Citations 128

Idecabtagene Vicleucel (Ide-cel) in Patients (Pts) with Newly Diagnosed Multiple Myeloma (NDMM) with an Inadequate Response to Front-Line Autologous Stem Cell Transplantation (ASCT): KarMMa-2 Cohort 2c Extended Follow-up

Blood | December 6, 2024 | Volume: 144 | Issue: Supplement 1 | Pages: 3388-3388

10.1182/blood-2024-200829

Introduction Induction therapy (Tx) followed by ASCT and lenalidomide (LEN) maintenance is the standard of care in transplant-eligible pts with NDMM. Pts who have suboptimal response after front-line ASCT, however, have an increased risk of progression or death. Ide-cel demonstrated significantly improved median progression-free survival (PFS) and overall response rate (ORR) vs standard regimens in KarMMa-3 in pts with early-line triple-class-exposed relapsed and refractory multiple myeloma (MM). KarMMa-2 (NCT03601078) is a multicohort, phase 2, multicenter trial evaluating the efficacy and safety of ide-cel in several MM disease settings; cohort 2c includes pts with NDMM who achieved < very good partial response (VGPR) after front-line ASCT. An extended follow-up analysis (median follow-up of 39.4 months) of cohort 2c was presented at ASH 2023 (Dhodapkar M, et al. ASH 2023; P2101). Here, we report results with 55.4 months of median follow-up and additional data on pts who received LEN maintenance at the investigator's discretion. Methods Adult pts with NDMM who received ≥ 3 cycles of induction Tx (proteasome inhibitor, immunomodulatory agent, dexamethasone), and had < VGPR 70-110 days after ASCT (single/tandem) were eligible. Pts received a single ide-cel infusion (150-450 × 106 chimeric antigen receptor-positive T cells) and could receive maintenance Tx post-infusion at investigator discretion. The primary endpoint was complete response rate (CRR); secondary endpoints included ORR, duration of response (DOR), PFS, overall survival (OS), safety, cellular kinetics, and patient-reported outcomes on health-related quality of life (HRQoL). Minimal residual disease (MRD) negativity (sensitivity, 10-5), an exploratory endpoint, is also reported. Results At data cutoff (June 28, 2024), with a median follow-up of 55.4 (range, 51.4-59.5) months, all 31 pts treated with ide-cel were alive; 28 (90.3%) remained in follow-up and 3 (9.7%) discontinued due to disease progression or withdrawal by pt. Eight pts received LEN maintenance after ide-cel at the investigator's discretion. Among all 31 ide-cel-treated pts, CRR and ORR were 80.6% and 87.1%, respectively. Among the 8 pts who received LEN maintenance, CRR and ORR were 75.0% and 100.0%, respectively. Median DOR, PFS, and OS were not reached; 36-month event-free rates were 81.5%, 76.8%, and 100.0%, respectively. Of the 8 pts who received LEN maintenance after ide-cel infusion, none experienced disease progression. At 36 months, MRD negativity was confirmed in 12/18 (66.7%) evaluable pts; all 12 achieved ≥ CR. Since last data cutoff, 1 pt with MRD-negative MM changed to MRD-positive at 36 months, and 1 pt who had previously achieved MRD negativity was indeterminate at 36 months. Among the 6 evaluable pts who received LEN maintenance, 3/6 (50.0%) achieved MRD negativity at 36 months. There were no new safety signals nor reports of parkinsonism or Guillain-Barré syndrome since the previous data cutoff. In the 8 pts who received LEN maintenance, 6 (75.0%) experienced grade 3/4 AE, most commonly neutropenia, and 1 (12.5%) experienced grade 3/4 infection on or after LEN maintenance. All 8 pts were still receiving LEN at data cutoff. Robust CAR+ T cell expansion was observed in 31 pts, with higher expansion in pts with ≥ CR vs < CR. Following ide-cel treatment, HRQoL improved and disease symptoms were stable over time (assessed by European Organization for Research and Treatment of Cancer [EORTC] Quality of Life Core Questionnaire and EORTC Quality of Life Multiple Myeloma Module 20 Questionnaire). More than 75% of pts had improved or stable global health status/QoL by month 3. Conclusions With extended follow-up, ide-cel continued to demonstrate deep, durable responses in pts with < VGPR to front-line ASCT. No new safety signals were observed and no deaths were reported. Data in a small group of pts in cohort 2c showed that ide-cel followed by LEN maintenance extended disease control. Pts who received LEN maintenance did not experience disease progression regardless of MRD status. Stable or improved HRQoL was observed after ide-cel treatment. Overall, ide-cel continued to show a favorable clinical benefit-risk profile in NDMM after ASCT. The phase 3 KarMMa-9 study (NCT06045806), currently recruiting, will compare ide-cel followed by LEN maintenance vs LEN maintenance alone in pts with NDMM after suboptimal response to ASCT.
Development of the ASH Research Collaborative Multiple Myeloma Program: A Multicenter, Real-World Evidence Generation Network

Blood | December 6, 2024 | Volume: 144 | Issue: Supplement 1 | Pages: 3792.5-3792.5

10.1182/blood-2024-210957

Background: Contemporary questions about treatment and outcomes of patients (pts) living with multiple myeloma (MM) demand efficient and timely evidence generation methods, where real-world/ everyday practice data can play an important role. Relevant potential applications include understanding and addressing disparities in treatment access, mitigating toxicities of novel therapies while maintaining quality of life, appropriately sequencing treatments within long-term management strategies, and disseminating and appropriately using surrogate endpoints in practice, such as minimal residual disease. However, existing real-world data (RWD) repositories are limited by an inability to implement interventions in response to issues identified through retrospective data analysis, which is pivotal for the use of newer therapies. The ASH Research Collaborative (ASH RC) MM Data Hub Program was developed to address these gaps. Methods: We developed a multicenter network of US-based tertiary academic medical centers, engaging site clinicians, patients, biostatisticians, informaticians, and data scientists. Initial activities included constructing a shared real-world MM data model comprised of consensus core data elements. Pt data from each site, dating back to at least 2019, is currently being entered through electronic case report forms, batch uploaded utilizing existing institutional data repositories, and soon direct electronic health record import in standard data acquisition formats. Data are aggregated in the Data Hub and shared in a confidential Site Portal with each site. The Portal allows sites to track their own pts, analyze outcomes, and identify ways to improve the quality of care provided to individuals living with MM. We also developed an innovative evidence generation learning community of site clinicians who meet monthly and collaborate on the “COVID-19 OutcomeS in Myeloma and the Impact of VaCcines (COSMIC)” study, a prospective, decentralized observational study that rapidly accrued pts and collects relevant practice information. The group also shares best practices in study conduct to accelerate study enrollment and execution. Results: The MM Data Hub Program now contains twelve centers: Memorial Sloan Kettering Cancer Center, Mayo Clinic, Icahn School of Medicine at Mount Sinai, University of California San Francisco, University of California Davis, Medical College of Wisconsin, Barbara Ann Karmanos Cancer Institute, University of North Carolina Medical Center at Chapel Hill, Emory University Hospital, Washington University School of Medicine in St. Louis, Dana-Farber Cancer Institute, and Atrium Health. From this Network, six centers have contributed data from 8,824 pts (2,825 with sufficiently complete data are included in this analysis). The median age at time of MM diagnosis is 63, and of the 627 deceased pts, the median age at death is 70.6 years, with median time to death from first MM diagnosis of 6 years. The proportions of pts by decade of diagnoses are 34.9% from 2020-2024; 57.6% from 2010-2019; 7.3% from 2000-2009; and 0.9% prior to 2000. 83.1% of pts had a diagnosis of plasma cell myeloma (non-light chain), and 14.4% of pts had a diagnosis of light chain myeloma. 42.3% of pts are female, and the self-reported patient races are: 85.0% white; 9.2% black or African; and 4.3% all other races (race was not documented in 1.5% of pts). 2.8% of pts are of Hispanic ethnicity. Participant data files are currently undergoing completion and cleaning procedures; the analysis will include updated results at the meeting, and a Network-wide analytic data set will be available for initial retrospective data analyses in early 2025. The COSMIC study opened for enrollment on January 22, 2024, and completed enrollment of 200 pts on May 17, 2024. Conclusions: The ASH RC Data Hub MM Program launched in 2023 and is comprised of 12 sites that collectively have contributed participant files for 8,824 pts thus far. Utilizing the structure of the Network, we successfully implemented and established the feasibility of collecting data directly from pts electronically to monitor SARS-CoV-2 vaccines and COVID-19 related outcomes. The Program serves as a successful proof-of-concept model, providing an enduring RWD resource and a prospective evidence generation platform for the myeloma community.
Feasibility and Implementation of the ASH Research Collaborative's COVID-19 Outcomes in Myeloma and the Impact of Vaccines (COSMIC): A Decentralized, Real-World Evidence Study for Patients with Multiple Myeloma to Monitor Outcomes Related to COVID-19 Vacci

Blood | December 6, 2024 | Volume: 144 | Issue: Supplement 1 | Pages: 2393-2393

10.1182/blood-2024-203892

Background: The COVID-19 pandemic had an outsized impact on individuals with immune compromise, such as multiple myeloma, leading to increased rates of severe COVID, hospitalization, and death in these groups. The pandemic also demonstrated the need for rapid and efficient evidence generation to address rapidly changing medical needs and accelerated the use of innovative trial designs to accomplish this goal. Methods: We designed and established a prospective, decentralized study within a site-based provider network, COVID-19 OutcomeS in Myeloma and the Impact of VaCcines (COSMIC), for patients with multiple myeloma at ASH Research Collaborative sites to monitor outcomes related to COVID-19 infection and vaccination. The direct-to-patient approach was accomplished using a study application accessed with a QR code provided to patients during usual clinical care. All study activities occurred within the patient portal at Baseline, Day 30, and Day 180, minimizing burden on site personnel and staff. Study activities included eligibility confirmation, consenting, electronic health record (EHR) data permissions, and patient-reported outcome (PRO) surveys. PRO data (EORTC QLQ-C30, EORTC QLQ MY-20) were made available to clinicians through the portal to visualize results from their patients. Patients shared if they received a COVID-19 vaccination or booster and if they had a COVID-19 infection. Patients with a history of COVID-19 infection included method of confirmation and if hospitalization was required. Patients were provided compensation for participation. Automated text and email messages were sent at three separate intervals: 24 hours, Day 8, and Day 15 for participants who initiated but did not complete study activities. A personal email reminder per participant was sent for those whose second study visit window was approaching. ASH Research Collaborative clinicians met regularly to share best practices related to enrollment and study conduct, thereby creating an innovative evidence generation learning community. We studied the feasibility of data collection in a decentralized format by focusing on the number of participants who interacted with the system, those who consented, and those who completed baseline PRO assessments. Results: The COSMIC study rapidly accrued and consented 200 patients from eight participating ASH Research Collaborative sites over four months (1/22/2024 through 5/17/2024): 69% self-reported as non-Hispanic White (NHW). Of enrolled participants, 57.5% opted to permission sharing of their EHR data, which included disease and treatment-related clinical data, laboratory results, pathology reports, and imaging reports. A total of 196 patients (98%) provided demographic and COVID-related disease and vaccine data at baseline; nearly all of these patients (n=195) provided baseline PRO data, and 150 patients provided further information at Day 30 at the time of this analysis. Those who did not provide Day 30 data were not significantly different from those who did in terms of age (median: 68 [no Day 30 data] vs. 67 [Day 30 data] years; p=0.44), sex (41% [no Day 30 data] vs. 47% [Day 30 data] Female; p=0.47), or race (65% [no Day 30 data] vs. 71% [Day 30 data] NHW; p=0.60). A higher proportion of Hispanic patients were retained at Day 30 (13/15=87%) vs. 78% of non-Hispanic patients or those who declined reporting ethnicity (2/7=29%; p=0.007). COVID-19 vaccination data were submitted by 196 patients, 186 of whom had ever received a COVID-19 vaccination. Data on number, type, brand, and dates for these vaccinations were provided. Conclusions: The COSMIC study conducted by the ASH Research Collaborative was able to rapidly accrue a diverse cohort of patients using a decentralized workflow within a site-based provider network, with high consent and compliance rates. This platform, and the innovative evidence generation learning community of ASH Research Collaborative investigators and patients, sets a precedent to address a variety of real-world questions related to disease management, infections, vaccinations, and PROs in this population of patients with multiple myeloma.
Initial Results from the ASH Research Collaborative's COVID-19 Outcomes in Myeloma and the Impact of Vaccines (COSMIC): A Decentralized, Real-World Evidence Study for Patients with Multiple Myeloma to Monitor Outcomes Related to COVID-19 Vaccines and Infec

Blood | December 6, 2024 | Volume: 144 | Issue: Supplement 1 | Pages: 1972-1972

10.1182/blood-2024-210377

Background: Data from the ASH Research Collaborative COVID-19 Registry for Hematology demonstrated that patients with multiple myeloma and other immune compromise had elevated risk for severe complications from COVID-19 infection. To address current evidence gaps and to demonstrate proof of concept for a pandemic preparedness and response network, the ASH Research Collaborative Multiple Myeloma Program developed a prospective, decentralized study within a site-based provider network to investigate COVID-19 infections, vaccinations, and quality of life in patients with multiple myeloma. Methods: We designed and established the COVID-19 OutcomeS in Myeloma and the Impact of VacCines (COSMIC) to study COVID-19 in patients with multiple myeloma at ASH Research Collaborative network sites. A study application was accessed with a QR code and shared with patients during usual clinical care. Patients provided consent, optionally gave permission for electronic health record data collection, and completed patient-reported outcomes (EORTC QLQ-C30 and MY20) at baseline, Day 30, and Day 180 through the study portal. Clinicians at participating sites facilitated study enrollment and shared best practices monthly to accelerate study execution. Study objectives related to feasibility of data collection in a decentralized format are reported in a separate abstract. Here, we report interim results related to SARS-CoV-2 vaccination history, COVID-19 infection, and how these relate to patient reported outcomes and clinical outcomes in enrolled participants. Results: The COSMIC study rapidly accrued and consented 200 patients from eight participating ASH Research Collaborative sites over four months (1/22/2024 through 5/17/2024). Consented participants' ages ranged from 29 to 93 years, with median of 67 years; 46% were female, 69% were non-Hispanic White (NHW), 17% were non-Hispanic Black (NHB), and 8% were Hispanic/Latino. Of the 196 patients who reported COVID-19 data, 111 (57%) reported at baseline that they had a history of COVID-19 infection, with 12 having required hospitalization for this (12/111=11%). Overall, 95% (186/196) reported a history of COVID-19 vaccination, where the median number of vaccinations was 4 (range: 1 to 6); 44 patients (23%) expressed willingness to discuss getting a yearly booster vaccine with their provider. At 1-month follow-up, there were 3 additional patients who reported a COVID-19 infection and 18 patients who received an additional COVID-19 vaccination. The baseline EORTC QLQ-C30 median Global Health Status/QOL score was 66.7 (mean=64.4, range: 8.3 - 100, n=196). This overall global QOL score was not significantly different between those who did vs. did not have a history of COVID-19 infection (mean [SD]: 63.7 [19.3] vs. 65.8 [17.6]; p=0.57). In analyses adjusted for age, biological sex, and race/ethnicity group, history of COVID-19 infection was not associated with HRQOL (odds ratio=0.93, 95% CI: 0.78 - 1.10; p=0.38). Data collection is ongoing and final study results will be reported at a later date. Conclusion: COSMIC is a prospective, decentralized study within a site-based provider network conducted by the ASH Research Collaborative Multiple Myeloma Program that demonstrates the feasibility of using an innovative evidence generation strategy to drive rapid accrual of patients to address a rapidly evolving area of need. The COSMIC study also provides proof of concept that a real-world evidence generation network can play an important role in national pandemic preparedness and response. The COSMIC experience reinforces the ability to accrue diverse patient populations representing the demographic of myeloma patients in the US.
Correlative biomarker analyses for optimal therapeutic dose determination of ABBV-383, a B-cell maturation antigen (BCMA) x CD3 bispecific antibody, in patients with relapsed/refractory multiple myeloma (RRMM).

Journal of Clinical Oncology | June 10, 2024 | Volume: 42 | Issue: 16_suppl | Pages: 7532-7532

10.1200/jco.2024.42.16_suppl.7532

7532 Background: ABBV-383 is a BCMA x CD3 bispecific antibody with 2 high-affinity BCMA-binding domains and a low-affinity CD3 engaging arm that has been shown to decrease the negative impact of soluble BCMA (sBCMA) and drive sustained T-cell activation with reduced cytokine release in preclinical models of MM. Here, we describe correlative biomarker results of baseline and longitudinal sBCMA levels and immune profiles in the ongoing first-in-human trial that supports 60 mg Q4W as the optimal therapeutic dose of ABBV-383 monotherapy. Methods: Peripheral blood and serum samples from patients with RRMM enrolled in the phase 1 open-label, dose-expansion study (NCT03933735) who received ABBV-383 at 20, 40, or 60 mg Q3W or 60 mg Q4W were collected at baseline (post-dexamethasone, pre–ABBV-383), on treatment, and at disease progression. Samples were analyzed by flow cytometry for immune cell populations, Luminex for cytokines, and electrochemiluminescence ligand binding for sBCMA. Results: Median sBCMA levels at baseline were highly variable among patients, but did not associate with clinical response (≥ partial response [PR]) to ABBV-383 at the selected optimal dose level of 60 mg Q4W (<PR: 244.7 ng/mL; ≥PR: 52.2 ng/mL; P=0.13). Reduction in sBCMA levels over time associated with clinical response (Cmin at cycle 5: <PR, 244.7 ng/mL; ≥PR, 4.7 ng/mL; P=0.04). ABBV-383 treatment led to a rapid and transient increase of proinflammatory cytokines, including IL-6, IL-8, IL-10, TNF-α (Cmax within cycle 1: 29, 349.5, 1375, 456.5 pg/mL, respectively), and promoted T-cell redistribution (89% reduction of CD8+ T cells from periphery), activation (1.9-fold increase in CD69+CD8+ T cells), and proliferation (2-fold increase in Ki67+CD8+ T cells) within cycle 1 in 60-mg Q4W-treated patients. The frequency of baseline CD8+ T-cell exhaustion (PD-1/TIM3) did not impact clinical response at the optimal dose level of 60 mg Q4W ABBV-383 (<PR: 3.5%; ≥PR: 3.9%; P=0.9). Peak induction levels of proinflammatory cytokines during cycle 1 correlated with occurrence of cytokine release syndrome (≥G1) as well as clinical response across dose levels. Conclusions: High-avidity BCMA binding coupled to low-affinity T-cell engagement distinguishes the resulting mechanism of action for ABBV-383. Responses to 60 mg Q4W ABBV-383 were independent of baseline sBCMA levels and resulted in rapid and transient proinflammatory cytokine production that promoted robust T-cell redistribution, activation, and proliferation, indicating that the optimal dose of ABBV-383 maximizes its clinical potential as a convenient, safe, and effective therapy for MM. Clinical trial information: NCT03933735 .
Plain language summary of the KarMMa-3 study of ide-cel or standard of care regimens in people with relapsed or refractory multiple myeloma

Future Oncology | April 23, 2024 | Volume: 20 | Issue: 18 | Pages: 1221-1235

10.2217/fon-2023-0954 | PMID 38651976

Updated Safety and Efficacy Results of Abbv-383, a BCMA x CD3 Bispecific T-Cell Redirecting Antibody, in a First-in-Human Phase 1 Study in Patients with Relapsed/Refractory Multiple Myeloma

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 3378-3378

10.1182/blood-2023-182388

Background ABBV-383 is an off-the-shelf, fully human B-cell maturation antigen (BMCA) X CD3 bispecific antibody with bivalent BCMA domain and low CD3 affinity that targets both BCMA-expressing multiple myeloma (MM) cells and CD3-expressing T cells. ABBV-383 has shown promising activity in an ongoing phase 1 study in patients (pts) with relapsed/refractory (RR) MM ( Voorhees et al. ASH 2022; Weisel et al. EHA 2023). Here, we report the safety and efficacy results from the ABBV-383 IV Q3W at 20 mg, 40 mg and 60 mg dose levels. Methods The phase 1 dose escalation (ESC) and expansion (EXP) study (NCT03933735) of ABBV-383 enrolled pts with RRMM with ≥3 prior lines of therapy (LOT), including a PI, IMiD, and an anti-CD38 mAb with no prior BCMA exposure. After exploring 14 dose levels in dose ESC, 3 dose levels were further explored in dose EXP including ABBV-383 Q3W IV 20 mg, 40 mg, and 60 mg, until disease progression/unacceptable toxicity. The primary objectives were to determine safety/tolerability, PK/PD, and RP2D. The secondary objective was to evaluate clinical activity. Responses were investigator assessed per IMWG 2016 criteria and adverse events (AEs) by CTCAE v5.0. Results As of 17May2023, 220 pts were treated with ABBV-383, 73 pts in the dose ESC and 147 in the dose EXP with 32 pts at 20 mg, 55 pts at 40 mg, and 61 pts at 60 mg Q3W. Median duration of follow up was 7.1 (0.8-36.9), 12.2 (1.3-34.4) and 24.2 (0.6-33.4) months (mo) in the 20 mg, 40 mg and 60 mg dose levels with 25%, 36% and 21% pts continuing treatment (tx), respectively. Median age for all pts was 68 yrs (range, 35-92 yrs), Median prior LOT was 5 (range, 3-23), and 80% were triple-class refractory. Baseline characteristics are summarized in Table 1 by dose level. Treatment-emergent (TE) AEs were reported in 97% (78% ≥G3) of pts at 20 mg, 100% (84% ≥G3) of pts at 40 mg, and 100% (82% ≥G3) of pts at 60 mg. CRS, the most common TEAE, occurred in 50% (34% G1/13% G2/3% G3) of pts at 20 mg, 71%(45% G1/25% G2/0% ≥G3) of pts at 40 mg, and 70%(51% G1/18% G2/2% G3) of pts at 60mg. At the 3 dose levels, CRS occurring after the first dose had median time to onset of 1 day (range, 1-2) and median duration was 2 days (range, 1-10). ICANS occurred in 3% (3% G1/0% ≥G2) of pts at 20 mg, 5% (2 % G1/4% G2/0% ≥G3) of pts at 40 mg, and 5% (3% G2/2% G3) of pts at 60 mg. No G4/5 CRS or ICANS occurred. Infections occurred in 56% (25% ≥G3) of pts at 20 mg, 71% (26% ≥G3) of pts at 40 mg, and 57% (34% ≥G3) of pts at 60 mg; most frequently (≥10%) reported were upper respiratory tract infections (15%, G3/4 1%), pneumonia (14%, G3/4 12%), urinary tract infections (12%, G3/4 3%), and COVID-19 (11%, G3/4 1%). At 20 mg, 40 mg, and 60 mg, the incidence of neutropenia was 41% (25% ≥G3), 42% (31% ≥G3), and 43% (34% ≥G3); anemia 50% (25% ≥G3), 55% (31% ≥G3), and 38% (13% ≥G3); thrombocytopenia 44% (28% ≥G3), 36% (16% ≥G3) and 26% (13% ≥G3), respectively. The tx discontinuation due to AEs was 6%, 11%, 10% in 20 mg, 40 mg and 60 mg, respectively, with no single PT reported in &gt;2 pts. Clinical responses are shown in Figure 1. The median time to ≥VGPR was 0.7mo (0.7-5.8) at 20 mg, 1.0mo (0.7-10.4) at 40 mg, and 1.4 mo (0.7-7.8) at 60 mg. The median DOR was 9.7 mo (3.5-not reached (NR)) at 20 mg, and NR at 40 mg and 60 mg. The Kaplan-Meier (KM) estimates for DOR at 12 mo was 42% at 20 mg, 70% at 40 mg, 66% at 60 mg. The mPFS was 3.8 mo (2.4-7.9) at 20mg, 13.7mo (5.0-NR) at 40 mg, and 11.2 mo (4.8-NR) at 60 mg. The KM estimates for PFS at 12 mo was 19% at 20 mg, 51% at 40 mg, 49% at 60 mg. The median OS was 21.6 mo (7.9-NR) at 20 mg, and NR at 40 mg and 60 mg. ABBV-383 at 20 mg, 40 mg, and 60 mg led to rapid and transient production of key proinflammatory cytokines (IL-6, IL8, IFN-γ, and TNF-α), and reduction of soluble BCMA levels over time that were associated with disease response. ABBV-383 also promoted T-cell activation and proliferation with upregulation of CD69 and KI67 markers on peripheral CD4 and CD8 T cells in evaluable pts. Conclusions ABBV-383 showed a manageable safety profile at dosages of 20 mg, 40 mg, and 60 mg IV Q3W, with low incidence of TEAEs leading to discontinuation. Also, extended Q3W dosing interval with no step-up dosing schedule of ABBV-383 may provide enhanced convenience. However, 20 mg yielded numerically lower responses when compared to 40 mg and 60 mg. At 40 mg and 60 mg, ABBV-383 monotherapy yielded deep and durable responses with mPFS of 13.7 mo and 11.2 mo, and 12-month DOR of 70% and 66% (mDOR NR in pts with ≥CR), respectively. These results in heavily pretreated RRMM pts support further clinical evaluation.
In-Depth Characterization of the High Risk-Associated Tumor Immune Landscape in Multiple Myeloma

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 648-648

10.1182/blood-2023-189940

Introduction Newly-diagnosed multiple myeloma (MM) patients often share tumor genetic abnormalities associated with a high risk of progression and poor survival. We hypothesized that single-cell transcriptomic characterization of the tumor immune microenvironment (TIME) may be combined with tumor-based risk stratification to uncover novel disease biology mechanisms associated with clinical outcomes and improve risk stratification. Methods We performed single-cell RNA sequencing of 361 CD138 negative sorted bone marrow mononuclear cells (BMMCs) samples from 263 MM patients enrolled at time of diagnosis in the Multiple Myeloma Research Foundation CoMMpass study (NCT01454297). Specimens were analyzed at baseline (n=263) across a network of five collaborating academic research centers following assay harmonization. Genetic factors that determine risk were defined as one or more of the following gain- or loss-of-function events derived from baseline genomic sequencing data: del17p14, translocations of the Ig locus with the MAF/A/B or WHSC1/MMSET/NSD2 loci, and gain of chromosome 1q21. Statistical modeling strategies were used to assess single-cell populations or RNA signatures associations with known risk factors or disease progression (FDR&lt;0.05). Results The study generated high-quality single-cell profiles of 731,643 cells from 123 high-risk and 107 standard-risk MM patients based on genetics. Based on distinct transcriptome profiles, BMMCs formed 106 clusters corresponding to 5 major compartments: NK and T cells, B cells, erythrocytes, myeloid cells, and plasma cells. Our preliminary differential abundance analysis comparing high- vs standard-risk patients at baseline uncovered significant differences in the TIME associated with genetic risk. The high-risk group was identified as enriched in effector CD8+, and CD4+ T cells. In contrast, the high-risk group exhibited depletion of naive CD8+ and interferon-associated CD4+ and CD8+ T as compared to the standard-risk group. Within subclusters in the T and NK cells compartment, a higher cytotoxicity signature was observed in high-risk patients, characterized by the expression of granzymes and perforin. Finally, our preliminary survival and progression analysis associated a higher frequency of IDO1-expressing macrophages in worst progression patients, while better outcomes were associated with CD8+ T and B cells expressing androgen response and IL6/STAT3/EMT programs, respectively. Conclusions Current approaches for risk stratification are based on bulk measurements of tumor's genetic or epigenetics features, which do not capture the diversity and dynamics of the TIME. Through single-cell transcriptomics, we were able to capture, in high granularity, the TIME and correlate specific immune cell populations and phenotypes with relapse risk and poor prognostic outcomes. These results suggest that immune subpopulations may be an essential novel aspect for improving current risk stratification models.
Efficacy and Safety of Idecabtagene Vicleucel (ide-cel) in Patients with Clinical High-Risk Newly Diagnosed Multiple Myeloma (NDMM) with an Inadequate Response to Frontline Autologous Stem Cell Transplantation (ASCT): KarMMa-2 Cohort 2c Extended Follow-up

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 2101-2101

10.1182/blood-2023-173970

Introduction Patients (pts) with multiple myeloma (MM) have a higher risk of progression/death following an inadequate response to frontline ASCT (van de Velde Eur J Haematol 2017). Therapies (Tx) with novel mechanisms of action may further improve response outcomes. Ide-cel previously demonstrated frequent, deep, and durable responses in KarMMa (Munshi N Engl J Med 2021) and significantly improved median progression-free survival (PFS) and overall response rate (ORR) versus standard regimens in KarMMa-3 (Rodríguez-Otero N Engl J Med 2023) in pts with triple-class-exposed relapsed and refractory MM. KarMMa-2 (NCT03601078) is a multicohort, phase 2, multicenter trial evaluating the efficacy and safety of ide-cel in pts with MM; cohort 2c included pts with NDMM who had an inadequate response to frontline Tx with ASCT. In cohort 2c, with a median follow-up of 27.9 months, ide-cel demonstrated deep and durable responses; complete response (CR) rate was 74.2% (ORR, 87.1%), with a 24-month PFS rate of 83.1% (Dhodapkar Blood 2022). Here, we report results with an additional 11.5 months of median follow-up for updated efficacy and safety data, and health-related quality of life (HRQoL) outcomes in cohort 2c. Methods Eligible pts had NDMM, received ≥ 3 cycles of induction Tx (including a proteasome inhibitor, an immunomodulatory agent, and dexamethasone), had &lt; very good partial response (VGPR) 70-110 days after ASCT (single/tandem), and had Eastern Cooperative Oncology Group performance status ≤ 1. Pts received a single infusion of ide-cel (dose range: 150-450 × 10 6 CAR+ T cells) after lymphodepletion and could receive maintenance Tx post-infusion at investigator's discretion. The primary endpoint CR rate and secondary endpoints ORR, duration of response (DOR), PFS, overall survival (OS), safety, and patient-reported outcomes on HRQoL, assessed via European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Core 30 Questionnaire (QLQ-C30) and EORTC Quality of Life Multiple Myeloma Module 20 Questionnaire (QLQ-MY20), are reported. The exploratory endpoint of minimal residual disease (MRD) negativity (sensitivity, 10 -5) is also reported. Results At data cutoff (May 3, 2023), with a median follow-up of 39.4 (range, 31.6-44.7) months, all 31 pts who were infused with ide-cel were alive; 28 (90.3%) remained in follow-up, with 3 (9.7%) having discontinued due to disease progression. The ORR and CR rates were 87.1% and 77.4%, respectively ( Table); best overall response in 1 pt improved from VGPR to stringent CR. The median DOR was not reached (NR; 95% CI, NR-NR), neither was median PFS (95% CI, 38.0-NR) or median OS (95% CI, NR-NR); the 36-month event-free rates were 80.9%, 76.8%, and 100.0%, respectively. In pts who did not receive lenalidomide (LEN) maintenance, 9 (29.0%) had disease progression; of the 8 pts who received LEN maintenance post ide-cel infusion, none experienced disease progression. At 36 months, MRD negativity was confirmed in 9/14 (64.3%) evaluable pts; all 9 achieved ≥ CR. In this extended follow-up, safety results were generally consistent with the previous data cutoff. All pts experienced ≥ 1 any-grade adverse event (AE), most commonly hematologic, including neutropenia (80.6%), anemia (38.7%), leukopenia (32.3%), and thrombocytopenia (29.0%); infection and infestation AEs occurred in 74.2% of pts. No grade 5 AEs were reported. Incidence of any-grade cytokine release syndrome (58.1%; no grade ≥ 3) was unchanged and there were no additional reports of parkinsonism since the previous report. Overall, HRQoL improved ( Figure) and MM disease symptoms were stable over time based on the EORTC QLQ-C30 and QLQ-MY20, respectively, following ide-cel treatment; by month 3, &gt; 75% of pts had improved or stable global health status/QoL. Conclusions Ide-cel continued to demonstrate deep, durable responses in pts with an inadequate response to frontline ASCT, no new safety signals were observed with extended follow-up, and no deaths were reported. No pts who received LEN maintenance post ide-cel experienced disease progression. Ide-cel treatment resulted in stable or improved HRQoL. Overall, ide-cel continued to demonstrate a favorable clinical benefit-risk profile in NDMM after ASCT. Study support 2seventy bio and Celgene, a Bristol-Myers Squibb Company.
Selinexor, Ixazomib, Pomalidomide and Dexamethasone in Functionally High-Risk Multiple Myeloma: Results from the Myeloma Developing Regimens Using Genomics (MyDRUG) Sub-Protocol Y3

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 3387-3387

10.1182/blood-2023-184949

Background: Multiple myeloma (MM) is characterized by somatic mutations involving cancer-associated genes. The MyDRUG trial was initiated to explore the efficacy of specific molecularly-targeted therapies in combination with a standard triplet combination in MM. Methods: MyDRUG (NCT03732703) is a genomically-guided umbrella trial for patients with functional high-risk MM, defined as early relapse following primary therapy (3 years for transplant with maintenance, 18 months without), with specific genetic abnormalities. Patients with no actionable mutation or mutations with allelic burden below 30% were randomly assigned to one of the “non-actionable” arms. Here we present the data for the Y3 arm which combines selinexor (60mg po days 1,8,15), ixazomib (4mg po days 1,8,15), pomalidomide (3mg po days 1-21) and dexamethasone (40mg po weekly) (Seli-IPD), given on a 28-day cycle. The primary objective of the Y3 sub-protocol was to evaluate the overall response rate (ORR) according to the International Myeloma Working Group consensus criteria. Secondary objectives included assessment of adverse events (AEs). Results: 17 patients were enrolled into the Y3 arm. The average age was 62 (51-79), 65% were male with a median of 29 months since initial diagnosis and a median of 2 prior lines of therapy. The ORR (&gt; PR) was 52.9% with a clinical benefit rate (&gt; MR) of 58.8%. The median progression free survival was 10.2 months ( 95% CI: 3.9; 12.9) with a median overall survival which has not yet been reached; with all 17 patients still alive at the current data cutoff. No dose-limiting toxicities were seen. Eight patients (47.1%) experienced a serious AE with 2 patients (11.8%) experiencing an AE leading to treatment discontinuation. Two patients (11.8%) required dose reductions. The most common non-hematologic AEs were fatigue, nausea and constipation; all of which were grade 1 and 2. Conclusions: In this platform study of patients with relapsed, functionally high-risk MM, patients who received Seli-IPd exhibited significant efficacy and a manageable AE profile. Furthermore, this provides an all-oral option for patients wishing to minimize their office visits and parenteral therapy administrations.