Citations

Background: Proton beam therapy offers radiophysical properties that are appealing for noninvasive arrhythmia elimination. This study was conducted to use scanned proton beams for ablation of cardiac tissue, investigate electrophysiological outcomes, and characterize the process of lesion formation in a porcine model using particle therapy. Methods: Twenty-five animals received scanned proton beam irradiation. ECG-gated computed tomography scans were acquired at end-expiration breath hold. Structures (atrioventricular junction or left ventricular myocardium) and organs at risk were contoured. Doses of 30, 40, and 55 Gy were delivered during expiration to the atrioventricular junction (n=5) and left ventricular myocardium (n=20) of intact animals. Results: In this study, procedural success was tracked by pacemaker interrogation in the atrioventricular junction group, time-course magnetic resonance imaging in the left ventricular group, and correlation of lesion outcomes displayed in gross and microscopic pathology. Protein extraction (active caspase-3) was performed to investigate tissue apoptosis. Doses of 40 and 55 Gy caused slowing and interruption of cardiac impulse propagation at the atrioventricular junction. In 40 left ventricular irradiated targets, all lesions were identified on magnetic resonance after 12 weeks, being consistent with outcomes from gross pathology. In the majority of cases, lesion size plateaued between 12 and 16 weeks. Active caspase-3 was seen in lesions 12 and 16 weeks after irradiation but not after 20 weeks. Conclusions: Scanned proton beams can be used as a tool for catheter-free ablation, and time-course of tissue apoptosis was consistent with lesion maturation.

Abstract Structural grey matter covariance networks provide an individual quantification of morphological patterns in the brain. The network integrity is disrupted in sporadic Alzheimer’s disease, and network properties show associations with the level of amyloid pathology and cognitive decline. Therefore, these network properties might be disease progression markers. However, it remains unclear when and how grey matter network integrity changes with disease progression. We investigated these questions in autosomal dominant Alzheimer’s disease mutation carriers, whose conserved age at dementia onset allows individual staging based upon their estimated years to symptom onset. From the Dominantly Inherited Alzheimer Network observational cohort, we selected T1-weighted MRI scans from 269 mutation carriers and 170 non-carriers (mean age 38 ± 15 years, mean estimated years to symptom onset −9 ± 11), of whom 237 had longitudinal scans with a mean follow-up of 3.0 years. Single-subject grey matter networks were extracted, and we calculated for each individual the network properties which describe the network topology, including the size, clustering, path length and small worldness. We determined at which time point mutation carriers and non-carriers diverged for global and regional grey matter network metrics, both cross-sectionally and for rate of change over time. Based on cross-sectional data, the earliest difference was observed in normalized path length, which was decreased for mutation carriers in the precuneus area at 13 years and on a global level 12 years before estimated symptom onset. Based on longitudinal data, we found the earliest difference between groups on a global level 6 years before symptom onset, with a greater rate of decline of network size for mutation carriers. We further compared grey matter network small worldness with established biomarkers for Alzheimer disease (i.e. amyloid accumulation, cortical thickness, brain metabolism and cognitive function). We found that greater amyloid accumulation at baseline was associated with faster decline of small worldness over time, and decline in grey matter network measures over time was accompanied by decline in brain metabolism, cortical thinning and cognitive decline. In summary, network measures decline in autosomal dominant Alzheimer’s disease, which is alike sporadic Alzheimer’s disease, and the properties show decline over time prior to estimated symptom onset. These data suggest that single-subject networks properties obtained from structural MRI scans form an additional non-invasive tool for understanding the substrate of cognitive decline and measuring progression from preclinical to severe clinical stages of Alzheimer’s disease.

ABSTRACT Background Implementation of checklists has been shown to be effective in improving patient safety. This study aims to evaluate the effectiveness of implementation of a checklist for daily care processes into clinical practice of pediatric intensive care units (PICUs) with limited resources. Methods Prospective before–after study in eight PICUs from China, Congo, Croatia, Fiji, and India after implementation of a daily checklist into the ICU rounds. Results Seven hundred and thirty-five patients from eight centers were enrolled between 2015 and 2017. Baseline stage had 292 patients and post-implementation 443. The ICU length of stay post-implementation decreased significantly [9.4 (4–15.5) vs. 7.3 (3.4–13.4) days, p = 0.01], with a nominal improvement in the hospital length of stay [15.4 (8.4–25) vs. 12.6 (7.5–24.4) days, p = 0.055]. The hospital mortality and ICU mortality between baseline group and post-implementation group did not show a significant difference, 14.4% vs. 11.3%; p = 0.22 for each. There was a variable impact of checklist implementation on adherence to various processes of care recommendations. A decreased exposure in days was noticed for; mechanical ventilation from 42.6% to 33.8%, p < 0.01; central line from 31.3% to 25.3%, p < 0.01; and urinary catheter from 30.6% to 24.4%, p < 0.01. Although there was an increased utilization of antimicrobials (89.9–93.2%, p < 0.01). Conclusions Checklists for the treatment of acute illness and injury in the PICU setting marginally impacted the outcome and processes of care. The intervention led to increasing adherence with guidelines in multiple ICU processes and led to decreased length of stay.

8547 Background: Venetoclax (Ven) is a selective, potent BCL-2 inhibitor that has synergistic activity with bortezomib (B) and dexamethasone (d). In the Phase 3 BELLINI trial, addition of Ven to Bd significantly improved median progression-free survival (PFS) and response rates, including minimal residual disease (MRD) negativity, but resulted in increased mortality vs placebo (Pbo). Here, we determine whether MRD negativity was associated with longer PFS and OS in relapsed/refractory multiple myeloma (RRMM) patients treated with Ven+Bd in the BELLINI dataset. Methods: In BELLINI (NCT02755597), RRMM patients (pts) sensitive or naïve to proteasome inhibitors with 1-3 prior lines of therapy were randomized 2:1 to Ven (800 mg) or Pbo plus B (1.3 mg/m2) and d (20 mg). Next-gen sequencing MRD assessments were done on bone marrow aspirates at the time of suspected CR/sCR, and 6- and 12-months post confirmation of CR/sCR. Patients with a missing or indeterminate assessment were considered MRD positive. Evaluation of MRD in biomarker-defined subgroups (cytogenetics and BCL2 expression) was also performed and will be presented. Results: In total, 291 pts were randomized; 194 to Ven, 97 to Pbo. As of 13 Sep 2019, the median follow-up was 29 months. Ven + Bd demonstrated significantly higher MRD negativity rates ( < 10−5), including a higher proportion of pts achieving sustained MRD negativity (Table). In the Ven arm, the median (m)PFS was not reached for MRD negative pts vs 16.2 months for MRD positive pts (HR = 0.23, 95% CI: 0.10-0.54, p < 0.001). While the mOS was not reached in the Ven arm, OS was significantly longer for MRD negative vs MRD positive pts (HR = 0.25, 95% CI: 0.08-0.80, p = 0.0194). Conclusions: The addition of Ven to Bd resulted in deep and durable responses, including higher rates of MRD negativity. MRD negativity in the context of Ven was associated with prolonged survival in patients with RRMM, consistent with the broader MRD body of evidence with other therapies in MM. Clinical trial information: NCT02755597 . [Table: see text]

8546 Background: The PI bortezomib is commonly used in first-line therapy of AL, but new therapies are needed that are tolerable in the context of multi-organ dysfunction and that, in RRAL, offer improved outcomes following prior bortezomib. Ixazomib is an oral PI, and in TOURMALINE-AL1, the first phase 3 trial conducted in RRAL, while the first primary endpoint of hematologic overall response rate (ORR) was not met, all clinically relevant time-to-event endpoint data favored Ixa-Dex vs PC (Dispenzieri et al, ASH 2019). Methods: RRAL pts with 1–2 prior therapies were randomized (1:1) to Ixa-Dex (n = 85) or PC (n = 83; Dex plus lenalidomide [n = 47], melphalan [n = 24], cyclophosphamide [n = 10], or thalidomide [n = 2]), stratified by cardiac stage, relapsed vs refractory disease, and prior PI exposure. The primary endpoints were hematologic ORR and 2-yr rate of vital organ deterioration or death. We report subgroup analyses of ORR and outcomes by prior PI exposure. Results: Of the 168 pts enrolled, 90 were PI-naïve and 78 PI-exposed (46 and 39 in the Ixa-Dex arm; 44 and 39 in the PC arm) per stratification; 28 and 27 pts in the Ixa-Dex and PC arms had received bortezomib in their last prior line. Hematologic ORR was 63% vs 50% for Ixa-Dex vs PC (odds ratio [OR] 1.71; 95% confidence interval [CI] 0.74–3.96) in PI-naïve pts, and 41% vs 51% (OR 0.66; 95% CI 0.27–1.62) in PI-exposed pts. For time-to-event outcomes (Table), hazard ratios (HRs) were 0.46–0.85 in favor of Ixa-Dex vs PC in both PI-naïve and PI-exposed pts. Conclusions: Hematologic ORR was higher with Ixa-Dex vs PC in PI-naïve pts but lower in PI-exposed pts (although not statistically significant), and long-term clinically relevant outcomes favored Ixa-Dex in both groups. Based on HRs, the magnitude of benefit appeared similar or greater in PI-naïve vs PI-exposed pts. Clinical trial information: NCT01659658 . [Table: see text]

8509 Background: Venetoclax (Ven) is a selective, potent, oral BCL-2 inhibitor. In the Phase 3 BELLINI trial, addition of Ven to bortezomib (B) + dexamethasone (d) significantly improved response rates and progression-free survival (PFS) vs placebo (Pbo) and showed significant efficacy in patients (pts) with either t(11;14) or BCL2high gene expression. Here we present updated safety and efficacy data from the prespecified second interim overall survival (OS) analysis. Methods: In this multicenter, randomized, double-blind study (NCT02755597), pts with relapsed/refractory multiple myeloma (RRMM) with 1-3 prior lines of therapy were randomized 2:1 to Ven (800 mg) or Pbo in combination with B (1.3 mg/m2) and d (20 mg). The primary endpoint was PFS; key secondary endpoints included overall response and overall survival (OS). Results: 291 pts were randomized; 194 to Ven, 97 to Pbo. Pt characteristics were well balanced among arms. In the Ven arm, median age was 66, 17% had high-risk cytogenetics, 11% had t(11;14), and 34% had BCL2high gene expression. As of 13 Sept 2019, 59 pts were still on study, 45 (23%) Ven vs 14 (14%) Pbo. At a median follow-up of 28.6 months, there were 64 (33%) deaths in the Ven arm vs 24 (25%) in Pbo. At the initial data cutoff (26 Nov 2018), PFS HR was 0.63 (0.44,0.90) and OS HR was 2.03 (1.04,3.95). Table shows updated PFS and OS. Most common treatment-emergent adverse events (TEAEs) with Ven were diarrhea (59%), nausea (37%), and constipation (35%). Most common grade 3/4 AEs (Ven/Pbo) were neutropenia (21%/8%), thrombocytopenia (15%/30%), anemia (16%/15%), diarrhea (15%/12%), and pneumonia (18%/13%). Serious AEs occurred in 54% Ven and 52% Pbo pts. 24% discontinued Ven due to AEs vs 12% Pbo. There were 14 treatment-emergent deaths in the Ven arm and 1 in Pbo. Conclusions: The addition of Ven to Bd significantly improves PFS but resulted in increased mortality vs Pbo in the total population. Greatest PFS improvement with Ven was observed in pts with t(11;14) or BCL2high gene expression, where Ven shows a favorable benefit-risk profile. The study continues for final OS analysis. Clinical trial information: NCT02755597 . [Table: see text]

3537 Background: Bevacizumab (BV) prolongs overall survival and progression-free survival (PFS) when added to standard chemotherapy (CT) in patients with metastatic colorectal cancer (mCRC). BRiTE is a large, community-based observational registry of patients with mCRC receiving BV plus first-line CT. Safety and efficacy information in unselected patients with mCRC are collected. Chemotherapy regimen choice is at the physician’s discretion. Methods: 1968 patients receiving BV plus first-line CT were enrolled at 248 sites in 49 states between Feb 2004 and Jun 2005. Patients are followed for up to 3 years, with data reporting every 3 months (mo) including disease status as assessed by investigator using his/her method of choice. Patients were grouped twice by CT. Cox regression models, adjusted and unadjusted for treatment assignment, were used to identify baseline characteristics (BC) and differential chemotherapy effects on PFS. Results: Cohort demographics were consistent with the NCI Surveillance, Epidemiology, and End Results (SEER) database for mCRC. Median study follow-up was 10 months by Nov 4, 2005. CT regimens included FOLFOX (55.8%), FOLFIRI (14.1%), and IFL (9.7%). Based on observed progression events (n=800) or deaths (n=123), projected median PFS is 11.3 mo (95% CI: 10.4–11.7). Median PFS was comparable in patients treated with CT regimen based on irinotecan (11.3 mo), oxaliplatin (11.4 mo), or neither (10.2 mo) (CT Grouping 1); or 5FU infusion (11.5 mo), 5-FU bolus (9.7 mo), or capecitabine (11.6 mo) (CT Grouping 2). Significant BC in adjusted and unadjusted models are ECOG performance status (PS), primary disease site, and albumin, with no significant difference among CT regimens. Conclusions: This large, community-based registry included a patient population with demographics consistent with the SEER database for mCRC. Preliminary median PFS of 11.3 mo compares favorably to that reported in the pivotal trial. Median PFS appears to be comparable for all CTs when combined with BV. Higher baseline albumin, PS of 0, and primary disease site of rectum were associated with improved outcome. [Table: see text]

3536 Background: Bevacizumab (BV) prolongs overall survival and progression-free survival when added to standard chemotherapy for patients with metastatic colorectal cancer (mCRC). BRiTE is a large, community-based observational registry of patients with mCRC receiving BV plus first-line chemotherapy. Safety and efficacy information in unselected patients with mCRC are collected. Chemotherapy regimen choice is at the physician’s discretion. Methods: To facilitate and evaluate enrollment of a typical community-based mCRC population, eligibility criteria were minimized. Cohort demographics were consistent with the NCI Surveillance, Epidemiology, and End Results (SEER) database for mCRC. Patients are followed for up to 3 years, and safety data including targeted BV-associated serious adverse events (SAEs) are updated every 3 months (mo). Results are based on descriptive analyses and are not adjusted for propensity of treatment, baseline characteristics, and treatment effects. Results: 1968 patients were enrolled between Feb 2004 and Jun 2005. Median study follow-up was 10 mo by Nov 4, 2005. SAEs were reported in 12.0% of patients including gastrointestinal perforation (GIP) (1.7%), postoperative bleeding/wound healing complications (1.2%), arterial thromboembolic events (ATE) (2.1%), and grade 3–4 bleeding (1.9%). 3.2% of patients discontinued BV due to a BV-related toxicity, most commonly bleeding. For patients with the respective event(s), median time to first event was 2.1 mo for GIP, 3.5 mo for ATE and 4.0 mo for grade 3–4 bleeding. 8.9% of patients with no history of hypertension (HTN) developed HTN requiring medication and 6.2% of patients who had HTN requiring medication at baseline experienced worsening of their HTN while on study treatment. Conclusions: In this unselected population of patients with mCRC, the safety profile of BV plus various chemotherapy regimens appears consistent with that observed in the pivotal BV trial. Overall discontinuation of BV due to a BV-related toxicity was uncommon. In this large community-based observational registry, no new BV associated safety issues have been identified. [Table: see text]