daratumumab Monotherapy in Multiple Myeloma

BACKGROUND

Multiple myeloma cells uniformly overexpress CD38. We studied daratumumab, a CD38-targeting, human IgG1κ monoclonal antibody, in a phase 1-2 trial involving patients with relapsed myeloma or relapsed myeloma that was refractory to two or more prior lines of therapy.

METHODS

In part 1, the dose-escalation phase, we administered daratumumab at doses of 0.005 to 24 mg per kilogram of body weight. In part 2, the dose-expansion phase, 30 patients received 8 mg per kilogram of daratumumab and 42 received 16 mg per kilogram, administered once weekly (8 doses), twice monthly (8 doses), and monthly for up to 24 months. End points included safety, efficacy, and pharmacokinetics.

RESULTS

No maximum tolerated dose was identified in part 1. In part 2, the median time since diagnosis was 5.7 years. Patients had received a median of four prior treatments; 79% of the patients had disease that was refractory to the last therapy received (64% had disease refractory to proteasome inhibitors and immunomodulatory drugs and 64% had disease refractory to bortezomib and lenalidomide), and 76% had received autologous stem-cell transplants. Infusion-related reactions in part 2 were mild (71% of patients had an event of any grade, and 1% had an event of grade 3), with no dose-dependent adverse events. The most common adverse events of grade 3 or 4 (in ≥ 5% of patients) were pneumonia and thrombocytopenia. The overall response rate was 36% in the cohort that received 16 mg per kilogram (15 patients had a partial response or better, including 2 with a complete response and 2 with a very good partial response) and 10% in the cohort that received 8 mg per kilogram (3 had a partial response). In the cohort that received 16 mg per kilogram, the median progression-free survival was 5.6 months (95% confidence interval [CI], 4.2 to 8.1), and 65% (95% CI, 28 to 86) of the patients who had a response did not have progression at 12 months.

CONCLUSIONS

Daratumumab monotherapy had a favorable safety profile and encouraging efficacy in patients with heavily pretreated and refractory myeloma. (Funded by Janssen Research and Development and Genmab; ClinicalTrials.gov number, NCT00574288.).

Targeting B-cell maturation antigen in multiple myeloma

Novel effective immunotherapies are needed for patients with multiple myeloma (MM), since disease recurrence remains a major obstacle. B-cell maturation antigen (BCMA), a cell surface protein universally expressed on malignant plasma cells , has emerged as a very selective antigen to be targeted in novel treatments for MM. We here first review BCMA-related biology, and then highlight the recent clinical development of a novel afucosylated anti-BCMA monoclonal antibody conjugated with monomethyl auristatin F via noncleavable linker (GSK2857916). Chimeric antigen receptor-expressing T cells targeting BCMA may also induce specific and durable anti-MM responses by patients' own effector cells. Clinical trials testing these two approaches (NCT02064387, NCT02215967) are currently ongoing in relapsed and refractory MM patients.

Panobinostat for the Treatment of Multiple Myeloma

Panobinostat is a potent oral deacetylase inhibitor that alters gene expression through epigenetic mechanisms and inhibits protein degradation. It was recently approved by the FDA and EMA for use in combination with bortezomib and dexamethasone in patients with multiple myeloma who have received ≥2 prior regimens, including bortezomib and an immunomodulatory drug. Panobinostat was approved based on results from the phase III PANORAMA 1 trial in patients with relapsed or relapsed and refractory multiple myeloma, which showed that panobinostat plus bortezomib and dexamethasone significantly extended progression-free survival (median, 12.0 months) compared with placebo plus bortezomib and dexamethasone (median, 8.1 months; P < 0.0001). Additional ongoing trials are evaluating panobinostat in combination with other partners in the relapsed/refractory and newly diagnosed treatment settings. This review focuses on panobinostat and its mechanism of action, pharmacokinetics, and clinical data in the treatment of relapsed or relapsed and refractory multiple myeloma.

The investigational proteasome inhibitor ixazomib for the treatment of multiple myeloma

ABSTRACT 

Ixazomib is an investigational, reversible 20S proteasome inhibitor. It is the first oral proteasome inhibitor under clinical investigation in multiple myeloma (MM). Under physiological conditions, the stable citrate ester drug substance, ixazomib citrate (MLN9708), rapidly hydrolyzes to the biologically active boronic acid, ixazomib (MLN2238). Preclinical studies have demonstrated antitumor activity in MM cell lines and xenograft models. In Phase I/II clinical studies ixazomib has had generally manageable toxicities, with limited peripheral neuropathy observed to date. Preliminary data from these studies indicate ixazomib is active as a single agent in relapsed/refractory MM and as part of combination regimens in newly diagnosed patients. Phase III studies in combination with lenalidomide–dexamethasone are ongoing.