Identification of a Maturation Plasma Cell Index through a Highly Sensitive Droplet Digital PCR Assay Gene Expression Signature Validation in Newly Diagnosed Multiple Myeloma Patients

DNA microarrays and RNA-based sequencing approaches are considered important discovery tools in clinical medicine. However, cross-platform reproducibility studies undertaken so far have highlighted that microarrays are not able to accurately measure gene expression, particularly when they are expressed at low levels. Here, we consider the employment of a digital PCR assay (ddPCR) to validate a gene signature previously identified by gene expression profile. This signature included ten Hedgehog (HH) pathways' genes able to stratify multiple myeloma (MM) patients according to their self-renewal status. Results show that the designed assay is able to validate gene expression data, both in a retrospective as well as in a prospective cohort. In addition, the plasma cells' differentiation status determined by ddPCR was further confirmed by other techniques, such as flow cytometry, allowing the identification of patients with immature plasma cells' phenotype (i.e., expressing CD19+/CD81+ markers) upregulating HH genes, as compared to others, whose plasma cells lose the expression of these markers and were more differentiated. To our knowledge, this is the first technical report of gene expression data validation by ddPCR instead of classical qPCR. This approach permitted the identification of a Maturation Index through the integration of molecular and phenotypic data, able to possibly define upfront the differentiation status of MM patients that would be clinically relevant in the future.

The ALLgorithMM: How to define the hemodilution of bone marrow samples in lymphoproliferative diseases

Introduction

Minimal residual disease (MRD) is commonly assessed in bone marrow (BM) aspirate. However, sample quality can impair the MRD measurement, leading to underestimated residual cells and to false negative results. To define a reliable and reproducible method for the assessment of BM hemodilution, several flow cytometry (FC) strategies for hemodilution evaluation have been compared.

Methods

For each BM sample, cells populations with a well-known distribution in BM and peripheral blood - e.g., mast cells (MC), immature (IG) and mature granulocytes (N) – have been studied by FC and quantified alongside the BM differential count.

Results

The frequencies of cells’ populations were correlated to the IG/N ratio, highlighting a mild correlation with MCs and erythroblasts (R=0.25 and R=0.38 respectively, with p-value=0.0006 and 0.0000052), whereas no significant correlation was found with B or T-cells. The mild correlation between IG/N, erythroblasts and MCs supported the combined use of these parameters to evaluate BM hemodilution, hence the optimization of the ALLgorithMM. Once validated, the ALLgorithMM was employed to evaluate the dilution status of BM samples in the context of MRD assessment. Overall, we found that 32% of FC and 52% of Next Generation Sequencing (NGS) analyses were MRD negative in samples resulted hemodiluted (HD) or at least mildly hemodiluted (mHD).

Conclusions

The high frequency of MRD-negative results in both HD and mHD samples implies the presence of possible false negative MRD measurements, impairing the correct assessment of patients’ response to therapy and highlighs the importance to evaluate BM hemodilution.

Final analysis of the phase III non-inferiority COLUMBA study of subcutaneous versus intravenous daratumumab in patients with relapsed or refractory multiple myeloma

In the primary analysis of the phase III COLUMBA study, daratumumab by subcutaneous administration (DARA SC) demonstrated non-inferiority to intravenous administration (DARA IV) for relapsed or refractory multiple myeloma (RRMM). Here, we report the final analysis of efficacy and safety from COLUMBA after a median of 29.3 months follow-up (additional 21.8 months after the primary analysis). In total, 522 patients were randomized (DARA SC, n=263; DARA IV, n=259). With longer follow-up, DARA SC and DARA IV continued to show consistent efficacy and maximum trough daratumumab concentration as compared with the primary analysis. The overall response rate was 43.7% for DARA SC and 39.8% for DARA IV. The maximum mean (standard deviation [SD]) trough concentration (cycle 3, day 1 pre-dose) of serum DARA was 581 (SD, 315) μg/mL for DARA SC and 496 (SD, 231) μg/mL for DARA IV. Median progression-free survival was 5.6 months for DARA SC and 6.1 months for DARA IV; median overall survival was 28.2 months and 25.6 months, respectively. Grade 3/4 treatment-emergent adverse events occurred in 50.8% of patients in the DARA SC group and 52.7% in the DARA IV group; the most common (≥10%) were thrombocytopenia (DARA SC, 14.2%; DARA IV, 13.6%), anemia (13.8%; 15.1%), and neutropenia (13.1%; 7.8%). The safety profile remained consistent with the primary analysis after longer follow-up. In summary, DARA SC and DARA IV continue to demonstrate similar efficacy and safety, with a low rate of infusion-related reactions (12.7% vs. 34.5%, respectively) and shorter administration time (3-5 minutes vs. 3-7 hours) supporting DARA SC as a preferable therapeutic choice. (Clinicaltrials gov. Identifier: NCT03277105.

MPN-182 Droplet Digital PCR for Non-Invasive Detection of the KIT D816V Mutation in the Peripheral Blood of Patients With Suspected Systemic Mastocytosis

CONTEXT

Systemic mastocytosis (SM) is a rare and underdiagnosed hematologic neoplasm. Detection of the D816V KIT mutation in the bone marrow (BM) is one of the minor criteria for the diagnosis of SM and requires sensitive methods like ASO-qPCR. In patients with suspected SM, non-invasive pre-screening of peripheral blood (PB) by ASO-qPCR has been shown to detect the D816V mutation with a concordance with BM results of 92% in indolent SM (ISM) patients with skin lesions and of 66% in those without skin lesions. However, ASO-qPCR is not standardized, and commercial kits are not available. Droplet digital PCR (ddPCR) might be a valuable alternative to ASO-qPCR.

OBJECTIVE

To validate a commercially available ddPCR assay for the detection and quantitation of the KIT D816V mutation and to evaluate its potential as a non-invasive screening tool in patients with suspected SM.

METHODS

To assess specificity and calculate the limit of blank, PB samples from 30 healthy donors (HDs) were used. The limit of detection was determined by mixing KIT D816V-mutated (HMC-1.2) and unmutated (HMC-1.1) cell lines in order to mimic different allele burdens, from 50% down to 0.01%. Accuracy was investigated by analyzing, in parallel, 35 samples from patients with confirmed or suspected ISM by ASO-qPCR and ddPCR. Concordance between ddPCR results in BM and PB was assessed in 60 matched PB/BM samples. ddPCR was performed using 50 ng/µL of genomic DNA with the KIT p.D816V human mutation assay on a QX200 instrument (Bio-Rad).

RESULTS

No KIT D816V-positive events were detected in any of the HD samples. In HMC 1.2 cell dilutions, KIT D816V mutation could be detected down to 0.01% allele burden. Comparison of ddPCR and ASO-qPCR revealed very high concordance in mutation detection and quantitation. All patients positive for KIT D816V in the BM also tested positive in the PB by ddPCR. Moreover, ddPCR revealed high concordance in mutation quantitation between BM and PB, even at very low variant allele frequencies.

CONCLUSIONS

ddPCR is an attractive alternative to ASO-qPCR for KIT D816V mutation detection and quantification in SM and may reliably detect the D816V mutation non-invasively in PB in patients with suspected SM.

Drug resistance in multiple myeloma: Soldiers and weapons in the bone marrow niche

Multiple myeloma (MM) is still an incurable disease, despite considerable improvements in treatment strategies, as resistance to most currently available agents is not uncommon. In this study, data on drug resistance in MM were analyzed and led to the following conclusions: resistance occurs via intrinsic and extrinsic mechanisms, including intraclonal heterogeneity, drug efflux pumps, alterations of drug targets, the inhibition of apoptosis, increased DNA repair and interactions with the bone marrow (BM) microenvironment, cell adhesion, and the release of soluble factors. Since MM involves the BM, interactions in the MM-BM microenvironment were examined as well, with a focus on the cross-talk between BM stromal cells (BMSCs), adipocytes, osteoclasts, osteoblasts, endothelial cells, and immune cells. Given the complex mechanisms that drive MM, next-generation treatment strategies that avoid drug resistance must target both the neoplastic clone and its non-malignant environment. Possible approaches based on recent evidence include: (i) proteasome and histone deacetylases inhibitors that not only target MM but also act on BMSCs and osteoclasts; (ii) novel peptide drug conjugates that target both the MM malignant clone and angiogenesis to unleash an effective anti-MM immune response. Finally, the role of cancer stem cells in MM is unknown but given their roles in the development of solid and hematological malignancies, cancer relapse, and drug resistance, their identification and description are of paramount importance for MM management.

Association of IMWG frailty score with health-related quality of life profile of patients with relapsed refractory multiple myeloma in Italy and the UK: a GIMEMA, multicentre, cross-sectional study

BACKGROUND

The clinical management of patients with relapsed or refractory multiple myeloma is challenging and there is a paucity of tools to help clinicians make more informed decisions for the most suitable treatment options. We aimed to investigate the clinical utility of the International Myeloma Working Group (IMWG) frailty score in the setting of relapsed or refractory multiple myeloma, by examining its ability to capture different patient-reported health-related quality of life profiles.

METHODS

We did a cross-sectional analysis of a prospective observational study of patients with relapsed or refractory multiple myeloma in Italy and the UK (30 hospitals across northern, central, and southern Italy, and one hospital in London, UK). Inclusion criteria were age 18 years or older and patients who had received at least one previous line of therapy and no more than five lines. Participants were excluded if they had a psychiatric disorder or major cognitive dysfunction, or any grade 3 or higher adverse event within 2 weeks before study entry. On study initiation, physicians had to assess frailty according to the IMWG criteria, which included the Charlson Comorbidity Index, the Katz Activity of Daily Living, and the Lawton Instrumental Activities of Daily Living. Patients were asked to complete patient-reported outcome measures, including the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core30 (EORTC QLQ-C30) and its validated multiple myeloma module (QLQ-MY20). A multivariable linear regression model was used to assess the mean differences in health-related quality of life scores between frailty groups to account for key potential confounding factors.

FINDINGS

Overall, between Nov 13, 2017, and Nov 15, 2021, 415 patients with relapsed or refractory multiple myeloma, with a median age of 69·8 years (IQR 62·8-75·2) were enrolled. The median time since diagnosis was 4·4 years (IQR 2·5-7·1) and most patients (351 [85%]) had received at least two previous lines of therapy. According to the IMWG frailty score, 200 (48%) were classified as fit, 112 (27%) were classified as intermediate-fit, and 103 (25%) patients were classified as frail. Each frailty group was associated with a distinct health-related quality of life profile, with most notable differences between fit and frail patients. The largest clinically meaningful adjusted differences between fit and frail patients by the EORTC QLQ-C30 questionnaire were observed for physical functioning (Δ=-19·0 [95% CI -25·6 to -12·5; p<0·0001), fatigue (Δ=16·7 [9·7 to 23·7]; p<0·0001), insomnia (Δ=13·4 [4·1 to 22·6]; p=0·0047), and dyspnoea (Δ=12·5 [4·6 to 20·4]; p=0·0021). The most prevalent clinically important symptom in the overall population was pain; however, its prevalence varied between IMWG frailty groups at 70·9% in frail patients, 55·9% in intermediate-fit patients, and 50·5% in fit patients.

INTERPRETATION

Our findings show the clinical utility of the IMWG frailty score in the setting of relapsed or refractory multiple myeloma, in helping to distinguish between groups of patients with distinct health-related quality of life profiles. Further research is needed to examine the value of patient-reported outcome data in improving assessment of frailty in the setting of relapsed or refractory multiple myeloma.

FUNDING

Fondazione GIMEMA Franco Mandelli Onlus and Amgen.

Secondary infections worsen the outcome of COVID-19 in patients with hematological malignancies: A report from the ITA-HEMA-COV

The impact of secondary infections (SI) on COVID-19 outcome in patients with hematological malignancies (HM) is scarcely documented. To evaluate incidence, clinical characteristics, and outcome of SI, we analyzed the microbiologically documented SI in a large multicenter cohort of adult HM patients with COVID-19. Among 1741 HM patients with COVID-19, 134 (7.7%) had 185 SI, with a 1-month cumulative incidence of 5%. Median time between COVID-19 diagnosis and SI was 16 days (IQR: 5-36). Acute myeloid leukemia (AML) and lymphoma/plasma cell neoplasms (PCN) were more frequent diagnoses in SI patients compared to patients without SI (AML: 14.9% vs. 7.1%; lymphoma/PCN 71.7% vs. 65.3%). Patients with SI were older (median age 70 vs. 66 years, p = 0.002), with more comorbidities (median Charlson Comorbidity Index 5 vs. 4, p < 0.001), higher frequency of critical COVID-19 (19.5% vs. 11.5%, p = 0.046), and more frequently not in complete remission (75% vs. 64.7% p = 0.024). Blood and bronchoalveolar lavage were the main sites of isolation for SI. Etiology of infections was bacterial in 80% (n = 148) of cases, mycotic in 9.7% (n = 18) and viral in 10.3% (n = 19); polymicrobial infections were observed in 24 patients (18%). Escherichia coli represented most of Gram-negative isolates (18.9%), while coagulase-negative Staphylococci were the most frequent among Gram-positive (14.2%). The 30-day mortality of patients with SI was higher when compared to patients without SI (69% vs. 15%, p < 0.001). The occurrence of SI worsened COVID-19 outcome in HM patients. Timely diagnosis and adequate management should be considered to improve their prognosis.

Polo-like kinase-1, Aurora kinase A and WEE1 kinase are promising druggable targets in CML cells displaying BCR::ABL1-independent resistance to tyrosine kinase inhibitors

In chronic myeloid leukemia (CML), Aurora kinase A and Polo like kinase 1 (PLK1), two serine-threonine kinases involved in the maintenance of genomic stability by preserving a functional G2/M checkpoint, have been implicated in BCR::ABL1-independent resistance to the tyrosine kinase inhibitor (TKI) imatinib mesylate and in leukemic stem cell (LSC) persistence. It can be speculated that the observed deregulated activity of Aurora A and Plk1 enhances DNA damage, promoting the occurrence of additional genomic alterations contributing to TKI resistance and ultimately driving progression from chronic phase to blast crisis (BC). In this study, we propose a new therapeutic strategy based on the combination of Aurora kinase A or PLK1 inhibition with danusertib or volasertib, respectively, and WEE1 inhibition with AZD1775. Danusertib and volasertib used as single drugs induced apoptosis and G2/M-phase arrest, associated with accumulation of phospho-WEE1. Subsequent addition of the WEE1 inhibitor AZD1775 in combination significantly enhanced the induction of apoptotic cell death in TKI-sensitive and -resistant cell lines as compared to both danusertib and volasertib alone and to the simultaneous combination. This schedule indeed induced a significant increase of the DNA double-strand break marker γH2AX, forcing the cells through successive replication cycles ultimately resulting in apoptosis. Finally, combination of danusertib or volasertib+AZD1775 significantly reduced the clonogenic potential of CD34+ CML progenitors from BC patients. Our results may have implications for the development of innovative therapeutic approaches aimed to improve the outcomes of patients with multi-TKI-resistant or BC CML.

Droplet digital PCR for the detection of second-generation tyrosine kinase inhibitor-resistant BCR::ABL1 kinase domain mutations in chronic myeloid leukemia

One of the indications for BCR::ABL1 mutation testing in chronic myeloid leukemia (CML) is when tyrosine kinase inhibitor therapy (TKI) needs to be changed for unsatisfactory response. In this study, we evaluated a droplet digital PCR (ddPCR)-based multiplex strategy for the detection and quantitation of transcripts harbouring mutations conferring resistance to second-generation TKIs (2GTKIs). Parallel quantitation of e13a2, e14a2 and e1a2 BCR::ABL1 fusion transcripts enables to express results as percentage of mutation positive- over total BCR::ABL1 transcripts. We determined the limit of blank in 60 mutation-negative samples. Accuracy was demonstrated by further analysis of 48 samples already studied by next generation sequencing (NGS). Mutations could be called down to 0.5% and across 3-logs of BCR::ABL1 levels. Retrospective review of BCR::ABL1 NGS results in 513 consecutive CML patients with non-optimal response to first- or second-line TKI therapy suggested that a ddPCR-based approach targeted against 2GTKI-resistant mutations would score samples as mutation-negative in 22% of patients with warning response to imatinib but only in 6% of patients with warning response to 2GTKIs. We conclude ddPCR represents an attractive method for easy, accurate and rapid screening for 2GTKI-resistant mutations impacting on TKI selection, although ddPCR cannot identify compound mutations.

Thrombosis in multiple myeloma: risk stratification, antithrombotic prophylaxis, and management of acute events. A consensus-based position paper from an ad hoc expert panel

The introduction of new therapeutic agents in multiple myeloma (MM), including proteasome inhibitors, immunomodulatory drugs, and monoclonal antibodies, has improved the outcomes of patients but, in parallel, has changed the frequency and epidemiology of thrombotic events. Now, thrombosis is a significant cause of morbidity and mortality in MM patients, and optimal thromboprophylaxis is far from being reached. Moving from the recognition that the above issue represents an unmet clinical need, an Expert Panel assessed the scientific literature and composed a framework of recommendations for improving thrombosis control in patients candidates for active treatment for MM. The Panel generated clinical key questions using the criterion of clinical relevance through a Delphi process. It explored four domains, i.e., thrombotic risk factors and risk stratification, primary thromboprophylaxis, management of acute thrombotic events, and secondary thromboprophylaxis. The issued recommendations may assist hematologists in minimizing the risk of thrombosis and guarantee adherence to treatment in patients with MM candidates to active treatment.

Survival Risk Scores for Real-Life Relapsed/Refractory Multiple Myeloma Patients Receiving Elotuzumab or Carfilzomib In Combination With Lenalidomide and Dexamethasone as Salvage Therapy: Analysis of 919 Cases Outside Clinical Trials

The present study aimed to develop two survival risk scores (RS) for overall survival (OS, SRS^KRd/EloRd) and progression-free survival (PFS, PRS^KRd/EloRd) in 919 relapsed/refractory multiple myeloma (RRMM) patients who received carfilzomib, lenalidomide, and dexamethasone (KRd)/elotuzumab, lenalidomide, and dexamethasone (EloRd). The median OS was 35.4 months, with no significant difference between the KRd arm versus the EloRd arm. In the multivariate analysis, advanced ISS (HR = 1.31; P = 0.025), interval diagnosis–therapy (HR = 1.46; P = 0.001), number of previous lines of therapies (HR = 1.96; P < 0.0001), older age (HR = 1.72; P < 0.0001), and prior lenalidomide exposure (HR = 1.30; P = 0.026) remained independently associated with death. The median PFS was 20.3 months, with no difference between the two strategies. The multivariate model identified a significant progression/death risk increase for ISS III (HR = 1.37; P = 0.002), >3 previous lines of therapies (HR = 1.67; P < 0.0001), older age (HR = 1.64; P < 0.0001), and prior lenalidomide exposure (HR = 1.35; P = 0.003). Three risk SRS^KRd/EloRd categories were generated: low-risk (134 cases, 16.5%), intermediate-risk (467 cases, 57.3%), and high-risk categories (213 cases, 26.2%). The 1- and 2-year OS probability rates were 92.3% and 83.8% for the low-risk (HR = 1, reference category), 81.1% and 60.6% (HR = 2.73; P < 0.0001) for the intermediate-risk, and 65.5% and 42.5% (HR = 4.91; P < 0.0001) for the high-risk groups, respectively. Notably, unlike the low-risk group, which did not cross the median timeline, the OS median values were 36.6 and 18.6 months for the intermediate- and high-risk cases, respectively. Similarly, three PRS^KRd/EloRd risk categories were engendered. Based on such grouping, 338 (41.5%) cases were allocated in the low-, 248 (30.5%) in the intermediate-, and 228 (28.0%) in the high-risk groups. The 1- and 2-year PFS probability rates were 71.4% and 54.5% for the low-risk (HR = 1, reference category), 68.9% and 43.7% (HR = 1.95; P < 0.0001) for the intermediate-risk, and 48.0% and 27.1% (HR = 3.73; P < 0.0001) for the high-risk groups, respectively. The PFS median values were 29.0, 21.0, and 11.7 months for the low-, intermediate-, and high-risk cases. This analysis showed 2.7- and 4.9-fold increased risk of death for the intermediate- and high-risk cases treated with KRd/EloRd as salvage therapy. The combined progression/death risks of the two categories were increased 1.3- and 2.2-fold compared to the low-risk group. In conclusion, SRS^KRd/EloRd and PRS^KRd/EloRd may represent accessible and globally applicable models in daily clinical practice and ultimately represent a prognostic tool for RRMM patients who received KRd or EloRd.

BoBafit: a copy number clustering tool designed to refit and recalibrate the baseline region of tumors’ profiles

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Tools generating CN profiles derive the baseline region from samples’ median CN signal.

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This canonical approach might cause wrongly estimated CN profile in complex karyotypes.

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CNAs call is crucial for patients’ risk stratification aimed at personalized treatment.

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BoBafit computes the correct baseline region and the CN profile, taking into account tumor genomic complexity and samples-specific alterations.

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BoBafit should be implemented within CN analysis pipelines especially for clinical aims.

Human cancer arises from a population of cells that have acquired a wide range of genetic alterations, most of which are targets of therapeutic treatments or are used as prognostic factors for patient’s risk stratification. Among these, copy number alterations (CNAs) are quite frequent. Currently, several molecular biology technologies, such as microarrays, NGS and single-cell approaches are used to define the genomic profile of tumor samples. Output data need to be analyzed with bioinformatic approaches and particularly by employing computational algorithms.

Molecular biology tools estimate the baseline region by comparing either the mean probe signals, or the number of reads to the reference genome. However, when tumors display complex karyotypes, this type of approach could fail the baseline region estimation and consequently cause errors in the CNAs call. To overcome this issue, we designed an R-package, BoBafit, able to check and, eventually, to adjust the baseline region, according to both the tumor-specific alterations’ context and the sample-specific clustered genomic lesions.

Several databases have been chosen to set up and validate the designed package, thus demonstrating the potential of BoBafit to adjust copy number (CN) data from different tumors and analysis techniques.

Relevantly, the analysis highlighted that up to 25% of samples need a baseline region adjustment and a redefinition of CNAs calls, thus causing a change in the prognostic risk classification of the patients.

We support the implementation of BoBafit within CN analysis bioinformatics pipelines to ensure a correct patient’s stratification in risk categories, regardless of the tumor type.

Monoclonal gammopathy of renal significance (MGRS): Real-world data on outcomes and prognostic factors

Monoclonal gammopathy of renal significance (MGRS) is a recognized clinical entity. Literature regarding treatment and its outcomes in MGRS is sparse due to the rarity and misdiagnosis of MGRS. We retrospectively analyzed 280 adults with an MGRS diagnosis from 2003 to 2020 across 19 clinical centers from 12 countries. All cases required renal biopsy for the pathological diagnosis of MGRS. Amyloidosis‐related to MGRS (MGRS‐A) was present in 180 patients; nonamyloidosis MGRS (MGRS‐NA), including a broad spectrum of renal pathologies, was diagnosed in 100 patients. The median overall survival in the studied cohort was 121.0 months (95% CI: 105.0–121.0). Patients with MGRS‐A had a shorter overall survival than patients with MGRS‐NA (HR = 0.41, 95%CI: 0.25–0.69; p = 0.0007). Both hematologic and renal responses were associated with longer survival. Achievement of ≥VGPR was generally predictive of a renal response (OR = 8.03 95%CI: 4.04–115.96; p < 0.0001), one‐fourth of patients with ≥VGPR were renal nonresponders. In MGRS‐A, factors associated with poor prognosis included elevated levels of creatinine, beta‐2‐microglobulin, and hemodialysis at diagnosis. In MGRS‐NA, only age >65 years was associated with increased risk of death. Treatments provided similar hematologic response rates in both types of MGRS. Autologous stem cell transplantation led to better response than other treatments. This multicenter and international effort is currently the largest report on MGRS.

Early Light Chains Removal and Albumin Levels with a Double Filter-Based Extracorporeal Treatment for Acute Myeloma Kidney

Renal impairment in Multiple Myeloma (MM) represents one of the most important factors that influences patient survival. In fact, before the introduction of modern chemotherapy, less than 25% of patients with acute kidney injury (AKI) and MM who required dialysis recovered sufficient renal function to become independent from dialysis, with a median overall survival of less than 1 year. There are many other factors involved in determining patient survival. In this study we aimed to investigate the role of double filter-based extracorporeal treatment for removal of serum free light chains (sFLC) in acute myeloma kidney (AKI for MM) and to evaluate patient overall survival. All patients received Bortezomib-based chemotherapy and extracorporeal treatment for sFLC removal. For each session 2 dialyzers of the same kind were used. The dialytic dose was not related to the degree of renal function but to the removal of sFLC. The factors that have been found to be significantly associated with lower mortality were reduction of sFLC at day 12 and day 30, >50% reduction of sFLC at day 30, number of sessions and independence from dialysis. Among baseline characteristics, albumin level was statistically associated with the patients’ outcome. Our analysis highlights the importance of the early treatment for removal of sFLC in AKI for MM. These results indicate that the early removal of sFLC can improve patient’s outcome.

CAMMA 3: A multicenter phase Ib trial evaluating the safety, pharmacokinetics, and activity of subcutaneous cevostamab monotherapy in patients with relapsed or refractory multiple myeloma

TPS8070

Background: Multiple myeloma (MM) remains an incurable disease. Although new treatment paradigms have increased survival, most patients relapse and treatment in later lines remains a challenge. Prognosis for patients refractory to immunomodulatory drugs, proteasome inhibitors and anti-CD38 antibodies is extremely poor, with an estimated survival of < 1 year (Gandhi et al. 2019). Therefore, patients with relapsed/refractory (R/R) disease represent a high unmet need, and new targets and treatment modalities are needed. Cevostamab is an IgG1-based T-cell-dependent bispecific antibody engineered to target the most membrane-proximal domain of fragment crystallizable receptor-like 5 (FcRH5) on myeloma cells, and cluster of differentiation 3 (CD3) on T cells. This dual binding results in efficient immunological synapse formation and T-cell-mediated killing of myeloma cells. In the ongoing first-in-human Phase I GO39775 study, intravenous (IV) administration of cevostamab monotherapy continues to show clinically meaningful activity and durable responses in patients with heavily pre-treated R/R MM (Trudel et al. ASH 2021), and uses Cycle (C) 1 step-up dosing for the mitigation of cytokine release syndrome (CRS). Subcutaneous (SC) delivery of antibody therapies has been shown to be effective and well tolerated and offers several advantages over IV administration in regards to improved healthcare utilization, including ease of administration, reduced treatment burden and reduced hospitalization. The slower absorption rate observed with SC versus IV antibody therapies may also support the potential for SC cevostamab to provide a further improved CRS profile (Bartlett et al. ASH 2021). CAMMA 3 (GO43227; ISRCTN26168155) is an open-label, multicenter, Phase Ib dose-escalation and dose-expansion trial evaluating the safety, tolerability, pharmacokinetics (PK) and preliminary activity of SC cevostamab monotherapy in patients with R/R MM. Methods: For inclusion, patients must be aged ≥18 years and must have R/R MM for which no established therapies are available or appropriate. Cevostamab is administered by SC injection in 28-day cycles, with step-up dosing in C1, q2w dosing in C2–6, and q4w dosing in C7–13. Patients may receive up to 13 cycles unless there is disease progression or unacceptable toxicity. Patients who respond to cevostamab but develop recurrent or progressive disease after 13 cycles may be eligible for cevostamab re-treatment. Primary objectives are to evaluate the safety and tolerability (including the maximum tolerated dose and dose-limiting toxicities) of SC cevostamab and to identify a recommended Phase II dose. Secondary objectives include assessment of PK, activity, and immunogenicity, and identification of biomarkers associated with response and resistance. Clinical trial information: 26168155.

Impact of infectious comorbidity and overall time of hospitalization in total outpatient management of acute myeloid leukemia patients following venetoclax and hypomethylating agents

Venetoclax (VEN) and hypomethylating agent (HMAs) regimens are emerging as the standard of care for unfit for chemotherapy acute myeloid leukemia (AML) patients, but the safety and feasibility of a total outpatient management have not been fully investigated. Fifty‐nine AML patients with active disease received VEN and HMAs. Nineteen out of 59 (32.2%) patients received the first cycle as inpatients, whereas 40/59 (67.8%) patients were treated in the outpatient setting. No significant differences were observed with regard to incidence of adverse events (AEs), including tumor lysis syndrome (TLS), and the 30‐day and 60‐day mortality was comparable. Notably, an infectious prophylaxis inspired to that adopted during intensive chemotherapy resulted in a low infection rate with a reduced bacterial infections incidence in out‐ versus hospitalized patients (p < .0001). The overall time of hospitalization was significantly shorter in patients who received a total outpatient treatment as compared to those who received the first cycle as inpatients (5.9 vs. 39.7 days, p < .0001). Despite the adopted differences in treatment management, the efficacy was similar. These data indicate that a total outpatient management of VEN and HMAs is feasible in AML patients without negatively impacting on treatment efficacy and may yield pharmacoeconomic and quality‐of‐life benefits.

Efficacy and safety of teclistamab (tec), a B-cell maturation antigen (BCMA) x CD3 bispecific antibody, in patients (pts) with relapsed/refractory multiple myeloma (RRMM) after exposure to other BCMA-targeted agents

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Background: Tec (JNJ-64007957) is a BCMA x CD3 bispecific antibody (Ab) that redirects CD3+ T cells to mediate T-cell activation and subsequent lysis of BCMA-expressing myeloma cells. MajesTEC-1 is a multicohort, open-label phase 1/2 study of tec in pts with RRMM who previously received ≥3 prior lines of therapy (LOT). Results from a pooled analysis of phase 1 and phase 2 cohort A (median follow-up 7.8 mo) demonstrated an overall response rate (ORR) of 62.0% in pts with no prior anti-BCMA treatment (tx). We present initial results from cohort C, in which pts had prior exposure to an anti-BCMA tx. Methods: Eligible pts (age ≥18 y) had documented MM per IMWG criteria and had received ≥3 prior LOT including a PI, an IMiD, an anti-CD38 Ab, and an anti-BCMA tx (chimeric antigen receptor T [CAR-T] or Ab drug conjugate [ADC]). Pts were enrolled into a Simon’s stage design, receiving weekly subcutaneous tec 1.5 mg/kg preceded by step-up doses of 0.06 and 0.3 mg/kg. Primary endpoint was ORR (per IMWG 2016 criteria). AEs were graded per CTCAE v4.03; cytokine release syndrome (CRS) and immune effector cell–associated neurotoxicity syndrome (ICANS) were graded per ASTCT guidelines. Results: As of Sep 7, 2021, 38 pts in cohort C received tec (63% male; median age 63.5 y [range 32–82]; median prior LOT 6 [range 3–14]). 32 (84%) pts were refractory to last LOT; 25 (66%) were refractory to an anti-BCMA tx. Of 25 pts evaluated for efficacy, 16 (64%) had prior ADC, 11 (44%) prior CAR-T (2 pts received both). With median follow-up of 6.9 mo (range 0.7–8.7), ORR was 40% (95% CI 21–61). 5 pts (20%) achieved a complete response or better. The ORR (95% CI) was 38% (15–65) in ADC-exposed pts and 45% (17–77) in CAR-T–exposed pts. Most responses occurred rapidly; 7/25 pts had responses that deepened over time. Median time (range) to first and best response was 1.2 mo (0.2–4.9) and 2.1 mo (1.1–5.7), respectively. Median duration of response was not reached. The safety profile was comparable with that observed in BMCA tx-naive pts, with no new safety concerns. 16 pts (42%; grade 3/4 26%) had infections. Most common AEs (n = 38) were CRS (63%; all grade 1/2; median [range] time to CRS onset: 3 d [2–6], duration of CRS: 2 d [1–4]), neutropenia (55%; grade 3/4 50%), thrombocytopenia (42%; grade 3/4 29%), anemia (39%; grade 3/4 29%), and lymphopenia (40%; grade 3/4 37%). One pt had grade 3 ICANS that resolved with supportive care; pt remains on tx. No pts developed anti-tec Abs. Baseline BCMA expression was comparable with that observed in BCMA tx-naive pts. Updated efficacy and safety data will be presented for 40 pts. Conclusions: Initial results of serial targeting of BCMA with tec following ADC or CAR-T tx suggest a promising ORR with responses occurring early and deepening over time. A well-tolerated safety profile was observed in pts previously treated with anti-BCMA tx. Clinical trial information: NCT04557098.

Baseline CD22 fluorescent intensity correlates with patient outcome after Inotuzumab Ozogamicin treatment

Antigen-directed target therapy for B-cell acute lymphoblastic leukemia (B-ALL) is now the standard of care for relapsed/refractory (R/R) disease. A comprehensive determination of the target itself is mandatory to aid physician's choice. We determined baseline CD22 expression percentage and fluorescent intensity (FI) on lymphoblasts of 30 patients with R/R B-ALL treated with anti-CD22 immunoconjugate drug Inotuzumab Ozogamicin (INO) and analyzed the impact of both parameters on patient outcome.Most patients (24/30, 80%) had a high leukemic blast CD22-positivity defined as ≥90%. We did not observe a benefit in terms of CR, OS and DoR for patients with CD22 ≥90% vs CD22<90%.Concerning CD22-FI quartile analysis we appreciated a trend for superior response rates in higher quartiles (Q₂ -Q₄ ) compared to Q₁ and a significant benefit in terms of OS and DoR for patients with higher CD22-FI.INO demonstrates to be effective also in patients with lower CD22 expression, but therapeutical benefits are more evident in patients with higher CD22-FI. The evaluation of both CD22 percentage and CD22-FI of the leukemic blast may help physicians in therapeutic choices for R/R B-ALL patients when multiple treatment options are available, although no CD22 expression threshold can currently be identified below which INO should be considered not effective. This article is protected by copyright. All rights reserved.

Elotuzumab plus Lenalidomide and Dexamethasone in Relapsed/Refractory Multiple Myeloma: Extended 3-year follow-up of a multicenter, retrospective clinical experience with 319 cases outside of controlled clinical trials

The combination of elotuzumab, lenalidomide, and dexamethasone (EloRd) enhanced the clinical benefit over Rd with a manageable toxicity profile in the ELOQUENT-2 trial, leading to its approval in relapsed/refractory multiple myeloma (RRMM). The present study is a 3-year follow-up update of a previously published Italian real-life RRMM cohort of patients treated with EloRd. This revised analysis entered 319 RRMM patients accrued in 41 Italian centers. After a median follow-up of 36 months (range 6-55), 236 patients experienced disease progression or died. Median progression-free survival (PFS) and overall survival (OS) were 18.4 and 34 months, respectively. The updated multivariate analyses showed a significant reduction of PFS and OS benefit magnitude only in cases with ISS stage III. Major adverse events included grade 3/4 neutropenia (18.5%), anemia (15.4%), lymphocytopenia (12.5%), and thrombocytopenia (10.7%), while infection rates and pneumonia were 33.9% and 18.9%, respectively. No new safety signals with longer follow-up have been observed. Of 319 patients, 245 (76.7%) reached at least a partial remission. A significantly lower response rate was found in patients previously exposed to lenalidomide. In conclusion, our study confirms that EloRd is a safe and effective regimen for RRMM patients, maintaining benefits across multiple unfavorable subgroups. This article is protected by copyright. All rights reserved.

Second Revision of the International Staging System (R2-ISS) for Overall Survival in Multiple Myeloma: A European Myeloma Network (EMN) Report Within the HARMONY Project

PURPOSE

Patients with newly diagnosed multiple myeloma (NDMM) show heterogeneous outcomes, and approximately 60% of them are at intermediate-risk according to the Revised International Staging system (R-ISS), the standard-of-care risk stratification model. Moreover, chromosome 1q gain/amplification (1q+) recently proved to be a poor prognostic factor. In this study, we revised the R-ISS by analyzing the additive value of each single risk feature, including 1q+.

PATIENTS AND METHODS

The European Myeloma Network, within the HARMONY project, collected individual data from 10,843 patients with NDMM enrolled in 16 clinical trials. An additive scoring system on the basis of top features predicting progression-free survival (PFS) and overall survival (OS) was developed and validated.

RESULTS

In the training set (N = 7,072), at a median follow-up of 75 months, ISS, del(17p), lactate dehydrogenase, t(4;14), and 1q+ had the highest impact on PFS and OS. These variables were all simultaneously present in 2,226 patients. A value was assigned to each risk feature according to their OS impact (ISS-III 1.5, ISS-II 1, del(17p) 1, high lactate dehydrogenase 1, and 1q+ 0.5 points). Patients were stratified into four risk groups according to the total additive score: low (Second Revision of the International Staging System [R2-ISS]-I, 19.2%, 0 points), low-intermediate (II, 30.8%, 0.5-1 points), intermediate-high (III, 41.2%, 1.5-2.5 points), high (IV, 8.8%, 3-5 points). Median OS was not reached versus 109.2 versus 68.5 versus 37.9 months, and median PFS was 68 versus 45.5 versus 30.2 versus 19.9 months, respectively. The score was validated in an independent validation set (N = 3,771, of whom 1,214 were with complete data to calculate R2-ISS) maintaining its prognostic value.

CONCLUSION

The R2-ISS is a simple prognostic staging system allowing a better stratification of patients with intermediate-risk NDMM. The additive nature of this score fosters its future implementation with new prognostic variables.

Treatment Regimens for Transplant-Ineligible Patients With Newly Diagnosed Multiple Myeloma: A Systematic Literature Review and Network Meta-analysis

Introduction

Many treatment regimens have been evaluated in transplant-ineligible (TIE) patients with newly diagnosed multiple myeloma (NDMM). The objective of this study was to compare the efficacy of relevant therapies for the treatment of TIE patients with NDMM.

Methods

Progression-free survival (PFS) and overall survival (OS) from large randomised controlled trials (RCTs) evaluating different treatment options for TIE patients with NDMM were compared in a network meta-analysis (NMA). The NMA includes recent primary and long-term OS readouts from SWOG S0777, ENDURANCE, MAIA, and ALCYONE. Relevant trials were identified through a systematic literature review. Relative efficacy measures (i.e., hazard ratios [HRs] for PFS and OS) were extracted and synthesised in random-effects NMAs.

Results

A total of 122 publications describing 45 unique RCTs was identified. Continuous lenalidomide/dexamethasone (Rd) was selected as the referent comparator. Daratumumab-containing treatments (daratumumab/lenalidomide/dexamethasone [D-Rd], daratumumab/bortezomib/melphalan/prednisone [D-VMP]) and bortezomib/lenalidomide/dexamethasone (VRd) had the highest probabilities of being more effective than Rd continuous for PFS (HR: D-Rd, 0.53; D-VMP, 0.57, VRd, 0.77) and OS (HR: D-Rd, 0.68; VRd, 0.77, D-VMP, 0.78). D-Rd had the highest chance of being ranked as the most effective treatment with respect to PFS and OS. Results using a smaller network focusing on only those regimens that are relevant in Europe were consistent with the primary analysis.

Conclusions

These comparative effectiveness data may help inform treatment selection in TIE patients with NDMM.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02083-8.