Toxicity of CAR T-Cell Therapy for Multiple Myeloma.

BACKGROUND: Idecabtagene vicleucel (ide-cel) and ciltacabtagene autoleucel (cilta-cel) are novel chimeric antigen receptor (CAR)-T cell therapies targeting B-cell maturation antigen (BCMA), and both have recently gained approval by the U.S. Food Drug Administration (FDA) for treatment of relapsed and refractory multiple myeloma (RRMM). SUMMARY: These therapies offer unprecedented responses in RRMM but present new challenges including cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), non-ICANS neurotoxicity, cytopenias, infections, and hypogammaglobulinemia. KEY MESSAGES: In the evolving CAR-T landscape, a primary objective is to develop innovative strategies for managing associated toxicities. Through meticulous exploration of underlying mechanisms and tailored interventions, we aim to enhance safety and enable broader outpatient utilization. Refinement of protocols, biomarker identification, and robust monitoring are imperative for sustained efficacy. This comprehensive approach guarantees the continuous advancement and optimization of CAR-T therapy.

Applying the EHA/EBMT grading for ICAHT after CAR-T: comparative incidence and association with infections and mortality.

ABSTRACT: Cytopenias represent the most common side effect of CAR T-cell therapy (CAR-T) and can predispose for severe infectious complications. Current grading systems, such as the Common Terminology Criteria for Adverse Events (CTCAE), neither reflect the unique quality of post-CAR-T neutrophil recovery, nor do they reflect the inherent risk of infections due to protracted neutropenia. For this reason, a novel EHA/EBMT consensus grading was recently developed for Immune Effector Cell-Associated HematoToxicity (ICAHT). In this multicenter, observational study, we applied the grading system to a large real-world cohort of 549 patients treated with BCMA- or CD19-directed CAR-T for refractory B-cell malignancies (112 multiple myeloma [MM], 334 large B-cell lymphoma [LBCL], 103 mantle cell lymphoma [MCL]) and examined the clinical sequelae of severe (≥3°) ICAHT. The ICAHT grading was strongly associated with the cumulative duration of severe neutropenia (r = 0.92, P < .0001), the presence of multilineage cytopenias, and the use of platelet and red blood cell transfusions. We noted an increased rate of severe ICAHT in patients with MCL vs those with LBCL and MM (28% vs 23% vs 15%). Severe ICAHT was associated with a higher rate of severe infections (49% vs 13%, P < .0001), increased nonrelapse mortality (14% vs 4%, P < .0001), and inferior survival outcomes (1-year progression-free survival: 35% vs 51%, 1-year overall survival: 52% vs 73%, both P < .0001). Importantly, the ICAHT grading demonstrated superior capacity to predict severe infections compared with the CTCAE grading (c-index 0.73 vs 0.55, P < .0001 vs nonsignificant). Taken together, these data highlight the clinical relevance of the novel grading system and support the reporting of ICAHT severity in clinical trials evaluating CAR-T therapies.

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

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

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

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

Simple Score of Albumin and CRP Predicts High-Grade Toxicity in Patients with Multiple Myeloma Receiving CAR-T Therapy.

Administration of chimeric-antigen receptor T-cell (CAR-T) therapy is complex and associated with unique toxicities. Identifying patients at risk for inferior outcomes is important for individualized management. The Glasgow-prognostic score (GPS) is a simple score shown to be highly prognostic of outcomes in the setting of traditional chemotherapy or checkpoint inhibitor administration. We sought to evaluate the value of the GPS to predict outcomes of patients with relapse refractory multiple myeloma (RRMM) receiving anti-BCMA CAR-T therapy. We included all patients treated with commercial CAR-T therapy for RRMM between 5/1/2021 and 2/1/2023 at the Moffitt Cancer Center. The GPS (CRP >1 mg/dL, 1 point; albumin <3.5, 1 point) was calculated for all patients at lymphodepletion (day -6) and patients were grouped as high-risk GPS (score = 2) or low-risk GPS (0 or 1). The primary endpoint was overall survival (OS) at day 100. A total of 139 pts were included, with a median follow-up of 6.7 months (95% CI, 6.2 to 8.9 months). Pts were treated with either idecabtagene vicleucel (83%) or ciltacabtagene autoleucel (17%). In total, 14% were classified with high-risk GPS, with significantly increased risk for grade 3 cytokine release syndrome (P = .003) and ICANS of any grade (P < .001). Patients in the high-risk GPS group had significantly lower day-100 OS (68.4% versus 97.3%, P < .001), OS at 6 months (56% versus 91.8% P = .0019) and PFS at 6 months (38.3% versus 72.3%, P = .03). The association of GPS with day-100 OS remained significant in a multivariable model. In conclusion, the GPS identifies a group of high-risk patients with RRMM receiving CAR-T therapy who experience increased rates of immune-mediated toxicity and are at higher risk for early mortality.

The Impact of Outpatient versus Inpatient Administration of CAR-T Therapies on Clinical, Economic, and Humanistic Outcomes in Patients with Hematological Cancer: A Systematic Literature Review.

Although chimeric antigen receptor (CAR)-T cell therapies are typically administered in the inpatient setting, outpatient administration is rapidly expanding. However, there is limited summarized evidence comparing outcomes between outpatient and inpatient administration. This systematic literature review aims to compare the safety, efficacy, quality of life (QoL), costs, and healthcare resource utilization (HCRU) outcomes in patients with hematological cancer who are administered CAR-T therapy in an outpatient versus an inpatient setting. Publications (2016 or later) that reported the outcomes of interest in patients treated with a CAR-T therapy in both outpatient and inpatient settings, or only the outpatient setting, were reviewed. In total, 38 publications based on 21 studies were included. Safety findings suggested the comparable frequency of adverse events in the two settings. Eleven studies that reported data in both settings showed comparable response rates (80-82% in outpatient and 72-80% in inpatient). Improvements in the QoL were observed in both settings while costs associated with CAR-T therapy were lower in the outpatient setting. Although unplanned hospitalizations were higher in the outpatient cohort, overall HCRU was lower. Outpatient administration of CAR-T therapy appears to have comparable outcomes in safety, efficacy, and QoL to inpatient administration while reducing the economic burden.

Patient-Reported Outcomes among Multiple Myeloma Patients Treated with Standard of Care Idecabtagene Vicleucel.

Idecabtagene vicleucel (ide-cel) was the first FDA-approved chimeric antigen receptor T-cell therapy for relapsed/refractory multiple myeloma (RRMM) patients. This was the first study to evaluate patient-reported outcomes (PROs) among RRMM patients receiving ide-cel in standard of care (SOC). We prospectively assessed health-related quality of life (HRQOL) and symptoms from pre-infusion (baseline) through day (D)90 post-infusion. Baseline PRO associations with patient characteristics, mean PRO changes, and time to stable change were evaluated with t-tests, linear mixed-effects models, and Kaplan-Meier analyses, respectively. Within-person change scores and minimally important difference thresholds determined clinical and meaningful significance. Participants (n = 42) were a median of 66 years old (range: 43-81). At baseline, extramedullary disease was associated with worse physical well-being (p = 0.008), global pain (p < 0.001), performance status (p = 0.002), and overall symptom burden (p < 0.001). Fatigue (p < 0.001) and functional well-being (p = 0.003) worsened by D7 before returning to baseline levels. Overall HRQOL (p = 0.008) and physical well-being (p < 0.001) improved by D60. Most participants reported PRO improvement (10-57%) or maintenance (23-69%) by D90. The median time it took to stabile deterioration in functional well-being was 14 days. The median time it took to stabile improvement in physical and emotional well-being was 60 days. Overall, RRMM patients reported improvements or maintenance of HRQOL and symptom burden after SOC ide-cel.

Factors associated with refractoriness or early progression after idecabtagene vicleucel in patients with relapsed/refractory multiple myeloma: U.S. Myeloma Immunotherapy Consortium real world experience.

While response rates and survival outcomes have been very promising for idecabtagene vicleucel (ide-cel), a proportion of patients do not respond or relapse early after this B-cell maturation antigen (BCMA) targeted CAR T-cell therapy. Understanding the characteristics of these patients is important for patient selection and development of novel strategies to improve outcomes. We evaluated factors associated with early progression (progression or death due to myeloma ≤ 3 months after CAR T infusion) in patients treated with standard of care ide-cel at 11 US academic centers. Among 211 patients that received ide-cel, 43 patients had a progressive event ≤ 3 months of infusion. Patients with a history of extramedullary disease, prior BCMA targeted therapy, elevated ferritin at lymphodepletion, use of bridging therapy, Hispanic ethnicity, plasma cell leukemia and t(4;14) were more likely to progress ≤ 3 months of infusion (p < 0.05). Of these risk factors for early progression identified in univariate analyses, history of extramedullary disease, prior BCMA targeted therapy, elevated ferritin at lymphodepletion, plasma cell leukemia, and t(4;14) were associated with worse progression-free survival (PFS) in multivariable analysis. Presence of three or more of these factors had a significant negative impact on PFS (p < 0.001; median PFS for ≥ 3 factors, 3.2 months vs. 0 factors, 14.1 months). This study helps identify patients at high risk of early progression after CAR T who may benefit from specific interventions pre and post CAR T to improve outcomes.

Experience of Autologous Stem Cell Transplant in Multiple Myeloma: The Patient and Caregiver Perspective.

A qualitative study of the experiences of patients who received autologous stem cell transplant (ASCT) for the treatment of multiple myeloma (MM) was conducted to better understand their MM disease journey, including first symptoms, diagnosis, ASCT, and recovery. Sixteen participants, including 12 patients with MM and 4 caregivers of patients with MM, were interviewed in focus group meetings. Pain, weakness, and bone pain were common first symptoms among patients. The MM diagnosis was often made by a hematologist or oncologist. Patients were referred to a specialized oncologist after diagnosis, who was the primary driver in making ASCT treatment decisions. Eight patients received their ASCT in the inpatient setting, with some having lengthy hospital stays; 4 received their ASCT in an outpatient setting with 3 eventually being hospitalized. The focus groups identified that patients and caregivers perceived various unmet needs and impacts on quality of life throughout their transplant journey. Educational resources and innovative therapies are needed to reduce the disease burden of MM and enhance the quality of life for both patients and their caregivers.

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

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

Impact of weight and creatinine adjustments on the accuracy of Cockcroft-gault equation in hematopoietic cell transplant patients.

BACKGROUND: Hematopoietic cell transplant (HCT) patients undergo pre- transplant renal function evaluation to confirm transplant eligibility and tailor pharmacotherapy. There is limited evidence regarding the most accurate method of estimating creatinine clearance (CrCl) within this patient population and no studies exist that evaluate the weight utilized within the Cockcroft-Gault (CG) equation in HCT patients. This study evaluates different weight and serum creatinine (SCr) adjustments utilized within the CG equation estimating for renal clearance in patients undergoing HCT. OBJECTIVE: This is a retrospective, single center analysis of adult HCT patients who underwent pre-transplant evaluation with a measured CrCl using a 24-h urine creatinine collection. The primary outcome was to evaluate the correlation of various weights used in estimation of CrCl compared to measured CrCl. Key secondary outcomes include evaluation of the impact of various weights on estimated CrCl in subpopulations, evaluation of adjusting SCr to pre-determined limits, and determination of an appropriate obesity threshold to utilize body weight adjustments. RESULTS: Seven-hundred and forty-two patients were included in the study. In the primary analysis, CG utilizing adjusted body weight (ADjBW0.4 ) had a greater correlation (r = .812) to measured CrCl when compared to total or ideal body weight (r = .801 and r = .790 respectively). The threshold of 120% of ideal body weight (IBW) produced less bias and greater accuracy in comparison to the threshold of 140% IBW. In patients 60 years or older, rounding low SCr values up .8 or 1 mg/dL resulted in decreased correlation and a greater mean difference in comparison to not rounding SCr. CONCLUSION: In HCT patients who are overweight or obese, ADjBW .4 is the most accurate weight for the CG equation. In HCT patients who have a total body weight < 120% IBW, total body weight is the most accurate weight to utilize. Rounding up low SCr to .8 or 1 mg/dL does not improve the accuracy or led to less bias of the CG equation.

The CAR-HEMATOTOX score as a prognostic model of toxicity and response in patients receiving BCMA-directed CAR-T for relapsed/refractory multiple myeloma.

BACKGROUND: BCMA-directed CAR T-cell therapy (CAR-T) has altered the treatment landscape of relapsed/refractory (r/r) multiple myeloma, but is hampered by unique side effects that can lengthen hospital stays and increase morbidity. Hematological toxicity (e.g. profound and prolonged cytopenias) represents the most common grade ≥ 3 toxicity and can predispose for severe infectious complications. Here, we examined the utility of the CAR-HEMATOTOX (HT) score to predict toxicity and survival outcomes in patients receiving standard-of-care idecabtagene vicleucel and ciltacabtagene autoleucel. METHODS: Data were retrospectively collected from 113 r/r multiple myeloma patients treated between April 2021 and July 2022 across six international CAR-T centers. The HT score-composed of factors related to hematopoietic reserve and baseline inflammatory state-was determined prior to lymphodepleting chemotherapy. RESULTS: At lymphodepletion, 63 patients were HTlow (score 0-1) and 50 patients were HThigh (score ≥ 2). Compared to their HTlow counterparts, HThigh patients displayed prolonged severe neutropenia (median 9 vs. 3 days, p < 0.001), an increased severe infection rate (40% vs. 5%, p < 0.001), and more severe ICANS (grade ≥ 3: 16% vs. 0%, p < 0.001). One-year non-relapse mortality was higher in the HThigh group (13% vs. 2%, p = 0.019) and was predominantly attributable to fatal infections. Response rates according to IMWG criteria were higher in HTlow patients (≥ VGPR: 70% vs. 44%, p = 0.01). Conversely, HThigh patients exhibited inferior progression-free (median 5 vs. 15 months, p < 0.001) and overall survival (median 10.5 months vs. not reached, p < 0.001). CONCLUSIONS: These data highlight the prognostic utility of the CAR-HEMATOTOX score for both toxicity and treatment response in multiple myeloma patients receiving BCMA-directed CAR-T. The score may guide toxicity management (e.g. anti-infective prophylaxis, early G-CSF, stem cell boost) and help to identify suitable CAR-T candidates.

Cardiac events after standard of care idecabtagene vicleucel for relapsed and refractory multiple myeloma.

Idecabtagene vicleucel (ide-cel) is a type of B-cell maturation antigen (BCMA)-targeting chimeric antigen receptor T-cell (CAR-T) approved for the treatment of relapsed and refractory multiple myeloma (RRMM). Currently, the incidence of cardiac events associated with ide-cel remains unclear. This was a retrospective single-center observational study of patients treated with ide-cel for RRMM. We included all consecutive patients who received standard-of-care ide-cel treatment at least 1-month follow-up. Baseline clinical risk factors, safety profile, and responses were examined based on the development of a cardiac event. A total of 78 patients were treated with ide-cel, and 11 patients (14.1%) developed cardiac events: heart failure (5.1%), atrial fibrillation (10.3%), nonsustained ventricular tachycardia (3.8%), and cardiovascular death (1.3%). Only 11 of the 78 patients had repeat echocardiogram. Baseline risk factors associated with the development of cardiac events included being female sex and having poor performance status, λ light-chain disease, and advanced Revised International Staging System stage. Baseline cardiac characteristics were not associated with cardiac events. During index hospitalization after CAR-T, higher-grade (≥grade 2) cytokine release syndrome (CRS) and immune cell-associated neurologic syndrome were associated with cardiac events. In multivariable analyses, the hazard ratio for the association of the presence of cardiac events with overall survival (OS) was 2.66 and progression-free survival (PFS) was 1.98. Ide-cel CAR-T for RRMM was associated with similar cardiac events as other types of CAR-T. Worse baseline performance status and higher-grade CRS and neurotoxicity were associated with cardiac events after BCMA-directed CAR-T-cell therapy. Our results suggest that the presence of cardiac events may confer worse PFS or OS; although because of the small sample size, the power to detect an association was limited.

Idecabtagene Vicleucel for Relapsed/Refractory Multiple Myeloma: Real-World Experience From the Myeloma CAR T Consortium.

PURPOSE: Idecabtagene vicleucel (ide-cel) is an autologous B-cell maturation antigen-directed chimeric antigen receptor T-cell therapy approved for relapsed/refractory multiple myeloma (RRMM) on the basis of the phase II pivotal KarMMa trial, which demonstrated best overall and ≥ complete response rates of 73% and 33%, respectively. We report clinical outcomes with standard-of-care (SOC) ide-cel under the commercial Food and Drug Administration label. METHODS: Data were retrospectively collected from patients with RRMM who underwent leukapheresis as of February 28, 2022, at 11 US institutions with intent to receive SOC ide-cel. Toxicities were graded per American Society for Transplantation and Cellular Therapy guidelines and managed according to each institution's policies. Responses were graded on the basis of the International Myeloma Working Group response criteria. RESULTS: One hundred fifty-nine of 196 leukapheresed patients received ide-cel by data cutoff. One hundred twenty (75%) infused patients would have been ineligible for participation in the KarMMa clinical trial because of comorbidities at the time of leukapheresis. Any grade and grade ≥ 3 cytokine release syndrome and neurotoxicity occurred in 82/3% and 18/6%, respectively. Best overall and ≥ complete response rates were 84% and 42%, respectively. At a median follow-up of 6.1 months from chimeric antigen receptor T infusion, the median progression-free survival was 8.5 months (95% CI, 6.5 to not reached) and the median overall survival was 12.5 months (95% CI, 11.3 to not reached). Patients with previous exposure to B-cell maturation antigen-targeted therapy, high-risk cytogenetics, Eastern Cooperative Oncology Group performance status ≥ 2 at lymphodepletion, and younger age had inferior progression-free survival on multivariable analysis. CONCLUSION: The safety and efficacy of ide-cel in patients with RRMM in the SOC setting were comparable with those in the phase II pivotal KarMMa trial despite most patients (75%) not meeting trial eligibility criteria.

Efficacy and safety of selinexor-based regimens for relapsed/refractory multiple myeloma: a systematic review of literature.

With the incorporation of novel agents in earlier lines of therapy, an increasing number of multiple myeloma patients are refractory to traditional classes of drugs. Selinexor in combination with dexamethasone has emerged as a viable option for heavily pretreated triple-class relapsed and refractory multiple myeloma (RRMM). In this systematic review, we analyzed available literature on the role of selinexor in RRMM. The Boston trial demonstrated that selinexor when combined with dexamethasone and bortezomib is associated with a better depth and duration of response without excessive toxicity, compared with bortezomib and dexamethasone alone. Similarly, selinexor in combination with carfilzomib and dexamethasone was found to have a durable response and tolerable safety profile in both carfilzomib-naive and carfilzomib refractory RRMM patients. Selinexor in combination with IMiDs (lenalidomide and pomalidomide) as well as CD38 monoclonal antibodies (daratumumab) also have promising results. Selinexor combination therapy is both safe and effective for patients with pretreated RRMM.

Early cytopenias and infections after standard of care idecabtagene vicleucel in relapsed or refractory multiple myeloma.

Idecabtagene vicleucel (ide-cel) was FDA-approved in March 2021 for the treatment of relapsed/refractory multiple myeloma after 4 lines of therapy. On the KarMMa trial, grade ≥ 3 cytopenias and infections were common. We sought to characterize cytopenias and infections within 100 days after ide-cel in the standard-of-care (SOC) setting. This multi-center retrospective study included 52 patients who received SOC ide-cel; 47 reached day-90 follow-up. Data were censored at day 100. Grade ≥ 3 cytopenia was present among 65% of patients at day 30 and 40% of patients at day 90. Granulocyte colony stimulating factor (G-CSF) was administered to 88%, packed red blood cell transfusions to 63%, platelet transfusions to 42%, thrombopoietin (TPO) agonists to 21%, intravenous immunoglobulin to 13%, and CD34+ stem cell boosts to 8%. At day 100, 19% and 13% of patients had ongoing use of TPO agonists and G-CSF, respectively. Infections occurred in 54% of patients and were grade ≥ 3 in 23%. Earlier infections in the first 30 days were typically bacterial (68%) and severe (50%). Later infections between days 31 and 100 were 50% bacterial and 42% viral; only 13% were grade ≥ 3. On univariate analysis, high pre-CAR-T marrow myeloma burden (≥ 50%), circulating plasma cells at pre-lymphodepletion (LD), and grade ≥ 3 anemia at pre-LD were associated with grade ≥ 3 cytopenia at both days 30 and 90. Longer time from last bridging treatment to LD was the only significant risk factor for infection.

Longitudinal Collection of Patient-Reported Outcomes and Activity Data during CAR-T Therapy: Feasibility, Acceptability, and Data Visualization.

Background: Clinicians must closely monitor patients for toxicities after chimeric antigen receptor T-cell therapy (CAR-T). Patient-reported outcomes (PROs) (e.g., toxicities, quality of life) and activity data (e.g., steps, sleep) may complement clinicians' observations. This study tested the feasibility and acceptability of collecting PROs and activity data from patients with hematologic malignancies during CAR-T and explored preliminary data patterns. Methods: Participants wore a Fitbit tracker and completed PROs at several timepoints through 90-days post-infusion. Feasibility was assessed with a priori benchmarks for recruitment (≥50%), retention (≥70%), PRO completion (≥70%), and days wearing the Fitbit (≥50%). Acceptability was assessed with participant satisfaction (a priori benchmark > 2 on a 0−4 scale). Results: Participants (N = 12) were M = 66 years old (SD = 7). Rates of recruitment (68%), retention (83%), PRO completion (85%), and days wearing the Fitbit (85%) indicated feasibility. Satisfaction with completing the PROs (M = 3.2, SD = 0.5) and wearing the Fitbit (M = 2.9, SD = 0.5) indicated acceptability. Preliminary data patterns suggested that participants with better treatment response (vs. progressive disease) had a higher toxicity burden. Conclusions: Longitudinal PRO and activity data collection was feasible and acceptable. Data collected on a larger scale may be used to specify risk prediction models to identify predictors of severe CAR-T-related toxicities and inform early interventions.