High-risk Cytogenetic Abnormalities Research Articles

Long-term remission and survival in patients with relapsed or refractory multiple myeloma after treatment with LCAR-B38M CAR T cells: 5-year follow-up of the LEGEND-2 trial

BackgroundThe autologous anti–B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell therapy LCAR-B38M has been approved for the treatment of relapsed and refractory multiple myeloma in many countries across the world under the name ciltacabtagene autoleucel. LEGEND-2 was the first-in-human trial of LCAR-B38M and yielded deep and durable therapeutic responses. Here, we reported the outcomes in LEGEND-2 after a minimal 5-year follow-up.MethodsParticipants received an average dose of 0.5 × 106 cells/kg LCAR-B38M in split or single unfractionated infusions after cyclophosphamide-based lymphodepletion therapy. Investigator-assessed response, survival, safety and pharmacokinetics were evaluated.ResultsSeventy-four participants enrolled and had a median follow-up of 65.4 months. The 5-year progression-free survival (PFS) and overall survival (OS) rates were 21.0% and 49.1%, with progressive flattening of the survival curves over time. Patients with complete response (CR) had longer PFS and OS, with 5-year rates of 28.4% and 65.7%, respectively. Twelve patients (16.2%) remained relapse-free irrespective of baseline high-risk cytogenetic abnormality and all had normal humoral immunity reconstituted. An ongoing CR closely correlated with several prognostic baseline indices including favorable performance status, immunoglobulin G subtype, and absence of extramedullary disease, as well as a combination cyclophosphamide and fludarabine preconditioning strategy. Sixty-two (83.8%) suffered progressive disease (PD) and/or death; however, 61.1% of PD patients could well respond to subsequent therapies, among which, the proteasome inhibitor-based regimens benefited the most. Concerning the safety, hematologic and hepatic function recovery were not significantly different between non-PD and PD/Death groups. A low rate of second primary malignancy (5.4%) and no severe virus infection were observed. The patients who tested positive for COVID-19 merely presented self-limiting symptoms. In addition, a sustainable CAR T population of one case with persistent remission was delineated, which was enriched with indolently proliferative and lowly cytotoxic CD4/CD8 double-negative functional T lymphocytes.ConclusionsThese data, representing the longest follow-up of BCMA-redirected CAR T-cell therapy to date, demonstrate long-term remission and survival with LCAR-B38M for advanced myeloma.Trial registrationLEGEND-2 was registered under the trial numbers NCT03090659, ChiCTRONH-17012285.

Daratumumab-based quadruplet therapy for transplant-eligible newly diagnosed multiple myeloma with high cytogenetic risk

In the MASTER study (NCT03224507), daratumumab+carfilzomib/lenalidomide/dexamethasone (D-KRd) demonstrated promising efficacy in transplant-eligible newly diagnosed multiple myeloma (NDMM). In GRIFFIN (NCT02874742), daratumumab+lenalidomide/bortezomib/dexamethasone (D-RVd) improved outcomes for transplant-eligible NDMM. Here, we present a post hoc analysis of patients with high-risk cytogenetic abnormalities (HRCAs; del[17p], t[4;14], t[14;16], t[14;20], or gain/amp[1q21]). Among 123 D-KRd patients, 43.1%, 37.4%, and 19.5% had 0, 1, or ≥2 HRCAs. Among 120 D-RVd patients, 55.8%, 28.3%, and 10.8% had 0, 1, or ≥2 HRCAs. Rates of complete response or better (best on study) for 0, 1, or ≥2 HRCAs were 90.6%, 89.1%, and 70.8% for D-KRd, and 90.9%, 78.8%, and 61.5% for D-RVd. At median follow-up (MASTER, 31.1 months; GRIFFIN, 49.6 months for randomized patients/59.5 months for safety run-in patients), MRD-negativity rates as assessed by next-generation sequencing (10–5) were 80.0%, 86.4%, and 83.3% for 0, 1, or ≥2 HRCAs for D-KRd, and 76.1%, 55.9%, and 61.5% for D-RVd. PFS was similar between studies and superior for 0 or 1 versus ≥2 HRCAs: 36-month PFS rates for D-KRd were 89.9%, 86.2%, and 52.4%, and 96.7%, 90.5%, and 53.5% for D-RVd. These data support the use of daratumumab-containing regimens for transplant-eligible NDMM with HCRAs; however, additional strategies are needed for ultra-high–risk disease (≥2 HRCAs).Video 935yYg7rG1hc1uCFy66-b8

A real-world retrospective-prospective analysis of efficacy and safety of combined ixazomib, lenalidomide, and dexamethasone in relapsed/refractory multiple myeloma: The northern Italy experience.

Ixazomib, lenalidomide, and dexamethasone (IRd) have been approved for the treatment of relapsed/refractory multiple myeloma (RRMM) based on the results of the TOURMALINE-MM1. We conducted a retrospective-prospective analysis of 106 RRMM patients (pts) treated with IRd in 21 centers in Northern Italy, with the aim to evaluate the efficacy and safety of IRd in real life. At IRd initiation, 34% of pts were aged ≥75 (median 72.5), 8.5% had an ECOG performance status ≥2, 54.7% of evaluable pts carried high-risk cytogenetic abnormalities [del17p and/or t(4;14) and/or t(14;16) and/or 1 g gain/amp], 60.2% had received ≥2 prior lines of therapy (pLoT), 57.5% were lenalidomide (Len)-exposed (including both Len-sensitive and Len-refractory pts), and 22% were Len-refractory. Main G ≥3 adverse events (AEs) were thrombocytopenia (16%) and neutropenia (12.3%). G ≥3 non-hematologic AEs included infections (9.4%) and GI toxicity (diarrhea 5.7%, hepatotoxicity 2.8%), VTE, skin rash, and peripheral neuropathy were mainly G1-2. The overall response rate was 56.4% (≥VGPR 30%). With a median follow-up of 38 m, median PFS (mPFS) was 16 m and the 1-year OS rate was 73%. By subgroup analysis, an extended PFS was observed for pts achieving ≥VGPR (mPFS 21.2 m), time from diagnosis to IRd ≥5 years (26.2 m), 1 pLoT (34.4 m), Len-naïve (NR), age ≥70 (20 m). In pts exposed to Len, non-refractory in any prior line and immediately prior to IRd, mPFS was 16 and 18 m, respectively. An inferior PFS was seen in Len-refractory pts (4.6 m). By multivariate analysis, independent predictors of PFS were age ≥70 (HR 0.6), time from diagnosis ≥5 years (HR 0.32), refractoriness to Len in any prior line (HR 3.33), and immediately prior (HR 4.31). IRd might be effective and safe in RRMM pts with an indolent disease, in early lines of treatment, and who proved Len-sensitive, independent of age, and cytogenetic risk.

Efficacy of daratumumab in newly diagnosed multiple myeloma patients with 1q21 gain.

Gain and amplification of 1q21 (1q21+) are adverse chromosomal aberrations of multiple myeloma (MM) that lead to refractoriness to a variety of therapies. While it is known that daratumumab, an anti-cancer monoclonal antibody, cannot overcome the disadvantage of 1q21+in relapsed/refractory MM patients, its benefit in newly diagnosed MM (NDMM) patients with 1q21+has not been clarified. We retrospectively evaluated 11 (55%) 1q21+patients (3 copies: 6, > 4 copies: 5) among 20 NDMM patients (median age, 74years) who received daratumumab-containing regimens at Shibukawa Medical Center from October 2019 to October 2022. The overall response rate was 82% for patients with 1q21+and 78% for patients without 1q21+. Median progression-free survival (PFS) and median overall survival (OS) were not reached in either group. Neither 1q21 copy number nor co-existence of other high-risk cytogenetic abnormalities significantly affected PFS or OS. Our preliminary data suggests that outcomes of daratumumab treatment in NDMM 1q21+patients might be non-inferior to those in non-1q21+patients.

The frequency and clinical outcome of mono-hit and multi-hit TP53 aberrations in newly diagnosed multiple myeloma

We investigated the frequency and outcome of mono-hit and multi-hit TP53 aberrations [biallelic or ≥1 TP53 mutations (TP53mut) or TP53mut with variant allele frequency (VAF) ≥55%] in an Indian cohort of newly diagnosed multiple myeloma (NDMM) patients. We employed fluorescence insitu hybridisation (FISH; n=457) and targeted next-generation sequencing (NGS; n=244) on plasma cell-enriched samples. We also studied the impact of TP53mut in cases with and without TP53 deletions (TP53del). In our cohort with a median age of 60 years, TP53del and TP53mut were seen in 12.9% (n=59/457; 14-95% cells) and 10.2% (n=25/244; 30 variants; VAF 3.4-98.2%; median 38.2%) respectively. Mono-hit and multi-hit-TP53 aberrations were observed in 10.2% and 7.8%, respectively. Compared to TP53-wild-type (TP53wt), mono-hit and multi-hit TP53 aberrations were associated with significantly poorer progression-free survival (PFS) (22.6 vs 12.1 vs 9.5 months; p=0.004) and overall survival (OS) [not reached (NR) vs 13.1 vs 15.6 months respectively; p=0.024]. However, multi-hit TP53 did not significantly differ in OS/PFS compared to mono-hit cases. Compared to TP53wt, PFS and OS were significantly poorer in patients with TP53mut only (9.5 vs 22.6 months and 12.1 months vs NR, respectively; p=0.020/0.004). TP53mut retained its significance even in the presence of any Revised International Staging System (HR 2.1; 95% CI 1.1-3.8; p=0.015) for OS. The detection of additional cases with TP53 aberrations, as well as poor survival associated with the presence of mutation alone, supports TP53mut testing in NDMM at least in patients without TP53del and other high-risk cytogenetic abnormalities.

Alterations in chromosome 1q in multiple myeloma randomized clinical trials: a systematic review

Extra copies of chromosome 1q21 (+1q: gain = 3 copies, amp >= 4 copies) are associated with worse outcomes in multiple myeloma (MM). This systematic review assesses the current reporting trends of +1q, the efficacy of existing regimens on +1q, and its prognostic implications in MM randomized controlled trials (RCTs). Pubmed, Embase and Cochrane Registry of RCTs were searched from January 2012 to December 2022. Only MM RCTs were included. A total of 124 RCTs were included, of which 29 (23%) studies reported on +1q. Among them, 10% defined thresholds for +1q, 14% reported survival data separately for gain and amp, and 79% considered +1q a high-risk cytogenetic abnormality. Amongst RCTs that met the primary endpoint showing improvement in progression free survival (PFS), lenalidomide maintenance (Myeloma XI), selinexor (BOSTON), and isatuximab (IKEMA and ICARIA) were shown to improve PFS for patients with evidence of +1q. Some additional RCT’s such as Myeloma XI+ (carfilzomib), ELOQUENT-3 (elotuzumab), and HOVON-65/GMMG-HD4 (bortezomib) met their endpoint showing improvement in PFS and also showed improvement in PFS in the +1q cohort, although the confidence interval crossed 1. All six studies that reported HR for +1q patients vs. without (across both arms) showed worse OS and PFS for +1q. There is considerable heterogeneity in the reporting of +1q. All interventions that have shown to be successful in RCTs and have clearly reported on the +1q subgroup have shown concordant direction of results and benefit of the applied intervention. A more standardized approach to reporting this abnormality is needed.

1q21+ is associated with poor prognosis in newly diagnosed multiple myeloma patients with extramedullary disease: a retrospective study.

1q21+ is a common cytogenetic abnormality in multiple myeloma (MM) and is considered an independent predictor of poor prognosis; however, its impact on extramedullary disease (EMD) remains unknown. Our study reviewed the clinical relevance and prognostic value of 1q21+ status in 92 patients with NDMM and EMD. 1q21+ was detected in 23.9% (22/92) of patients. Patients with 1q21+ presented with advanced International Staging System stages (P = 0.006), lower level of hemoglobin (P = 0.004), higher percentage of plasma cells in the bone marrow (P < 0.001), higher level of serum β2-microglobulin (7.24g/L vs. 3.85g/L, P = 0.003), and higher levels of lactic dehydrogenase (LDH) (206.5 U/L vs. 177 U/L, P = 0.019). The prevalence of soft tissue-related EMD (EMD-S) (54.5% vs. 18.6%, P < 0.001), renal dysfunction (50.5% vs. 17.7%, P = 0.002), and hypercalcemia (27.3% vs. 7.1%, P = 0.011) was also higher. 1q21+ was strongly associated with other high-risk cytogenetic abnormalities, including IgH/FGFR3 (22.7% vs. 4.3%, P = 0.007) and IgH/MAF translocations (22.7% vs. 1.4%, P < 0.001). 1q21+ patients had significantly shorter overall survival (OS) and progression-free survival (PFS) (OS: 24months vs. 47months, P = 0.002; PFS: 14months vs. 38months, P < 0.001); the poor survival outcomes could not be reversed by autologous hematopoietic stem cell transplantation. Multivariate analysis suggested that 1q21+ , EMD-S, elevated lactate dehydrogenase (LDH) levels, and P53 deletion were independent risk factors for poor prognosis in patients with EMD. In patients with 1q21+ EMD, hypercalcemia, elevated LDH levels, and P53 deletion were independent adverse risk prognostic factors.

Outcomes of patients with multiple myeloma and 1q gain/amplification receiving autologous hematopoietic stem cell transplant: the MD Anderson cancer center experience

The prognostic impact of additional copies of chromosome 1q (1q + ) on outcomes of newly-diagnosed multiple myeloma (NDMM) patients undergoing autologous transplantation (autoSCT) is unclear. We conducted a retrospective single-center analysis of NDMM patients with 1q21 gain/amplification (3 or ≥4 copies of 1q, respectively) that received autoSCT between 2008–2018. 213 patients were included (79% 1q gain; 21% 1q amplification). The most commonly used induction regimen was bortezomib, lenalidomide, and dexamethasone (41%). At day100 post-autoSCT and at best post-transplant response, 78% and 87% of patients achieved ≥VGPR, and 38% and 50% achieved MRD-negative ≥VGPR, respectively. Median PFS and OS for the entire cohort were 35.5 months and 81.4 months, respectively. On multivariable assessment for PFS, MRD negative ≥VGPR before autoSCT (HR 0.52, p = 0.013) was associated with superior PFS, whereas 1q amplification was associated with inferior PFS (2.03, p = 0.003). On multivariate analysis for OS, achieving MRD negative ≥VGPR at best post-transplant response was associated with superior survival (0.29, p < 0.001), whereas R-ISS III and concomitant del17p or t(4:14) were associated with inferior survival (6.95, p = 0.030, 2.33, p = 0.023 and 3.00, p = 0.047, respectively). In conclusion, patients with 1q+ NDMM, especially 1q amplification, have inferior survival outcomes compared to standard-risk disease after upfront autoSCT, though outcomes are better than other high-risk cytogenetic abnormalities.

Complex karyotype determined using conventional cytogenetic analysis is a poor prognostic factor in patients with multiple myeloma.

High-risk cytogenetic abnormalities (HRCAs) influence the prognosis of multiple myeloma (MM). However, additional cytogenetic aberrations can lead to poor outcomes. This study aimed to clarify whether HRCAs and additional chromosomal abnormalities affect MM prognosis. Patients with newly diagnosed MM who were treated with novel agents were retrospectively evaluated. The primary objective was to assess the difference in progression-free survival (PFS) and overall survival (OS) between patients with/without HRCAs and between patients with/without complex karyotype (CK). The secondary objectives were to identify factors affecting PFS/OS and factors related to CK. HRCAs were defined as del(17p), t(4;14), t(14;16), and gain/amplification(1q) assessed using fluorescence in situ hybridization. CK was defined as ≥3 chromosomal abnormalities on G-banding. Among 110 patients, 40 had HRCAs and 15 had CK. In this study, survival durations between patients with/without HRCAs were similar, while the CK group had significantly poorer PFS/OS than the no-CK group (median PFS: 9 vs. 24 months and median OS: 29 vs. 97 months, respectively), and a poor prognostic impact of CK was maintained in patients with HRCAs. In multivariate analysis, CK was correlated with poor PFS/OS (hazard ratio [HR]: 2.39, 95% confidence interval [95% CI]: 1.22-4.66 and HR: 2.66, 95% CI: 1.10-6.45, respectively). Bone marrow plasma cell (BMPC) ≥60% (odds ratio [OR] = 6.40, 95% CI: 1.50-27.2) and Revised International Staging System III (OR = 7.53, 95% CI: 2.09-27.1) were associated with CK. Our study suggests that CK may contribute to the poor prognosis of MM. Aggressive disease status including high BMPC proliferation could be relevant to CK.

Impact of pretransplant minimal residual disease in patients with multiple myeloma and a very good partial response or better receiving autologous hematopoietic stem cell transplantation.

The prognostic significance of minimal residual disease (MRD) status before autologous hematopoietic stem cell transplantation (autoHCT) in patients with multiple myeloma (MM) has not been clearly elucidated. Retrospective single-center study of adult MM patients who achieved ≥very good partial response (VGPR) after induction therapy from 2015 to 2021 received upfront autoHCT and had available pretransplant MRD status by next-generation flow cytometry. The cohort was divided into pretransplant MRD-negative (MRDneg) and MRD-positive (MRDpos) groups. A total of 733 patients were included in our analysis; 425 were MRDneg and 308 MRDpos at autoHCT. In the MRDpos group, more patients had high-risk cytogenetic abnormalities (48% vs. 38%, respectively; p=.025), whereas fewer patients achieved ≥CR before autoHCT (14% vs. 40%; p<.001). At day 100 after autoHCT, 37% of the MRDpos versus 71% of the MRDneg achieved ≥CR, and at best posttransplant response 65% versus 88% achieved ≥CR, respectively. After a median follow-up of 27.6months (range, 0.7-82.3), the median PFS was significantly shorter for patients in the MRDpos group compared to the MRDneg group: 48.2months (95% confidence interval [CI], 0.3-80.5) versus 80.1months (95% CI, 0.5-80.1), respectively (p<.001). There was no significant difference in overall survival between the two groups (p=.41). Pretransplant MRDpos status was predictive of shorter PFS in multivariate analysis (hazard ratio, 1.80; 95% CI, 1.31-2.46; p<.001). The impact of pretransplant MRD status was retained in most of the examined subgroups. In patients achieving ≥VGPR to induction, pretransplant MRDpos status was associated with a lower CR rate after autoHCT and a shorter PFS.

Predictors of unsustained measurable residual disease negativity in patients with multiple myeloma

AbstractThe prognostic impact of achieving and in particular maintaining measurable residual disease (MRD) negativity in multiple myeloma is now established; therefore, identifying among MRD-negative patients the ones at higher risk of losing MRD negativity is of importance. We analyzed predictors of unsustained MRD negativity in patients enrolled in the FORTE trial (NCT02203643). MRD was performed by multiparameter flow cytometry (sensitivity of 10−5) at premaintenance and every 6 months thereafter. The cumulative incidence (CI) of MRD resurgence and/or progression was analyzed in MRD-negative patients. A total of 306 of 474 (65%) MRD-negative patients were analyzed. After a median follow-up of 50.4 months from MRD negativity, 185 of 306 (60%) patients were still MRD negative and progression free, 118 (39%) lost their MRD-negative status, and 3 patients (1%) died without progression. Amp1q vs normal (4-year CI, 63% vs 34), ≥2 concomitant high-risk cytogenetic abnormalities vs 0 (4-year CI, 59% vs 33%), circulating tumor cells at baseline (high vs low at 4-year CI, 62% vs 32%), and time-to-reach MRD negativity postconsolidation vs preconsolidation (4-year CI, 46% vs 35%) were associated with a higher risk of unsustained MRD negativity in a multivariate Fine-Gray model. During the first 2 years of maintenance, patients receiving carfilzomib-lenalidomide vs lenalidomide alone had a lower risk of unsustained MRD negativity (4-year CI, 20% vs 33%).

Impact of Cytogenetic Abnormalities, Induction and Maintenance Regimens on Outcomes After High-Dose Chemotherapy and Autologous Stem Cell Transplantation in Patients With Newly Diagnosed Multiple Myeloma: A Decade-Long Real-World Experience.

High-dose chemotherapy and autologous stem cell transplant (HDT-ASCT) has become a standard of care for transplant eligible newly diagnosed multiple myeloma (NDMM) patients. While cytogenetic abnormalities have been shown to affect outcomes after HDT-ASCT in clinical trials, these trials often exclude or underrepresent elderly patients with comorbidities and those belonging to ethnic minorities. We describe our institutional experience highlighting the impact of high-risk cytogenetic abnormalities (HRCAs) on outcomes after HDT-ASCT for NDMM patients. A total of 449 patients with NDMM who underwent HDT-ASCT between February 2012 and August 2022 were included in this retrospective analysis. HRCAs included the presence of one or more of: deletion 17p, t(14;16), t(4;14), and amplification 1q. Survival analyses, including progression-free survival (PFS) and overall survival (OS), were performed using Kaplan-Meier estimator. With a median follow-up of 29 (1 - 128) months for the entire patient population, the best overall response rate for the patients with HRCAs was lower compared to those with standard risk cytogenetics (90% vs. 96%; P = 0.01). Patients with HRCAs had an inferior PFS compared to patients with standard-risk cytogenetics (29 vs. 58 months; P < 0.001) without a difference in OS (70 months vs. not reached; P = 0.13). In a multivariable analysis adjusting for factors including age, race, and comorbidities, HRCAs, non-lenalidomide-based maintenance, non-proteasome inhibitor-based maintenance, and age greater than 65 were associated with inferior PFS. Amongst these factors, only non-lenalidomide-based maintenance was associated with inferior OS.

Efficacy of different regimens and prognostic factors in patients with first relapsed multiple myeloma treated after front-line bortezomib, cyclophosphamide, and dexamethasone

Objective: To analyze the efficacy of second-line regimens and prognostic factors in patients with first-relapsed multiple myeloma (MM) treated with bortezomib, cyclophosphamide, and dexamethasone (BCD). Methods: A retrospective cohort study. Clinical data were collected in first-relapsed MM patients after BCD treatment from three tertiary hospitals in north China from July 2009 to October 2022. Patients were classified according to the second-line regimen into the immunotherapy group, single novel agent group [either proteasome inhibitor (PI) or immunomodulatory drug (IMiD)], combination treatment group (both PI+IMiD), and traditional treatment group. Responses to second-line regimens and survival data were analyzed. The Kaplan-Meier method was used for survival analysis and the Cox proportional risk model was used for univariate and multivariate analyses. Results: A total of 217 patients were enrolled including 8.8% (19/217) in the immunotherapy group, 48.4% (105/217) in the PI/IMiD group, 29.9% (65/217) in the PI+IMiD group, and 12.9% (28/217) in the traditional treatment group. The median age was 62 years (range 31-83 years) and 56.2% (122/217) were males. The overall response rates (ORRs) in the four groups were 94.7% (18/19) vs. 56.2% (59/105) vs. 73.8% (48/65) vs. 32.1% (9/28) (χ2=24.55; P<0.001), respectively. The progression-free survival (PFS) of the second-line regimens (2ndPFS) was 17.7 vs. 9.0 vs. 9.2 vs. 4.6 months (χ2=22.74; P<0.001), respectively, among which patients in the PI/IMiD and PI+IMiD groups had comparable 2ndPFS (χ2=1.76; P=0.923). Patients with high-risk cytogenetic abnormalities (HRCAs) achieved the longest 2ndPFS of 22.0 months in the immunotherapy group (χ2=15.03; P=0.002). Multivariate analysis suggested that immunotherapy (HR=0.11, 95%CI 0.05-0.27), achievement of efficacy of partial response or better (HR=0.47, 95%CI 0.34-0.66), and non-aggressive relapse (HR=0.25, 95%CI 0.17-0.37) were independent prognostic factors of 2ndPFS. Conclusion: In this real-world study, immunotherapy was associated with a more favorable efficacy and PFS for first-relapsed MM patients after BCD treatment, with similar outcomes in patients with HRCAs.

Abstract B114: Population differences in the associations between chromosomal abnormalities and overall survival among Blacks and Whites with multiple myeloma

Abstract Background: Several primary and secondary cytogenetic abnormalities (e.g., translocation t(4;14) and 1q copy number changes) are associated with poor prognosis and worse survival of multiple myeloma (MM). Some of the aberrations (e.g., t(11;14), t(14;16), and t(14;20)) have been suggested, albeit inconclusively, to be enriched in Blacks. However, whether the associations between chromosomal abnormalities and overall survival (OS) of MM differ by race/ethnicity remains largely unknown. Methods: We prospectively enrolled 586 patients with newly diagnosed MM between 2010-2019 at the University of Chicago Medical Center. Of the 561 subjects identified as Black or White, 181 had chromosomal abnormalities determined by fluorescence in situ hybridization (FISH), which used CD138+ plasma cells enriched from bone marrow aspirates collected within 180 days of diagnosis. We analyzed data for 19 aberrations, including IGH/FGFR3 fusion [t(4;14)(p16,q32)]; IGH/CCND1 fusion [t(11;14)(q13,q32)]; IGH/MAF [t(14;16)(q32,q23)]; IGH/MAFB [t(14;20)(q32,q12)]; trisomies of chromosome 3, 7, 9, and 12; chromosome 13 deletion; loss of ATM [11q22.3]; gain of ATM; loss of TP53 [17p13.1]; gain of TP53; loss of CDKN2C [1p32.3]; gain of CKS1B [1q21]; IGH translocation with uncommon chromosome partners; IGH locus rearrangement; loss of IGH; and tetraploidy. Vital status was ascertained using the National Death Index. Baseline clinical and laboratory data were retrieved from electronic medical records. We used proportions and Chi-square tests to compare the distributions of cytogenetic abnormalities in Blacks and Whites. In each population, we evaluated the associations between cytogenetic abnormalities and OS using hazard ratios (HRs) and 95% confidence interval (CIs) from Cox proportional hazards models, adjusting for prognostic factors including age, international staging system, elevated lactate dehydrogenase, and estimated glomerular filtration rate. We used the Wald test of the cross-product terms to assess potential heterogeneity of effect in the HRs by race. Results: Of the 181 MM patients, 55 (30.39%) were Black and 126 (69.61%) were White. The median follow-up was 69 months. The frequencies of the 19 cytogenetic abnormalities did not differ between Blacks and Whites. However, we observed population differences in the associations between two chromosomal abnormalities and OS: the presence of t(4;14) was associated with worse OS in Blacks (HR=14.34 [2.17-94.58]; N=38) but not Whites (HR=2.04 [0.70-5.88]; N=99, p-heterogeneity = 0.08), whereas gain of 1q was associated with poorer OS in Whites (HR: 3.38, 95% CI: [1.25- 9.09], N=77), but not Blacks (HR=1.32 [0.31-5.68]; N=32; p-heterogeneity=0.02). Conclusions: Although we found similar frequencies of primary and secondary chromosomal abnormalities between Blacks and Whites, our data show population differences in the associations between two established high-risk cytogenetic abnormalities and the OS of MM. Our findings suggest that cytogenetic features may have varying impacts on the OS of MM based on race. Citation Format: Bei Wang, Benjamin A. Derman, Jason Cheung, Wei Zhang, Andrzej Jakubowiak, Brian C. Chiu. Population differences in the associations between chromosomal abnormalities and overall survival among Blacks and Whites with multiple myeloma [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B114.

Efficacy of Daratumumab-Based Regimens in Anti-CD38 Treatment-Naïve Relapsed/Refractory Multiple Myeloma with High-Risk Cytogenetics

Background: Daratumumab-based combination with proteasome inhibitors (PI) and immunomodulatory drugs (IMiDs) have revolutionized the treatment outcomes of relapsed/refractory multiple myeloma (RRMM). Several daratumumab-based triplet combinations have been approved for the management of RRMM, but outcomes of daratumumab-based triplets in patients with high-risk cytogenetics RRMM (HC-RRMM) are not well described in the literature. This study aimed to evaluate the clinical outcome of daratumumab-based regimens in patients with HC-RRMM who are daratumumab-naïve. Methods: A retrospective review of 110 patients with HC-RRMM who received daratumumab-containing regimens from 6/2016 through 2/2023 at the University of Kansas Medical Center, in collaboration with the U.S Myeloma Innovations Research Collaborative (USMIRC) was conducted. Daratumumab was combined with bortezomib/dexamethasone (DVd), carfilzomib/dexamethasone (DKd), and pomalidomide/dexamethasone (DPd) for treatment of RRMM. HC-RRMM was defined as patients with one or more cytogenetic abnormalities (on FISH panel) including -17/del(17p), t(4;14), t(14;16), t(14;20), or amplification of 1q. Responses to therapy including overall response rate (ORR), complete response or better (≥CR), and very good partial response (VGPR) were evaluated using the International Myeloma Working Group (IMWG) criteria. Descriptive statistics were used to summarize patient and disease characteristics, along with efficacy outcomes. Progression-free survival (PFS) and overall survival (OS) were calculated by Kaplan-Meier methods. Results: Of the 110 patients with HC-RRMM, the median age was 66 years (range 43-84), 83 (75%) were Caucasian, 60 (54%) had IgG isotype, 41 (37%) had revised international staging system (R-ISS) stage III disease, 35 (32%) had extramedullary disease (EMD), 57 (52%) patients had one high-risk cytogenetic (HC) abnormality, 49 (44%) had 2 HC abnormalities, while four (4%) had 3 HC abnormalities. The median number of previous lines of therapy was 2 (1-4). Eighty-eight patients (80%) were lenalidomide refractory, while 53 patients (48%) had double refractory disease to both a PI and IMiD treatment. A total of 19 (17%), 27 (25%), and 64 (58%) patients received DVd, DKd, and DPd, respectively. The overall response rate (ORR) for the entire patient population was 73%, 45% had VGPR or better, and 35% achieved ≥CR. Median follow-up was 28 months (12.07-53.57), the median OS was 28 months (95% CI 23.2 - 43.9) and PFS was 8.03 months (95% CI 5.8 - 12.2) for all treatment groups. The median PFS for 1 HC vs ³ 2 HC was 14.8 vs 4.57 months (HR 1.72, 95%CI 1.17-2.72 p = 0.006), respectively. Similarly, median OS for 1 HC vs ³ 2 HC was 43.93 vs 22.47 months (HR 1.87, 95%CI 1.15-3.05, p = 0.011), respectively. (Figure 1). On multivariate analysis, R-ISS stage III, -17/del(17p), and the presence of more than one HC abnormality were associated with poor OS. The most common cause for treatment discontinuation was progressive disease, accounting for 73% of patients in the whole cohort. As for each daratumumab-based triplet, discontinuation due progression occurred in 78%, 48%, and 83% in DVd, DKd, and DPd, respectively. Other causes of discontinuation included &amp;gt; grade 3 neuropathy, which occurred in 16% of patients receiving DVd, and cardiac events, which occurred in 11% of patients receiving DKd. Treatment-related mortality occurred in 2% of patients in the whole cohort. At the time of evaluation, 14 patients remain on treatment. Conclusion: Advanced stage R-ISS disease at diagnosis, presence of -17/del(17p), and 2 or more HC abnormalities were associated with poor prognosis reflected by worse PFS and OS in HC-RRMM treated with daratumumab-based therapies. A larger cohort or a prospective study in patients with HC-RRMM is needed to compare long-term outcomes between daratumumab-based therapies (DKd, DVd, and DPd).

Carfilzomib, Lenalidomide and Dexamethasone (KRd) As Induction Therapy in High-Risk Newly Diagnosed Multiple Myeloma

Background: Carfilzomib, lenalidomide and dexamethasone (KRd) has been shown to be an effective induction regimen for newly diagnosed myeloma (NDMM), particularly in myeloma with high-risk (HR) features in the FORTE trial (Mina et al, Lancet Onc 2023). Here, we present a retrospective analysis in patients with HR NDMM in a real-world population from two high-volume centers, highlighting efficacy and survival outcomes in high-risk subgroups to gain a better understanding of the utility of this regimen in clinical practice. Methods: We conducted a retrospective study of patients with HR NDMM treated with KRd at Memorial Sloan Kettering (MSK) and Winship Cancer Institute from 1/1/2015 to 9/30/22. Cutoff date for analysis was 12/31/2022. HR was defined as the presence of high-risk cytogenetic abnormalities (HRCA) including +1q, del(1p), t(4;14), t(14;16), t(14;20), and/or del(17p), circulating plasma cells (cPC) ≥5%, extramedullary disease (EMD), and/or complex cytogenetics by conventional cytogenetics. Patients who received ≤1 prior cycle of a different MM regimen were included. Responses and progression were evaluated per International Myeloma Working Group Uniform Response Criteria. Discrete patient characteristics were summarized by frequency (percentage) and continuous characteristics were summarized by median (Interquartile Range, IQR). Progression-free survival (PFS) and overall survival (OS) were evaluated by Kaplan-Meier method. Association between time to event outcomes and patient's characteristics were determined by log-rank test. Univariate Cox proportional hazard model was used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs). Results: We identified 179 consecutive NDMM patients with HR features treated with KRd at MSK (N=106) and Winship Cancer Institute (N=73). Baseline patient characteristics are listed in Table 1. The median age was 62 (IQR, 55-68) and 28% of patients were Black. There were 45 (25%), 76 (42%), 47 (26%), and 11 (6%) patients with 0, 1, 2, 3+ HRCA, respectively. A median of 5 (IQR 4-6) cycles were administered. At data cutoff, 70% of patients received upfront autologous stem cell transplant (ASCT). Best overall response rate (ORR) by the end of KRd induction was 94% for 178 response-evaluable patients, including 39% with ≥complete response (CR) and 78% with ≥very good partial response (VGPR). After a median follow-up of 41.9 (95% CI 39-45.6) months, the median PFS (mPFS) was 78.2 months (95% CI 52.5-not reached [NR]), and 2-year estimated PFS was 79% (73%-85%). Median OS (mOS) was not reached, and 2-year OS was 92% (95%CI 89%-97%). For HR subgroups based on the number of HRCA present, mPFS was 78.2 (95% CI 40.1-NR), 65.2 (43.4-NR), 55.9 (44.9-NR), and 17.5 (8.78-NR) months for patients with 0, 1, 2, 3+ HRCA, respectively, with 2-year PFS of 83% (95% CI, 73%-95%), 82% (74%-92%), 78% (67%-91%), and 46% (24%-87%), respectively (P=0.35). Median OS was NR for patients with 0, 1, and 2 HRCA and was 58.2 months (95% CI 38.8-NR) for patients with 3+ HRCA with 2-year OS of 93% (95% CI, 86%-100%), 96% (91%-100%), 89% (81%-99%), and 81% (60%-100%), respectively (P=0.13). In univariable analysis, lack of t(14;16) (HR 0.32, 95%CI 0.11-0.95; P=0.03), White race (HR 0.38, 95%CI 0.17-0.84; P=0.02), presence of ≤2 HRCA (HR 0.31, 95%CI 0.11-0.92; P=0.04) were associated with longer OS in this cohort of HR-NDMM patients treated with KRd induction. Multivariable analysis for clinical variables, including specific HRCA, number of HRCA present, age, gender, race, R-ISS stage, presence of EMD, presence of cPCs, cardiac history, and upfront ASCT did not demonstrate any single variable was a significant predictor of progression or death. Conclusion: For this real-world patient population, KRd induction was associated with high response rates and promising outcomes with best ORR of 94% and mPFS of 6.5 years for patients with high-risk newly diagnosed multiple myeloma consistent with FORTE trial data. PFS did not significantly differ among HR patients with 0, 1, 2, 3+ HRCA although mPFS for patients with 3+ HRCA was only 17.5 months. Data with maintenance therapy and longer follow-up outcomes will be presented at the meeting.

Ultra High-Risk Multiple Myeloma Patients with Multi-Hit Tumours and SKY92 High Risk Signature Are at Increased Risk of Early Relapse Even When Treated with Extended Intensified Induction and Consolidation - Results from the Optimum/Muknine Trial

Background: We recently reported improved outcomes for patients with ultra-high risk (UHiR) newly diagnosed multiple myeloma (NDMM) by double hit/≥2 high-risk cytogenetic abnormalities (HRCA) and/or SKY92 risk signature or primary plasma cell leukemia (pPCL) in the OPTIMUM/MUKnine (NCT03188172; Kaiser et al, JCO 2023) trial. However, some participants still relapsed within the first 18 months of treatment despite stratified intensive therapy with Dara-CVRd, V-ASCT and extended Dara-VR(d) consolidation. In this analysis we characterise factors associated with early progression. Methods: In OPTIMUM, patients with UHiR NDMM (≥2 HRCA: t(4;14), t(14;16), t(14;20), gain(1q), del(1p), del(17p) or SKY92 high risk signature) or with pPCL received up to 6 cycles of Dara-CVRd induction, V-ASCT, 6 cycles Dara-VRd (Cons1) and 12 cycles Dara-VR (Cons2), before moving to monthly Dara-R maintenance until progression. OPTIMUM recruited 107 UHiR patients, including 9 pPCL. In this exploratory analysis, baseline clinical, laboratory and tumour molecular characteristics were compared between patients who experienced an Early Relapse, defined by MM relapse or MM-related death within 18 months from registration and those who did not, using descriptive statistics and hypothesis testing using two-sample t-tests or chi squared tests. Baseline characteristics were also compared by minimal residual disease (MRD; 10 -5 sensitivity by flow cytometry) status at the end of induction to elucidate whether baseline factors associated with early MRD negativity were overlapping with those associated with Early Relapse. Median follow-up was 51.5 months, and all patients had been on study for over 44 months. Results: Twenty-three (21%) of 107 UHiR patients experienced Early Relapse, versus 84 (79%) who did not. Patient age and gender were not different between groups. Platelet levels as a continuous variable were lower in the Early Relapse group vs those without (mean 179/nL, standard deviation (SD) 92/nL vs. mean 223/nL, SD 77/nL; P=0.0247), whereas haemoglobin, serum creatinine, calcium, presence of soft tissue plasmacytomas (PCM), bone lytic lesions or plasma cell bone marrow infiltration on diagnostic trephine were similar. ISS stage distribution differed between groups (P=0.0203): most Early Relapse participants were ISS stage 2 (13/23 (56.5%) vs 30/84 (35.7%) without Early Relapse), whereas ISS stage 3 was nominally similar (34.8% vs 31.0%). Most notably, only one of the 29 ISS stage 1 patients in OPTIMUM experienced Early Relapse. 57 of 107 (53.3%) patients entered OPTIMUM with ≥2 HRCA at diagnosis, and, of these, seven carried 3 HRCA. Five of seven participants (71.4%) with 3 HRCA experienced Early Relapse, opposed to only seven out of 50 (14%) with only 2 HRCA. 82 of 107 (76.6%) were SKY92 high risk at baseline. Only two of the 24 participants (8.3%) with SKY92 standard risk experienced Early Relapse, as opposed to 20 out of 82 (24.4%) with SKY92 high risk. Of individual HRCAs, only presence of del(17p) was associated with early relapse (P=0.002): 8 of 16 (50%) participants with del(17p) tumours experienced Early Relapse. However, seven of these 8 Early Relapse del(17p) tumours (88%) were also positive for SKY92 high risk signature. In contrast, the majority (62%) of del(17p) that did not relapse early were SKY92 standard risk. Of the 107 UHiR patients, 6 did not reach end of induction and 14 had no MRD result. Of 87 participants with interpretable MRD result at end of induction (EOI), 51% tested MRD-negative (44/87). Of clinical factors, only presence of PCM was associated with insufficient response (P=0.017, 5/5 MRD-positive), whereas ISS stage was not associated with MRD at EOI. Only one of four participants (25%) with 3 HRCA had MRD-negative status at EOI vs 66% of those with 2 HRCA. Also, the majority of patients (62%) identified by SKY92 high risk only were still MRD-positive. Conclusions: Our results suggest that presence of 3 or more HRCA, SKY92 high risk signature or del(17p) combined with SKY92 high risk are all associated with increased risk of Early Relapse despite intensified OPTIMUM treatment, and could help identify patients early who are candidates for novel, innovative first-line therapeutic approaches. Results also suggest utility of integrated molecular diagnostics, including gene expression risk profiling, to support clinical decision making in the era of advanced front-line combination therapies.

Final Analysis of a Phase 2 Trial of Daratumumab, Carfilzomib, Lenalidomide, and Dexamethasone in Newly Diagnosed Multiple Myeloma (NDMM) without Autologous Stem Cell Transplantation (ASCT)

Introduction: A previous trial showed that Dara-KRd for 8 cycles without ASCT led to a minimal residual disease (MRD) negativity rate of 71% at 10 -5 in NDMM (Landgren et al. JAMA Oncology 2021). MRD-adapted Dara-KRd with ASCT led to an MRD(-) rate of 71% at 10 -6 with a 3-year progression-free survival (PFS) of 88%, 79%, and 50% in pts with 0, 1 or 2+ high-risk cytogenetic abnormalities (HRCA), respectively (Costa et al. EHA 2022). In this phase 2 study, we evaluated the safety and efficacy of 24 cycles of Dara-KRd without ASCT in pts with NDMM. Methods: Pts with NDMM with up to 1 cycle of prior therapy were enrolled regardless of ASCT eligibility. Pts received Dara-KRd for planned 24 cycles: daratumumab 16 mg/kg IV weekly for cycles (C) 1 &amp; 2, q2weeks for C3-8, then q4weeks for C9-24; carfilzomib 20/36 mg/m 2 on days 1, 2, 8, 9, 15, 16 for C1-8, then 36 mg/m 2 on days 1, 2, 15, 16 for C9-24; lenalidomide 25 mg PO days 1-21 of a 28 day cycle for 24 cycles; dexamethasone 40 mg PO weekly (20 mg if age &amp;gt; 75) for C1-9, and 20 mg PO weekly for C9-24. Pts had the option to harvest stem cells (SC) to permit ASCT in the future. MRD testing was performed by NGS (clonoSEQ, Adaptive Biotechnologies) with sensitivity &amp;lt;10 -6 at the end of cycles 8 (C8), C12, and C24. Mass spectrometry (MS) of peripheral blood samples were also performed using MALDI and liquid-chromatography (LCMS) (The Binding Site Group). The primary endpoint was the rate of stringent CR and/or MRD(-) &amp;lt;10 -5 at the end of C8; the hypothesis was that &amp;gt;50% would meet the primary endpoint with Dara-KRd compared to historical 30% with KRd (85% power, one-sided alpha=0.10). Results: 42 pts enrolled from March 2019-January 2022. Median age was 58 years (range 39-79). 13 (31%) were Black and 5 (12%) were Hispanic. HRCA (t(4;14), t(14;16), t(14;20), +1q, del17p) were present in 24/42 (57%); 10 (24%) had 2+ HRCA. 34 pts (81%) underwent SC collection, all with plerixafor (median yield 8.91x10 6 CD34+/kg). 40 pts (95%) were evaluable for the primary endpoint at C8. Two pts withdrew before C8 for reasons unrelated to treatment. There were 32 (80%) MRD-evaluable pts at C8. The sCR and/or MRD(-) rate (&amp;lt;10 -5) was 30/40 (75%, 95% CI 61%-89%). The C8 10 -5 MRD(-) rate was 20/32 (63%) and at 10 -6 it was 12/32 (38%). Responses deepened over time; 1/12 (8%) and 6/20 (30%) pts converted from MRD(+) at C8 to MRD(-) at later timepoints at 10 -5 and 10 -6 thresholds, respectively, for a best MRD(-) rate of 21/32 (66%) at 10 -5 and 18/32 (56%) at 10 -6 . Sustained 10 -5 MRD(-) &amp;gt;12 months was achieved in 11 (26%) pts; 6 pts were &amp;lt;1 year from first MRD(-) result. Overall response rate at C8 was 38/40 (95%) with 27 (68%) sCR, 38 (95%) VGPR+, and 2 PD. Of the 39 pts with trackable mass spectra in the peripheral blood, the MALDI(-) rate was 22/39 (56%) after C8 and 24/39 (62%) as best response. The LCMS(-) rate was 7/39 (18%) after C8 and 12/39 (31%) as best response. Median follow-up was 27 months. 21 pts (50%) completed all 24 cycles, and 11 (26%) remain on protocol. 7 pts (17%) had disease progression (6 on protocol), including 4 pts who reached the primary endpoint at C8. 4 pts (10%) discontinued protocol therapy early (additional 2 pts due to nonadherence). 1 pt received ASCT after discontinuing while in response. 2 deaths occurred, both early in treatment and due to primary refractory disease. The 3-year PFS was 85%: 100% for standard-risk disease, 92% for 1 HRCA, and 60% for 2+ HRCA. Of the 7 pts with progression, 6 had at least one of: extramedullary disease (4), 2+ HRCA (4), or circulating plasma cells (1). Neither NGS nor mass spectrometry status at C8 were associated with PFS differences using the landmark method. The 3-year OS was 95%. All-grade/grade 3+ (G3) neutropenia occurred in 26%/21%, anemia in 59%/2%, and thrombocytopenia in 64%/26%. Notable nonhematologic adverse events were hyperglycemia (all 76%/ G3+ 7%), diarrhea (71%/5%), hypertension (57%/17%), and neuropathy (40%/0%). COVID infections occurred in 38% (2% G3) and upper respiratory infections in 45% (0% G3+). There was one case of thrombotic microangiopathy leading to discontinuation of carfilzomib. G3 atrial fibrillation and heart failure each occurred in 1 pt. Conclusions: Extended frontline Dara-KRd for NDMM without ASCT induced high rates of sCR and/or MRD(-) within 8 cycles, meeting the primary endpoint. The rate and depth of MRD(-) improved beyond C8. This ASCT-free approach led to lower PFS for pts with 2+ HRCA, as also seen with ASCT, but excellent PFS in those with standard-risk disease and 1 HRCA.

Efficacy of Bispecific Antibodies Vs CAR-T in the Treatment of Extramedullary Disease and High-Risk Cytogenetics in Relapsed Multiple Myeloma: A Systematic Review and Meta-Analysis

Background: Bispecific antibodies (BsAb) and Chimeric antigen receptor T-cell therapy (CAR-T) have emerged as a promising treatment option for patients with relapsed, refractory multiple myeloma (RRMM) for greater than four previous lines of therapy. The efficacy of these novel drugs in extramedullary disease (EMD) and high-risk cytogenetic abnormalities (HRCA) is relatively less reported. The purpose of this systematic review and meta-analysis is to compare the efficacy of BsAbs vs CAR-T in the treatment of EMD and HRCAs in RRMM. Methods: A systematic literature search was conducted to identify clinical trials that investigated BsAbs and CAR-T therapies in treating RRMM patients using the PubMed, Cochrane, ASH 2022 and ASCO 2023 abstracts using search terms (bispecific antibodies) AND (multiple myeloma), (CAR T cell therapy) AND (multiple myeloma). For BsAbs, our search on PubMed yielded 263 studies. 7 were clinical trials and 5 of these were included. 6 ASH abstracts and one ASCO abstract were also included resulting in a total of 12 studies considered for this meta-analysis. For CAR-T, our search on PubMed and COCHRANE yielded 84 and 20 studies respectively. After screening, we have included 21 studies and 6 ASCO abstracts in final analysis. RStudio Desktop Version 2023.03.0+ 386 was used for statistical analysis. Cochrane-Q test and I² statistic were used to assess the statistical heterogenicity. Fixed effect model was used for low statistical heterogeneity (P &amp;gt; 0.05 in Cochrane-Q test and I² &amp;lt; 50%), while a random effect model was used for high statistical heterogeneity (P &amp;lt; 0.05 in Cochrane-Q test and I² &amp;gt; 50%). Categorical outcomes were summarized by pooled proportion with 95% CI. Subgroup analysis was performed wherever required. P &amp;lt;0.05 was considered statistically significant. Results Bispecific antibodies Overall response rates (ORR) were reported in a study population of 823 patients across 12 studies. The ORR was reported in 4 studies (n=106) for EMD and 4 studies (n=100) for HRCA respectively. The pooled ORR was 0.67 [95% CI; 0.59; 0.76) for the whole group. The pooled ORR was 0.48 (95% CI of 0.31 to 0.65) for EMD and 0.60 (95% CI of 0.51 to 0.70) for HRCA respectively. Subgroup analysis showed that there was a statistically significant difference in overall response rate according to different targets. However, there was no statistically significant difference in the ORR between the drugs with respect to EMD and HRCA. Combination therapy of Teclistamab and Talquetamab has highest ORR and RR in EMD disease compared to other BsABs in a study by Cohen et al. Funnel plot is symmetrical and showed no probability of publication bias for overall response rate for bispecific antibodies with a p-value of 0.676. CAR T cell therapy ORR with CAR-T cell therapy was reported across 27 studies with pooled sample size of 1469. The ORR was reported in 14 studies (n=172) for EMD and 11 studies (n=268) for HRCAs, respectively. The pooled ORR was 0.86 (95% CI of 0.82 to 0.90). The pooled proportion of RR among MM patients with EMD and HRCAs was 0.77 (95% CI of 0.68 to 0.87) and 0.77 (95% CI of 0.69 to 0.86), respectively. Funnel plot asymmetry showed possible publication bias for overall response rate for CAR T cell therapy with p-value of 0.021. Bispecific antibodies vs CAR-T. ORR in the whole cohort (P &amp;lt;0.001), EMD cohort (P &amp;lt;0.001), and HRCA cohort (P &amp;lt;0.046) were found to be significantly higher in CAR-T cell therapy as compared to bispecific antibodies. Conclusion: BsABs and CAR-T cell therapy are effective treatment options for relapsed MM patients.ORR in the whole cohort, EMD cohort, and HRCA cohort were found to be superior with CAR T cell therapy. However, it is difficult to make direct comparisons of pooled estimates of two different therapies. There was no significant difference in EMD and HRCA between the different types of BsAb therapy. Better reporting of EMD responses is urgently needed in published clinical data to know the true effect size and develop strategies to overcome this.

Risk Stratification Models Overestimate Progression Risk in Contemporary Patients with Smoldering Multiple Myeloma (SMM)

Introduction: SMM is an asymptomatic precursor of multiple myeloma (MM), affecting ~1 in 200 people aged &amp;gt;40 years. Historically, risk of progression from SMM to MM was 10% per year in the first 5 years. However, since then, the definition and characteristics of the SMM patient population have changed substantially. First, IMWG diagnostic criteria for MM in 2014 changed to include biomarker-only myeloma (SLiM), reclassifying asymptomatic patients previously considered SMM. Second, incorporation of advanced imaging (CT, PET/CT, MRI) identified bone disease with greater sensitivity. Hence, we hypothesized that in the contemporary era, the risk of progression from SMM to MM would be markedly lower than historically. Methods: We performed a retrospective cohort study of consecutive patients with SMM at Columbia University Irving Medical Center from 2014-2022 and observed without therapeutic intervention. Our primary objective was to measure cumulative incidence of progression to MM and to characterize progression events. We also calculated predicted 2-year risk of progression by different risk-stratification models (Mayo 20/2/20, PANGEA, IMWG SMM model) in our cohort. Results: 102 consecutive patients with SMM were included. Median year of diagnosis was 2019 (range, 2014-2022). Baseline clinical and demographic characteristics of the cohort are shown in Table 1. The three most common scenarios that led to SMM diagnosis were workup of anemia/cytopenias(s) (n=22; 21.8%), incidental protein gap or elevated immunoglobulin level (n=20; 19.8%), and renal dysfunction (n=16; 15.8%). The racial/ethnic makeup of our study cohort was 38% Hispanic/Latino, 38% Non-Hispanic White, 19% Black/African-American, and 5% Asian. Bone disease was ruled out by advanced imaging (whole body CT, PET/CT, WB-MRI, and/or MRI spine+ pelvis) in 81.2% of patients. The most common abnormality on FISH was hyperdiploidy (39.2%), followed by t(11;14) (22.1%), with ≥1 high-risk cytogenetic abnormality (HRCA) in 35% of patients. Median follow-up was 45 months (95% CI, 34-52). 22/102 patients (21.6%) progressed to symptomatic plasma cell dyscrasia: CRAB myeloma in 18, SLiM myeloma in 1, systemic AL amyloidosis in 3 patients. The cumulative incidence of progression to MM (CRAB/SLiM) at 1, 2, 3, and 4 years from SMM diagnosis was 3.1% (95% CI, 0.99-9.1), 7.7% (95% CI, 3.7-15.3), 13.9% (95% CI, 8.1-23.1), and 17.1% (95% CI, 10.3-27.1) respectively [Figure 1]. Notably, presence of HRCA by FISH had a dose-dependent increase in risk of progression, with the 2-year risk being 75% (95% CI, 24-97%) in patients with ≥2 HRCA vs 13.0% (95% CI, 5.9-26.3) in those with 0-1 HRCA respectively ( p=0.0049). Among 18 patients who progressed to CRAB myeloma, the myeloma-defining event/s (MDEs) were anemia in 11, anemia + bone disease in 4, and bone disease in 3 patients. Among patients with a bone disease MDE, 4/7 had &amp;gt;1 lytic lesions on imaging and 3 had vertebral compression fracture(s). No patient had renal insufficiency or hypercalcemia as MDE. The sole patient with SLiM had a serum free light chain ratio&amp;gt;100 as the only MDE. 13/102 patients (12.75%) died, with 4/13 deaths attributed to myeloma after disease progression. The predicted median 2-year risk of progression to MM with different risk-stratification models were as follows: PANGEA with Bone Marrow (BM): 5.75% (range, 1.2-42); PANGEA without BM: 4.6% (0.7-26.6); Mayo 20/2/20: 9.7% (9.7-47.4); IMWG SMM: 26% (3.8-73). Figure 2 shows Sankey diagram of predicted risk tertiles for patients at SMM diagnosis by different models. Notably, a substantial proportion of high-risk patients by 20/2/20, who are currently considered for therapeutic intervention, were re-assigned to intermediate risk (2-year risk of progression 8.1-20%) by PANGEA-BM. Conclusion: The risk of progression to MM among this cohort of contemporary patients with SMM is &amp;lt;5% per year for the 1 st 4 years, which is substantially lower than the historical rate of 10% per year. Morbid progression such as renal failure or fractures are very infrequent, with anemia being the most common MDE. Prospective studies testing active surveillance strategies are needed in contemporary SMM cohorts to determine the optimal approach to these patients and ensure balancing of potential risks and benefits of treatment.