Tethered IL15-IL15Rα augments antitumor activity of CD19 CAR-T cells but displays long-term toxicity in an immunocompetent lymphoma mouse model.

BACKGROUND: Adoptive cell therapy using genetically modified T cells to express chimeric antigen receptors (CAR-T) has shown encouraging results, particularly in certain blood cancers. Nevertheless, over 40% of B cell malignancy patients experience a relapse after CAR-T therapy, likely due to inadequate persistence of the modified T cells in the body. IL15, known for its pro-survival and proliferative properties, has been suggested for incorporation into the fourth generation of CAR-T cells to enhance their persistence. However, the potential systemic toxicity associated with this cytokine warrants further evaluation. METHODS: We analyzed the persistence, antitumor efficacy and potential toxicity of anti-mouse CD19 CAR-T cells which express a membrane-bound IL15-IL15Rα chimeric protein (CD19/mbIL15q CAR-T), in BALB/c mice challenged with A20 tumor cells as well as in NSG mice. RESULTS: Conventional CD19 CAR-T cells showed low persistence and poor efficacy in BALB/c mice treated with mild lymphodepletion regimens (total body irradiation (TBI) of 1 Gy). CD19/mbIL15q CAR-T exhibits prolonged persistence and enhanced in vivo efficacy, effectively eliminating established A20 B cell lymphoma. However, this CD19/mbIL15q CAR-T displays important long-term toxicities, with marked splenomegaly, weight loss, transaminase elevations, and significant inflammatory findings in some tissues. Mice survival is highly compromised after CD19/mbIL15q CAR-T cell transfer, particularly if a high TBI regimen is applied before CAR-T cell transfer. CONCLUSION: Tethered IL15-IL15Rα augments the antitumor activity of CD19 CAR-T cells but displays long-term toxicity in immunocompetent mice. Inducible systems to regulate IL15-IL15Rα expression could be considered to control this toxicity.

Immune dysfunction prior to and during vaccination in multiple myeloma: a case study based on COVID-19.

Infection is the leading cause of death in multiple myeloma (MM). However, the cellular composition associated with immune dysfunction is not defined. We analyzed immune profiles in the peripheral blood of patients with MM (n = 28) and B-cell chronic lymphoproliferative disorders (n = 53) vs. health care practitioners (n = 96), using multidimensional and computational flow cytometry. MM patients displayed altered distribution of most cell types (41/56, 73%), particularly within the B-cell (17/17) and T-cell (20/30) compartments. Using COVID-19 as a case study, we compared the immune response to vaccination based on 64,304 data points generated from the analysis of 1099 longitudinal samples. MM patients showed limited B-cell expansion linked to lower anti-RBD and anti-S antibody titers after the first two doses and booster. The percentages of B cells and CD4+ T cells in the blood, as well as the absolute counts of B cells and dendritic cells, predicted vaccine immunogenicity at different time points. In contrast with the humoral response, the percentage and antigen-dependent differentiation of SARS-CoV-2-specific CD8+ T cells was not altered in MM patients. Taken together, this study defined the cellular composition associated with immune dysfunction in MM and provided biomarkers such as the B-cell percentage and absolute count to individualize vaccination calendars.

Practical Aspects of Immunotherapy: A Report from the 20th International Myeloma Society (IMS) Annual Meeting.

Immunotherapeutic strategies, specifically T-cell-redirected therapies, have been transformative in the context of multiple myeloma (MM). With the approval of two chimeric antigen receptor T-cell (CAR-T) drug products and three bispecific antibodies/T-cell engagers (bsAbs/TCEs) in relapsed/refractory MM (RRMM), the 20th annual IMS meeting dedicated a session to the practical aspects of these therapies. Here, we highlight the discussion during this session, including the role of CAR-T and bsAb therapies in frontline MM treatment, management of acute toxicities, prevention and management of infections, and finally treatment sequencing of T-cell redirected therapies.

Round Table Discussion on Optimal Clinical Trial Design in Precursor Multiple Myeloma.

SUMMARY: While the current approach to precursor hematologic conditions is to "watch and wait," this may change with the development of therapies that are safe and extend survival or delay the onset of symptomatic disease. The goal of future therapies in precursor hematologic conditions is to improve survival and prevent or delay the development of symptomatic disease while maximizing safety. Clinical trial considerations in this field include identifying an appropriate at-risk population, safety assessments, dose selection, primary and secondary trial endpoints including surrogate endpoints, control arms, and quality-of-life metrics, all of which may enable more precise benefit-risk assessment.

Selinexor, daratumumab, bortezomib and dexamethasone for the treatment of patients with relapsed or refractory multiple myeloma: results of the phase II, nonrandomized, multicenter GEM-SELIBORDARA study.

The treatment landscape for multiple myeloma has significantly evolved in the last decade. Notwithstanding, a large proportion of patients continue to relapse and novel combinations continue to be needed. In this phase II study, selinexor, a first-in-class inhibitor of exportin-1 was evaluated in combination with standard daratumumab-bortezomib-dexamethasone (DVd), for the treatment of relapsed and refractory multiple myeloma (RRMM). The aim of the trial was to assess the efficacy and safety of the combination of selinexor with DVd (S-DVd). A total of 57 patients were enrolled in the two parts of the study. Part 1 enrolled a heavily pretreated population with at least three prior lines (PL) of therapy and part 2 enrolled an early relapse population with at least one PL of therapy. The primary endpoint was complete response (CR) rate in part 2 and overall response rate (ORR) in part 1. In the latter, 24 patients were treated with a median of three PL. Overall response rate (ORR) was 50% with two CR. Median progression- free survival (PFS) was 7 months. In part 2, 33 patients were enrolled, with a median of one PL. ORR was 82% and CR or better was 33%. Median PFS was 24 months. In lenalidomide-refractory patients, a median PFS of 22.1 months was observed. Thrombocytopenia was the most common hematological adverse event (69%; grade 3-4: 34%) and nausea, the most frequent non-hematological adverse event (38%; grade 3-4: 6%). Sixty-two percent of the patients required dose modifications. In summary, although the primary endpoint of the study was not met, the combination of S-DVd showed encouraging clinical efficacy with a generally manageable safety profile representing a potential option for the treatment of RRMM patients.

Quantification of cyclin D1 and D2 proteins in multiple myeloma identifies different expression patterns from those revealed by gene expression profiling.

Upregulation of a cyclin D gene determined by expression microarrays is an almost universal event in multiple myeloma (MM), but this finding has not been properly confirmed at the protein level. For this reason, we carried out a quantitative analysis of cyclin D proteins using a capillary electrophoresis nanoimmunoassay in newly diagnosed MM patients. Exclusive expression of cyclin D1 and D2 proteins was detected in 54 of 165 (33%) and 30 of 165 (18%) of the MM patients, respectively. Of note, cyclin D1 or D2 proteins were undetectable in 41% of the samples. High levels of cyclin D1 protein were strongly associated with the presence of t(11;14) or 11q gains. Cyclin D2 protein was detected in all the cases bearing t(14;16), but in only 24% of patients with t(4;14). The presence of cyclin D2 was associated with shorter overall survival (hazard ratio =2.14; P=0.017), although patients expressing cyclin D2 protein, but without 1q gains, had a favorable prognosis. In conclusion, although one of the cyclins D is overexpressed at the mRNA level in almost all MM patients, in approximately half of the patients this does not translate into detectable protein. This suggests that cyclins D could not play an oncogenic role in a proportion of patients with MM (clinicaltrials gov. identifier: NCT01916252).

Teclistamab Improves Patient-Reported Symptoms and Health-Related Quality of Life in Relapsed or Refractory Multiple Myeloma: Results From the Phase II MajesTEC-1 Study.

INTRODUCTION: Patients with relapsed or refractory multiple myeloma (RRMM) report significantly lower HRQoL compared with patients with newly diagnosed MM and experience further deterioration in HRQoL with each relapse and subsequent treatment. Therefore, consideration of the impact of treatment on HRQoL in addition to clinical outcomes is vital. PATIENTS AND METHODS: In the phase I/II MajesTEC-1 (NCT03145181, NCT04557098) study, patients with RRMM who received teclistamab, an off-the-shelf, T-cell redirecting BCMA × CD3 bispecific antibody, had deep and durable responses with manageable safety. HRQoL was assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire core 30-item and the EuroQol 5 Dimension 5 Level descriptive questionnaire. Changes over time from baseline were measured with a repeated measures mixed-effects model. Proportions of patients with clinically meaningful improvement after starting treatment and time to clinically meaningful worsening were assessed. RESULTS: Compliance was maintained throughout the study. Compared with baseline, positive changes were observed for pain, global health status, and emotional functioning with treatment; other assessments were largely unchanged from baseline. Post hoc analysis showed patients with deeper clinical response generally reported improved HRQoL outcomes. Following an initial decline in HRQoL in some scales, the proportion of patients reporting clinically meaningful improvements increased, while the proportion reporting clinically meaningful worsening decreased over time. Clinically meaningful improvements in pain were reported in ≥40% of patients at most assessment time points. CONCLUSIONS: These results complement previously reported clinical benefits and support teclistamab as a promising therapeutic option for patients with RRMM.

Predictors of unsustained measurable residual disease negativity in transplant-eligible patients with multiple myeloma.

ABSTRACT: The role of measurable residual disease (MRD) negativity as a biomarker to stop treatment is being investigated in transplant-eligible patients with multiple myeloma (MM). Thus, it is important to identify risk factors of MRD resurgence and/or progressive disease (PD) among patients achieving undetectable MRD to avoid undertreating them. Here, we studied 267 newly diagnosed transplant-eligible patients with MM enrolled in the GEM2012MENOS65 and GEM2014MAIN clinical trials who achieved MRD negativity by next-generation flow cytometry. After a median follow-up of 73 months since the first MRD negative assessment, 111 of the 267 (42%) patients showed MRD resurgence and/or PD. The only prognostic factors at diagnosis that predicted MRD resurgence and/or PD were an International Staging System (ISS) 3 and the presence of ≥0.01% circulating tumor cells (CTCs). Failure to achieve MRD negativity after induction also predicted higher risk of MRD resurgence and/or PD. Patients having 0 vs 1 vs ≥2 risk factors (ISS 3, ≥0.01% CTCs, and late MRD negativity) showed 5-year rates of MRD resurgence and/or PD of 16%, 33%, and 57%, respectively (P < .001). Thus, these easily measurable risk factors could help refine the selection of patients for whom treatment cessation after MRD negativity is being investigated in clinical trials. This trial was registered at www.clinicaltrials.gov as NCT01916252 and NCT02406144.

Recovery of uninvolved heavy/light chain pair immunoparesis in newly diagnosed transplant-eligible myeloma patients complements the prognostic value of minimal residual disease detection.

Immunoparesis (IP) in multiple myeloma (MM) patients can be measured by classic assessment of immunoglobulin (Ig) levels or by analysis of the uninvolved heavy/light chain pair of the same immunoglobulin (uHLC) by the Hevylite® assay. In this study we evaluate the prognostic value of recovery from IP measured by classic total Ig and uHLC assessment in newly diagnosed MM transplant-eligible (NDMM-TE) patients with intensive treatment and its association with Minimal Residual Disease (MRD). Patients were enrolled and treated in the PETHEMA/GEM2012MENOS65 trial and continued in the PETHEMA/GEM2014MAIN trial. Total Ig (IgG, IgA and IgM) and uHLC were analyzed in a central laboratory at diagnosis, after consolidation treatment and after the first year of maintenance. MRD was analyzed by next generation flow cytometry after consolidation (sensitivity level 2x10-6). We found no differences in progression free survival (PFS) between patients who recovered and patients who didn't recover from IP after consolidation when examining classic total Ig and uHLC. However, after the first year of maintenance, in contrast to patients with classic IP, patients with recovery from uHLC IP had longer PFS than patients without recovery, with hazard ratio of 0.42 (CI95% 0.21-0.81; p=0.008). Multivariate analysis with Cox proportional-hazards regression models confirmed recovery from uHLC IP after the first year of maintenance as an independent prognostic factor for PFS, with an increase in C-statistic of 0.05 (-0.04-0.14; p<0.001) when adding uHLC IP recovery. Moreover, we observed that MRD status and uHLC IP recovery affords complementary information for risk stratification. In conclusion, recovery from uHLC IP after one year of maintenance is an independent prognostic factor for PFS in NDMM-TE patients who receive intensive treatment. Immune reconstitution, measured as recovery from uHLC IP, provides complementary prognostic information to MRD assessment.

Integrated analysis of randomized controlled trials evaluating bortezomib + lenalidomide + dexamethasone or bortezomib + thalidomide + dexamethasone induction in transplant-eligible newly diagnosed multiple myeloma.

Objective: Providing the most efficacious frontline treatment for newly diagnosed multiple myeloma (NDMM) is critical for patient outcomes. No direct comparisons have been made between bortezomib + lenalidomide + dexamethasone (VRD) and bortezomib + thalidomide + dexamethasone (VTD) induction regimens in transplant-eligible NDMM. Methods: An integrated analysis was performed using patient data from four trials meeting prespecified eligibility criteria: two using VRD (PETHEMA GEM2012 and IFM 2009) and two using VTD (PETHEMA GEM2005 and IFM 2013-04). Results: The primary endpoint was met, with VRD demonstrating a noninferior rate of at least very good partial response (≥ VGPR) after induction vs VTD. GEM comparison demonstrated improvement in the ≥ VGPR rate after induction for VRD vs VTD (66.3% vs 51.2%; P = .00281) that increased after transplant (74.4% vs 53.5%). Undetectable minimal residual disease rates post induction (46.7% vs 34.9%) and post transplant (62.4% vs 47.3%) support the benefit of VRD vs VTD. Treatment-emergent adverse events leading to study and/or treatment discontinuation were less frequent with VRD (3%, GEM2012; 6%, IFM 2009) vs VTD (11%, IFM 2013-04). Conclusion: These results supported the benefit of VRD over VTD for induction in transplant-eligible patients with NDMM. The trials included are registered with ClinicalTrials.gov (NCT01916252, NCT01191060, NCT00461747, and NCT01971658).

Large T cell clones expressing immune checkpoints increase during multiple myeloma evolution and predict treatment resistance.

Tumor recognition by T cells is essential for antitumor immunity. A comprehensive characterization of T cell diversity may be key to understanding the success of immunomodulatory drugs and failure of PD-1 blockade in tumors such as multiple myeloma (MM). Here, we use single-cell RNA and T cell receptor sequencing to characterize bone marrow T cells from healthy adults (n = 4) and patients with precursor (n = 8) and full-blown MM (n = 10). Large T cell clones from patients with MM expressed multiple immune checkpoints, suggesting a potentially dysfunctional phenotype. Dual targeting of PD-1 + LAG3 or PD-1 + TIGIT partially restored their function in mice with MM. We identify phenotypic hallmarks of large intratumoral T cell clones, and demonstrate that the CD27- and CD27+ T cell ratio, measured by flow cytometry, may serve as a surrogate of clonal T cell expansions and an independent prognostic factor in 543 patients with MM treated with lenalidomide-based treatment combinations.

Time-Dependent Prognostic Value of Serological and Measurable Residual Disease Assessments after Idecabtagene Vicleucel.

The role of measurable residual disease (MRD) in multiple myeloma patients treated with chimeric antigen receptor (CAR) T cells is uncertain. We analyzed MRD kinetics during the first year after idecabtagene vicleucel (ide-cel) infusion in 125 relapsed/refractory multiple myeloma patients enrolled in KarMMa. At month 1 after ide-cel, there were no differences in progression-free survival (PFS) between patients in less than complete response (CR) versus those in CR; only MRD status was predictive of significantly different PFS at this landmark. In patients with undetectable MRD at 3 months and beyond, PFS was longer in those achieving CR versus

Lenalidomide and dexamethasone maintenance with or without ixazomib, tailored by residual disease status in myeloma.

From November 2014 to May 2017, 332 patients homogeneously treated with bortezomib, lenalidomide, and dexamethasone (VRD) induction, autologous stem cell transplant, and VRD consolidation were randomly assigned to receive maintenance therapy with lenalidomide and dexamethasone (RD; 161 patients) vs RD plus ixazomib (IRD; 171 patients). RD consisted of lenalidomide 15 mg/d from days 1 to 21 plus dexamethasone 20 mg/d on days 1 to 4 and 9 to 12 at 4-week intervals, whereas in the IRD arm, oral ixazomib at a dose of 4 mg on days 1, 8, and 15 was added. Therapy for patients with negative measurable residual disease (MRD) after 24 cycles was discontinued, whereas those who tested positive for MRD remained on maintenance with RD for 36 more cycles. After a median follow-up of 69 months from the initiation of maintenance, the progression-free survival (PFS) was similar in both arms, with a 6-year PFS rate of 61.3% and 55.6% for RD and IRD, respectively (hazard ratio, 1.136; 95% confidence interval, 0.809-1.603). After 2 years of maintenance, treatment was discontinued in 163 patients with negative MRD, whereas 63 patients with positive MRD continued with RD therapy. Maintenance discontinuation in patients tested negative for MRD resulted in a low progression rate (17.2% at 4 years), even in patients with high-risk features. In summary, our results show the efficacy of RD maintenance and support the safety of maintenance therapy discontinuation in patients with negative MRD at 2 years. This trial was registered at www.clinicaltrials.gov as #NCT02406144 and at EudraCT as 2014-00055410.

Management of multiple myeloma-related renal impairment: recommendations from the International Myeloma Working Group.

Here, the International Myeloma Working Group (IMWG) updates its clinical practice recommendations for the management of multiple myeloma-related renal impairment on the basis of data published until Dec 31, 2022. All patients with multiple myeloma and renal impairment should have serum creatinine, estimated glomerular filtration rate, and free light chains (FLCs) measurements together with 24-h urine total protein, electrophoresis, and immunofixation. If non-selective proteinuria (mainly albuminuria) or involved serum FLCs value less than 500 mg/L is detected, then a renal biopsy is needed. The IMWG criteria for the definition of renal response should be used. Supportive care and high-dose dexamethasone are required for all patients with myeloma-induced renal impairment. Mechanical approaches do not increase overall survival. Bortezomib-based regimens are the cornerstone of the management of patients with multiple myeloma and renal impairment at diagnosis. New quadruplet and triplet combinations, including proteasome inhibitors, immunomodulatory drugs, and anti-CD38 monoclonal antibodies, improve renal and survival outcomes in both newly diagnosed patients and those with relapsed or refractory disease. Conjugated antibodies, chimeric antigen receptor T-cells, and T-cell engagers are well tolerated and effective in patients with moderate renal impairment.

Cilta-cel or Standard Care in Lenalidomide-Refractory Multiple Myeloma.

BACKGROUND: Ciltacabtagene autoleucel (cilta-cel), a B-cell maturation antigen (BCMA)-directed CAR T-cell therapy, is effective in heavily pretreated patients with relapsed or refractory multiple myeloma. We investigated cilta-cel in earlier treatment lines in patients with lenalidomide-refractory disease. METHODS: In this phase 3, randomized, open-label trial, we assigned patients with lenalidomide-refractory multiple myeloma to receive cilta-cel or the physician's choice of effective standard care. All the patients had received one to three previous lines of treatment. The primary outcome was progression-free survival. RESULTS: A total of 419 patients underwent randomization (208 to receive cilta-cel and 211 to receive standard care). At a median follow-up of 15.9 months (range, 0.1 to 27.3), the median progression-free survival was not reached in the cilta-cel group and was 11.8 months in the standard-care group (hazard ratio, 0.26; 95% confidence interval [CI], 0.18 to 0.38; P<0.001). Progression-free survival at 12 months was 75.9% (95% CI, 69.4 to 81.1) in the cilta-cel group and 48.6% (95% CI, 41.5 to 55.3) in the standard-care group. More patients in the cilta-cel group than in the standard-care group had an overall response (84.6% vs. 67.3%), a complete response or better (73.1% vs. 21.8%), and an absence of minimal residual disease (60.6% vs. 15.6%). Death from any cause was reported in 39 patients and 46 patients, respectively (hazard ratio, 0.78; 95% CI, 0.5 to 1.2). Most patients reported grade 3 or 4 adverse events during treatment. Among the 176 patients who received cilta-cel in the as-treated population, 134 (76.1%) had cytokine release syndrome (grade 3 or 4, 1.1%; no grade 5), 8 (4.5%) had immune effector cell-associated neurotoxicity syndrome (all grade 1 or 2), 1 had movement and neurocognitive symptoms (grade 1), 16 (9.1%) had cranial nerve palsy (grade 2, 8.0%; grade 3, 1.1%), and 5 (2.8%) had CAR-T-related peripheral neuropathy (grade 1 or 2, 2.3%; grade 3, 0.6%). CONCLUSIONS: A single cilta-cel infusion resulted in a lower risk of disease progression or death than standard care in lenalidomide-refractory patients with multiple myeloma who had received one to three previous therapies. (Funded by Janssen and Legend Biotech; CARTITUDE-4 ClinicalTrials.gov number, NCT04181827.).

Prevention and management of adverse events during treatment with bispecific antibodies and CAR T cells in multiple myeloma: a consensus report of the European Myeloma Network.

T-cell redirecting bispecific antibodies (BsAbs) and chimeric antigen receptor T cells (CAR T cells) have revolutionised multiple myeloma therapy, but adverse events such as cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome (ICANS), cytopenias, hypogammaglobulinaemia, and infections are common. This Policy Review presents a consensus from the European Myeloma Network on the prevention and management of these adverse events. Recommended measures include premedication, frequent assessing for symptoms and severity of cytokine release syndrome, step-up dosing for several BsAbs and some CAR T-cell therapies; corticosteroids; and tocilizumab in the case of cytokine release syndrome. Other anti-IL-6 drugs, high-dose corticosteroids, and anakinra might be considered in refractory cases. ICANS often arises concomitantly with cytokine release syndrome. Glucocorticosteroids in increasing doses are recommended if needed, as well as anakinra if the response is inadequate, and anticonvulsants if convulsions occur. Preventive measures against infections include antiviral and antibacterial drugs and administration of immunoglobulins. Treatment of infections and other complications is also addressed.