Relapsed/refractory Multiple Myeloma Patients Research Articles

Bispecific antibodies as bridging to BCMA CAR-T cell therapy for relapsed/refractory multiple myeloma.

Establishing a strategy for sequencing of T cell redirecting therapies for relapsed/refractory multiple myeloma (RRMM) is a pressing clinical need. We longitudinally tracked the clinical and immunological impact of bispecific T cell engaging antibodies (BsAb) as bridging therapy (BT) to subsequent BCMA-directed CAR-T cell therapies in 52 RRMM patients. BsAbs were a potent and safe option for BT, achieving the highest overall response rate (100%) to BT compared to chemotherapy, anti-CD38 or anti-SLAMF7 antibody based regimens (46%). We observed early CD4+CAR+ and delayed CD8+CAR+ T cell expansion in patients receiving BsAb as BT. In vitro cytotoxicity of CAR-T cells was comparable amongst BT options. Single-cell analyses revealed increased clonality in the CD4+ and CD8+ T cell compartments in patients with previous exposure to BsAbs at leukapheresis and on day 30 after CAR-T infusion. This study demonstrates the feasibility and efficacy of BT with BsAbs for CAR-T cell therapy in RRMM.

Clinical Efficacy of Isatuximab Plus Carfilzomib and Dexamethasone in Relapsed/Refractory Multiple Myeloma Patients.

Isatuximab, a novel anti-CD38 monoclonal antibody, is approved in combination with carfilzomib and dexamethasone (Isa-Kd) in relapsed/refractory multiple myeloma (RRMM) patients. Because of its recent introduction, real-world efficacy and safety are poorly reported. In this Italian multicenter real-life observational retrospective study, efficacy and safety of the Isa-Kd regimen were evaluated in a cohort of 103 RRMM patients. Overall response rate (ORR) was 85%, with stringent (sCR) or complete response (CR) in 18% of cases and very good partial response (VGPR) in 39%. Median PFS and OS were not reached within the study period, while 1-year PFS and OS were 72% and 77%, respectively. Hematological toxicities were observed in 42% of subjects, and cardiac toxicities occurred in 24% of cases. Moreover, we conducted a subanalysis on patients (N = 69) treated with Isa-Kd after one prior line of therapy, showing an ORR of 88%, with sCR + CR in 20% of subjects, VGPR in 46%, and PR in 22% of patients. In this group, median PFS and OS were not reached, while 1-year PFS and OS were 92% and 95%, respectively. In conclusions, our study confirmed Isa-Kd as an effective treatment option for RRMM with a manageable safety profile even in real-life settings.

BCMA-Directed MRD Detection as a Predictor of Relapse after BCMA CAR T in Multiple Myeloma

Background: Recent approvals of chimeric antigen receptor T-cells (CAR T) and bispecific antibody therapies offer new hope for relapsed refractory multiple myeloma (RRMM) patients, with superior efficacy over standard regimens observed in clinical trials. However, relapse after BCMA-directed therapy is common and requires further investigation. Patients and Methods: We conducted a retrospective cohort study on 57 RRMM patients treated with BCMA-directed CAR T. Only the patients who had an initial response and lost BCMA-expressing identified PC following CAR T infusion at Day 30 were included in the analysis. Multicolor flow cytometry (MFC) to detect BCMA + plasma cell (PC) re-emergence was performed on bone marrow samples at defined intervals and clinical responses were assessed using International Myeloma Working Group criteria. Results: The majority of patients achieved undetectable BCMA on MFC post-infusion, with subsequent BCMA+ PC re-emergence observed in 55% of cases. Notably, 91% of patients experiencing clinical relapse showed BCMA+ PC re-emergence, often preceding relapse. Early relapse (<6 months) was associated with earlier BCMA re-emergence. Conclusion: Early BCMA+ PC re-emergence may serve as a prognostic marker for clinical relapse post-BCMA CAR T therapy. Monitoring BCMA+ PC levels via MFC offers potential for early relapse detection and informed treatment decisions. Further studies, including novel BCMA-directed minimal residual disease (MRD) detection technologies, are warranted to validate these findings and refine RRMM management strategies.

The Real-World Outcomes of Relapsed/Refractory Multiple Myeloma Treated with Elotuzumab, Pomalidomide, and Dexamethasone.

Introduction: A combination of elotuzumab, pomalidomide, and dexamethasone (EPd) was approved for the treatment of relapsed/refractory multiple myeloma (RRMM) following the ELOQUENT-3 phase II clinical trial. However, the clinical experience with this therapy is still limited. In this retrospective study, we analyzed the efficacy and safety of EPd in a real-world cohort of RRMM patients. Patients and Methods: The medical records of 22 patients who received EPd for RRMM at Yokohama Municipal Citizen's Hospital (Japan) between January 2020 and July 2021 were reviewed. Results: The median age of our cohort was 73.5 years. The overall response rate was 55%. With a median follow-up of 20.2 months, the median progression-free survival (PFS) was 9.1 months (95% confidence interval [CI], 2.5-23.0 months). The median PFS was shorter in patients with a poor performance status (PS) than in those with favorable PS (2.5 vs. 10.8 months; p < 0.01). Patients with prior daratumumab had significantly shorter PFS than those without prior daratumumab (2.1 vs. 23.0 months; p < 0.01). Additionally, patients with prior pomalidomide had significantly shorter PFS (1.7 vs. 10.3 months; p < 0.01). In the multivariate analysis, poor PS (hazard ratio [HR] = 4.1, 95% CI: 1.1-15.6; p = 0.04) and prior exposure to daratumumab (HR = 3.8, 95% CI: 1.1-13.8; p = 0.04) remained significantly associated with shorter PFS. Conclusions: The results of our study suggest that EPd is an active and well-tolerated regimen in RRMM, even in real-world patients. Furthermore, EPd may be useful, especially in daratumumab-naïve patients.

A CD38/CD3xCD28 trispecific T‐cell engager as a potentially active agent in multiple myeloma patients relapsed and/or refractory to anti‐CD38 monoclonal antibodies

SummaryThere is accumulating evidence of BCMA and GPRC5D loss after treatment with T‐cell redirecting therapies in patients with relapsed/refractory multiple myeloma (RRMM). While complete CD38 loss is not observed upon relapses after treatment with anti‐CD38 monoclonal antibodies (mAb), there is downregulation of surface CD38 expression and decreased number and function of NK cells, which renders these patients resistant to retreatment with anti‐CD38 mAb. Here, we provide preclinical evidence that RRMM patients previously exposed to anti‐CD38 mAb could benefit from T‐cell‐based immunotherapy that depend less on CD38 antigen density and NK‐cell activity, such as the novel CD38/CD3xCD28 trispecific T‐cell engager, SAR442257.

Efficacy of CARVYKTI in CARTITUDE-4 versus other conventional treatment regimens for lenalidomide-refractory multiple myeloma using inverse probability of treatment weighting.

Aim: The phase III randomized controlled trial (RCT) CARTITUDE-4 (NCT04181827) demonstrated superiority of CARVYKTI (ciltacabtagene autoleucel; cilta-cel) over daratumumab, pomalidomide and dexamethasone (DPd) and pomalidomide, bortezomib and dexamethasone (PVd) for relapsed/refractory multiple myeloma (RRMM) patients who have received one to three prior line(s) of therapy (LOT[s]) including an immunomodulatory agent and a proteasome inhibitor, and are refractory to lenalidomide. These analyses estimate the relative efficacy between cilta-cel and other common treatment regimens, for which no direct comparative evidence is available. Materials & methods: Patient data were available from the CARTITUDE-4, CASTOR, CANDOR and APOLLO RCTs. Imbalances between cohorts on key patient characteristics were adjusted for using inverse probability of treatment weighting (IPTW). Relative efficacies were estimated with response rate ratios (RRs) and 95% confidence intervals (CIs) for overall response rate (ORR), very good partial response or better rate (≥VGPR) and complete response or better rate (≥CR), and with hazard ratios (HRs) and 95% CIs for progression-free survival (PFS). Sensitivity analyses using different analytical methods and additional covariates were explored. Results: Key characteristics were well balanced across cohorts after IPTW. Cilta-cel showed statistically significant benefit in PFS (HRs: 0.11-0.51), ≥VGPR (RRs: 1.51-5.13) and ≥CR (RRs: 2.90-35.24) versus all comparators, and statistically significant improvements in ORR over most comparator regimens (RRs: 1.22-1.90). Results were consistent across sensitivity analyses. Conclusion: Cilta-cel demonstrated benefit over other common treatment regimens, highlighting its potential to become a new standard of care option for lenalidomide-refractory RRMM patients with one to three prior LOT(s). These comparisons help to demonstrate the improved efficacy of cilta-cel in countries where the standard of care may differ from DPd/PVd.

Efficacy of ixazomib, lenalidomide, dexamethasone regimen in daratumumab-exposed relapsed/refractory multiple myeloma patients: A retrospective analysis.

We performed retrospective analysis of relapsed/refractory multiple myeloma (RRMM) patients previously exposed to daratumumab treated with ixazomib, lenalidomide, dexamethasone (IRd) regimen in real clinical practice. Our aim was to evaluate efficacy of IRd in these patients and select a subset of patients that would benefit from this treatment the most. In total, we analyzed 43 daratumumab-exposed RRMM patients treated in our center. Minimal response or better was achieved by 53.5% of patients from the cohort. Median progression free survival (PFS) was 4.56 months (95% CI: 2.56, 8.03) and median overall survival (OS) was 28.92 months (95% CI: 5.4, NR). Duration of response (DOR) was evaluable in 28 patients and reached a median of 21.3 months (95% CI: 6.85, NR). Next, we evaluated hazard ratios (HR) for OS and PFS. There was improved OS in patients that were not-triple refractory or worse (HR = 0.39, 95%Cl (0.14; 1.10), p = .07) and in patients, that had less than three previous lines of treatment (LOT) (HR = 0.13, 95%Cl (0.03; 0.6) p = .003). Similar to OS, there was improved PFS in patients, that were not triple-refractory or worse (HR = 0.52, 95%Cl (0.25; 1.10), p = .08). We concluded, that the best survival benefit for RRMM patients pretreated with daratumumab to IRd regimen was observed in patients that were not triple-refractory and had less than three previous lines of treatment (LOT). The DOR in these patients was 21.3 months (95% CI: 6.85, NR).

Treatment pattern among patients with relapsed/refractory multiple myeloma (RRMM) who had received pomalidomide-based regimens in Taiwan

ABSTRACT Background/purpose The treatment landscape of relapsed/refractory multiple myeloma (RRMM) is rapidly evolving in Taiwan. The present study aimed to assess the treatment patterns among RRMM patients in Taiwan. Methods This retrospective, chart review-based, non-interventional study collected data on RRMM patients (≥20 years old) receiving pomalidomide-based treatment between January 2017 and December 2020 across five sites in Taiwan. Results Median age of the study population was 65.6 years. Approximately 75% patients received a doublet regimen and 25% were on a triplet regimen. Disease progression was the most common cause for switching to pomalidomide-based treatments in doublet (71.2%) and triplet (58.3%) groups. Patients in doublet and triplet groups (>80%) received 4 mg pomalidomide as a starting dose. Overall response rate (ORR: 31.5% and 45.8%) and median progression-free survival (PFS: 4.7 and 6.8 months) were reported in the doublet and triplet regimen. Doublet regimen was discontinued mainly due to disease progression or death (78.1%); however, triplet regimen patients mainly terminated their treatment due to reimbursement limitations (29.2%). Healthcare resource utilization (HRU) was comparable between doublet and triplet groups. Conclusion In Taiwan, half of RRMM patients received pomalidomide-based triplet regimens. Triplet regimens showed a trend towards better outcomes with longer PFS and higher response rates compared to doublets. Notably, the duration of triplet use is influenced by reimbursement limitations. This study provides insight into RRMM treatment patterns in Taiwan and the findings suggest that triplet regimens may be a better alternative than doublet regimens.

Biological relapse in multiple myeloma: Outcome and treatment strategies in a Spanish real-world setting.

Recommendations regarding the best time to start treatment in patients with relapsed/refractory multiple myeloma (RRMM) after biological relapse/progression (BR) are unclear. This observational, prospective, multicenter registry aimed to evaluate the impact on time to progression (TTP) of treatment initiation at BR versus at symptomatic clinical relapse (ClinR) based on the Spanish routine practice in adult patients with RRMM. Patients had two or less previous treatment lines and at least one previous partial response. Baseline characteristics and treatment outcomes were recorded, and survival was analyzed. Of 225 patients, 110 were treated at BR (TxBR group) and 115 at ClinR (TxClinR group) according to the investigators'criteria. The proportion of patients with higher ECOG, previous noncomplete remission (CR), and second relapse were significantly higher in the TxBR group compared to the TxClinR group. TheTxClinR group showed improved outcomes, including TTP, compared to the TxBR group. Progression-free survival increased in the TxClinR group (56.2 months) compared to the TxBR group (32.5 months) (p = 0.0137), and median overall survival also increased (p = 0.0897). Median TTP was significantly longer in patients relapsing from a CR (50.4 months) and in their first relapse (38.7 months) compared to those relapsing from a non-CR response (32.9 months) and in their second relapse (25.2 months). Physicians seemed to start treatment earlier in RRMM patients with poor prognosis features. Previous responses to anti-MM treatment and the number of prior treatment lines were identified as prognosis factors, whereby relapse from CR and first relapse were associated with a longer time to progression.

Phase I study of TQB3602, an oral proteasome inhibitor, in relapsed and refractory multiple myeloma.

TQB3602 is a novel orally bioavailable proteasome inhibitor. This study is thefirst-in-human phase I clinical trial to evaluate the safety, tolerability, pharmacokinetics, and preliminary efficacy of TQB3602 in relapsed/refractory multiple myeloma (RRMM). This is a multicenter phase I clinical trial consisting of the 3+3 dose-escalation phase and dose expansion phase. Patients with MM who have received ≥2 prior antimyeloma therapies were enrolled. TQB3602 is administered at a dose of 0.5~7mg on days 1, 8, 15 in 28-day cycle. Twenty-five RRMM patients who relapsed or failed ≥2 lines of therapies were enrolled in the dose escalation phase. Two patients in the 7.0 mg dose group developed dose-limiting toxicity events (one with grade 2 peripheral neuropathy [PN] complicated by pain and one with diarrhea and abdominal pain), leading to a maximum tolerated dose of 6.0 mg. Any-grade adverse events (AEs) occurred in 24 (96.0%) patients, while grade ≥3 AEs occurred in 13 (52.0%). The most common grade ≥3 AEs was anemia (6, 24.0%). The incidence rate of PN was 16% with no grade ≥3 PN occurred. TQB3602 was rapidly absorbed, resulting in a time-to-plasma peak concentration of 0.8-1.5 h. The mean half-life was approximately 82 h. The AUClast and Cmax were approximately 1.9 times higher on day 15 than on day 1. Among 22 response-evaluable patients, 63.7% achieved stable disease or better. TQB3602 is well tolerated, with a favorable neurotoxicity profile, and has shown preliminary efficacy in patients with RRMM. The anticipated therapeutic dose was 6 mg and was adopted for an ongoing dose-expansion phase.

Elotuzumab plus pomalidomide and dexamethasone in relapsed/refractory multiple myeloma: Extended follow-up of a multicenter, retrospective real-world experience with 321 cases outside of controlled clinical trials.

The ELOQUENT-3 trial demonstrated the superiority of the combination of elotuzumab, pomalidomide, and dexamethasone (EloPd) in terms of efficacy and safety, compared to Pd in relapsed/refractory multiple myeloma (RRMM), who had received at least two prior therapies, including lenalidomide and a proteasome inhibitor. The present study is an 18-month follow-up update of a previously published Italian real-life RRMM cohort of patients treated with EloPd. This revised analysis entered 319 RRMM patients accrued in 41 Italian centers. After a median follow-up of 17.7months, 213 patients (66.4%) experienced disease progression or died. Median progression-free survival (PFS) and overall survival (OS) were 7.5 and 19.2months, respectively. The updated multivariate analysis showed a significant reduction of PFS benefit magnitude both in advanced International Staging System (ISS) (II and III) stages and previous exposure to daratumumab cases. Instead, advanced ISS (II and III) stages and more than 2 previous lines of therapy maintained an independent prognostic impact on OS. Major adverse events included grade three-fourths neutropenia (24.9%), anemia (13.4%), lymphocytopenia (15.5%), and thrombocytopenia (10.7%), while infection rates and pneumonia were 19.3% and 8.7%, respectively. A slight increase in the incidence of neutropenia and lymphocytopenia was registered with longer follow-up. In conclusion, our real-world study still confirms that EloPd is a safe and possible therapeutic choice for RRMM. Nevertheless, novel strategies are desirable for those patients exposed to daratumumab.

Ixazomib plus daratumumab and dexamethasone: Final analysis of a phase 2 study among patients with relapsed/refractory multiple myeloma.

Novel therapies have improved outcomes for multiple myeloma (MM) patients, but most ultimately relapse, making treatment decisions for relapsed/refractory MM (RRMM) patients increasingly challenging. We report the final analysis of a single-arm, phase 2 study evaluating the oral proteasome inhibitor (PI) ixazomib combined with daratumumab and dexamethasone (IDd; NCT03439293). Sixty-one RRMM patients (ixazomib/daratumumab-naïve; 1-3 prior therapies) were enrolled to receive IDd (28-day cycles) until disease progression/unacceptable toxicity. Median age was 69 years; 14.8% of patients had International Staging System stage III disease; 14.8% had received three prior therapies. Patients received a median of 16 cycles of IDd. In 59 response-evaluable patients, the overall response rate was 64.4%; the confirmed ≥very good partial response (VGPR) rate (primary endpoint) was 30.5%. Rates of ≥VGPR in patient subgroups were: high-risk cytogenetics (n = 15, 26.7%), expanded high-risk cytogenetics (n = 24, 29.2%), aged ≥75 years (n = 12, 16.7%), lenalidomide-refractory (n = 21, 28.6%), and prior PI/IMiD therapy (n = 58, 31.0%). With a median follow-up of 31.6 months, median progression-free survival was 16.8 months (95% confidence interval: 10.1-23.7). Grade ≥3 treatment-emergent adverse events (TEAEs) occurred in 54.1% of patients; 44.3% had serious TEAEs; TEAEs led to dose modifications/reductions/discontinuations in 62.3%/36.1%/16.4%. There were five on-study deaths. Any-grade and grade ≥3 peripheral neuropathy occurred in 18.0% and 1.6% of patients. Quality of life was generally maintained throughout treatment. IDd showed a positive risk-benefit profile in RRMM patients and was active in clinically relevant subgroups with no new safety signals.

Absolute Lymphocyte Count and Outcomes of Multiple Myeloma Patients Treated with Idecabtagene Vicleucel: The US Myeloma Immunotherapy Consortium Real- World Experience

Idecabtagene vicleucel (ide-cel) has shown impressive efficacy in relapsed/refractory multiple myeloma (RRMM). This study aimed to investigate the impact of absolute lymphocyte count (ALC) on the survival outcomes of RRMM patients treated with standard of care (SOC) ide-cel. Data were collected retrospectively from 11 institutions in the U.S. Impact of ALC parameters including pre-apheresis (pre-A), pre-lymphodepletion (pre-LD), absolute and percent difference from pre-A to pre-LD on clinical outcomes after ide-cel were examined using survival analysis. A new ALC profile was created based on univariate analysis that comprises 3 groups: normal (≥1 × 109/L) pre-LD ALC (LDN), low (<1 × 109/L) pre-LD ALC (LDL) + percent reduction <37.5 (%RL), and LDL ALC + percent reduction ≥37.5 (%RH). A total of 214 SOC ide-cel recipients were included in this analysis. The median patient age was 64 years (interquartile range [IQR], 57 to 69 years), median number of prior therapies was 6 (IQR, 5 to 9), and median duration of follow-up was 5.4 months (IQR, 2.1 to 8.3 months). Most patients had both low pre-A ALC (75.3%) and pre-LD ALC (77.2%), and the reduction from pre-A to pre-LD (median, .65 to .55 × 109/L) was statistically significant. Univariate analysis showed that the LDL + %RH group had significantly worse progression-free survival (PFS) and overall survival (OS) compared to the LDL + %RL and LDN ALC groups (6-month PFS: 40% versus 67.6% and 60.9%; 6-month OS: 69.5% versus 87% and 94.3%). In multivariable analysis, after adjusting for age, performance status, cytogenetic risk, use of bridging therapy, and extramedullary disease, PFS did not maintain its statistical significance; however, OS remained significantly worse for LDL + %RH group compared to the LDN ALC group (hazard ratio [HR], 4.3; 95% confidence interval [CI], 1.1 to 17), but the difference between the LDL + %RH versus %RL groups was not statistically significant (HR, 1.7; 95% CI, .8 to 4.0). Our findings indicate that low pre-LD ALC with high %R from pre-A to pre-LD was associated with inferior survival outcomes, particularly OS, in patients who received SOC ide-cel.

Age-related differences in information-seeking behaviors of patients with multiple myeloma.

e19523 Background: For patients with relapsed refractory multiple myeloma (RRMM), obtaining essential disease information for effective self-advocacy and decision-making is challenging, exacerbated by age-related educational barriers and issues related to cultural resources. This study evaluated age-related preferences of patient education resource utilization in RRMM patients. Methods: This survey was conducted on HealthTree Cure Hub, a patient-driven platform designed to efficiently share clinical insights from myeloma specialists, help patients navigate their disease, and contribute to research. The analysis focuses on evaluating the use of 16 different resources and age-related differences among patients with RRMM. Scales included: 1-to-5 for usage (1 - never, 2 - almost never, 3 - occasionally/sometimes, 4 - almost every time, 5 - every time) and 1-to-6 for education (some high school to a graduate degree). Results: Of the 688 participants, 289 had available birth dates and were included in the analysis. The &lt;65 cohort (Y) was 57±6 years old (yo), and the ≥ 65 cohort was 71±5 yo at the time of the survey. The ≥65 cohort (O) was more educated (O: 5.2±1.0; Y: 4.8±1.3, p&lt;0.05), increased their utilization of webinars with time (1st change: 3.1±1.2; &gt; 1 changes: 3.4±1.3, p&lt;0.05) and review of NCCN, ASCO, mSMART, or other blood cancer society guidelines over time (1st change: 2.1±1.2 ; &gt;1 changes: 2.4±1.4, p&lt;0.05). Additionally, the older patients used pamphlets (printed or PDF) created by pharmaceutical companies more than younger patients (O: 2.4±1.1; Y: 2.1±1.2, p&lt;0.05), however, this difference decreased for &gt;1 changes in therapy (Y: 2.1±1.2; O: 2.2±1.2, p&gt;0.05). The older patients utilized social media (non-myeloma expert posts) less at &gt;1 changes in therapy (O: 1.5±0.8; Y: 2.0±1.0, p&lt;0.05), with 69% (n = 69) of the older cohort reported never using this resource, while only 44% (n = 18) of the younger patients reported never using it. The &lt;65 cohort consulted family members, friends or loved ones more than the ≥65 cohort for &gt;1 changes in therapy (Y: 2.5±1.5; O: 1.9±1.1, p&lt;0.05). In addition, the younger patients increased the utilization of medical journal articles with subsequent changes in therapy (2.8±1.2 to 3.0±1.2, p&lt;0.05). Conclusions: The survey revealed that older patients increasingly engaged in webinars and consulted cancer society guidelines with subsequent changes in therapy. While younger patients increased their use of medical journals and more often consulted with their family, friends and loved ones. Both groups demonstrated a wide range of resources (16) used to build their knowledge of myeloma. These findings indicate a desire among patients to comprehend their disease, utilizing diverse resources for information and gaining more knowledge over time.

Characterization of the BCMA epitope bound by BCMA-CD3 T cell engager elranatamab.

7546 Background: Elranatamab is a BCMA-CD3 bispecific antibody with an accelerated approval in the US and EU for relapsed/refractory multiple myeloma (RRMM). Elranatamab binds to CD3 on T cells and BCMA on MM tumor cells; this dual binding results in T cell activation, cytokine release, and tumor cell killing. Engagement of the BCMA surface receptor by its ligands, APRIL and BAFF, mediates plasma cell proliferation and survival. Elevated BCMA, as well as BAFF and APRIL are present in MM patients, yet in vitro functional assays have shown physiologically relevant soluble APRIL or BAFF concentrations did not significantly impact elranatamab activity. Moreover, emerging clinical data from relapsed patients has identified novel, yet relatively rare BCMA protein mutations that may impact BCMA ligand or targeted modality binding. Here we characterized the BCMA binding affinity, evaluated the impact on BCMA binding to BAFF and APRIL interactions, and identified the BCMA binding epitope. We also generated a model from crystal structure data to map reported BCMA mutations identified in patients. Methods: Elranatamab binding affinity to recombinant human BCMA and characterization of BAFF and APRIL interactions with elranatamab-bound BCMA were calculated via SPR at 37˚C with a classical sandwich format. The elranatamab BCMA binding epitope was identified by a co-crystal structure with a parental anti-BCMA Fab that has identical CDR sequences to elranatamab. Alpha-fold modeling was used to map identified BCMA mutations on the antibody/BCMA interface. Results: Elranatamab binds to BCMA with higher affinity (~38 pM) compared to reported binding affinities of BAFF (μM range) and APRIL (nM range) ligands. The identified elranatamab epitope largely overlaps with known ligand epitopes, supporting that elranatamab higher affinity BCMA binding blocks ligand binding. Alpha fold modeling of four recently reported rare BCMA mutations shows that they lie along the binding interface. Conclusions: Due to its high affinity for BCMA, elranatamab potency is unlikely to be impacted by elevated levels of soluble BAFF or APRIL in RRMM patients. Future studies are needed to characterize the impact of emerging MM patient BCMA mutations on the binding and function of anti-BCMA targeting modalities, particularly given the small extracellular domain of BCMA available for therapeutic targeting and the highly overlapping binding epitopes reported for approved BCMA agents.

The role of patient-driven education in decision-making for relapsed/refractory multiple myeloma.

e19532 Background: This study examines decision-making resources and outcomes among patients with relapsed/refractory multiple myeloma (RRMM). The study aimed to identify shifts in resource utilization over time and evaluate the relationships of these with patient education outcomes. Methods: Using HealthTree Cure Hub, a retrospective cross-sectional survey was conducted exploring the experiences of RRMM patients undergoing therapy changes. Likert scales assessed educational resource utilization frequency (1-never to 5-all the time), healthcare team explanations rating (1-very poor to 5-very good), comfort level with final treatment decision (1-very uncomfortable to 5 - very comfortable), education satisfaction (1-very dissatisfied to 5-very satisfied) and time given and used to make a treatment decision. Results: 294 RRMM were included with a mean age of 66±9, 53% were female, and 49% had a graduate level education. Of 219 demographics respondents, 91% were white. For the first change in treatment the top educational resources were: 1) doctor/medical team recommendations (91%), 2) patient advocacy myeloma websites or resources (58%), 3) Google search (40%), 4) webinars (38%), and 5) online videos with experts (37%) (%, all or almost every time). Use of an additional three educational resources increased: 1) articles in medical journals (2nd change: 2.3±1.1; &gt; 3 changes: 3.1±1.3), 2) NCCN, ASCO, mSMART or other blood cancer society guidelines (1st change: 2.0±1.1; &gt; 1 changes: 2.3±1.3), and 2) social media posts from myeloma experts (1st change: 2.5±1.2; &gt; 1 change: 2.7±1.3), p &lt; 0.05. The patients' rating of their care teams’ explanations of the treatment options was on average good (4.0±1.1) at 1st change in therapy with (95% of patients rating the explanations as acceptable or better) and this improved at &gt; 3 changes in therapy (4.4±0.7, p &lt; 0.05), with 100% rating these as acceptable or better. Correspondingly, patients' comfort level with their final treatment decision (4.3±0.8) was related to the care team's explanation rating (r = 0.406, p &lt; 0.001) and overall level of treatment education satisfaction (4.0±0.8, r = 0.503, p &lt; 0.001), but it was not related to time given (4.7±9.3 wk) or used (2.2±5.4 wk) to make the treatment decision. Conclusions: While doctor/medical team recommendations remain central, RRMM patients increasingly turn to a diverse set of educational resources as they gain more experience. This is likely driven by an effort to reach a comfortable treatment decision and to obtain a satisfactory disease and treatment education level. Patients' utilization of patient advocacy websites, medical journals, society guidelines, and social media expert posts indicates a broadening of resources used to build an information base. Acknowledging this evolving paradigm is vital for understanding viable avenues for patient engagement to enhance treatment choice and decision making.

The effect of care team-patient relationship on decision-making in relapsed/refractory multiple myeloma.

e19530 Background: Understanding patient involvement in shared decision making is critical for informed decision-making for relapsed/refractory multiple myeloma (RRMM) patients. This study explored the relationships between care teams and patients, who patients talk to and quantify the level of involvement, satisfaction, and comfort in the process of reaching a final change in treatment decision. Methods: HealthTree Cure Hub (PMID: 35271305) was used to conduct a survey for RRMM patients for their first change of therapy decision. Five-point Likert scales were used (1-Not at All Influential to 5-Extremely Influential; 1-Very Satisfied to 5-Very Dissatisfied), along with dichotomous and categorical choices. Results: 294 patients with RRMM were included with a mean age of 66±9, 53% were female, and 49% had graduate level education. Of 219 demographics respondents, 91% were white. Of the people patients talked to, the most influential individuals ranked by somewhat to extremely influential were: 1) myeloma specialist (84%), 2) community hematologist/oncologist (69%), and 3) spouse, partner or significant other (56%). Additionally, 67% of patients talked with nurses, PAs, or RNAs, with 49% finding them somewhat to extremely influential. Seeking a second opinion from a myeloma specialist was reported by 34% of patients and 50% of patients reported talking to other patients about treatment decisions. Patients varied in their description of their relationship/communication approach with their doctor: the doctor makes recommendations, the patients ask questions and they discuss preferences, then 1) patient proposes ideas and the decision is made together (37%), 2) then the patient makes the final decisions (21%) and 3) then the patient follows the doctor’s suggestions (14%). Importantly, a weak positive relationship existed between these levels of patient involvement in the treatment decisions and their involvement-satisfaction in choosing a treatment (r = 0.251, p &lt; 0.001). About half of patients (51%) followed their care team recommendations without changes, while 31% opted for significant alterations, and 19% chose a modified option. Most patients reported making the final decision (59%), followed by their doctor (40%), and the minority reported a caregiver or partner (1%). Conclusions: This study identified that about half of patients engage in a collaborative and active decision-making process, which was related to their involvement-satisfaction of the treatment decision. Patients actively engaged with various individuals, including myeloma specialists, community hematologists/oncologists, and spouse/partners. Notably, discussions with nurses, PAs, and RNAs played a significant role, along with interactions with peers. Taken together a multifaceted engagement highlights the active role of patients in determining their treatment paths within a complex healthcare network.

Impact of Extraosseous Extramedullary Disease on Outcomes of Patients with Relapsed-Refractory Multiple Myeloma receiving Standard-of-Care Chimeric Antigen Receptor T-Cell Therapy

The presence of extramedullary disease (EMD) has been associated with poor outcomes in patients with relapsed-refractory multiple myeloma (RRMM). Herein, we report the outcomes of RRMM patients who were treated with standard-of-care (SOC) chimeric antigen receptor (CAR) T-cell therapy and had active extraosseous EMD before the infusion. Data were retrospectively collected from patients at three US institutions with the intent to receive SOC CAR T. Responses were assessed per the International Myeloma Working Group criteria. A total of 152 patients proceeded with infusion, of whom 47 (31%) had EMD (EMD group) and 105 (69%) did not (non-EMD group). Baseline patient characteristics were comparable between the two groups. The EMD group had a higher incidence of high-grade CRS, steroid and anakinra use, and thrombocytopenia on day +30 compared to the non-EMD group. In addition, the EMD group had an inferior overall response rate (58% vs 96%, p < 0.00001), median progression-free survival (PFS) (5.1 vs 12.4 months; p < 0.0001), and overall survival (OS) (12.2 vs 27.5 months; p = 0.00058) compared to the non-EMD group. We further subdivided the non-EMD patients into those with paramedullary disease (PMD-only group, n = 26 [17%]) and those with neither EMD nor PMD (bone marrow-contained group or BM-only group, n = 79 [52%]). Patients with PMD-only had similar median PFS (11.2 vs 13.6 months, p = 0.3798) and OS (not reached [NR] vs 27.5 months, p = 0.6446) compared to patients with BM-only disease. However, patients with EMD exhibited inferior median PFS (5.1 vs 13.6 months, p < 0.0001) and OS (12.2 vs 27.5, p = 0.0008) compared to patients in the BM-only group. Treatment with SOC CAR T yielded meaningful clinical outcomes in real-world RRMM patients with extraosseous EMD, though responses and survival outcomes were suboptimal compared to patients without EMD. The presence of only EMD but not PMD was associated with significantly worse survival outcomes following the CAR T infusion.

Unlocking hope: talquetamab in multiple myeloma treatment: a bispecific breakthrough targeting CD3 and GPRC5D

Multiple myeloma (MM) presents a significant global health burden, with disparities in incidence and outcomes reflecting challenges in recognition and treatment. Talquetamab, a bispecific CD3 T-cell engager targeting G-protein coupled receptor family C group 5 member D (GPRC5D), has emerged as a promising immunotherapy for relapsed/refractory MM (RRMM). In August 2023, talquetamab received accelerated approval from the US FDA for RRMM treatment, followed by conditional marketing authorization from the EMA. Clinical trials demonstrated talquetamab's efficacy, with overall response rates (ORR) of 69% and 76% in heavily pretreated RRMM patients. The phase I monumenTAL-1 trial showcased talquetamab's effectiveness, particularly in high-risk MM and extramedullary disease, with ORRs around 71-74%. Subsequent phase 2 results reaffirmed its efficacy, even in patients with prior T-cell redirection therapies. Combination therapy with daratumumab further enhanced talquetamab's efficacy, addressing concerns of T cell exhaustion. Pharmacokinetic studies revealed sustained responses and manageable adverse events with subcutaneous administration, facilitating convenient dosing regimens. However, talquetamab carries risks of cytokine release syndrome (CRS) and neurologic toxicity, necessitating close monitoring and prompt management. Common adverse events included fever, CRS, musculoskeletal pain, and infections, although severe events were infrequent. Vigilant management strategies, including prophylactic measures and supportive care, mitigate these risks. In conclusion, talquetamab represents a significant advancement in RRMM treatment, offering a promising avenue for T-cell redirection therapy. Ongoing research aims to optimize treatment sequencing and combination strategies, fostering improved outcomes for MM patients. Continued investigation will refine the strategic integration of talquetamab and other immunotherapies, paving the way for enhanced treatment efficacy and patient care in RRMM.

Target trial emulation of carfilzomib safety among patients with relapsed/refractory multiple myeloma using a nationwide observational data in Korea

PurposeCarfilzomib, commonly used for relapsed/refractory multiple myeloma (RRMM), has been associated with various adverse events in randomized controlled trials (RCTs). However, real-world safety data for a more diverse population are needed, as carfilzomib received expedited approval. This study aimed to evaluate carfilzomib’s safety in Korea by comparing new users of KRd (carfilzomib, lenalidomide, and dexamethasone) to Rd (lenalidomide and dexamethasone) using a nationwide administrative claims database.MethodsThe retrospective cohort study utilized target trial emulation, focusing on adverse events in various organ systems similar to the ASPIRE trial.ResultsThis study included 4,580 RRMM patients between 2007 and 2020, and the KRd group showed significantly higher risks of hematologic adverse events (anemia, neutropenia, thrombocytopenia) and some non-hematologic adverse events (cough, hypokalemia, constipation, hypertension, heart failure) compared to the Rd group. Among non-hematologic adverse events, cardiovascular events (heart failure [HR 2.04; 95% CI 1.24–3.35], hypertension [HR 1.58; 95% CI 1.15–2.17]) had the highest risk in the KRd group.ConclusionThe safety profile of carfilzomib in Korean patients was similar to previous RCTs. Therefore, caution should be exercised when using carfilzomib in Asian individuals with RRMM due to the increased risk of cardiovascular adverse events.