Therapy In Multiple Myeloma Patients Research Articles

Comparison of Outcomes and Utilization of Therapy in Multiple Myeloma Patients in the USA and Alberta, Canada

Background: Multiple myeloma (MM) is a common global hematologic malignancy, contributing to substantial morbidity and mortality amongst diagnosed patients. Novel agents - bortezomib (Btz) and lenalidomide (Len) have changed dramatically over the past 20 years and have contributed to improvements in survival and long term outcomes for MM patients. Research has shown that there are differences in how MM is treated globally. We sought to evaluate the differences in outcomes and therapies received amongst patients treated in Alberta (AB), Canada, and in the United States (USA). Methods: Adult patients with multiple myeloma over the age of 65, diagnosed between 2007 and 2013, were identified. Data sources used for AB was the CA National Ambulatory Care Reporting System (NACRS), Discharge Abstracts Database (DAD), and CT records from AB Health Services. For the USA we used the SEER-Medicare database; MM diagnosis was extracted using a previously published algorithm. We extracted demographic data, novel agent utilization in the first year, comorbidities, and survival. Kaplan-Meier analysis was used to determine survival. Results: Patients meeting study criteria included 4,330 MM patients in the USA and 793 patients with MM in AB. The median age at diagnosis in the USA and AB was 76.6 and 75 years, respectively. Median Charlson Comorbidity index in the USA and AB was 1, and 0, respectively. With respect to frontline therapies, both AB and USA had increasing utilization of Btz and Len from 2007-2013 (Figure), with Btz use more common in AB, while Len use was more common in the US. The proportion of all patients who did not receive any therapy in the first year of diagnosis fell dramatically from 2007 to 2013 in both AB (from 86% to 25%) and the USA (from 56% to 40%). Receipt of autologous stem cell transplant was uncommon in this older cohort, in only 3.2% of MM patients in AB and 4% of patients in the US. Similar proportions of patients in the USA and AB received radiotherapy in the first year (19% US, 25% AB). Median overall survival was improved in AB at 2.8 years, (95% CI 2.6-3.2 yrs), compared with the USA, 2.2 yrs (95% CI 2.1 - 2.30, as was 5 year survival - 30% in the USA, compared with 34% in AB. Conclusions: In this cross-country comparison of MM patients in the USA and AB both treated in a single-payer health care system - AB Health Services and Medicare - novel agents are a common treatment in the first year of diagnosis. We demonstrate similar uptake of novel agents Btz and Len over 2007-2013, however, Btz utilization was higher in AB from 2011-2013, while Len was more often used in the USA from 2011-2013. Median overall survival was better in AB (2.8 years) compared with USA (2.3 years), as was long term survival at 5 years. The differences in utilization of therapy and survival are possibly related to variability in healthcare delivery systems, burden of comorbidities in these populations, and approval of anti-MM therapy over time, and require further study to better understand reasons for differential outcomes. Figure Disclosures Cowan: Sanofi: Consultancy; Cellectar: Consultancy; Bristol Myers Squibb: Research Funding; Janssen: Consultancy, Research Funding; Abbvie: Research Funding. Ramsey:AstraZeneca: Other: Personal Fees.

Synergistic Effect of Venetoclax for Antibody Dependent Cell Cytotoxicity By Daratumumab

The prognosis of multiple myeloma (MM) has improved following the development of new drugs such as proteasome inhibitors and immunomodulatory drugs, but many patients are refractory to existing therapy. Venetoclax is a selective, orally bioavailable inhibitor of BCL2, showing efficacy in not only the monotherapy but also as the combination therapy of MM patients, especially those harboring t (11;14). Herein, we aimed to evaluate the synergistic cytotoxicity of venetoclax and daratumumab in vitro using KMS12PE and SKMM1 cell lines. The cells were treated with venetoclax and daratumumab targeting BCL2 and CD38, respectively. Flow cytometry showed that both cells were good therapeutic targets for daratumumab with the positive ratio of CD38 being 100% and 75.7% in KMS12PE and SKMM1, respectively (Figure 1). Western blotting showed that BCL2 expression was strongly detected in KMS12PE but barely in SKMM1 cells (Figure 2). Furthermore, using the WST1 assay for evaluating the cytotoxicity of venetoclax, we observed that KMS12PE cells were sensitive to 100 nM of venetoclax while SKMM1 cells were not sensitive up to 10 uM, which corresponded with the expression levels of BCL2 in both the cells (Figure 3). Then, the cytotoxicities of venetoclax, daratumumab, and their combination, were compared using flow cytometry with annexin V detection; the results indicated that the combination therapy exhibited higher cytotoxicity than the monotherapies. This experiment was repeated 3 times, and the average value with standard deviation (SD) is shown in Figure 4. Collectively, these results indicate that the antibody-dependent cell-mediated cytotoxicity was enhanced in KMS12PE cells harboring t (11;14) with high BCL2 expression, suggesting that the combination of venetoclax and daratumumab displays a synergistic effect in treating MM harboring t (11;14) with high BCL2 expression. Our data support the results of a recent phase І/II clinical trial for MM (Bahlis N et al. Blood 2019;925-925.), wherein 24 patients with R/R MM were treated with a combination therapy of venetoclax, daratumumab and dexamethasone, and the efficacy and safety of the therapy were evaluated. The ORR of the patients with t (11;14) treated with the combination therapy was 92%, which demonstrated the significant efficacy of the combination treatment. Thus, while the efficacy of the combination therapy of venetoclax and daratumumab has already been confirmed in a clinical trial, our data further shows the synergistic cytotoxic effect of venetoclax and daratumumab in vitro. Our in vitro analysis could, therefore, serve useful in the estimation of the effective dosage of each drug for the treatment of MM using clinical samples. Disclosures Hanamura: DAIICHI SANKYO COMPANY, LIMITED: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Ono Pharmaceutical Co., Ltd.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Janssen Pharmaceutical K.K.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi K.K.: Research Funding; Takeda Pharmaceutical Company Limited: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Kyowa Kirin Co., Ltd.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Eisai Co., Ltd.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; NIPPON SHINYAKU CO.,LTD.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer Japan Inc.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie Inc.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Otsuka Pharmaceutical Co., Ltd.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; SHIONOGI Co., Ltd.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Mundipharma K.K.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; CSL Behring: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; MSD K.K.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis Pharma K.K.: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Ueda:Chugai Pharmaceutical Co., Ltd.: Research Funding; Kyowa Kirin Co., Ltd.: Research Funding; Ono Pharmaceutical Co., Ltd.: Research Funding. Takami:Yamada Bee Farm: Research Funding; Fukuyuukai: Research Funding; Novartis Pharma K.K.: Honoraria; Kyowa Kirin Co., Ltd.: Research Funding; Pfizer Japan Inc.: Research Funding; Chugai Pharmaceutical Co., Ltd.: Research Funding; Astellas Pharma Inc.: Research Funding. OffLabel Disclosure: The combination therapy of daratumumab with venetoclax for multiple myeloma.

Efficacy of Subsequent Therapies in Multiple Myeloma Patients after Progression on a BCMA Targeting Therapy: A Single-Center Experience

Background: Targeting B-cell maturation antigen (BCMA) with antibody-drug conjugates (ADCs), bispecific antibodies, or chimeric antigen receptor t-cells (CAR-Ts) has proven safe and effective in recent clinical trials, but relapses remain common. As most patients treated with BCMA targeting therapies are refractory to conventional anti-myeloma therapies, management of these patients poses unique challenges once they progress, with no data available to guide subsequent therapies. Methods: We performed a retrospective chart review of all relapsed refractory multiple myeloma (RRMM) patients at our institution who progressed while on or after a BCMA targeting therapy and were treated with subsequent therapies. We evaluated the best response achieved and overall survival (OS) measured from progression on BCMA targeting therapies. Kaplan Meier methods were used to estimate OS curves and landmarks between classes of BCMA targeting therapy received (ADC, bispecific antibody or CAR-T), and by type of subsequent therapy. Results: At a median follow up of 6 months, a total of 47 patients were treated with a BMCA targeting therapy. Of those, a total of 21 (44.7%) patients have progressed, with 18 (38.3%) receiving another therapy. Twelve-month overall survival of the patients who received a subsequent treatment was 51.1% (figure 1a), but varied considerably based on the class of BCMA therapy they received (figure 1b). Patients who progressed after a BCMA CAR-T had the best OS (N =2, 6 mo OS: 100%, 12 mo OS: Of the 18 patients who progressed and were treated with subsequent therapies, 7 (38.9%) received 2 lines of therapy, 5 (27.8%) received 3 lines of therapy, and 1 patient (5.6%) received 5 lines of therapy. In the first relapse, 4 (22.2%) patients received infusional chemotherapy with CAR-D PACE or CAR-DCEP, 4 (22.2%) received the combination of elotuzumab, pomalidomide, and dexamethasone (Elo-Pd; one of which was first treated with CAR-DCEP), 3 (16.7%) received selinexor based regimens. The best response seen after first-line post BCMA treatment was a partial response (PR) in 5 (27.8% of patients), whereas 8 (61.5%) patients who received second-line treatment post-BCMA therapy had a PR or better, including 3 (23.1%) who had a very good partial response (VGPR). In the third line post-BCMA, 1 (16.7%) had a VGPR, while 1 (16.7%) had stable disease as their best response. The use of Elo or Dara after anti-BCMA progression seemed to correlate with improved OS (see figure 1c below). While all these patients were Elo naïve, the majority (94.4%) were previously Dara exposed. Conclusions: Our data demonstrate that many RRMM patients who progress on BCMA targeting therapies still derive benefit from subsequent treatment. Early evidence from our experience suggests a survival advantage with monoclonal antibody-based therapies even in patients who had previously been exposed to these agents-suggesting a possible resensitization with BCMA directed therapy. Although our dataset is a single-center experience, to our knowledge it represents the first report of post-BCMA exposed management of RRMM and provides valuable insight into the treatment of this challenging and ever-expanding population. Disclosures Paul: Bristol-Myers Squibb: Other: Stock Ownership (prior employee); Amgen: Consultancy, Speakers Bureau; Regeneron: Membership on an entity's Board of Directors or advisory committees. Bhutani:BMS: Other: Clinical trial funding to institute, Speakers Bureau; Takeda: Other: Clinical trial funding to institute, Speakers Bureau; Prothena: Other: Clinical Trial Funding to Institute; Amgen: Speakers Bureau; MedImmune: Other: Clinical Trial Funding to Institute; Sanofi Genzyme: Consultancy; Janssen: Other: Clinical Trial Funding to Institute. Voorhees:Adaptive Biotechnologies: Other: Personal fees; Bristol-Myers Squibb: Other: Personal fees; Celgene: Other: Personal fees; Janssen: Other: Personal fees; Novartis: Other: Personal fees; Oncopeptides: Other: Personal fees; TeneoBio: Other: Personal fees; Levine Cancer Institute, Atrium Health: Current Employment. Usmani:Celgene: Other; Janssen: Consultancy, Honoraria, Other: Speaking Fees, Research Funding; SkylineDX: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Merck: Consultancy, Research Funding; Incyte: Research Funding; Pharmacyclics: Research Funding; Array Biopharma: Research Funding; GSK: Consultancy, Research Funding; Takeda: Consultancy, Honoraria, Other: Speaking Fees, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy; BMS, Celgene: Consultancy, Honoraria, Other: Speaking Fees, Research Funding; Amgen: Consultancy, Honoraria, Other: Speaking Fees, Research Funding. Atrash:BMS, Jansen oncology, Sanofi: Speakers Bureau; Takeda, Amgen, Karyopharm, BMS, Sanofi, Cellactar, Janssen and Celgene: Honoraria; Amgen, GSK, Karyopharm.: Research Funding.

B-Cell/Mixed Phenotype Acute Leukemia Following Lenalidomide Maintenance For Multiple Myeloma: A Study Of Two Cases

Abstract Introduction/Objective The incidence of patients with multiple myeloma (MM) followed by hematologic malignancies as second primary malignancy is around 0.8 – 3.1%. The majority of cases are myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), however, acute lymphoblastic or mixed phenotype leukemia can be rarely observed. Methods A retrospective chart review was performed for patients diagnosed with acute lymphoblastic or mixed phenotype leukemia from January 2009 through February 2020. Two patients were identified and the corresponding clinical data were reviewed. Results Case 1 was a 74-year old male diagnosed with pre-B ALL 5 years after an IgG Lambda MM. His MM therapy included Bortezomib-based chemotherapy followed by Lenalidomide maintenance. Pre-B diagnosis was confirmed on a pelvic lesion biopsy with sheets of intermediate sized cells (CD45+, PAX5+, CD34+, CD43+, CD10+, BCL6+ and BCL2+). The patient had 4 cycles of HyperCVAD chemotherapy, followed by Blinatumomab and Inotuzumab treatment. Unfortunately, the patient was referred to hospice 2 years after the diagnosis of ALL. Case 2 was a 69-year old male diagnosed with mixed phenotype acute leukemia 8 years after an lgA Lambda MM with del 13q and Trisomy 11. The patient was treated with Bortezomib-based chemotherapy followed by autologous hematopoietic stem cell transplantation (auto-HSCT) and Lenalidomide maintenance. Bone marrow biopsy showed around 79% blasts (CD34+, PAX-5+, CD79a+ and MPO+). Flow cytometry from bone marrow showed 90% precursor B cells, however MPO was negative. Furthermore, a DNTM3A p.T835M missense variant (25-30% fraction) was identified by next generation sequencing (NGS). The patient was scheduled for Hyper-CVAD chemotherapy. Conclusion Lenalidomide maintenance following auto-HSCT is considered a standard therapy for MM patients. Recent studies indicate that Lenalidomide maintenance is associated with an increased risk of second primary hematologic malignancies. Although AML and MDS are more commonly seen, ALL and rarely mixed phenotype leukemias can occur.

The Value of Serum MicroRNA Expression Signature in Predicting Refractoriness to Bortezomib-Based Therapy in Multiple Myeloma Patients.

Simple SummaryThe proteasome inhibitor bortezomib is currently commonly used for the treatment of multiple myeloma (MM). MicroRNAs (miRNAs) are small non-coding RNAs that play a crucial role in messenger RNA silencing and post-transcriptional regulation of gene expression. In MM, the expression of several miRNAs is markedly dysregulated suggesting their role in MM pathogenesis and drug resistance. The aim of our study was to assess miRNA expression patterns in the serum of MM patients treated with bortezomib. We have identified 21 serum miRNAs differentially expressed in patients refractory to bortezomib-based chemotherapy. A miRNAs-based prediction model was developed to assess the probability of refractoriness to bortezomib. Our findings, indicating the differential expression of miRNAs between bortezomib-refractory and bortezomib-sensitive patients, suggest that these circulating miRNAs may play an important role in personalized treatment of MM patients.Bortezomib is the first-in-class proteasome inhibitor, commonly used in the treatment of multiple myeloma (MM). The mechanisms underlying acquired bortezomib resistance in MM are poorly understood. Several cell-free miRNAs have been found to be aberrantly regulated in MM patients. The aim of this pilot study was to identify a blood-based miRNA signature that predicts bortezomib-based therapy efficacy in MM patients. Thirty MM patients treated with bortezomib-based regimens were studied, including 19 with refractory disease and 11 who were bortezomib sensitive. Serum miRNA expression patterns were identified with miRCURY LNA miRNA miRNome PCR Panels I+II (Exiqon/Qiagen). Univariate analysis found a total of 21 miRNAs to be differentially expressed in patients with MM according to bortezomib sensitivity. Multivariate logistic regression was created and allowed us to discriminate refractory from sensitive patients with a very high AUC of 0.95 (95%CI: 0.84–1.00); sensitivity, specificity and accuracy were estimated as 0.95, 0.91, and 0.93. The model used expression of 3 miRNAs: miR-215-5p, miR-181a-5p and miR-376c-3p. This study is the first to demonstrate that serum expression of several miRNAs differs between patients who are bortezomib refractory and those who are sensitive which may prove useful in studies aimed at overcoming drug resistance in MM treatment.

Novel Approaches to Improve Myeloma Cell Killing by Monoclonal Antibodies.

The monoclonal antibodies (mAbs) have significantly changed the treatment of multiple myeloma (MM) patients. However, despite their introduction, MM remains an incurable disease. The mAbs currently used for MM treatment were developed with different mechanisms of action able to target antigens, such as cluster of differentiation 38 (CD38) and SLAM family member 7 (SLAMF7) expressed by both, MM cells and the immune microenvironment cells. In this review, we focused on the mechanisms of action of the main mAbs approved for the therapy of MM, and on the possible novel approaches to improve MM cell killing by mAbs. Actually, the combination of anti-CD38 or anti-SLAMF7 mAbs with the immunomodulatory drugs significantly improved the clinical effect in MM patients. On the other hand, pre-clinical evidence indicates that different approaches may increase the efficacy of mAbs. The use of trans-retinoic acid, the cyclophosphamide or the combination of anti-CD47 and anti-CD137 mAbs have given the rationale to design these types of combinations therapies in MM patients in the future. In conclusion, a better understanding of the mechanism of action of the mAbs will allow us to develop novel therapeutic approaches to improve their response rate and to overcome their resistance in MM patients.

Triplet versus doublet therapy in multiple myeloma patients over 75 years.

e20519 Background: Clinical trials in multiple myeloma (MM) typically enroll patients that are younger and less frail while 33% patients are over the age of 75. Advanced age/frailty is associated with worse prognosis, partly due to poor tolerability of therapy. Compared to doublets, triplets improve progression-free and overall survival (PFS and OS), but these outcomes are not well studied in older patients. Here, we compare doublet and triplet therapy in newly diagnosed MM patients over 75. Methods: The MMRF’s CoMMpass trial is an international, longitudinal, observational study capturing disease progression and response to treatment. Using the MMRF database, we compared doublet versus triplet therapy in patients over 75. Primary outcome was PFS while secondary outcomes included OS, quality of life (QoL) and fatigue. QoL was assessed using EORTC QLQ-C30 questionnaire and fatigue was captured by the MM eCRF survey. Results: 146 patients were eligible for analysis. Median age was 80 years. 27 (18%) were ISS 1, 38 (26%) were ISS 2, and 59 (40%) were ISS 3. Amongst doublets (n = 62), 48% received Bortezomib/Dexamethasone while 48% received Lenalidomide/Dexamethasone. Amongst triplets (n = 71), 35% received both proteasome inhibitors (PI) and immunomodulatory drugs (IMIDs), whereas 58% received PI-based therapy with no IMID. Mean PFS for doublets was 467 days and for triplets was 608 days, with difference of 141 days (p = 0.0663). Mean OS for doublets was 757 days and for triplets was 920 days. Difference of 163 days was not statistically significant (p = 0.1784). In doublets, QoL remained at a median of 50% from baseline to 5 years. In triplets, QoL improved from a median 58% to 83% from baseline to 5 years. With respect to fatigue, levels remained unchanged from baseline to 5 years in doublets (43 to 44%) and dropped from 37% to 29% in triplets. Conclusions: There is a trend towards improved PFS, as well as an improvement in QoL and fatigue in MM patients over 75 that are treated with triplets as compared to those treated with doublets. Limitations include lack of randomization and selection bias.

Clinical outcomes and prognostic factors in patients with multiple myeloma in South Tyrol: a retrospective single-center analysis.

High-dose chemotherapy followed by autologous stem cell transplantation (HD-ASCT) as well as the introduction of novel agents (NA) significantly improved survival for patients with multiple myeloma (MM). A total of 150 unselected newly diagnosed MM patients treated at our institution from 1998 to 2017 were retrospectively analyzed. Median age at diagnosis was 69years (range 33-93years) with a median follow-up of 48.6months. The median overall survival (OS) for the entire cohort was 60.7months (range 0.3-280.1). Patients who received frontline HD-ASCT (p < 0.01) or NA-based first-line treatment (p = 0.043) had a significantly better OS. According to the revised Myeloma Comorbidity Index (R-MCI), patients were defined as fit (36.5%), intermediate-fit (44.5%), or frail (19%) with a significant difference in OS between these categories (p < 0.01). Multivariate analysis revealed R-MCI as an independent prognostic factor for OS (p < 0.01). Presence of subclinical amyloid deposits (A+) was detected in 18 out of 66 patients (27.3%) and significantly correlated with a serum free light chain (sFLC) ratio ≥ 100 (p = 0.01) and bone marrow plasma cell infiltration > 60% (p = 0.04). Furthermore, patients with A+ had significantly worse OS compared with their counterparts (p = 0.048). Our results corroborate the efficacy of both early HD-ASCT and the use of new agents as initial therapy of MM patients in "real-world" daily clinical practice. The R-MCI is an easily applicable tool to stratify MM patients and may support treatment decisions. The prognostic value of subclinical amyloid deposition should be validated within prospective studies.

Blockade of HSP70 by VER-155008 synergistically enhances bortezomib-induced cytotoxicity in multiple myeloma

Proteasome inhibitor bortezomib is one of the most effective drugs currently available for the treatment of multiple myeloma (MM). However, the intrinsic and acquired resistance to bortezomib can limit its effectiveness. The activation of heat shock response has been characterized as a potential resistance mechanism protecting MM cells from bortezomib-induced cell death. In this study, in response to bortezomib therapy, we discovered that HSP70 is one of the most substantially upregulated heat shock proteins. In order to further explore approaches to sensitizing bortezomib-based treatment for MM, we investigated whether targeting HSP70 using a specific inhibitor VER-155008 combined with bortezomib could overcome the acquired resistance in MM. We found that HSP70 inhibitor VER-155008 alone significantly decreased MM cell viability. Moreover, the combination of VER-155008 and bortezomib synergistically induced MM cell apoptosis markedly in vitro. Notably, the combined treatment was found to increase the cleavage of PARP, an early marker of chemotherapy-induced apoptosis. Importantly, the reduction of anti-apoptotic Bcl-2 family member Bcl-2, Bcl-xL, and Mcl-1 and the induction of pro-apoptotic Bcl-2 family member BH3-only protein NOXA and Bim were confirmed to be tightly associated with the synergism. Finally, the ER stress marker CHOP (CCAAT-enhancer binding protein homologous protein), which can cause transcriptional activation of genes involved in cell apoptosis, was markedly induced by both VER-155008 and bortezomib. Taken together, our finding of a strong synergistic interaction between VER-155008 and bortezomib may support for combination therapy in MM patients in the future.

Dynamics of tumor-specific cfDNA in response to therapy in multiple myeloma patients.

ObjectivesProgress in multiple myeloma treatment allows patients to achieve deeper responses, for which the assessment of minimal residual disease (MRD) is critical. Typically, bone marrow samples are used for this purpose; however, this approach is site‐limited. Liquid biopsy represents a minimally invasive and more comprehensive technique that is not site‐limited, but equally challenging.MethodsWhile majority of current data comes from short‐term studies, we present a long‐term study on blood‐based MRD monitoring using tumor‐specific cell‐free DNA detection by ASO‐qPCR. One hundred and twelve patients were enrolled into the study, but long‐term sampling and analysis were feasible only in 45 patients.ResultsWe found a significant correlation of quantity of tumor‐specific cell‐free DNA levels with clinically meaningful events [induction therapy (P = .004); ASCT (P = .012)]. Moreover, length of cfDNA fragments is associated with better treatment response of patients.ConclusionsThese results support the concept of tumor‐specific cell‐free DNA as a prognostic marker.

Flow Cytometry and Pharmacokinetic Studies

Biography Vellalore Kakkanaiah, PhD serves as the director of the flow cytometry group, which is part of the Biomarker Laboratories at PPD Richmond, VA. His team is focused on the development of flow cytometry methods to support drug development. Recently, his team developed a simple whole blood assay to study the cellular kinetics of CAR-T cells after adoptive cell therapy in multiple myeloma patients. Prior to joining PPD, Dr Kakkanaiah was a senior scientist at SurroMed, Inc. where he developed micro volume laser scanning cytometry assays. He earned a doctorate in immunology from Madurai Kamaraj University in India and then served as a postdoctoral fellow at Virginia Tech. His postdoctoral training involved the first identification of mature CD4-CD8 T cells by flow cytometry from the thymus of an autoimmune mouse model. He was also a fellow of the Arthritis Foundation at the UNC-Chapel Hill. Vellalore N Kakkanaiah speaks to the International Journal of Pharmacokinetics about his experience in developing flow cytometry assays for measuring cellular kinetics in adoptive cell therapies. Flow cytometry is new to bioanalysis and is being used for measuring the cellular kinetics of infused cells from adoptive cell therapy. Here, he discusses the challenges in developing flow cytometry methods for monitoring the infused CAR-T cells.

Personalized Ubiquitination Signatures for Predicting Response to Proteasome Inhibitor-Based Therapy of MM Patients

Introduction Proteasome inhibition has emerged as an important therapeutic strategy in multiple myeloma (MM) and its first-in-class agent, bortezomib, has become a major player in MM treatment. Bortezomib reversibly inhibits the proteasome, inducing an accumulation of ubiquitinated proteins in MM cells, which results in endoplasmic reticulum stress-related apoptosis. However, up to 30% of patients (pts) have been shown to fail bortezomib-based induction and the underlying mechanisms remain poorly understood. As protein degradation by the proteasome, is reliant on protein ubiquitination, uncovering the ubiquitination profile of bone marrow mononuclear cells (BM-MNC) of MM pts, may offer putative biomarkers for predicting the response to treatment and in the future shed new light on disease pathophysiology. In collaboration with PTM Biosciences, we investigated ubiquitination patterns in BM-MNC samples obtained from MM pts treated with bortezomib-based induction. We hypothesized that ubiquitination patterns at diagnosis would differ between responders vs non-responders and would serve as a platform for identifying potential new therapeutic targets involved in induction of primary resistance. Methods BM-MNC samples, collected prior to therapy from 31 NDMM pts, treated with Velcade (bortezomib)-Cyclophosphamide-Dexamethasone (VCD) or VD, were analyzed. Response to treatment was determined after 4-6 cycles of treatment (employing the IMWG criteria), unless progressed earlier. Functional total cells extract that preserve the cellular enzymatic activity were prepared from each sample and applied to protein microarrays containing ~9000 known proteins (ProtoArray®, Thermo Fisher). Following the exposure of the protein array surface to the sample, enzymes from the sample modified the thousands of proteins spotted on the array, to generate a patient-specific signatures of ubiquitination (Experimental Biology and Medicine 2016; 0: 1-8). The ubiquitination level of every protein was quantified, data was normalized using the quantile normalization method and sorted by descending order for each sample. The ranking position of a protein at each sample within one group was compared to its ranking positions on the other group samples. The proteins differing in their ranking level (p-value ≤ 0.005) between groups were selected. Results Thirty-one BM-MNC samples obtained from MM pts prior VCD (n=27) or VD (n=4) induction, were tested. The cohort included 16 responding patient that achieved at least PR and 15 non-responding pts that obtained SD or less (Table 1). PTM analysis initially revealed 241 proteins that were considered as differentially modified between the 2 groups, mostly in the non-responders (153 vs 88). Ubiquitination of a specific protein was determined as "highly discriminating", if shown to be discriminating in at least 50% of the rounds. We identified 44 classifier proteins; 11 that were highly ubiquitinated in the responders and 33 in the non-responders. These 44 proteins were defined as "highly discriminating", providing a unique PTM signature for responders vs non-responders (Figure 1). Among the 44 proteins, 14 (31.8%) were previously suggested to serve as biomarkers in other cancers and 6 other proteins (13.6 %) were found to be related to the ubiquitin/ubiquitin-like or proteasome machinery. At least 3 of these proteins (USP28, SQSTM1 &amp; PSME1) are known to be related to MM and responsiveness to bortezomib treatment. Further validation of 6 of these targets, confirmed their expression in BM-MNC samples in an independent assay. Prospective clinical validation is required to examine the specificity and sensitivity of the identified biomarkers. Conclusions Here we provide a proof-of-concept for the ability of ubiquitination profiling of BM-MNC samples to identify putative biomarkers for predicting response to bortezomib-based therapy. Among the proteins identified some were associated with response to bortezomib treatment and other novel candidates require further prospective validation. Algorithm training, validation cohort and investigation of the predictive value of this approach in MM pts treated with other therapeutic regimens are underway. Our study provides the first example in clinical samples, highlighting the potential significance of this approach in the clinic and offers a novel strategy for proteomics-based personalized medicine. Disclosures Tsubery: PTM Biosciences: Employment. Gali:PTM Biosciences: Employment. Gali:PTM Biosciences: Employment. Sela:PTM Biosciences: Consultancy. Merbl:PTM Biosciences: Consultancy, Equity Ownership. Cohen:VBL Therapeutics Â: Employment; Madison Â: Consultancy; Takeda Â: Consultancy; Neopharm Â: Consultancy; Amgen Â: Consultancy, Research Funding; Janssen Â: Consultancy.

A Prospective Phase II of Daratumumab in Previously Treated Systemic Light-Chain (AL) Amyloidosis: Updated Results

Daratumumab (DARA) is a high-affinity human monoclonal antibody that specifically recognizes CD38. It has emerged as a breakthrough targeted therapy for multiple myeloma patients (pts). Monoclonal plasma cells in AL amyloidosis (AL) express CD38. We report here updated results of a prospective multi-center, phase 2 study of DARA in AL (NCT02816476).

Daratumumab is a safe and effective rescue therapy for multiple myeloma patients who relapse after allo-HSCT

This study was supported in part by the Spanish grant of Instituto de Salud Carlos III (PI16/01485) and FEDER European Union.

Proteolysis targeting chimeric molecules as therapy for multiple myeloma: efficacy, biomarker and drug combinations.

Proteolysis targeting chimeric molecule ARV 825 causes ubiquitination of bromodomains resulting in their efficient degradation by proteasome activity. Bromodomain degradation down-regulates MYC transcription contributing to growth inhibition of various human cancers. We examined the therapeutic potential of ARV 825 against multiple myeloma (MM) cells both in vitro and in vivo. In a dose-dependent manner, ARV 825 inhibited proliferation of 13 human MM cell lines and three fresh patient samples, and was associated with cell cycle arrest and apoptosis. ARV 825 rapidly and efficiently degraded BRD 2 and BRD 4. Sensitivity of MM cells to ARV 825 was positively correlated with cereblon levels. RNA sequencing analysis showed important genes such as CCR1, RGS, MYB and MYC were down-regulated by ARV 825. A total of 170 small molecule inhibitors were screened for synergy with ARV 825. Combination of ARV 825 with inhibitor of either dual PI3K/mTOR, CRM1, VEGFR, PDGFRα/b, FLT3, IGF-1R, protein kinase C, CBP-EP300 or JAK1/2 showed synergistic activity. Importantly, ARV 825 significantly inhibited the growth of MM xenografts and improved mice survival. Taken together, our results, in conjunction with recently published findings, provide a rationale for investigating the efficacy of ARV 825 for MM, use of cereblon as a biomarker for therapy of MM patients, and the combination of ARV 825 with small molecule inhibitors to improve the outcome of MM patients.

Percutaneous Exposures of volunteers to polychromatic light (480-3400 nm) trigger systemic mechanism of the human myeloma cells growth delay without any effect on bortezomib cytotoxicity in vitro

Polychromatic light is actively used in medicine. However, its oncological safety and effect against cytotoxic therapy remains poorly studied. Multiple myeloma (MM) develops in the bone marrow and therefore malignant plasma cells are inaccessible to direct exposure to light. The aim of our work was to study the influence of polychromatic visible and infra-red light (pVIS + pIR) on growth and sensitivity of the myeloma cells to the cytotoxic effect of drug bortezomib (BTZ) through systemic mechanism. We explored the effect of volunteers blood sera after their 4-daily irradiations with pVIS + pIR light (480-3400 nm) on growth and viability of the human myeloma RPMI 8226 cells in the presence of BTZ at its application in 2 modes: short-term (1 h, 300 nM) and long-term ( 96 h, 5 nM). Viability and proliferative activity of cells was evaluated by MTT assay. It was found that photomodified blood sera delayed growth of myeloma RPMI 8226 cells (by 25 % in 48 h and 23 % in 96 h) but had no effect on spontaneous and mitogen-induced proliferation of autologous peripheral blood T- and B-lymphocytes. We also revealed that pVIS + pIR did not change RPMI 8226 cells sensitivity to BTZ. The results suggest the systemic mechanism of polychromatic light and argue in favor of its oncological safety during/after BTZ therapy of MM patients without effect on the drug cytotoxicity.

Potential Therapeutic Roles of Exosomes in Multiple Myeloma: A Systematic Review.

Multiple myeloma (MM) is the second most prevalent hematological malignancy. In spite of the remarkable progress in understanding the biology and therapy of MM, curing this disease remains difficult, which calls for more effective treatment strategies. As vital communicators between different cells, exosomes have been verified to be crucial to cancer diagnosis, treatment, and prognosis. Exosomes in MM patients show a different expression profile compared with those in healthy individuals. In this review, we summarize potential therapy roles exosomes may play in MM. The specific expression of certain components in exosomes may provide therapeutic targets. Moreover, tumor-derived exosomes and their modified products can be developed into vaccines for anti-tumor immunity. In addition, the natural nano structure of exosomes makes them excellent carriers for drug delivery. Thus, a more rigorous investigation into exosomes will pave the way for novel tumor therapies in MM patients.

A Single Autologous Stem Cell Transplant (ASCT) Followed By Two Years of Post-Transplant Therapy in Recently Diagnosed Elderly Multiple Myeloma (MM) Patients. Safety and Response Results from the Prospective Phase II Trial (NCT01849783)

Introduction : Melphalan 200mg/m2 has been the standard conditioning regimen for ASCT for multiple myeloma. Novel agents in combination with high dose melphan are being evaluated in clinical trials to improve outcomes. We previously reported results of early ASCT ( < 12 months from diagnosis) using VDT (Bortezomib, Thalidomide, Dexamethasone) plus Melphalan 200mg/m2 conditioning chemotherapy followed by combination maintenance therapy in younger MM patients (Age <65). This current prospective study evaluates the tolerance, safety and efficacy of early ASCT and maintenance therapy in MM patients who are ≥65 of age.Methods and patients: A total of 41 eligible patients with newly diagnosed multiple myeloma age ≥ 65 were prospectively enrolled in the IRB approved phase II trial beginning in June 2013. After an induction chemotherapy and stem cell collection, ASCT was performed with a preparative chemotherapy consisting of VDT-Melphalan 200mg/m2. The patients were considered to have high risk cytogenetics if they had 17p deletion, t(14;16), amp 1q, or t(4;14) by FISH on CD-138 sorted plasma cells. After engraftment and recovery, patients were started on maintenance therapy for 2 years. Planned regimen for the first year was a combination of VDT as 28 day cycles and year 2 therapy consisted of bortezomib, cyclophosphamide and dexamethasone( VCD) as 28 day cycles. Alternate regimens were used in case of toxicities. Primary end points include PFS, frequency of severe toxicities, ICU admissions, and percentage of patients able to complete the full course of maintenance. Responses were evaluated according to IMWG consensus criteria and adverse events were recorded according to CTCAE v 4.03.Results: 37 of the 41 patients enrolled received single ASCT between 2013 to 2016 of which 35 patients went to receive triple maintenance therapy and were included in this analysis. Median age was 68 (range: 65 to 75y). 12 (59%) and 15(40%) had standard risk and high risk cytogenetics by FISH, respectively. Median follow up was 27 months (3 months - 5 years). Major non-hematologic toxicities ≥ grade 3 were related to infections (25%), diarrhea (16%) and mucositis (11%). Median time to ANC and platelet engraftment was 11 and 17 days, respectively. There was one death within day 100 related to candida sepsis. Only 2 patients were re-hospitalized within 100 days but none required ICU admission. Median time to start post-transplant therapy was 73 days (range: 47 to 185 days). Best responses noted prior to initiation of maintenance were 17 sCR(47.2%), 3CR(8%), 10 VGPR(27%) and 6 PR(17%). 18 patients completed 2 years of maintenance therapy thus far and responses at the time of this analysis include sCR in 16 and CR in 2 patients. A total of 3 patients died during maintenance phase due to progressive disease. Median PFS and OS were not reached and 3 year PFS and OS were around 82 and 90%, respectively.Conclusions:This is the first trial to prospectively evaluate the safety and efficacy of early ASCT in elderly MM patients using a novel agent conditioning regimen followed by an intensive 2 year maintenance therapy. These results from the median follow up of 27 months indicate that the regimen is safe and tolerated without any increased mortality, and results in higher rates of deep and sustained responses. Major non hematologic toxicities included infections and GI related. No increased hospitalizations or ICU admissions were noted. Further follow up will determine the long term effects of the combination maintenance regimen, disease responses and survival in this group of elderly MM patients. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Bortezomib-Based Consolidation/Maintenance Therapy for Multiple Myeloma: A Meta-Analysis of Randomized Controlled Trials

Background: Bortezomib is a proteasome inhibitor that can lead to cell-cycle arrest and apoptosis. Bortezomib-based regimens are widely used as induction therapy of multiple myeloma (MM). Unlike lenalidomide (an immunomodulatory drug), the role of bortezomib in the consolidation and maintenance therapy of multiple myeloma is less clear. This study aims to examine the efficacy and safety of bortezomib-based regimens as consolidation/maintenance therapy in MM patients following induction therapy with or without autologous stem cell transplantation (ASCT).Methods: PubMed, ASH, and ASCO databases were searched for randomized controlled trials (RTC) of bortezomib-based regimens (either single-agent or combination) as consolidation/maintenance therapy for MM patients through July 2018. Study endpoints included overall survival (OS), progression-free survival (PFS), and adverse events (AE). Pooled hazard ratios (HR) for survival outcomes and relative risks (RR) for dichotomous data with 95% confidence interval (CI) were calculated with a random effect model using MedCalc (MedCalc Software, Ostend, Belgium). For studies that did not report HRs for survival outcomes but provided graphical survival curves, the log HRs and variances were estimated based on the method by Parmar et al (Stat Med 1998; 17: 2815-2834). Heterogeneity was assessed using the I2 statistic of inconsistency, with statistically significant heterogeneity defined as I2 > 50% or p-value < 0.1.Results: Eight randomized controlled trials (7 phase III, 1 phase II; 2 were published in a single article) were identified. Bortezomib-based regimens were administered as consolidation treatment in 5 RTCs and maintenance therapy in 3 RTCs, following induction therapy +/- ASCT. A total of 2439 patients were included: 1154 patients received bortezomib-based regimens, and 1285 patients received non-bortezomib-based regimens or observation. Two RCTs (1 for consolidation, 1 for maintenance) did not provide HRs, which were estimated as described as above. Pooled data from the 8 RCTs showed that bortezomib-based consolidation/maintenance therapy improved progression-free survival (HR 0.71, 95% CI 0.64-0.79, P < 0.001; I2 = 6.61%) and overall survival (HR 0.80, 95% CI 0.68-0.94, P = 0.005; I2 = 0%) compared to observation or regimens without bortezomib. When the 2 RCTs that did not report HRs were excluded from the meta-analysis, it did not alter the favorable outcome of bortezomib-based consolidation/maintenance therapy: PFS (HR 0.70, 95% CI 0.60-0.82, P < 0.001; I2 = 40.54%) and OS (HR 0.76, 95% CI 0.64-0.91, P = 0.002; I2 = 0%). The PFS benefit was maintained in a subgroup analysis by the setting of treatment (consolidation, HR 0.73, 95% CI 0.63-0.85, P < 0.001; I2 = 0%, maintenance, HR 0.70, 95% CI 0.56-0.0.86, P = 0.001; I2 = 55.63%). Bortezomib-based therapy prolonged OS in the maintenance setting (HR 0.71, 95% CI 0.58-0.86, P < 0.001; I2 = 0%) but not in the consolidation setting (HR 1.01, 95% CI 0.77-1.33, P = 0.935; I2 = 0%). Regarding safety, bortezomib-based consolidation/maintenance therapy significantly increased the risk of grade 3 or 4 peripheral sensory neuropathy and neuralgia (RR 2.09, 95% CI 1.11-3.95, p = 0.022; I2 = 52.64%) compared to observation or regimens without bortezomib. There was a trend toward increased rates of grade 3 or 4 thrombocytopenia (RR 1.54, 95% CI 0.95-2.52, p = 0.08; I2 = 21.67%), GI symptoms (RR 2.54, 95% CI 0.63-10.25, p = 0.19; I2 = 76.72%), vascular events (RR 1.90, 95% CI 0.80-4.53, p = 0.15; I2 = 0.00%), and fatigue (RR 2.10, 95% CI 0.83-5.30, p = 0.12; I2 = 0.00%) with bortezomib-based consolidation/maintenance, but these did not reach statistical significance.Conclusions: Bortezomib-based consolidation/maintenance significantly improves PFS and OS in MM patients following induction therapy +/- ASCT. The OS benefit appears to be limited to the maintenance setting based on a subgroup analysis. Bortezomib-based regimen increases the risk of grade 3 or 4 peripheral sensory neuropathy and neuralgia. [Display omitted] DisclosuresBachanova:Gamida Cell: Research Funding; GT Biopharma: Research Funding; Kite Pharma: Membership on an entity's Board of Directors or advisory committees.

Multiple Myeloma Treatment Is Associated with Enhanced Platelet Reactivity

Multiple myeloma (MM) is associated with elevated levels of thrombotic disease. Poor mobility due to bone disease and older age are contributory factors but a satisfactory molecular or cellular explanation for this has not been established. Furthermore, the treatment of newly-diagnosed or relapsed MM patients with immunomodulatory drugs increases thrombosis risk. In this study, we therefore sought to determine whether platelet function and/or haemostasis is altered during the clinical progression from the benign monoclonal gammopathy of underdetermined significance (MGUS) to the smouldering myeloma (SM, untreated) state, and to establish the impact of lenalidomide therapy in MM patients on platelet reactivity.Patients (MGUS (N=10), SM (N=10) MM (N=4), healthy volunteer/control (N=10)) were recruited at the myeloma clinics at the Royal Berkshire and Oxford University Hospital Trusts. Single blood samples were obtained from controls, MGUS and smoldering myeloma participants. For patients undergoing therapy (lenalidomide, dexamethasone and anti-coagulant or anti-platelet therapy), samples were taken at predose Cy1, Cy1 D14, Cy1 D28 (a week free from lenalidomide administration), and Cy4 D14. All blood samples were taken less than 12 hours from Lenalidomide dosing, and analysis performed within 4 hours. High throughput platelet function analysis was performed on platelet-rich plasma and washed platelets to measure platelet aggregation, secretion and fibrinogen binding in response collagen, collagen-related peptide (a collagen receptor GPVI-selective ligand), ADP, thrombin receptor activatory peptide (TRAP), the thromboxane mimetic U46619 and epinephrine, and full concentration-response profiles obtained for each. The levels of key platelet receptors including GPVI, CD61, CD41b, CD36 and CD31, were also measured by flow cytometry and remained unaltered between groups. In comparison with control samples, platelet functional responses (maximal response, maximal gain and EC50) from MGUS and smoldering myeloma patients were unaltered (EC50: ADP 1µM, collagen-related peptide (CRP-XL) 0.1µg/ml, U46619 1µM, TRAP 1.6µM, epinephrine 1.3µM). Similarly circulating levels of platelet-bound fibrinogen and P-selectin exposure were unaltered (control: 709±194 AU, MGUS: 581±129 AU, SM: 655±148 AU 9 (Mean±SD)). In MM patients during therapy, the levels of these platelet responses (aggregation, fibrinogen binding and P-selectin exposure - a marker for a-granule secretion) were increased 2-4 fold. In most patients this was notable at week 2 and had declined approximately 50% by week 4 of cycle 1 but remained above predose levels, and remained elevated to a similar level in drug cycle 4.The study of further patients (including Bortezomib treated patients as controls) will be required in order to validate these findings which suggest that (1) baseline platelet function is not substantially compromised in MM and SM, (2) lenalidomide and other immunomodulatory drugs may be able to modulate platelets in patients causing increased platelet reactivity, and (3) effects noted are lenalidomide-dependent and not related to inflammatory state secondary to disease response. The effects of exposure of platelets to lenalidomide in vitro in the presence or absence of dexamethasone and a proteasome inhibitor are being tested to explore potential direct effects of the drugs on circulating platelets. Results from these experiments will also be presented. DisclosuresGibbins:Celgene Corporation: Research Funding. Rana:Celgene Corporation: Research Funding. Khan:Celgene Corporation: Research Funding. Shapiro:Freeline Therapeutics Ltd: Consultancy. Grech:Novartis: Other: sponsorship for scientific meetings. Ramasamy:Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.