Efficacy and safety of tixagevimab/cilgavimab as passive immunisation against COVID-19 infections in patients with hematological malignancies.

Monoclonal antibodies, as tixagevimab/cilgavimab, have been introduced as prophylaxis against COVID-19 infections in high-risk populations. However, data on efficacy are limited. This study investigates efficacy and tolerability of tixagevimab/cilgavimab in hematological patients under real-life conditions. Tixagevimab/cilgavimab was administered to 155 hematological patients (March-August 2022) at two Austrian centres. S/RBD-antibody assessments were performed before (T0), four weeks (T1), and six months (T2) after application. Side effects, the occurrence of COVID-19 infections, and the course of S/RBD-antibody titres were analysed retrospectively in relation to clinical variables. 155 hematological patients, who refused tixagevimab/cilgavimab, were included as a control group to compare the frequency of COVID-19 infections. Of all immunised patients (52.3% males; 91% triple vaccinated), 25.8% had a COVID-19 breakthrough infection (76% mild) compared to 43.9% in the control group. Patients with chronic lymphocytic leukaemia (CLL)/lymphoma were at highest risk of a COVID-19 infection (OR = 2.21; 95% CI 1.05-4.65; p = 0.037). After immunisation, a steep increase in median antibody levels (1193.4BAU/ml, IQR 0-2318.94) was observed in 67.8%, followed by a rapid decrease between T1 and T2 (465.95BAU/ml, IQR 0-1900.65.3) with the greatest declines in CLL/lymphoma (848.7BAU/ml, IQR 0-1949.6, p = 0.026). Side-effects occurred in 21.2% (CTCAE I/II). These real-world data indicate that S/RBD antibodies respond rapidly after passive immunisation in all hematological patients without safety concerns. Given the rapid decline in S/RBD antibodies, early booster immunisations should be considered for future scenarios in this vulnerable group.

Amp(1q) and tetraploidy are commonly acquired chromosomal abnormalities in relapsed multiple myeloma.

Long-term disease control in multiple myeloma (MM) is typically an unmet medical need, and most patients experience multiple relapses. Fluorescence in situ hybridization (FISH) is the standard technique to detect chromosomal abnormalities (CAs), which are important to estimate the prognosis of MM and the allocation of risk adapted therapies. In advanced stages, the importance of CAs needs further investigation. From 148 MM patients, two or more paired samples, at least one of which was collected at relapse, were analyzed by FISH. Using targeted next-generation sequencing, we molecularly investigated samples harboring relapse-associated CAs. Sixty-one percent of the patients showed a change in the cytogenetic profile during the disease course, including 10% who acquired high-risk cytogenetics. Amp(1q) (≥4 copies of 1q21), driven by an additional increase in copy number in patients who already had 3 copies of 1q21, was the most common acquired CA with 16% affected patients. Tetraploidy, found in 10% of the samples collected at the last time-point, was unstable over the course of the disease and was associated with TP53 lesions. Our results indicate that cytogenetic progression is common in relapsed patients. The relatively high frequency of amp(1q) suggests an active role for this CA in disease progression.

Clonal dynamics in a composite chronic lymphocytic leukemia and hairy cell leukemia-variant.

Composite lymphoma is the rare simultaneous manifestation of two distinct lymphomas. Chronic lymphocytic leukemia (CLL) has a propensity for occurring in composite lymphomas, a phenomenon that remains to be elucidated. We applied cytogenetics, droplet digital polymerase chain reaction, and massively parallel sequencing to analyze longitudinally a patient with CLL, who 3 years later showed transformation to a hairy cell leukemia-variant (HCL-V). Outgrowth of the IGHV4-34-positive HCL-V clone at the expense of the initially dominant CLL clone with trisomy 12 and MED12 mutation started before CLL-guided treatment and was accompanied by a TP53 mutation, which was already detectable at diagnosis of CLL. Furthermore, deep sequencing of IGH showed a composite lymphoma with presence of both disease components at all analyzed timepoints (down to a minor clone: major clone ratio of ~1:1000). Overall, our analyses showed a disease course that resembled clonal dynamics reported for malignancies with intratumoral heterogeneity and illustrate the utility of deep sequencing of IGH to detect distinct clonal populations at diagnosis, monitor clonal response to therapy, and possibly improve clinical outcomes.

Early autologous and allogeneic peripheral blood stem cell transplantation for adult patients with acute B and T cell precursor neoplasms: a 12-year single center experience.

Adult acute lymphoblastic leukemia/lymphoma (ALL/LBL) is a rare and heterogeneous malignancy characterized by uncontrolled proliferation of B or T cell precursor cells. Here, we retrospectively analyzed the outcome of early autologous stem cell transplantation in standard-risk patients in first complete remission (n=24) and of allogeneic transplantation in high and highest risk, and relapsed/refractory patients (n=35). The 10-year overall survival after autologous transplantation was 45%. The 10-year overall survival after allogeneic transplantation was 58%. The cumulative incidence of relapse was 29% after allogeneic and 67% after autologous transplantation. The cumulative incidence of non-relapse mortality was 0% after autologous and 12% after allogeneic transplantation. This retrospective single center analysis in a limited number of standard-risk patients clearly demonstrates that early autologous transplantation in first complete remission leads to an acceptable long-term outcome with a short overall treatment duration of less than 6 months compared with more than 2 years with conventional chemotherapy. More sensitive and standardized methods to detect minimal residual disease (MRD) will further help to identify those patients more accurately who are most likely to benefit from such a short and intensive treatment strategy (i.e., MRD negative standard-risk patients) or those who require early targeted therapy (e.g., blinatumomab) in case of MRD positivity. Early allogeneic transplantation results in long-term survival/cure in nearly two-thirds of all high and highest risk, and relapsed/refractory patients.

The prognostic value of additional copies of 1q21 in multiple myeloma depends on the primary genetic event.

Hyperdiploidy (HRD) and specific immunoglobulin heavy locus (IGH) translocations are primary chromosomal abnormalities (CA) in multiple myeloma (MM). In this retrospective study of 794 MM patients we aimed to investigate clinical features and common CA including gain(1q) in separate subgroups defined by primary CA. In the entire group, we confirmed that gain(1q) was associated with short time to next treatment and adverse overall survival (OS). The impact was worse for four or more copies of 1q21 as compared to three copies. However, in a subgroup of patients with clonal gain(11q) and without known primary IGH translocations (CG11q), already three copies of 1q21 were associated with a poor outcome; in the absence of gain(1q), patients in this subgroup had a remarkably long median OS of more than nine years. These cases were associated with HRD, coexpression of CD56 and CD117, male gender, and IgG subtype. In non-CG11q patients, four or more copies of 1q21 (but not three copies) had a significant adverse impact on outcome. Several associations with CA and clinical findings were observed for the defined subgroups. As an example, we found a predominance of early tetraploidy, plasma cell leukemia, and female gender in the t(14;16) subgroup. Our results underscore the importance of subgrouping in MM.

Bendamustine plus Rituximab Versus R-CHOP as First-Line Treatment for Patients with Follicular Lymphoma Grade 3A: Evidence from a Multicenter, Retrospective Study.

BACKGROUND: Rituximab plus bendamustine (R-B) has been demonstrated to improve outcomes and reduce toxicity compared with rituximab, cyclophosphamide, doxorubicin, and prednisone (R-CHOP) in follicular lymphoma (FL). Nevertheless, in clinical practice, many centers still prefer R-CHOP to R-B in patients with FL grade 3A (FL3A). Therefore, we retrospectively assessed patients with FL3A treated with either R-CHOP or R-B in five European cancer centers and compared their outcomes. MATERIALS AND METHODS: We retrospectively assessed 132 patients affected by FL grade 3A treated with either R-B or R-CHOP in the first line and evaluated outcome and toxicity according to the type of treatment. This study included 101 patients who were a subgroup of a previously published cohort. RESULTS: R-B was less toxic and achieved a similar percentage of complete remissions compared with R-CHOP (97% vs. 96%, p = .3). During follow-up, 10 (16%) patients relapsed after R-B and 29 (41%) after R-CHOP (p = .001), leading to a median progression-free survival (PFS) of 15 versus 11.7 years, respectively (p = .03). Furthermore, R-B overcame the negative prognostic impact of BCL2 expression (15 vs. 4.8 years; p = .001). However, median overall survival was similar between both groups (not reached for both; p = .8). CONCLUSION: R-B as a first-line treatment of FL3A is better tolerated than R-CHOP and seems to induce more profound responses, leading to a significantly lower relapse rate and prolonged PFS. Therefore, R-B is a valid treatment option for FL grade 3A. IMPLICATIONS FOR PRACTICE: Rituximab plus bendamustine (R-B) has shown to be less toxic and more effective than rituximab, cyclophosphamide, doxorubicin, and prednisone (R-CHOP) in follicular lymphoma grade 3A. Although both regimens can induce a complete remission in >95% of patients, relapses occur more frequently after R-CHOP than R-B, leading to a significantly longer progression-free survival in the latter. R-B is also able to overcome the impact of negative prognosticators, such as BCL2 expression. However, because of the indolent course of this disease and efficient salvage treatments, overall survival was similar in both treatment groups. Therefore, R-B is a valid treatment option in this patient setting.

Towards Molecular Profiling in Multiple Myeloma: A Literature Review and Early Indications of Its Efficacy for Informing Treatment Strategies.

Multiple myeloma (MM), the second most common hematologic malignancy, is characterized by the clonal expansion of plasma cells. Despite dramatic improvements in patients' survival over the past decade due to advances in therapy exploiting novel molecular targets (immunomodulatory drugs, proteasome inhibitors and monoclonal antibodies), the treatment of relapsed and refractory disease remains challenging. Recent studies confirmed complex, dynamic, and heterogeneous genomic alterations without unifying gene mutations in MM patients. In the current review, we survey recent therapeutic strategies, as well as molecular profiling data on MM, with emphasis on relapsed and refractory cases. A critical appraisal of novel findings and of their potential therapeutic implications will be discussed in detail, along with the author's own experiences/views.

Predominant expression of truncated EpCAM is associated with a more aggressive phenotype and predicts poor overall survival in colorectal cancer.

Regulated intramembrane proteolysis (RIP) has been shown to be an important mechanism for oncogenic activation of EpCAM through nuclear translocation of the intracellular domain EpICD. Recently, we identified two different membranous EpCAM variants namely EpCAM(MF) (full-length) and EpCAM(MT) (truncated) to be expressed in the majority of human epithelial tumors. The aim of our study was to evaluate the potential role of these two protein variants as additional prognostic biomarkers in colorectal cancer. In most studies only one antibody targeting the extracellular domain of EpCAM (EpEX) has been used, whereas in the present study additionally an antibody which detects the intracellular domain (EpICD) was applied to discriminate between different EpCAM variants. Using immunohistochemistry, we analyzed the expression of EpCAM(MF) and EpCAM(MT) variants in 640 patients with colorectal cancer and determined their correlations with other prognostic factors and clinical outcome. A statistically significant association was observed for EpCAM(MT) with advanced tumor stage (p < 0.001), histological grade (p = 0.01), vascular (p < 0.001) and marginal (p = 0.002) invasion. Survival analysis demonstrated reduced overall survival (p < 0.004) in patients with tumors expressing the EpCAM(MT) phenotype when compared to patients with tumors expressing the EpCAM(MF) variant. In conclusion, this study for the first time indicates that expression of EpCAM(MT) is associated with a more aggressive phenotype and predicts poor survival in patients with colorectal cancer.

Lenalidomide in Relapsed or Refractory Diffuse Large B-Cell Lymphoma: Is It a Valid Treatment Option?

BACKGROUND: Despite the advent of new treatment strategies, many patients with diffuse large B-cell lymphoma (DLBCL) relapse or die of the disease. Prospective clinical trials have demonstrated that lenalidomide is an effective and safe treatment option, especially for non-germinal center B-cell (non-GCB) DLBCL. However, routine clinical data are lacking, which is why we provide the results of the so-far largest relapsed/refractory (R/R) DLBCL real-life analysis. METHODS: We retrospectively assessed 123 R/R DLBCL patients who received either 15 or 25 mg/day of lenalidomide from January 2006 to January 2015. RESULTS: During a median follow-up period of 4.5 years, complete remission was achieved in 32% and a partial remission in 33% non-GCB patients compared with 0% and 3% in the GCB group (p < .001 and .001, respectively), with median response durations of 15 and 5 months, respectively (p < .001). Lenalidomide at 25 mg was superior to 15 mg in terms of response (complete remission 21% and partial remission 23% vs. 0% and 8%; p = .007 and .05) and median response duration (10 vs. 4 months; p = .03). Toxicity was limited and reversible. Median progression-free survival differed between non-GCB and GCB patients (37 vs. 30 months; p < .001) and between the two dosages (24 vs. 34 months; p = .002). However, overall survival was similar between the subgroups (38-42 months). CONCLUSION: We provide evidence that lenalidomide is a valid treatment option for R/R DLBCL, with limited and reversible toxicity, and is more efficient in non-GCB DLBCL and at higher doses. IMPLICATIONS FOR PRACTICE: Despite the advent of new treatment strategies, many patients with diffuse large B-cell lymphoma (DLBCL) relapse or die of the disease; hence, novel therapeutic approaches are urgently needed. This study confirms that lenalidomide is a valid and well-tolerated treatment option for relapsed/refractory (R/R) DLBCL. Superior outcomes were observed in non-germinal center B-cell (GCB) DLBCL, probably because of inhibition of the nuclear factor-κB pathway. Similarly, high drug doses resulted in greater clinical benefits. Overall, lenalidomide is a suitable therapeutic option for R/R DLBCL, especially in non-GCB DLBCL, and 25 mg/day dosing should be preferred.

Bendamustine plus rituximab versus R-CHOP as first-line treatment for patients with indolent non-Hodgkin's lymphoma: evidence from a multicenter, retrospective study.

The optimal first-line treatment for advanced low-grade non-Hodgkin lymphomas (LG-NHL) is still highly debated. Recently, the StiL and the BRIGHT trials showed that the combination of rituximab and bendamustine (R-B) is non-inferior to rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) with a better toxicity profile. Utilizing a retrospective analysis, we compared the efficacy and safety of both regimens in clinical practice. From November 1995 to January 2014, 263 LG-NHL patients treated with either R-B or R-CHOP were retrospectively assessed in seven European cancer centers. Ninety patients were treated with R-B and 173 with R-CHOP. Overall response rate was 94 and 92 % for the R-B and the R-CHOP group, respectively. The percentage of complete response was similar for both groups (63 vs. 66 % with R-B and R-CHOP, respectively; p = 0.8). R-B was better tolerated and less toxic than R-CHOP. The median follow-up was 6.8 and 5.9 years for the R-CHOP and the R-B group, respectively. Overall, no difference in progression-free survival (PFS) (108 vs. 110 months; p = 0.1) was observed in the R-B group compared to the R-CHOP cohort. Nevertheless, R-B significantly prolonged PFS in FL patients (152 and 132 months in the R-B and R-CHOP group, respectively; p = 0.05). However, this result was not verified in multivariate analysis probably due to the limits of the present study. We confirm that the R-B regimen administered in patients with LG-NHL is an effective and less toxic therapeutic option than R-CHOP in clinical practice.

The Aplidin analogs PM01215 and PM02781 inhibit angiogenesis in vitro and in vivo.

BACKGROUND: Novel synthesized analogs of Aplidin, PM01215 and PM02781, were tested for antiangiogenic effects on primary human endothelial cells in vitro and for inhibition of angiogenesis and tumor growth in vivo. METHODS: Antiangiogenic activity of both derivatives was evaluated by real-time cell proliferation, capillary tube formation and vascular endothelial growth factor (VEGF)-induced spheroid sprouting assays. Distribution of endothelial cells in the different phases of the cell cycle was analyzed by flow cytometry. Aplidin analogs were tested in vivo in chicken chorioallantoic membrane (CAM) assays. RESULTS: Both derivatives inhibited angiogenic capacities of human endothelial cells (HUVECs) in vitro at low nanomolar concentrations. Antiangiogenic effects of both analogs were observed in the CAM. In addition, growth of human multiple myeloma xenografts in vivo in CAM was significantly reduced after application of both analogs. On the molecular level, both derivatives induced cell cycle arrest in G1 phase. This growth arrest of endothelial cells correlated with induction of the cell cycle inhibitor p16(INK4A) and increased senescence-associated beta galactosidase activity. In addition, Aplidin analogs induced oxidative stress and decreased production of the vascular maturation factors Vasohibin-1 and Dickkopf-3. CONCLUSIONS: From these findings we conclude that both analogs are promising agents for the development of antiangiogenic drugs acting independent on classical inhibition of VEGF signaling.

Anti-T-lymphocyte globulin (ATLG) compared to post-transplant cyclophosphamide as GvHD prophylaxis in ALL patients undergoing allogeneic stem cell transplantation.

We retrospectively analyzed high-risk ALL patients in CR1 receiving total body irradiation based conditioning regimen with ATLG (n = 74) or PTCy (n = 73) for GVHD prophylaxis. The 3-year OS and LFS were similar in both groups: 65 and 60% in the ATLG group and 64 and 67% in the PTCy group (p = 0.9 and 0.5, respectively). CIR and NRM rate at three years was 12 and 21% after PTCy and 19 and 20% after ATLG (p = 0.4 and p = 0.9, respectively). Acute GvHD grades II-IV and grades III/IV at 100 days was 46 and 19% after PTCy and 33 and 10% after ATLG (p = 0.08 and p = 0.9, respectively). Chronic GvHD of all grade at two years was higher after PTCy: 55% versus 26% (p < 0.001). Based on the propensity score matching (PSM) analysis, aGvHD grades II-IV was trending higher in the PTCy group compared to the ATLG group (p = 0.07). In contrast to the PSM analysis, on multivariate analysis the receipt of PTCy compared with ATLG was associated with a reduced CIR (p = 0.026). Our retrospective single-center analysis shows a lower incidence of acute and chronic GvHD while displaying similar LFS and OS after ATLG compared to PTCy in TBI based allogeneic stem cell transplantation for high-risk ALL.

Poor Mobilizers in Lymphoma but Not Myeloma Patients Had Significantly Poorer Progression-Free Survival after Autologous Stem Cell Transplantation: Results of a Large Retrospective, Single-Center Observational Study.

In our single-center study, 357 myeloma and lymphoma patients between 2009 and 2019 were mobilized with granulocyte colony-stimulating factor (G-CSF 7.5 µg/kg bid for four days) plus a fixed dose of 24 mg Plerixafor when indicated (Plerixafor Group, n = 187) or G-CSF alone (G-CSF Group, n = 170). The target CD34 cell yields were ≥2.0 × 106 CD34+ cells/kg in lymphoma and ≥4.0 × 106 CD34+ cells/kg in myeloma patients to enable putative second transplants in the latter. There were no significant differences in engraftment kinetics or transfusion requirements between the Plerixafor Group and the control group in the myeloma cohort, with lymphoma patients not requiring Plerixafor showing significantly faster neutrophil recovery, a trend to faster platelet recovery, and a significantly lower need for platelet transfusions, probably due to the significantly lower number of CD34-positive cells re-transfused. While in myeloma patients the outcome (overall survival, progression-free survival) following autologous stem cell transplantation (ASCT) was similar between the Plerixafor Group and the control group, hard to mobilize lymphoma patients had significantly poorer progression-free survival (47% vs. 74% at 36 months after ASCT, p = 0.003) with a trend also to poorer overall survival (71% vs. 84%). In conclusion, while there seem to be no differences in stemness capacity and long-term engraftment efficiency between the Plerixafor and the G-CSF Group in lymphoma as well as myeloma patients, poor mobilizing lymphoma patients per se constitute a high-risk population with a poorer outcome after ASCT. Whether disease characteristics and/or a more intense or stem cell-toxic pre-mobilization chemo-/radiotherapy burden in this cohort are responsible for this observation remains to be shown in future studies.

Autologous and Allogeneic Stem Cell Transplantation as Salvage Treatment Options for Relapsed/Refractory Multiple Myeloma: A Single-center Experience over 20 Years.

BACKGROUND/AIM: Despite multiple treatment options, multiple myeloma (MM) remains an incurable disease with poor outcome. PATIENTS AND METHODS: We retrospectively analyzed the outcome of MM patients undergoing an allogeneic (allo-SCT; n=34) or autologous stem cell transplantation (auto-SCT; n=41) as salvage treatment for relapsed/refractory (r/r) disease. RESULTS: After a median observation period of 79.9 months in the auto group and 15.7 months in the allo group, the 5- and 10-year OS rates were 54% and 44% in the auto group and 17% and 4% in the allo group (p=0.0002), respectively. The 5- and 10-year disease-free survival in the auto group was 21% and 8%, and 14% and 5% in the allo group (p=0.0142), respectively. The 5- and 10-year cumulative incidence of relapse/progression in the auto group was 69% and 82%, and 64% and 69% in the allo group (p=0.0759), respectively. The 5- and 10-year non-relapse mortality in the auto group was significantly lower than that in the allo group [5% versus 45% (p=0.0001)]. CONCLUSION: A second autotransplant in selected r/r patients offers an acceptable long-term outcome partly because of the significantly lower treatment-related morbidity and mortality.

Changing Landscape in the Treatment of Adult Acute Lymphoblastic Leukemia (ALL).

Acute lymphoblastic leukemia (ALL) is a rare hematological malignancy characterized by proliferation and accumulation of premature lymphoid blasts. Depending on risk factors, the survival of acute lymphoblastic leukemia has significantly improved over the last decades. During the last years, measurable residual disease (MRD) assessment has evolved into one of the most sensitive markers for prognosis and risk of relapse. For this reason, measurable residual disease detection and monitoring count as standard evaluation in patients with acute lymphoblastic leukemia. Allogeneic stem cell transplantation is still the recommended treatment option for patients with high and highest risk profiles as well as for relapsed or refractory settings. The increased understanding of the pathomechanism and heterogeneity of acute lymphoblastic leukemia has led to the development of several novel therapeutic opportunities such as tyrosine-kinase inhibitors, antibody-based therapies and CAR-T cells with the aim of improving clinical outcomes. Furthermore, the major advances in disease understanding of ALL have led to the identification of different subgroups and better disease stratification. Even though novel therapy targets are constantly developed, acute lymphoblastic leukemia remains a challenging and life-threatening disease. To improve the historically unsatisfying result in therapy of adult acute lymphoblastic leukemia many clinical trials have recently been initiated to determine the optimum combination regimens of novel and old agents for adult acute lymphoblastic leukemia.

High Mortality of COVID-19 Early after Allogeneic Stem Cell Transplantation: A Retrospective Multicenter Analysis on Behalf of the German Cooperative Transplant Study Group.

Recipients of allogeneic stem cell transplantation (alloSCT) are at high risk for contracting infectious diseases with high morbidity and mortality. Coronavirus disease 2019 (COVID-19) is a viral respiratory disease that can lead to severe pneumonia and acute respiratory distress syndrome, with a potentially fatal outcome. In this retrospective study conducted on behalf of the German Cooperative Transplant Study Group, we aimed to analyze risk factors, disease course, and outcomes of COVID-19 in patients who underwent alloSCT. AlloSCT recipients who became infected with SARS-CoV-2 at German and Austrian transplant centers between February 2020 and July 2021 were included. Classification of COVID-19 severity into mild, moderate-severe, or critical disease and division of the course of the pandemic into 4 phases were done according to the German Robert Koch Institute. The main endpoint was overall mortality at the end of follow-up. We further analyzed the need for treatment in an intensive care unit (ICU) and the severity of disease. Risk factors were evaluated using univariate and multivariate analyses, and survival analysis was performed using Kaplan-Meier method. The study cohort comprised 130 patients from 14 transplant centers, with a median age at diagnosis of COVID-19 of 59 years (range, 20 to 81 years) and a median interval between alloSCT and COVID-19 of 787 days (range, 19 to 8138 days). The most common underlying diseases were acute myeloid leukemia (45.4%) and lymphoma (10.8%). The majority of patients (84.9%) were infected in the later phases of the pandemic; 20.8% had moderate-severe disease, 12.3% had critical disease, and 19.2% were treated in an ICU. After a median follow-up of 127 days, overall mortality was 16.2%, 52.0% among patients treated in an ICU. Risk factors for mortality in multivariate analysis were active disease (odds ratio [OR], 4.46), infection with SARS-CoV-2 ≤365 days after alloSCT (OR, 5.60), age >60 years (OR, 5.39), and ongoing immunosuppression with cyclosporine (OR, 8.55). Risk factors for developing moderate-severe or critical disease were concurrent immunosuppression (OR, 4.06) and age >40 years (OR, 4.08). Patients after alloSCT exhibit a substantially increased mortality risk after COVID-19 infection compared with the normal population, without considerable improvement over the course of the pandemic. Risk factors include age, early infection post-alloSCT, and active immunosuppression. Further studies are needed to improve prevention and treatment in this high-risk patient group.

Rheumatologic diseases impact the risk of progression of MGUS to overt multiple myeloma.

Monoclonal gammopathy of undetermined significance (MGUS), a premalignant condition, is associated with various chronic inflammatory rheumatic diseases (RDs) and is frequently observed as an incidental finding during routine work-up. The association of MGUS and chronic RDs is well established, but the impact of RDs on the risk of transformation into overt multiple myeloma (MM) has not been evaluated so far. MGUS patients diagnosed between January 2000 and August 2016 were identified and screened for concomitant RDs. RDs were grouped into antibody (Ab)-mediated RDs and non-Ab-mediated RDs (polymyalgia rheumatica, large-vessel giant cell arteritis, spondyloarthritis, and gout). Progression to MM was defined as a categorical (yes/no) or continuous time-dependent (time to progression) variable. Of 2935 MGUS patients, 255 (9%) had a concomitant RD. MGUS patients diagnosed with non-Ab-mediated RDs had a doubled risk of progression compared with those without a concomitant RD (hazard ratio, 2.1; 95% CI, 1.1-3.9; P = .02). These data translate into a 5-year risk of progression of 4% in MGUS patients without rheumatologic comorbidity, 10% in those with concomitant non-Ab-mediated RDS, and 2% in those with Ab-mediated RDs. By using the complex risk stratification model that includes myeloma protein (M-protein) concentration, immunoglobulin type, and level of free light chain ratio as variables, patients with non-Ab-mediated RDs (n = 57) had the highest risk for progression (hazard ratio, 6.8; 95% CI, 1.5-30.7; P = .01) compared with patients with Ab-mediated RDs (n = 77). Chronic inflammatory diseases have an impact on the risk of MGUS progressing into overt MM, with a doubled risk of transformation observed in patients with non-Ab-mediated RDs. Future research can elucidate whether comorbidities such as RDs should be included in currently applied prognostic MGUS scores.

The Agony of Choice-Where to Place the Wave of BCMA-Targeted Therapies in the Multiple Myeloma Treatment Puzzle in 2022 and Beyond.

Since the introduction of first-generation proteasome inhibitors and immunomodulatory agents, the multiple myeloma (MM) treatment landscape has undergone a remarkable development. Most recently, immunotherapeutic strategies targeting the B cell maturation antigen (BCMA) entered the clinical stage providing access to highly anticipated novel treatment strategies. At present, numerous different approaches investigate BCMA as an effective multi-modal target. Currently, BCMA-directed antibody-drug conjugates, bispecific and trispecific antibodies, autologous and allogeneic CAR-T cell as well as CAR-NK cell constructs are either approved or in different stages of clinical and preclinical development for the treatment of MM. This armamentarium of treatment choices raises several challenges for clinical decision making, particularly in the absence of head-to-head comparisons. In this review, we provide a comprehensive overview of BCMA-targeting therapeutics, deliver latest updates on clinical trial data, and focus on potential patient selection criteria for different BCMA-targeting immunotherapeutic strategies.

The FMS like Tyrosine Kinase 3 (FLT3) Is Overexpressed in a Subgroup of Multiple Myeloma Patients with Inferior Prognosis.

Therapy resistance remains a major challenge in the management of multiple myeloma (MM). We evaluated the expression of FLT3 tyrosine kinase receptor (FLT3, CD135) in myeloma cells as a possible clonal driver. FLT3 expression was analyzed in bone marrow biopsies of patients with monoclonal gammopathy of undetermined significance or smoldering myeloma (MGUS, SMM), newly diagnosed MM (NDMM), and relapsed/refractory MM (RRMM) by immunohistochemistry (IHC). FLT3 gene expression was analyzed by RNA sequencing (RNAseq) and real-time PCR (rt-PCR). Anti-myeloma activity of FLT3 inhibitors (midostaurin, gilteritinib) was tested in vitro on MM cell lines and primary MM cells by 3H-tymidine incorporation assays or flow cytometry. Semi-quantitative expression analysis applying a staining score (FLT3 expression IHC-score, FES, range 1-6) revealed that a high FES (>3) was associated with a significantly shorter progression-free survival (PFS) in NDMM and RRMM patients (p = 0.04). RNAseq and real-time PCR confirmed the expression of FLT3 in CD138-purified MM samples. The functional relevance of FLT3 expression was corroborated by demonstrating the in vitro anti-myeloma activity of FLT3 inhibitors on FLT3-positive MM cell lines and primary MM cells. FLT3 inhibitors might offer a new targeted therapy approach in a subgroup of MM patients displaying aberrant FLT3 signaling.

Spliced XBP1 Levels Determine Sensitivity of Multiple Myeloma Cells to Proteasome Inhibitor Bortezomib Independent of the Unfolded Protein Response Mediator GRP78.

Background: Mechanisms mediating resistance against the proteasome inhibition by bortezomib (BTZ) in multiple myeloma (MM) cells are still unclear. We analyzed the activation of the unfolded protein response (UPR), induction of prosurvival, and apoptotic pathways after proteasome inhibition in BTZ-sensitive and -resistant cells. Thereafter, these findings from tissue culture were proofed on MM cells of BTZ-sensitive and BTZ-refractory patients. Methods: Proteasomal and ABC transporter activities were measured in sensitive and resistant cell lines by the use of the respective substrates. TP53 gene loss and mutations were determined by cytogenetics and targeted NGS. UPR pathways, proteasome subunit levels and protein secretion were studied by Western Blot analysis, and apoptosis was determined by flow cytometry. MM cell lines were stably transfected with inducible GRP78 expression to study unfolded protein expression. Transient knock-down of GRP78 was done by RNA interference. Splicing of XBP1 and expression of GRP78 was studied by real-time PCR in CD138-enriched MM primary cells of BTZ-refractory and -sensitive patients. Results: BTZ-sensitive cells displayed lower basal proteasomal activities. Similar activities of all three major ABC transporter proteins were detected in BTZ-sensitive and resistant cells. Sensitive cells showed deficiencies in triggering canonical prosurvival UPR provoked by endoplasmic reticulum (ER) stress induction. BTZ treatment did not increase unfolded protein levels or induced GRP78-mediated UPR. BTZ-resistant cells and BTZ-refractory patients exhibited lower sXBP1 levels. Apoptosis of BTZ-sensitive cells was correlating with induction of p53 and NOXA. Tumor cytogenetics and NGS analysis revealed more frequent TP53 deletions and mutations in BTZ-refractory MM patients. Conclusions: We identified low sXBP1 levels and TP53 abnormalities as factors correlating with bortezomib resistance in MM. Therefore, determination of sXBP1 levels and TP53 status prior to BTZ treatment in MM may be beneficial to predict BTZ resistance.