Deficiencies in cluster-2 ALA lipid flippases result in salicylic acid-dependent growth reductions.

P4 ATPases (i.e., lipid flippases) are eukaryotic enzymes that transport lipids across membrane bilayers. In plants, P4 ATPases are named Aminophospholipid ATPases (ALAs) and are organized into five phylogenetic clusters. Here we generated an Arabidopsis mutant lacking all five cluster-2 ALAs (ala8/9/10/11/12), which is the most highly expressed ALA subgroup in vegetative tissues. Plants harboring the quintuple knockout (KO) show rosettes that are 2.2-fold smaller and display chlorotic lesions. A similar but less severe phenotype was observed in an ala10/11 double KO. The growth and lesion phenotypes of ala8/9/10/11/12 mutants were reversed by expressing a NahG transgene, which encodes an enzyme that degrades salicylic acid (SA). A role for SA in promoting the lesion phenotype was further supported by quantitative PCR assays showing increased mRNA abundance for an SA-biosynthesis gene ISOCHORISMATE SYNTHASE 1 (ICS1) and two SA-responsive genes PATHOGENESIS-RELATED GENE 1 (PR1) and PR2. Lesion phenotypes were also reversed by growing plants in liquid media containing either low calcium (~0.1 mM) or high nitrogen concentrations (~24 mM), which are conditions known to suppress SA-dependent autoimmunity. Yeast-based fluorescent lipid uptake assays revealed that ALA10 and ALA11 display overlapping substrate specificities, including the transport of LysoPC signaling lipids. Together, these results establish that the biochemical functions of ALA8-12 are at least partially overlapping, and that deficiencies in cluster-2 ALAs result in an SA-dependent autoimmunity phenotype that has not been observed for flippase mutants with deficiencies in other ALA clusters.

Development and Validation of a Prediction Model of Outcome After B-Cell Maturation Antigen-Directed Chimeric Antigen Receptor T-Cell Therapy in Relapsed/Refractory Multiple Myeloma.

PURPOSE: Although chimeric antigen receptor T therapy (CAR-T) cells are an established therapy for relapsed/refractory multiple myeloma (RRMM), there are no established models predicting outcome to identify patients who may benefit the most from CAR-T. PATIENTS AND METHODS: This is an international retrospective observational study including patients with RRMM infused with currently available commercial or academically produced anti-B-cell maturation antigen (BCMA) CAR-T. We describe characteristics and outcomes in Europe (n = 136) and the United States (n = 133). Independent predictors of relapse/progression built a simple prediction model (Myeloma CAR-T Relapse [MyCARe] model) in the training cohort (Europe), which was externally validated (US cohort) and tested within patient- and treatment-specific subgroups. RESULTS: The overall response rate was 87% and comparable between both cohorts, and complete responses were seen in 48% (Europe) and 49% (the United States). The median time to relapse was 5 months, and early relapse <5 months from infusion showed poor survival across cohorts, with the 12-month overall survival of 30% (Europe) and 14% (the United States). The presence of extramedullary disease or plasma cell leukemia, lenalidomide-refractoriness, high-risk cytogenetics, and increased ferritin at the time of lymphodepletion were independent predictors of early relapse or progression. Each factor received one point, forming the three-tiered MyCARe model: scores 0-1 (low risk), scores 2-3 (intermediate risk), and a score of 4 (high risk). The MyCARe model was significantly associated with distinct 5-month incidence of relapse/progression (P < .001): 7% for low-risk, 27% for intermediate-risk, and 53% for high-risk groups. The model was validated in the US cohort and maintained prognostic utility for response, survival, and outcomes across subgroups. CONCLUSION: Outcomes of patients with RRMM after CAR-T are comparable between Europe and the United States. The MyCARe model may facilitate optimal timing of CAR-T cells in patient-specific subgroups.

Efficacy and safety of daratumumab, pomalidomide, and dexamethasone versus daratumumab, carfilzomib, and dexamethasone in daratumumab-naïve relapsed multiple myeloma.

OBJECTIVES AND METHODS: We conducted a multicenter retrospective study to analyze the safety and efficacy of DPd versus DKd in daratumumab naïve RRMM patients treated in real-world practice. RESULTS: A total of 187 patients with RRMM were included in the analysis; 128 patients received DPd, and 59 patients received DKd. A vast majority (80%) of patients had lenalidomide refractory disease and nearly 50% had bortezomib refractory disease. The overall response and complete response rates were 76% and 34% in the DPd group versus 80% and 51% in the DKd group, respectively. With a median follow up of 36 months for the entire patient population, median PFS and OS in the DPd versus DKd groups were 12, 12, 37, and 35 months, respectively. The most common grade 3+ adverse events in the DPd versus DKd groups were neutropenia (32% vs. 7%), anemia (14% vs. 10%), thrombocytopenia (13% vs. 15%), and cardiovascular events (4% vs. 15%), respectively. Both DPd and DKd appeared to be a safe and effective treatment options for RRMM. CONCLUSIONS: While there were more cytopenias associated with DPd and more cardiovascular side effects with DKd, there were no significant differences in the survival outcomes with these two regimens.

Efficacy and safety of idecabtagene vicleucel in patients with relapsed-refractory multiple myeloma not meeting the KarMMa-1 trial eligibility criteria: A real-world multicentre study.

Ide-cel received approval for relapsed-refractory multiple myeloma based on the results of the KarMMa-1 trial. However, patients with significant comorbidities, aggressive disease and prior B-cell maturation antigen-directed therapy (BCMA-DT) were excluded. This retrospective study evaluated real-world outcomes of patients who did not meet the KarMMa-1 eligibility criteria and were treated with standard of care (SOC) ide-cel. A total of 69 patients from three US centres who did not meet the KarMMa-1 criteria underwent ide-cel infusion. The main reasons for trial ineligibility included baseline grade 3-4 cytopenia (39%), prior BCMA-DT (26%), renal impairment (19%) and Eastern Cooperative Oncology Group performance status ≥2 (14.5%). Cytokine-release syndrome occurred in 81% vs. 84%, and immune effector cell-associated neurotoxicity syndrome occurred in 28% vs. 18% of SOC versus KarMMa-1 patients, respectively. Early infection (≤8 weeks post-infusion) and severe infection rates were 42% vs. 49% and 30% vs. 22% for the SOC versus KarMMa-1 cohorts, respectively. Grade 3-4 cytopenias for SOC versus KarMMa-1 cohorts were: neutropenia (87% vs. 89%), anaemia (51% vs. 60%) and thrombocytopenia (65% vs. 52%). Overall response rate was higher for the SOC cohort (93% vs. 73%), as was the complete response or better rate (48% vs. 33%). However, median progression-free survival and overall survival were comparable between the two groups. Our findings support broadening the inclusion criteria of future trials evaluating ide-cel.

Impact of age, obesity, and renal impairment on outcomes after autologous stem cell transplantation for patients with newly diagnosed multiple myeloma.

INTRODUCTION: There remains a need to determine whether certain subgroups of newly diagnosed multiple myeloma (NDMM) derive the same benefit from high-dose chemotherapy-autologous stem cell transplant (HDT-ASCT). We describe our institutional experience highlighting the impact of age, obesity, and renal impairment on outcomes after HDT-ASCT for patients with NDMM in a real-world setting. METHODS: A total of 449 consecutive patients were included in this retrospective analysis. RESULTS: No difference in median progression free survival or overall survival was seen for patients with age > 65, body mass index (BMI) > 30 kg/m2, or estimated glomerular filtration rate < 60 mL/min/1.73 m2 when compared to those without these characteristics. From a safety standpoint, there were no differences in the incidence of transplant-related mortality or secondary malignancy among subgroups. CONCLUSION: For patients with NDMM undergoing HDT-ASCT, there is no difference in outcomes based on age, BMI, or renal function, and the presence of one or more of these factors should not preclude patients from HDT-ASCT.

Early versus standard management of chimeric antigen receptor therapy toxicities and management's impact on safety and efficacy.

BACKGROUND: Cytokine release syndrome (CRS) and immune effector cell-associated neurologic syndrome (ICANS) are well-documented toxicities of CAR T-cell therapy. To mitigate excessive toxicity, our center has formulated treatment protocols (early vs. standard) for timely management of CRS and ICANS with tocilizumab and/or corticosteroids. METHODS: This retrospective, single-center analysis included patients treated with CAR T-cell therapy. The goal was to describe the association of two management protocols with toxicity and efficacy outcomes. RESULTS: Fifty-five percent of the 40 patients assigned to early management, out of which 5% and 9% developed grade 3+ CRS and ICANS, respectively. Seventy-seven percent and 41% of these patients received tocilizumab and corticosteroids, respectively. Forty-five percent of patients were stratified as standard management, out of which 0% and 11% developed grade 3+ CRS and ICANS, respectively. Seventeen percent and 28% of these patients received tocilizumab and corticosteroids, respectively. The day +90 overall response rate (ORR) for all patients was 63%, with an ORR of 89% for those managed per early management versus 50% for those managed per standard protocol. CONCLUSION: Early use of tocilizumab and corticosteroids is effective in preventing excessive CAR-T-related toxicities with no negative impact on efficacy.

Impact of race and ethnicity on outcomes after autologous stem cell transplantation for patients with newly diagnosed multiple myeloma.

Non-Hispanic Black patients are disproportionally affected by multiple myeloma (MM) and whether efficacy outcomes after autologous stem cell transplant (ASCT) differ by race and ethnicity remains an area of active investigation. This study included 449 patients enriched with a large proportion of non-Hispanic Black patients and sought to highlight the impact of race and ethnicity on outcomes after HDT-ASCT for patients with newly diagnosed MM. We found induction chemotherapy followed by high-dose therapy-ASCT and maintenance chemotherapy is associated with long-term PFS and OS, regardless of race or ethnicity.

Idecabtagene vicleucel chimeric antigen receptor T-cell therapy for relapsed/refractory multiple myeloma with renal impairment.

We evaluated patients with relapsed multiple myeloma with renal impairment (RI) treated with standard of care idecabtagene vicleucel (ide-cel), as outcomes with chimeric antigen receptor (CAR) T-cell therapy are unknown in this population. RI was defined as creatinine clearance (CrCl) <50 mL/min. CrCl of <30 mL/min or dialysis dependence were defined as severe RI. The study cohort included 214 patients, 28 (13%) patients with RI, including 11 patients severe RI (dialysis, N=1). Patients with RI were older, more likely to be female and had higher likelihood of having Revised International Staging System stage 3 disease. Rates and severity of cytokine release syndrome (89% vs. 84%, grade ≥3: 7% vs. 2%) and immune effector cell-associated neurotoxicity syndrome (23% vs. 20%) were similar in patients with and without RI, respectively. Patients with RI had higher incidence of short-term grade ≥3 cytopenias, although cytopenias were similar by 3 months following CAR T-cell therapy. Renal function did not worsen after CAR T-cell therapy in patients with RI. Response rates (93% vs. 82%) and survival outcomes (median progression-free survival: 9 vs. 8 months; P=0.26) were comparable in patients with and without RI, respectively. Treatment with ide-cel is feasible in patients with RI, with a comparable safety and efficacy profile as patients without RI, with notable exception of higher short-term high-grade cytopenias.

Racial and ethnic differences in clinical outcomes among patients with multiple myeloma treated with CAR T-cell therapy.

ABSTRACT: Idecabtagene vicleucel (ide-cel) was the first chimeric antigen receptor T-cell therapy to gain US Food and Drug Administration approval for patients with relapsed/refractory multiple myeloma (RRMM). The clinical outcomes of standard of care (SOC) ide-cel in racially and ethnically diverse populations have been understudied. This study pooled data from 207 patients with RRMM (28% patients of racial and ethnic minority groups) treated with SOC ide-cel across 11 institutions to examine racial and ethnic differences in the incidence of toxicities and adverse events, response to ide-cel, and survival. This study included 22 (11%) Hispanic, 36 (17%) non-Hispanic Black, and 149 (72%) non-Hispanic White patients with RRMM. Compared with Hispanic and non-Hispanic White patients, non-Hispanic Black patients had higher median levels of C-reactive protein (1.0, 0.8, and 3.5 mg/dL, respectively; P = .02) and baseline ferritin (362.0 vs 307.0 vs 680.5, respectively; P = .08) and were more likely to develop cytokine release syndrome (77%, 85%, and 97%, respectively; P = .04). Although best overall response rate was lower among Hispanic patients (59%) than among non-Hispanic Black (86%) and White patients (86%; P = .01), there were no racial and ethnic differences in progression-free or overall survival. We provide, to our knowledge, the first and largest investigation of clinical outcomes of SOC ide-cel by race and ethnicity. Despite differences in safety and response to ide-cel, our findings encourage the use of ide-cel in all patients with RRMM. These findings should be confirmed in larger samples of diverse patients with RRMM, with longer follow-up time.

Safety and efficacy of eltrombopag in patients with post-CAR T cytopenias.

BACKGROUND: While chimeric antigen receptor (CAR) T-cell therapy has revolutionized the treatment outcomes of relapsed/refractory hematological malignancies, this therapy is associated with post-treatment cytopenias, which can pose a challenge to its safe administration. This study describes the management of post-CAR T cytopenias using the thrombopoietin mimetic eltrombopag. METHODS: This retrospective analysis included adult patients with lymphoma or myeloma who received CAR T-cell therapy at two academic medical centers. Eltrombopag was initiated for patients who had persistent high-grade leukopenia and/or thrombocytopenia beyond 21 days post-CAR T infusion. Risk factors and outcomes were assessed and compared for patients who did or did not receive eltrombopag. RESULTS: Among the 185 patients analyzed, a majority (88%) experienced thrombocytopenia or leukopenia at day +30 post-CAR T infusion. A total of 42 patients met the criteria for eltrombopag treatment and initiated therapy. Patients who received eltrombopag were more likely to have pre-existing cytopenias at lymphodepletion, receive bridging therapy, experience an infection, or require intensive care. Recovery from cytopenias occurred within 180 days for a majority (94%) of patients. CONCLUSIONS: The use of eltrombopag for post-CAR T leukopenia and thrombocytopenia was considered safe without any significant toxicities. The use of eltrombopag for post-CAR T cytopenias might be effective in a high-risk patient population but requires further study.

Impact of Frailty on Outcomes after Chimeric Antigen Receptor T Cell Therapy for Patients with Relapsed/Refractory Multiple Myeloma.

The literature is limited regarding outcomes in older adults and frail patients receiving BCMA-directed chimeric antigen receptor T cell therapy (CAR-T) for relapsed or refractory multiple myeloma. Here we describe the safety and efficacy of CAR-T in these clinically important subgroups treated in a real-world setting. Frailty was defined as a frail score ≥2 using the simplified frailty index (score based on age + Eastern Cooperative Oncology Group [ECOG] Performance Status + Hematopoietic Cell Transplantation Comorbidity Index [HCT-CI]). Of the 136 patients analyzed (age range, 41 to 81 years), 83 (61%) were considered frail at the time of CAR-T infusion. Compared to the nonfrail group, the frail group had higher proportions of patients with renal insufficiency (18% versus 6%), high-risk cytogenetics (45% versus 35%), extramedullary disease (51% versus 43%), and ECOG Performance Status ≥2 (18% versus 2%), and worse HCT-CI (3 versus 1). Although patients in the frail group had a higher incidence of immune effector cell-associated neurotoxicity syndrome (ICANS) (39% versus 17%), the incidences of all- grade cytokine release syndrome (CRS), as well as high-grade CRS and ICANS, were similar in the 2 groups. With a median follow-up of 7 months, the median progression-free survival was 6.9 months in the frail group versus 11.1 months in the nonfrail group (P = .028). The median overall survival was 14 months in the frail group and was not reached in the nonfrail group (P = .025). This study highlights the tolerable safety and reasonable efficacy of CAR-T for frail myeloma patients in a real-world practice. Although the frail patients did not experience any excessive high-grade toxicities, they did have inferior efficacy outcomes.

Safety and Efficacy of Teclistamab in Patients with Relapsed/Refractory Multiple Myeloma: A Real-World Experience.

Teclistamab is a B cell maturation antigen (BCMA)-directed bispecific antibody approved for relapsed/refractory multiple myeloma (RRMM) on the basis of the phase I/II MajesTEC-1 trial. Here we report clinical outcomes with standard-of-care teclistamab in a real-world RRMM population. A total of 106 patients from 5 academic centers who received teclistamab from August 2022 to August 2023 were included in this retrospective analysis, 83% of whom would have been considered ineligible for the MajesTEC-1 trial. All patients were triple-class exposed, 64% were penta-class refractory, and 53% had received prior BCMA-directed therapy. Cytokine release syndrome was observed in 64% of patients, and only 1 event was grade ≥3, whereas immune effector cell-associated neurotoxicity syndrome was observed in 14% of patients (3 events were grade 3 or 4). One-third (31%) of patients experienced at least 1 infection, with nearly half of these infections graded as severe (grade ≥3). The overall response rate (ORR) was 66%, and the complete or better response rate was 29%. The ORR was 47% for patients with extramedullary disease (EMD), 59% for patients with prior BCMA-directed therapy exposure, and 68% for patients with penta-refractory disease. At a median follow-up of 3.8 months, the median progression-free survival (PFS) was 5.4 months (95% CI, 3.4 months to not reached), while median overall survival was not reached. Patients with Eastern Cooperative Oncology Group Performance Status ≥2, EMD, and age ≤70 years had inferior PFS on multivariable analysis. Our study demonstrates reasonable safety and good efficacy of teclistamab in patients with RRMM treated in a real-world setting.

Real-world experience of patients with multiple myeloma receiving ide-cel after a prior BCMA-targeted therapy.

Most patients with multiple myeloma experience disease relapse after treatment with a B-cell maturation antigen-targeted therapy (BCMA-TT), and data describing outcomes for patients treated with sequential BCMA-TT are limited. We analyzed clinical outcomes for patients infused with standard-of-care idecabtagene vicleucel, an anti-BCMA chimeric antigen receptor (CAR) T-cell therapy, at 11 US medical centers. A total of 50 patients with prior BCMA-TT exposure (38 antibody-drug conjugate, 7 bispecific, 5 CAR T) and 153 patients with no prior BCMA-TT were infused with ide-cel, with a median follow-up duration of 4.5 and 6.0 months, respectively. Safety outcomes between cohorts were comparable. The prior BCMA-TT cohort had a lower overall response rate (74% versus 88%; p = 0.021), median duration of response (7.4 versus 9.6 months; p = 0.03), and median progression-free survival (3.2 months versus 9.0 months; p = 0.0002) compared to the cohort without prior BCMA-TT. All five patients who received a prior anti-BCMA CAR T responded to ide-cel, and survival outcomes were best for this subgroup. In conclusion, treatment with ide-cel yielded meaningful clinical responses in real-world patients exposed to a prior BCMA-TT, though response rates and durability were suboptimal compared to those not treated with a prior BCMA-TT.