Citations

Background: Reduced left atrial (LA) compliance (LAC) contributes to pulmonary venous hypertension in heart failure with preserved ejection fraction (HFpEF); however the underlying mechanisms are poorly defined. We hypothesized that microvascular inflammation with rarefaction and impaired nitric oxide (NO) signaling, LA titin hypophosphorylation and fibrosis may each contribute to reduced LAC in HFpEF. Methods: Invasive LA pressure-volume (PV) analyses (open-chest; pericardiotomy; admittance catheter) were performed in 9 aged dogs with experimental hypertension (bilateral renal wrap + DOCA; HFpEF) compared to 13 sham-operated young adult dogs (control). LAC was measured at end-LA reservoir during acute preload reduction (cava occlusion). LA tissue and LA microvascular function were analyzed. Results: Compared to controls, the curvilinear end-LA reservoir PV relationship ( Fig A ) was shifted upward/leftward in HFpEF (LA diastolic stiffness constant 0.08 vs 0.16 mmHg/mL in controls, p=0.005). LA microvascular density (MVD; CD31 stain) tended to be lower in HFpEF than controls (2154±578 vs 2650±523 vessels/mm 2 , p=0.07) and LA MVD negatively correlated with the LA diastolic stiffness constant (r=-0.66, p=0.006). LA microvessels from HFpEF dogs showed impaired endothelium-dependent shear stress-mediated dilation compared to controls, consistent with impaired NO signaling ( Fig B ). Titin isoform expression was similar between groups, but isoform N2B (stiffer) was (p=0.03) and N2BA (compliant) tended to be (p=0.09) hypophosphorylated in HFpEF LA appendage (LAA) tissue. Fibrosis (Picrosirius Red) was similar between groups in the LA free wall and LAA, but increased in areas adjacent to the pulmonary veins in HFpEF (27±12% vs controls 15±8%, p=0.01). Conclusion: In experimental HFpEF, LAC was reduced in association with evidence of LA microvascular rarefaction and impaired NO signaling, titin hypophosphorylation and regional increases in LA fibrosis.

Background: Insulin-like growth factor binding protein7 (IGFBP-7) and tissue inhibitor of metalloproteinase-2 (TIMP-2) reflect G1-cell cycle arrest and are used as biomarkers for AKI. Recent studies show that these biomarkers rise in ischemic conditions and suggest that they actually may limit the severity of AKI. We tested the hypothesis that renal vein [IGFBP-7]*[TIMP-2] correlate with reductions in renal blood flow (RBF) and post-stent single kidney (SK)-GFR changes in patients with RVD undergoing contrast-based imaging and stent revascularization Methods: Inpatient studies were performed during 150 mEq Na+ intake and ACE/ARB Rx in patients with hemodynamically severe RVD (n=29, Doppler velocity = 318 ± 100cm/sec, and eGFR= 34.7 ± 11.7 mL/ min) scheduled for renal artery stenting, and compared to essential hypertensive (EH) healthy controls (n=32). Cortical and medullary RBFs (by multidetector CT) and renal vein levels of IGFBP-7 and TIMP-2 were measured before renal artery stenting and 3 months later Results: Pre-stenting IGFBP-7 and TIMP-2 levels were elevated in RVD compared to EH (18.5±2. vs 15.7±1.5 and 97.4±23.1vs 62.7±9.2 ng/mL respectively, P <0.0001). Baseline renal vein levels of IGFBP-7 * TIMP-2 correlated inversely with pre-stent RBF (r= - 0.53, P=0.01) and directly with the change (%) in SK-GFR observed 3 months after stenting Conclusion: IGFBP-7 and TIMP-2 levels are elevated in patients with chronic RVD as a function of the baseline reduction in RBF, and associate with subsequent improvement in SK-GFR 3 months after revascularization. These data are consistent with renovascular occlusion inducing cell-cycle arrest that serves to protect kidney function.

Real-time RT-PCR is considered the gold standard confirmatory test for coronavirus disease 2019 (COVID-19). However, many scientists disagree, and it is essential to understand that several factors and variables can cause a false-negative test. In this context, cycle threshold (Ct) values are being utilized to diagnose or predict SARS-CoV-2 infection. This practice has a significant clinical utility as Ct values can be correlated with the viral load. In addition, Ct values have a strong correlation with multiple haematological and biochemical markers. However, it is essential to consider that Ct values might be affected by pre-analytic, analytic, and post-analytical variables such as collection technique, specimen type, sampling time, viral kinetics, transport and storage conditions, nucleic acid extraction, viral RNA load, primer designing, real-time PCR efficiency, and Ct value determination method. Therefore, understanding the interpretation of Ct values and other influential factors could play a crucial role in interpreting viral load and disease severity. In several clinical studies consisting of small or large sample sizes, several discrepancies exist regarding a significant positive correlation between the Ct value and disease severity in COVID-19. In this context, a revised review of the literature has been conducted to fill the knowledge gaps regarding the correlations between Ct values and severity/fatality rates of patients with COVID-19. Various databases such as PubMed, Science Direct, Medline, Scopus, and Google Scholar were searched up to April 2021 by using keywords including “RT-PCR or viral load”, “SARS-CoV-2 and RT-PCR”, “Ct value and viral load”, “Ct value or COVID-19”. Research articles were extracted and selected independently by the authors and included in the present review based on their relevance to the study. The current narrative review explores the correlation of Ct values with mortality, disease progression, severity, and infectivity. We also discuss the factors that can affect these values, such as collection technique, type of swab, sampling method, etc.

Abstract Despite recent landmark advances in T-cell immunotherapy for the treatment of human cancer, metastatic solid tumors remain an intractable challenge. Macrophages are often the most abundant immune cell in the tumor microenvironment (TME), where they may convert into immunosuppressive (M2) tumor-associated macrophages (TAMs) and participate in disease progression. Currently, macrophage-orientated immunotherapeutic approaches under clinical development in oncology seek to reduce TAM infiltration (CSF-1 antagonists) or enhance TAM phagocytosis (CD47 antagonists). Transfer of autologous, activated, but nontargeted macrophages failed to demonstrate antitumor efficacy in past clinical trials. We hypothesized that genetically engineering human macrophages with CARs against tumor-associated antigens could redirect their phagocytic activity and lead to therapeutic efficacy with the potential for the induction of an antitumor T-cell response. We first demonstrate that CD3-zeta-based CARs are capable of inducing phagocytosis in human THP-1 macrophages, while truncated intracellular-domain deficient CARs were not. Targeted phagocytosis and clearance of CD19+, mesothelin +, and HER2+ cells by CARs targeted against each respective antigen was significantly superior to that by control untransduced (UTD) macrophages. We demonstrate that primary human macrophages, which are resistant to most viral vectors, are efficiently transduced by the chimeric fiber adenoviral vector Ad5f35 (~70% in 10 normal donors). Using Ad5f35, we engineered primary human macrophages with a CD3-zeta-based CAR against HER2. Anti-HER2 primary human CAR macrophages demonstrated targeted phagocytosis against HER2+ but not HER2- cell lines, with phagocytic activity dependent on both the CAR and antigen densities. Furthermore, CAR, but not UTD, macrophages led to potent dose-dependent killing of three distinct HER2-high cell lines in vitro. We sought to test the efficacy of anti-HER2 primary human macrophages in xenograft models of human HER2+ ovarian cancer. A single dose of CAR, but not UTD macrophages, led to tumor regression and improved overall survival in both intraperitoneal and disseminated models of disease. We show that macrophage transduction with Ad5f35, a double-stranded DNA virus, leads to a broad gene expression change, an interferon signaling signature, and phenotypic clustering toward classically activated M1 macrophages. CAR macrophages upregulated co-stimulatory ligand and antigen processing/presentation genes and led to enhanced T-cell stimulation in vitro and in vivo. Lastly, CAR, but not UTD, macrophages showed a broad resistance for M2 conversion in response to immunosuppressive cytokines. In conclusion, we show that primary human CAR macrophages are capable of targeted tumor phagocytosis, lead to improved overall survival in xenograft models, and demonstrate enhanced T-cell stimulation. CAR macrophages are a novel cell therapy platform for the treatment of human cancer. This abstract is also being presented as Poster B29. Citation Format: Michael Klichinsky, Marco Ruella, Olga Shestova, Andrew Best, Kristin Blouch, Xueqing M. Lu, Saad S. Kenderian, Miriam Y. Kim, Roddy O'Connor, Stephen Wallace, Miroslaw Kozlowski, Dylan M. Marchione, Maksim Shestov, Benjamin A. Garcia, Carl June, Saar Gill. Human chimeric antigen receptor (CAR) macrophages for cancer immunotherapy [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr PR07.

Abstract Introduction Because of the improved colorectal cancer (CRC) survival in the U.S., patients may live long enough after CRC diagnosis to the point where non–cancer-related comorbidities may considerably impact their overall survival. In this study, we perform a long-term analysis of causes of death (CODs) following nonmetastatic CRC with respect to different demographic and tumor-related criteria. Materials and Methods We gained access to the Surveillance, Epidemiology, and End Results data to review patients diagnosed with nonmetastatic CRC during 2000–2015. We calculated standardized mortality ratios (SMRs) for each COD following CRC. SMRs represented the change of risk of a specific COD following CRC diagnoses when compared with the risk in the general U.S. population. Results We reviewed 302,345 patients, of whom 112,008 died during the study period. More deaths (68.3%) occurred within 5 years following nonmetastatic CRC diagnosis, with 76,486 deaths. CRC was the most common COD (51.4%) within 5 years of diagnosis followed by heart disease (15.2%) and other cancers (8.4%). As time passed after diagnosis, the number of CRC deaths decreased, and other noncancer causes increased to the point that after 10 years only 10.4% of deaths were attributed to CRC, 15.3% were attributed to other cancers, and 34.2% were secondary to heart disease. Conclusion Following nonmetastatic CRC diagnosis, most deaths remain secondary to CRC. Other causes, including other cancers and cardiovascular disease, represent a significant number of deaths, especially in the 5 years following initial CRC diagnosis. Our findings help guide counseling patients with CRC regarding future health risks. Implications for Practice Most common causes of death following nonmetastatic colorectal cancer (CRC) are heart diseases, other cancers, chronic obstructive pulmonary disease, and cerebrovascular diseases. Physicians should counsel patients regarding survivorship with cancer screening and focus on prevention of noncancer deaths. These findings should be considered by physicians who give care for survivors of nonmetastatic CRC.

8030 Background: CARTITUDE-1 is a single arm study of Ciltacabtagene autoleucel (cilta-cel; JNJ-68284528) anti-BCMA CAR-T cell therapy in US patients (pts) with relapsed multiple myeloma (RRMM) refractory to both IMiD and proteasome inhibitor (PI) or with at least 3 prior lines of therapy and previously exposed to anti-CD38 monoclonal antibody (MoAb). While recently reported efficacy results of cilta-cel were encouraging, it is unknown how they compare with similar pts receiving conventional (non CAR-T) treatment. Methods: We utilized a contemporary US-based dataset of pts with MM refractory to anti-CD38 MoAb (MAMMOTH) to identify pts who would meet eligibility for CARTITUDE-1 and who received conventional therapy. We analyzed the intent-to-treat population (ITT) in CARTITUDE-1, defined as pts who underwent apheresis (N=113) and a modified ITT population (mITT) defined as subset of pts who received cilta-cel at the RP2D (N=97). From the MAMMOTH dataset, we identified a population corresponding to CARTITUDE-1 ITT (N=190) and a mITT population, pts without death or progression within 47 days (median time between apheresis and cilta-cel infusion) from onset of therapy (N=122). We calculated propensity scores (PS) with demographics, N of prior therapies, cytogenetics and refractoriness to MM agents as covariates. An analyst blinded to outcomes performed nearest neighbor 1:1 PS matching. We analyzed overall response rate (ORR), progression-free (PFS) and overall survival (OS) for ITT and mITT in CARTITUDE-1 vs matching MAMMOTH cohorts. Results: Ninety-five ITT (75 received bridging therapy, 82 received cilta-cel) and 69 mITT (54 received bridging) CARTITUDE-1 pts matched MAMMOTH pts (Table). Among the pts in the MAMMOTH ITT cohort 34% received pomalidomide, 24% anti-CD38 MoAb, 19% carfilzomib and 35% cytotoxic chemotherapy in next therapy. ORR in the ITT cohorts was higher in CARTITUDE-1 (84% vs. 28%). Compared to their MAMMOTH counterparts, pts in CARTITUDE-1 ITT cohort had improved PFS (12 mo. 73% vs. 12%) and OS (12 mo. 83% vs 39%). Between the mITT cohorts, CARTITUDE-1 pts had superior ORR (96% vs. 30%), PFS (12 mo 79% vs. 15%) and OS (12 mo. 88% vs. 41%). Conclusions: In pts with RRMM beyond therapy with IMID, PI, and anti-CD38 MoAb, treatment with cilta-cel is associated with higher response rate and superior PFS and OS when compared to conventional treatment.[Table: see text]

8005 Background: CARTITUDE-1 (NCT03548207) is a phase 1b/2 study evaluating ciltacabtagene autoleucel (cilta-cel; JNJ-68284528), a CAR T-cell therapy with two BCMA–targeting single-domain antibodies, in patients (pts) with R/R MM. Here, we report updated results in pts with a longer duration (median 12.4 months) of follow-up. Methods: Eligible pts had MM and received ≥3 prior regimens or were double refractory to a proteasome inhibitor (PI) and immunomodulatory drug (IMiD), and had received a PI, IMiD, and anti-CD38 antibody. After apheresis, bridging therapy was permitted. Pts received a single cilta-cel infusion (target dose: 0.75×106 CAR+ viable T cells/kg; range 0.5-1.0×106) 5–7 days (d) after lymphodepletion (300 mg/m2 cyclophosphamide, 30 mg/m2 fludarabine daily for 3 d). The primary objectives were to characterize cilta-cel safety, confirm the recommended phase 2 dose (RP2D; phase 1b), and evaluate efficacy (phase 2). Cytokine release syndrome (CRS) was graded by Lee et al (Blood 2014) and neurotoxicity by CTCAE, v5.0 (in phase 1b). CRS and ICANS were graded by ASTCT criteria (in phase 2). Here, Lee et al and CTCAE v5.0 were mapped to ASTCT for CRS and ICANS, respectively. Results: As of Sept 1, 2020, 97 pts with a median of 6 prior lines received cilta-cel. Overall response rate per independent review committee (primary endpoint) was 97% (95% CI, 91–99), with 67% achieving stringent complete response (sCR). Median time to first response was 1 month (range, 1–9), and median time to CR or better was 2 months (range, 1–15). Responses deepened over time, and median duration of response was not reached. Of 57 pts evaluable for minimal residual disease (MRD) assessment, 93% were MRD-negative at 10-5. The 12-month progression-free survival (PFS) and overall survival rates (95% CI) were 77% (66–84) and 89% (80–94), respectively; median PFS was not reached. Grade 3/4 hematologic AEs ≥20% included neutropenia (95%), anemia (68%), leukopenia (61%), thrombocytopenia (60%), and lymphopenia (50%). CRS occurred in 95% of pts (4% grade 3/4), with median time to onset of 7 d (range, 1–12), and median duration of 4 d (range, 1–14, excluding 1 pt with 97-d duration). CRS resolved in all but one with grade 5 CRS/haemophagocytic lymphohistiocytosis. CAR T-cell neurotoxicity occurred in 21% of pts (grade ≥3, 10%). Fourteen deaths occurred during the study after cilta-cel infusion: none within the first 30 days, 2 within 100 days; and 12 more than 100 days post infusion, of which 5 were due to disease progression, and 4 due to treatment-related AEs. Conclusions: A single infusion of cilta-cel yielded early, deep, and durable responses in heavily pretreated pts with MM, with a manageable safety profile at the RP2D. Cilta-cel is under further investigation in other MM populations in earlier lines of therapy and in outpatient settings. Clinical trial information: NCT03548207.

7558 Background: A low absolute lymphocyte to monocyte ratio (ALC/AMC) has been found to predict decreased survival in lymphoma patients receiving chemotherapy and stem cell transplant. We report its clinical significance and additional cellular phenotype changes in patients receiving chimeric antigen receptor T-cell (CART) therapy. Methods: Records were reviewed for patients (pts) who received axicabtagene ciloleucel between 6/2016 and 12/2020. Receiver operator curve was generated using nominal logistic regression to predict CR as best response. Survivals were calculated using Kaplan- Meier method. Blood immune phenotype were assayed by multiparametric flow. Principle component analysis (PCA) was performed using ClusterVis. Results: Low ALC/AMC (≤0.8) prior to lymphodepletion (LD) chemotherapy on day -5 was associated with lower CR rate (AUC=0.68, Table). Our cohort of 81 pts had similar baseline characteristics except that noted in Table. Low ALC/AMC ratio is associated with shorter EFS and OS (EFS: 2.6 vs. 6.4 months, P<0.0001; OS: 5.3 months vs. not reached, P=0.0006), respectively. Prognostic association remained significant in multivariate analysis including ASCT, bridging therapy and CRP. Interestingly, compared to the high ALC/AMC group, the low ALC/AMC group had decreased CD8 Tem, increased CD16+CCR2+ monocytes and increased monocytes’ producing IL12, IL-10, and IL-1β (n=26). Unsupervised PCA identified 3 clusters: 1. Low ALC/AMC, all non-CR; 2. High ALC/AMC, some non-CR; 3. High ALC/AMC, all CR. Compared to cluster 1 and 2, cluster 3 had increased CD4 Tnaive, CD8 Tcm and IL-17 producing CD4 T and NK cells. Conclusions: ALC/AMC is a clinically accessible test that is strongly associated with CAR-T response and survival. Immune characterization revealed that the biologic effect is not just associated with cell ratio. Increased inflammation has been found to negatively impact CAR-T response, with some cytokines known to be from the myeloid lineage. We show that CRP is elevated in the low ALC/AMC group with increased cytokine production by monocytes. In addition, presence of T cell subset and IL-17 producing cells, before LD, are associated with clinical response. Further investigation on optimizing host immunity may help improve clinical outcome with CAR-T.[Table: see text]

7554 Background: Chimeric antigen receptor T-cell therapy (CAR-T) are commonly administered inpatient due to concern for early onset cytokine release syndrome (CRS), especially with axicabtagene ciloleucel (axi-cel). We report Mayo Clinic Rochester experience for hospital-based outpatient (HBO) management of patients (pts) receiving axi-cel and identify opportunities for improvement. HBO is closely integrated with inpatient practice and includes the same specialty trained clinical team. It is the first point of contact 24/7 for pts and triage evaluations. Lymphodepletion chemotherapy and CAR-T infusion is given on HBO followed by daily monitoring till day 8 and thereafter, as clinically needed until admission criteria is met. Methods: We retrospectively analyzed database of pts who received axi-cel between 1/2018 and 1/2021. After 06/2020, remote patient monitoring (RPM) tools were implemented to collect patient-reported neurologic symptoms and vital signs via bluetooth-enabled devices 4 times daily through month 1. Adverse data trends are addressed by the HBO team. Results: Among 72 recipients, 89% received their cells outpatient; 8% remained outpatient for the entire month. CRS and neurotoxicity incidence were comparable to those reported from CIBMTR. Median time to first admission was 2 days (Table). Use of bridging therapy, increased CRP and LDH were associated with early admission (≤3 days). Median time to tocilizumab, steroid, oxygen support, vasopressor was 4 days after admission. Half of HBO visits required intervention such as blood transfusions, IV medications through the first month. Nine pts had enrolled in RPM to date; with 8 having evaluable data. With 4 scheduled entries/day, a median of 1 entry/day was skipped and 2 entries/day were answered incompletely. An average of 57 additional unscheduled entries were generated per pt. Among a median of 373 (range 91-522) readings per pt over the first month, 4% (2%-20%) of the readings generated alerts. An average of 4 alerts were seen within 48 hours prior to admission. Data including additional subjects will be presented at ASCO meeting. Conclusions: We report a feasible outpatient care model for management of axi-cel recipients with safe outcomes. Clinical characteristics associated with more aggressive disease are associated with likelihood of early admission. Early RPM experience suggest use of digital tools could improve monitoring compliance and may predict evolution to symptoms requiring escalation of care.[Table: see text]

TPS6093 Background: Since patients with early-stage oral cavity cancer (OCC; T1-2N0M0; AJCC 8th ed) have a 20-30% rate of occult nodal metastases despite clinical and radiographic assessment, standard of care treatment includes elective neck dissection (END). Many patients have comprehensive surgical management of the regional cervical nodal basin even though the majority of those necks (70-80%) will not contain disease. Assessment of draining first echelon lymph nodes by sentinel lymph node (SLN) biopsy (Bx), a less invasive surgical procedure, may provide an alternative to END, while potentially reducing morbidity and cost. A decisive clinical trial comparing SLN Bx versus END can focus the HNC clinical and research community and resources on establishing the standard of care for management of the neck in early-stage OCC. Methods: In order to address the efficacy of SLN Bx in this population, we recently activated an international multi-institutional phase II/III prospective trial randomizing patients to two surgical arms: SLN Bx and END. PET/CT is an integral imaging biomarker in this trial. A node-negative PET/CT study with central read is required before randomization. Patients with a positive PET/CT central result will remain in a registry to compare imaging findings with final neck pathology. Given the current evidence available regarding morbidity for SLN Bx versus END, the phase II will determine if patient-reported neck and shoulder function and related QOL at 6 months after surgery using the Neck Dissection Impairment Index (NDII) shows a signal of superiority of SLN Bx compared to END. A total of 228 randomized patients with negative PET/CT for potential evaluation of shoulder-related morbidity with difference in 6-month NDII scores (minimum important difference ³7.5; one-sided a = 0.10; 90% power) will serve as the “Go/No-Go” decision to move forward into phase III. The phase III portion is a non-inferiority (NI) trial with disease-free survival (DFS) as the primary endpoint (NI margin hazard ratio 1.34 based on a 5% absolute difference in 2-year DFS; one-sided alpha 0.05; 80% power, and an interim look for efficacy at 67% of the events based on an O’Brien-Fleming boundary). The NDII at 6 months after surgery is a hierarchical co-primary endpoint for the phase III. Target accrual of phase III is 618 PET/CT negative patients, including those randomized in phase II (297 DFS events required for the final analysis). In addition to radiotherapy and imaging credentialing, quality assurance will include central pathology review of all negative SLN Bx cases and surgeon credentialing through an education course and SLN Bx and END case review by the surgical co-chairs. A surgical quality assurance working group will review all trial SLN Bx and END outcomes. As of 02/15/21, 7 patients have been screened and 6 of the planned 228 randomized patients in phase II have been enrolled. Clinical trial information: NCT04333537.