Idecabtagene vicleucel (ide-cel) was the first US Food and Drug Administration-approved chimeric antigen receptor T-cell (CAR-T) therapy for multiple myeloma (MM). However, because clinical trials are highly selective with stringent eligibility criteria, the objective of this study was to evaluate the safety and effectiveness of standard-of-care (SOC) ide-cel in the real world. Using the Center for International Blood and Marrow Transplant Research registry, we evaluated 821 patients who received SOC ide-cel. Median follow-up was 11.6 months. Median age was 66 years, and the cohort included 31% patients aged ≥70 years, with 15% Black and 7% Hispanic, and 77% of patients with ≥1 significant comorbidity. The median number of prior lines of therapy was 7, 15% patients previously received B-cell maturation antigen-directed therapy, 17% had extramedullary disease, and 27% had high-risk cytogenetics. Overall response rate was 73%, and complete response rate was 25%. Median progression-free survival was 8.8 months. Treatment-related mortality was reported in 6% of patients. Cytokine release syndrome was diagnosed in 80% of patients (grade ≥3, 3%). Immune effector cell-associated neurotoxicity syndrome was observed in 28% (grade ≥3, 5%), with no cases of Parkinsonism reported. Clinically significant infections were seen in 45% of patients. Second primary malignancies were reported in 4%, including 1% myeloid malignancies. This is, to our knowledge, the largest real-world study of ide-cel CAR-T therapy in patients with relapsed/refractory (R/R) MM. We observed a favorable safety and efficacy profile that mirrors trial experience, even in the setting of significant comorbidities in 77% of patients, many of which would have made them ineligible for the registrational KarMMa clinical trial. This trial was registered at www.clinicaltrials.gov as #NCT03361748.

Acalabrutinib is a Bruton tyrosine kinase inhibitor approved for treatment of chronic lymphocytic leukemia. We present results from ELEVATE-TN (NCT02475681) after median follow-up of 74.5 months. Overall, 535 patients were randomized (acalabrutinib-obinutuzumab, n = 179; acalabrutinib, n = 179; chlorambucil-obinutuzumab, n = 177). Median age was 70 years, 63.0% had unmutated IGHV (uIGHV), 13.6% had del(17p) and/or mutated TP53, and 17% had complex karyotype (CK; ≥3 chromosomal abnormalities). Median progression-free survival (PFS) was not reached (NR) for acalabrutinib-obinutuzumab and acalabrutinib vs 27.8 months for chlorambucil-obinutuzumab (both P < .0001); estimated 72-month overall PFS rates were 78.0%, 61.5%, and 17.2%, respectively. Acalabrutinib-obinutuzumab resulted in improved PFS vs acalabrutinib monotherapy (hazard ratio [HR]: 0.58, P = .0229). Patients with uIGHV, del(17p) and/or mutated TP53, or CK had significantly improved PFS with acalabrutinib ± obinutuzumab vs chlorambucil-obinutuzumab (P < .0001, P ≤ .0009, and P < .0001 for both acalabrutinib-containing arms, respectively). Median overall survival (OS) was NR for all treatments, with significantly longer OS for acalabrutinib-obinutuzumab vs chlorambucil-obinutuzumab (HR: 0.62, P = .0349). Estimated 72-month OS rates were 83.9%, 75.5%, and 74.7% for acalabrutinib-obinutuzumab, acalabrutinib, and chlorambucil-obinutuzumab, respectively. Adverse events (AEs) occurring after >4 years were mostly grade 1-2. Rates of AEs, serious AEs, and events of clinical interest were similar between acalabrutinib-containing arms and consistent with the known safety profiles of acalabrutinib and obinutuzumab. Efficacy and safety of acalabrutinib-containing arms were maintained, with longer PFS in both acalabrutinib arms vs chlorambucil-obinutuzumab including in patients with high-risk features.

FCARH143, an autologous B-cell maturation antigen (BCMA)-targeted chimeric antigen receptor (CAR) T-cell (CAR-T) therapy, which incorporates a fully human BCMA-specific single chain variable fragment and 4-1BB costimulatory domain, was evaluated in a phase 1 trial for relapsed/refractory multiple myeloma (RRMM). Patients were stratified by bone marrow plasma cell involvement (10%-30% or >30%) and received lymphodepleting chemotherapy followed by escalating CAR-T doses (50 × 106 to 450 × 106). The primary end point was safety; secondary end points were overall response rate (ORR), duration of response, and progression-free survival (PFS). Among 28 enrolled patients, all underwent leukapheresis and successful CAR-T manufacturing, although 3 (11%) did not proceed to infusion. The 25 treated patients (median age, 64 years) had a median of 8 prior therapies, 80% were triple-class refractory, and 44% had extramedullary disease. Cytokine release syndrome occurred in 84% (8% grade 3-4 and no grade 5), and neurotoxicity in 24% (12% grade 3 and no grade 4-5). No treatment-related deaths occurred. At a median follow-up of 67.3 months, treated patients had an ORR of 100%, including a stringent complete response in 64%. Median PFS and overall survival (OS) were 15.5 and 32.1 months, respectively. In an intention-to-treat analysis (median follow-up, 69.6 months), the ORR was 89.3%, and OS was 30.2 months. FCARH143 demonstrated potent antimyeloma activity, with a 100% response rate and manageable toxicity, independent of disease burden or cytogenetic risk. Further evaluation in high-risk RRMM is warranted. This trial was registered at www.clinicaltrials.gov as #NCT03338972.

Lineage switch (LS), defined as the immunophenotypic transformation of acute leukemia, has emerged as a mechanism of relapse after antigen-targeted immunotherapy, which is associated with dismal outcomes. Through an international collaborative effort, we identified cases of LS after a host of antigen-targeted therapies (eg, CD19, CD22, CD38, and CD7), described how LS was diagnosed, reviewed treatment approaches, and analyzed overall outcomes for this form of postimmunotherapy relapse. Collectively, 75 cases of LS were evaluated, including 53 (70.7%) cases of B-cell acute lymphoblastic leukemia (B-ALL) transforming to acute myeloid leukemia (AML), 17 (22.7%) cases of B-ALL transforming to mixed phenotypic acute leukemia (MPAL)/acute leukemias of ambiguous lineage (ALAL), and 5 (6.7%) cases of rare LS presentation (ie, T-cell ALL to AML). An additional 10 cases with incomplete changes in immunophenotype, referred to as "lineage drift" were also described. With a primary focus on the 70 cases of LS from B-ALL to AML or MPAL/ALAL, LS emerged at a median of 1.5 months (range, 0-36.5) after immunotherapy, with 81.4% presenting with LS within the first 6 months from the most proximal immunotherapy. Although most involved KMT2A rearrangements (n = 45, 64.3%), other rare cytogenetic and/or molecular alterations were uniquely observed. Treatment outcomes were generally poor, with remission rates of <40%. The median overall survival after LS diagnosis was 4.8 months. Outcomes were similarly poor for those with rare immunophenotypes of LS or lineage drift. This global initiative robustly categorizes lineage changes after immunotherapy and, through enhanced understanding, establishes a foundation for improving outcomes of LS.

The therapeutic success of first-line quadruplet (QUAD) induction therapy and autologous stem cell transplantation (ASCT) has reinvigorated an interest in fixed-duration therapy, yet optimal short-term efficacy end point for treatment cessation is unknown. Using data from a phase 2 clinical trial and a prospective institutional database, we tested the predictive performance of 5 short-term efficacy end points among 221 patients who received QUAD + ASCT followed by treatment cessation if minimal residual disease (MRD) by next-generation sequencing negative for 2 consecutive time points. Efficacy end points tested were International Myeloma Working Group-defined stringent complete response, MRD <10-5 (single data point), MRD <10-6, sustained MRD (S-MRD; 2 consecutive assessments at least 1 year apart) <10-5, and S-MRD <10-6. We built 5 parallel Cox regression models for each efficacy end point with progression-free survival (PFS) as the outcome. Best fitting models were determined using the Akaike information criterion (AIC) and Heagerty and Zheng C-index. The best fitting model (AIC, 417.2; C statistic, 0.757) was based on S-MRD <10-5 (hazard ratio, 0.23; 95% confidence interval, 0.11-0.47). Similar results were seen for predicting the risk of progression/MRD resurgence among 121 patients undergoing MRD-guided treatment cessation. S-MRD <10-5 is the best predictor of PFS and yields the best predictive models for the risk of MRD resurgence or progression in the setting of fixed-duration therapy. This trial was registered at www.clinicaltrials.gov as #NCT03224507.

Inflammation is increasingly recognized as a critical factor in acute myeloid leukemia (AML) pathogenesis. We performed blood-based proteomic profiling of 251 inflammatory proteins in 543 patients with newly diagnosed AML. Using a machine learning model, we derived an 8-protein prognostic score termed the leukemia inflammatory risk score (LIRS). Individual proteins were evaluated in multivariable Cox models, and model performance was assessed by cumulative concordance index. Findings were validated in internal and external cohorts across 2 institutions. Blood-based LIRS significantly outperformed the European LeukemiaNet 2022 risk model and was independently prognostic of overall survival after accounting for known clinical and molecular prognostic factors. Oncostatin M receptor was uniquely identified as the strongest independent predictor of survival, early mortality, and induction chemotherapy response, and further validated in an independent assay. These blood-based biomarkers could have significant clinical implications for risk stratification and prognostication in patients with newly diagnosed AML.