Hilal, Talal

Background: Follicular dendritic cell sarcoma (FDCS) is a rare low- to intermediate-grade sarcoma, typically presenting as a slowly growing, painless mass composed of spindle-shaped cells in a whorled pattern. First described in 1986, FDCS has since been identified in several hundred cases. FDCS originates from mesenchymal dendritic cells and is distinct from other histiocytic neoplasms. Its management aligns more with soft tissue sarcomas. Epidemiologically, FDCS is exceedingly rare, constituting less than 0.4% of soft tissue sarcomas. Methods: With IRB approval, we identified patients with biopsy-proven FDCS treated at Mayo Clinic. Chart review extracted clinical characteristics, laboratory testing, treatment data, and clinical outcomes, compiled into Excel. Data analysis was performed through RStudios. Descriptive statistics of patient characteristics, such as gender and stage of disease, were summarized in tables. We compared overall survival (OS) through Kaplan Meier curves, stratifying patients into cohorts based on topics of interest, such as differences in survival in nodal vs. extranodal disease or differences in survival among different chemotherapy regimens. Results: Forty patients met the inclusion criteria, of biopsy proved FCDS. Median age at diagnosis was 57.7 years (SD 14). Men comprised 45% of patients. Locations of malignancy were abdomen and pelvis (32.5%), thoracic and pulmonary regions (32.5%), lymph nodes and neck (20.0%), musculoskeletal (2.5%), and other locations (12.5%). Primary therapies included surgical resection (42.5%), systemic chemotherapy (32.5%), no treatment (10.0%), radiation (2.5%), with data missing for 12.5% of cases. Concurrent or preceding Castleman's Disease was seen in 7.5% (3/40) of patients; one case preceded FCDS, and two were concurrent. Of these patients with Castleman's Disease, one was resected and the other two were not. Two cases were unicentric, and one was multicentric. First-line systemic chemotherapy was most often gemcitabine and docetaxel, with 9/40 patients receiving this regimen. Ifosfamide and doxorubicin were utilized in 3/40 patients. 2/4 patients had received doxorubicin alone. 2/4 patients had received CHOP. The response rate for patients with gemcitabine and docetaxel was complete response for 2/9 (22%) patients, partial response for 2/9 (22%), stable disease for 2/9 (22%), progressive disease for 1/9 (11%), and missing for 2/9 (22%), giving an overall response rate of 67%. For ifosfamide and doxorubicin, one patient had partial response (33%), another had stable disease (33%), and the last patient's data was missing (33%), adding up to a 66% overall response rate. For CHOP, one patient had progressive disease, and the other had partial response. For doxorubicin, both patients had stable disease. At a median follow-up of 29.5 months (IQR 9.2-75.2 months), the median OS was 160.68 months for the group with both nodal and extranodal disease versus 39.95 months for the extranodal disease-only group. The median OS of the nodal disease alone was not reached, with an estimated 2-year OS of 75%. To evaluate the impact of various primary therapies on outcomes in patients with advanced disease, we conducted a survival analysis by therapy used (no treatment, radiation, surgical resection, and systemic chemotherapy). Patients receiving no treatment had a median survival time of 28.9 months, while those treated with radiation had a median survival time of 19.3 months. Patients undergoing surgical resection had an undetermined median survival time, but notably, 80% were alive at the end of the time period analyzed in this study with a median follow-up time of 60.7 months. Those receiving systemic chemotherapy had a median survival time of 30.7 months. Conclusions: This project is one of the largest known single-center studies dedicated to FDCS. We show that the incidence of preceding or concurrent Castleman's Disease is relatively low. Gemcitabine and docetaxel was the most utilized chemotherapy regimen, but there weren't enough data to conclude if this regimen had a better response rate compared to others. Surgical resection of advanced disease is associated with superior outcomes. When systemic therapy is needed, the median survival was lower.

PURPOSE On the basis of the results of the ZUMA-3 trial, brexucabtagene autoleucel (brexu-cel), a CD19-directed chimeric antigen receptor T-cell therapy, gained US Food and Drug Administration approval in October 2021 for adults with relapsed/refractory (R/R) B-cell ALL (B-ALL). We report outcomes of patients treated with brexu-cel as a standard therapy. METHODS We developed a collaboration across 31 US centers to study adults with B-ALL who received brexu-cel outside the context of a clinical trial. Data were collected retrospectively from October 2021 to October 2023. Toxicities were graded per American Society for Transplantation and Cellular Therapy guidelines for cytokine release syndrome (CRS) and immune effector cell–associated neurotoxicity syndrome (ICANS). RESULTS At the time of data lock, 204 patients had undergone apheresis and 189 were infused. Median follow-up time was 11.4 months. Forty-two percent of patients received brexu-cel in morphologic remission and would have been ineligible for participation in ZUMA-3. After brexu-cel, 151 achieved complete remission (CR), of which 79% were measurable residual disease (MRD) negative remissions. Median progression-free survival (PFS) was 9.5 months and median overall survival was not reached. Grade 3-4 CRS or ICANS occurred in 11% and 31%, respectively. In multivariable analysis, patients receiving consolidative hematopoietic cell transplantation (HCT; hazard ratio, 0.34 [95% CI, 0.14 to 0.85]) after brexu-cel had superior PFS compared with those who did not receive any consolidation or maintenance therapy. CONCLUSION Similar to ZUMA-3, high rates of MRD-negative CR were observed after brexu-cel treatment for R/R B-ALL. The use of HCT as consolidation after brexu-cel resulted in improved PFS.

Abstract The effect of prior inotuzumab ozogamicin (InO) treatment on brexucabtagene autoleucel (brexu-cel) outcomes remains unclear in adults with acute lymphoblastic leukemia (ALL). We conducted a retrospective multicenter analysis of 189 patients with relapsed/refractory ALL treated with brexu-cel. Over half of the patients received InO before brexu-cel (InO exposed). InO-exposed patients were more heavily pretreated (P = .02) and frequently had active marrow disease before apheresis (P = .03). Response rate and toxicity profile after brexu-cel were comparable for InO-exposed and InO-naïve patients; however, consolidation therapy after brexu-cel response was used at a higher rate in InO-naïve patients (P = .005). With a median follow-up of 11.4 months, InO-exposed patients had inferior progression-free survival (PFS; P = .013) and overall survival (OS; P = .006) in univariate analyses; however, prior InO exposure did not influence PFS (hazard ratio, 1.20; 95% confidence interval, 0.71-2.03) in multivariate models. Within InO-exposed patients, InO responders had superior PFS (P = .002) and OS (P < .0001) relative to InO-refractory patients. The timing of administering InO did not affect brexu-cel outcomes, with comparable PFS (P = .51) and OS (P = .86) for patients receiving InO as bridging therapy or before apheresis. In conclusion, although InO exposure was associated with inferior survival outcomes after brexu-cel in unadjusted analyses, these associations were no longer significant in multivariate analyses, suggesting it is unlikely that InO negatively affects brexu-cel efficacy. Our data instead imply that InO-exposed recipients of brexu-cel tend to be higher-risk patients with intrinsic adverse leukemia biology.

Abstract Background This study examines patients’ understanding of health insurance terms and concepts and quantifies health insurance literacy (HIL) levels by key sociodemographic factors. Methods This study included 393 adult patients with cancer (>18 years old) receiving treatment in two ambulatory infusion centers: Mayo Clinic in Phoenix, Arizona and the University of Mississippi Medical Center in Jackson, Mississippi. Respondents’ perceptions of their HIL were assessed using the Health Insurance Literacy Measure (HILM), a validated 21‐item measure of a consumer's ability to select and use health insurance (HIL self‐efficacy). Respondents’ knowledge of health insurance concepts (HIL knowledge) was measured using 10 items created by the Kaiser Family Foundation. The number of correct answers was categorized into three levels: 0–4 (low knowledge), 5–6 (moderate knowledge), and 7–10 (high knowledge). Multivariable logistic regressions were used to compare correct answers to HIL knowledge questions by HIL self‐efficacy. Results Nearly three‐quarters of patients had high HIL self‐efficacy and high HIL knowledge (70.5%), understanding basic insurance terms, such as premiums and deductibles. Relatively low percentages of patients correctly answered questions about the meaning of provider networks, health insurance formularies, and calculating out‐of‐pocket spending in scenarios when insurers pay a portion of allowed charges. Lower HIL knowledge was more common among patients with less educational attainment (<college: 15.2%; ≥college: 4.7%), lower household income (<$4999: 11.8%; ≥$5000: 6.1%), and low HIL self‐efficacy scores (low: 24.8%; high: 5.2) (all p values <.05). Conclusions Efforts to improve HIL and navigation of health insurance plan features are required, especially for socioeconomically vulnerable patients.

ImportanceMeasurable residual disease (MRD) refers to the presence of disease at low levels not detected by conventional pathologic analysis. The association of MRD status as a surrogate end point of clinical outcome in chronic lymphocytic leukemia (CLL) has not been established in the era of targeted agents. Assessing the association of MRD with progression-free survival (PFS) may improve its role as a surrogate marker and allow its use to accelerate drug development.ObjectiveTo assess the association between MRD and PFS in CLL using data from prospective clinical trials that studied targeted agents or obinutuzumab-based treatment.Data SourcesClinical studies on CLL were identified via searches of PubMed, Embase, Scopus, and Web of Science from inception through July 31, 2023.Study SelectionProspective, single-arm, and randomized clinical trials that assessed targeted agents or obinutuzumab-based treatment and reported PFS by MRD status were included. Studies with insufficient description of MRD information were excluded.Data Extraction and SynthesisStudy sample size, median patient age, median follow-up time, line of treatment, MRD detection method and time points, and survival outcomes were extracted.Main Outcomes and MeasuresAnalyses of survival probabilities and hazard ratios (HRs) were conducted for PFS according to MRD status. Meta-analyses were performed using a random-effects model.ResultsA total of 11 prospective clinical trials (9 randomized and 2 nonrandomized) including 2765 patients were analyzed. Achieving undetectable MRD (uMRD) at 0.01% was associated with an HR of 0.28 (95% CI, 0.20-0.39; P &amp;lt; .001) for PFS. Median PFS was not reached in both groups (uMRD vs MRD), but the estimated 24-month PFS was better in the uMRD group (91.9% [95% CI, 88.8%-95.2%] vs 75.3% [95% CI, 64.7%-87.6%]; P &amp;lt; .001). The association of uMRD with PFS was observed in subgroup analyses in the first-line treatment setting (HR, 0.24; 95% CI, 0.18-0.33), relapsed or refractory disease setting (HR, 0.34; 95% CI, 0.16-0.71), and trials using time-limited therapy (HR, 0.28; 95% CI, 0.19-0.40).Conclusions and RelevanceThe findings of this systematic review and meta-analysis suggest that assessing MRD status as an end point in clinical trials and as a surrogate of PFS may improve trial efficiency and potentially allow for accelerated drug registration.

Abstract T-cell/histiocyte–rich large B-cell lymphoma (THRLBCL) is a rare histologic variant of LBCL. Limited data regarding CD19–directed chimeric antigen receptor T-cell (CART) therapy in relapsed/refractory (R/R) THRLBCL suggest poor efficacy. We investigated CART outcomes for R/R THRLBCL through the Center for International Blood and Marrow Transplant Research registry. A total of 58 adult patients with R/R THRLBCL who received commercial CD19-CART therapy between 2018 and 2022 were identified. Most patients (67%) had early relapse of disease (45% primary refractory) with a median of 3 (range, 1-7) prior therapies and were treated with axicabtagene ciloleucel (69%). At median follow-up of 23 months after CART therapy, 2-year overall and progression-free survival were 42% (95% confidence interval [CI], 27-57) and 29% (95% CI, 17-43), respectively. In univariable analysis, poor performance status before CART therapy was associated with higher mortality (hazard ratio, 2.35; 95%CI, 1.02-5.5). The 2-year cumulative incidences of relapse/progression and nonrelapse mortality were 69% and 2%, respectively. Grade ≥3 cytokine release syndrome and immune effector cell–associated neurologic syndrome occurred in 7% and 15% of patients, respectively. In this largest analysis of CD19-CART therapy for R/R THRLBCL, ∼30% of patients were alive and progression free 2 years after CART therapy. Despite a high incidence of progression (69% at 2 years), these results suggest a subset of patients with R/R THRLBCL may have durable responses with CARTs.

e19008 Background: Bispecific antibodies (BsAb) have emerged as a new treatment modality for relapsed/refractory non-Hodgkin lymphomas (R/R NHL). They exert their effect by binding to CD3 on T-cells and CD19 or CD20 on lymphoma cells, activating the T-cell to exert cytotoxic effects against the tumor and normal B-cells. Treatment related adverse events (TRAE) include infections, cytokine release syndrome (CRS), neurotoxicity (ICANS). This meta-analysis was conducted to assess prevalence of TRAEs from prospective clinical trials that evaluated BsAb in R/R NHL. Methods: A systematic review was conducted through PubMed, Embase, Scopus, Web of Science, and Cochrane to identify BsAb clinical trials in NHL through October 2023. Eligible studies included phase I-III trials evaluating BsAb in any type of NHL, either as monotherapy or combination therapy irrespective of prior lines of treatment. Primary outcomes of interest include infection, neutropenia, CRS, and ICANS. All studies were weighted equally. Pooled prevalence estimates of TRAE were calculated using common and random effects models. Heterogeneity tests were performed using Cochran’s Q test. Subgroup analysis examined infection rates in monotherapy versus combination therapy cohorts. Results: After screening 1039 studies, 36 clinical trials with 2162 patients were included. The lymphoma subtypes were diffuse-large B cell lymphoma, follicular lymphoma, and mantle cell lymphoma. The BsAbs included mosunetuzumab (13 studies), epcoritamab (10 studies), blinatumomab (5 studies), glofitamab (5 studies), odronextamab (2 studies), and AFM11 (1 study). The median age of patients was 66 years, and patients had received a median of two prior lines of therapy. Median follow-up duration was 9.1 months. The prevalence of all-grade infections was 35% (95% CI: 0.33-0.38; I2 = 79%). For grade ≥3 infections, the prevalence was 16% (95% CI: 0.14-0.18, (I2 = 77%). There were higher rates of all-grade infections in the combination therapy cohort (41%, 95% CI: 0.36-0.47) compared with the monotherapy cohort (33%, 95% CI: 0.30-0.36). All-grade and grade ≥3 neutropenia occurred in 31% (95% CI: 0.29-0.34; I2 = 80%) and 22% (95% CI: 0.20-0.24, I2 = 61%) of patients. CRS was observed in 45% of patients (95% CI: 0.43-0.48, I2 = 85%). Grade ≥3 CRS occurred in only 2% of patients (95% CI: 0.02-0.03, I2 = 0%, p = 0.99). ICANS occurred in 12% (95% CI: 0.10-0.14, I2 = 90%) while grade ≥3 ICANS was rare, at 3% (95% CI: 0.02-0.03, I2 = 0%, p = 0.99). Conclusions: BsAb is associated with nontrivial rates of infections and neutropenia. The rates of high grade CRS and ICANS are low. The heterogeneity of the findings could be attributed by an underreporting of TRAE and small sample sizes from various studies. These results highlight the need for vigilant practices to diagnose and treat infections early and consideration for antibacterial prophylaxis in this immunocompromised population.

11030 Background: Drug regulators operate on their own timelines to assess the safety and efficacy of new drugs and/or extensions to existing indications, such that there are delays between regulators. During such a gap, patients in the “early” domain have access to the approved drug, while those in the “late” domain do not, outside of compassionate use. Our study aimed to quantify the “opportunity lost” for new therapies approved by FDA and EMA, assuming patients in the late domain receive standard-of-care (SOC) therapy – which is presumably inferior to the new drug – during the gap. Methods: Anticancer drugs approved by both FDA and EMA were identified through the HemOnc knowledgebase. Inclusion criteria included: 1) drugs approved in both domains based on the same randomized clinical trial (RCTs) for the same indication; 2) a primary time-to-event endpoint; and 3) a quantitated median time-to-event for the primary endpoint. For each included trial, the approval gap between FDA and EMA in days and the ratio of approval gap to median control arm time-to-event duration was calculated. A ratio ≥2 implies that, on average, no late domain patients starting treatment in the first half of the gap would be expected to have access to the new drug prior to an event. Results: Of 60 eligible RCTs, 59 had calculable median event durations. 25 (42%) had a primary overall survival endpoint; the most common surrogate endpoint was progression-free survival (PFS; 29/59; 49%). The median (interquartile range [IQR]) approval gap was 186 (124-271) days, with FDA being the first approver in 56/59 (95%) cases. The median (IQR) ratio of approval gap to median control arm event duration was 0.63 (0.35-1.11). Drugs with ratio ≥2 (Table) were targeted or immunotherapies; 7/8 (88%) were approved with PFS endpoint; 5/8 (62.5%) were approved for second line or later. Conclusions: Our study shows that FDA approves most drugs prior to EMA and a nontrivial number of patients may experience progression or death events while awaiting access to anticancer therapies already approved in another domain. The analysis does not take into consideration scenarios in which the new therapy is inferior to SOC or delays in patient access (due to slow uptake; regulatory barriers [in Europe/UK]; or patient affordability [in US]). Further regulatory collaboration (e.g., Project Orbis) between FDA and EMA could help to reduce and potentially ameliorate this differential in access to new cancer drugs in the future. [Table: see text]

11023 Background: Randomized clinical trials (RCTs) in cancer typically compare experimental to control arm regimens. The choice of an appropriate control (ctrl) arm can have a major impact on the expected success of an RCT. The frequency with which cancer RCTs use control arms based on established dosing and scheduling protocols has not been described. Methods: The HemOnc knowledgebase (KB) was used to identify systemic anti-cancer therapy (SACT) regimen variants, defined as regimens with identical components that differ in dosing, scheduling, and/or route. Non-cancer, nonrandomized, and non-SACT studies were excluded. Study publication year was used to define standard variants as those evaluated in the experimental arm of a positive phase 3 RCT >1 year prior to publication as a control arm, regardless of cancer type or context of treatment. Study-variant dyads were evaluated to determine whether the variant was standard. Success rates of RCTs with standard vs non-standard control arms were evaluated with Fisher’s exact test. Results: 5221 studies were associated with ≥1 named variant in the HemOnc KB, as of 2024-02-06. After exclusions, there were 3511 study-variant dyads (2386 studies; 1714 variants). The 9 most common regimens are shown in the Table. The median (IQR) number of variants per regimen was 2 (1-3); carboplatin & paclitaxel (CP) had the most variants (n=33). Across all control arm study-variant dyads, 2228/3492 (64%) utilized non-standard variants. For example, 60/97 studies (62%) of docetaxel as control used the 75 mg/m2 q3wk variant after it was established in 2000, whereas n=27 others used 19 non-standard variants. Trials that used a standard control arm had a numerically higher success rate, 45% vs 42% (OR 1.10, 95% CI 0.92-1.32). Conclusions: Non-standard regimen variants are frequently used in cancer RCTs. Reasons for this could include toxicity, patient convenience, or emerging data from smaller studies that establish comparable efficacy or improved toxicity to standard variants. However, the a priori efficacy of non-standard control arms is less rigorously established, and trials with standard control arms might be more successful. Future directions include quantifying the granular differences between standard and non-standard variants and investigating whether certain types of non-standard variation (e.g. fewer cycles, lower doses) associate with trial success rates. [Table: see text]

Abstract Introduction: Chimeric antigen receptor T-cell (CAR-T) therapy is an established treatment modality for the management of refractory and/or relapsed non-Hodgkin lymphoma (NHL). Despite restrictions on granulocyte colony-stimulating factor (G-CSF) use in registration clinical trials due to potential worsening of cytokine release syndrome (CRS), G-CSF is often prescribed for neutrophil recovery post-CAR-T in clinical practice. We conducted a retrospective study to assess the association between G-CSF use and the safety and efficacy of CAR-T. Methods: Following Institutional Review Board approval, we retrospectively analyzed NHL patients receiving commercial CD19-targeted CAR-T across Mayo Clinic sites (Arizona, Florida, and Minnesota) between October 2017 and May 2023. Demographics, labs, and post CAR-T events were collected. Electronic medical records were reviewed for G-CSF exposure within Day 1 - 100 post-CAR T. Differences by G-CSF status were examined using a Chi-square test and Kruskal Wallis tests. Hazard ratios (HR) and 95% confidence intervals (CI) for overall survival (OS) were calculated using Cox model. Results: Among 270 CAR-T patients; 106 received G-CSF within 30 days and 164 did not. Median age was 56.9 with G-CSF and 58.3 without G-CSF. Most were male (75.2% G-CSF, 62.6% no G-CSF). Diffuse large B cell lymphoma was the predominant NHL subtype (67.0% G-CSF, 65.2% no G-CSF). G-CSF within 30 days was not associated with reduced incidence of neutropenic fever (11.7% G-CSF vs 9.9% no G-CSF, p = 0.6593) or documented infection (22.1% vs 18.3%, p = 0.4439). G-CSF correlated with decreased profound neutropenia duration (ANC &lt; 100 μL, 0 vs 2 days, p &lt; 0.0001) and incidence within 30 days ( 31.7% vs 60.4%, p &lt; 0.0001) as well as incidence of protracted profound neutropenia (&gt; 7 days, 3.8% vs 22.8%, p &lt; 0.0001). G-CSF was associated with a higher incidence of cytopenias between days 30 -100: severe neutropenia (ANC &lt; 500/uL, 28.8% vs 15.2%, p = 0.0075), severe anemia (Hb &lt; 8 g/dL, 21% vs 9.7%, p = 0.0114), and severe thrombocytopenia (Plt &lt; 50 g/L, 35.2% vs 20.9%, p = 0.0099). Logistic regression analysis showed that none of the examined covariates, including prior autologous stem cell transplant, ECOG PS score, and receipt of bridging therapy, were associated with severe neutropenia likelihood. G-CSF was associated with a higher CRS incidence (89.6% vs 79.9%, p = 0.0343), but grade 3 CRS or higher (4.7% vs 3.7%, p = 0.6675) was no different. No difference in complete response rates (66% vs 61.1%, p = 0.4707) or 2-year OS (p = 0.523) was observed between the 2 groups. Conclusion: G-CSF within 30 days was associated with reduced duration and incidence of profound neutropenia without a significant impact on incidence of neutropenic fever or documented infections. There was a signal of association between G-CSF and increased incidence of low-grade CRS and delayed cytopenias (day 30-100) that warrants confirmation in larger studies. Citation Format: Lay She Ng, Claire I. Yee, Radhika Bansal, Mohamed A. Kharfan-Dabaja, Grzegorz S. Nowakowski, Allison C. Rosenthal, Javier Munoz, Januario Castro, Wern Lynn Ng, Hemant S. Murthy, Yi Lin, Matthew R. Buras, Madiha Iqbal, Yucai Wang, Talal Hilal. Impact of G-CSF on safety and efficacy of CAR T-cell therapy in non-Hodgkin lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6327.