Citations

Abstract OBJECTIVE The K16ApoE peptide enhances delivery of multiple agents across the blood-brain barrier (BBB). Transgenic mouse models are central to elucidating the underlying pathophysiology of Alzheimer’s Disease (AD) and provide a system for evaluating novel therapeutic strategies. PET imaging plays a central clinical role in diagnosing human cases of AD but has had variable performance in mouse models. We investigated the role of K16ApoE to enhance delivery of a radiolabeled PET imaging tracer, 11C-PiB and assess whether this corresponds to improved PET sensitivity in APP/PS1 transgenic mice. METHODS Brain-delivery of 11C-PiB was accomplished by successive injections of K16ApoE and 11C-PiB. Distribution of 11C-PiB to the brain and heart was quantified via dynamic PET/CT imaging and digital autoradiography. RESULTS K16ApoE increased the brain uptake of 11C-PiB in both wild-type (WT) and APP/PS1 mice. Administration of K16ApoE increased the PET standard uptake value of 11C-PiB at 5 minutes in WT mice from 1.132 to 2.963 (p=0.006) and in APP/PS1 mice from 0.842 to 3.268 (p=0.016). Enhancement peaked at 5 minutes. Binding was reversible with similarly increased kinetics in both WT and APP/PS1 mice. The absolute values were higher in APP/PS1 mice suggesting increased retention. The increased retention in APP/PS1 mice was consistent with specific binding to A-beta plaques as unlabeled PiB reduced 11C-PiB signal retention. CONCLUSION K16ApoE mediates enhancement of 11C-PiB signal in APP/PS1 mice brains with increased PET sensitivity. There is increased uptake kinetics in both WT and APP/PS1 mice with specific A-beta plaque binding in the latter. This enhanced delivery of the PET tracer has implications for development and testing of new hypotheses and the efficacy of novel therapeutic paradigms. K16ApoE has potential for improving delivery of several agents across the BBB. This has implication for delivery of diagnostic and therapeutic agents for neurodegenerative and neuro-oncologic diseases.

Abstract Abstract 2477 Background: Aurora A kinase (AAK) is a key mitotic regulator, inhibition of which results in mitotic spindle defects, mitotic delay, and apoptosis. AAK is amplified or overexpressed in a number of heme-lymphatic malignancies. This phase 1, multicenter study (NCT00697346) is the first to assess safety, tolerability, and pharmacokinetics (PK) of the investigational AAK inhibitor alisertib (MLN8237) in patients with advanced hematologic malignancies. Methods: Patients aged ≥18 years with relapsed/refractory hematologic malignancy, confirmed radiographically or clinically evaluable disease, and ECOG performance status 0–2, were eligible for inclusion. Patients with prior allogeneic transplant were excluded; there was no restriction on the number of prior therapies. Patients received escalating doses (standard 3+3 design) of alisertib as either a powder-in-capsule (PIC) or enteric coated tablet (ECT) formulation. Alisertib PIC was administered as a twice-daily (BID) loading dose on Day 1, then once daily (QD) on Days 2–14 or 2–21, followed by 14 or 7 days' rest, respectively, in 28-day cycles. Alisertib ECT administration followed the same scheme in the first dose group, and subsequent groups received divided (BID) doses for 7 days plus 14 days' rest in 21-day cycles. Endpoints included maximum tolerated dose (MTD), dose-limiting toxicity (DLT), safety, PK, and response. Results: 55 patients were included (PIC n=28, ECT n=27); median age was 61 years (range 27–82), 42% had prior ASCT, and 78% had received ≥3 prior therapies. 60% of patients had non-Hodgkin's lymphoma, 35% multiple myeloma, and 5% chronic lymphocytic leukemia/small lymphocytic lymphoma. Patients received a median of 2 cycles (range 1–14); 8 patients are ongoing. The MTD on the alisertib PIC 14-day + 14 days' rest schedule was 45 mg QD, established following occurrence of DLTs in four patients at higher dose levels: Gr 4 thrombocytopenia, Gr 4 neutropenia (65 mg QD); Gr 3 febrile neutropenia, Gr 4 thrombocytopenia (90 mg QD). In patients receiving alisertib ECT, the MTD was determined as 50 mg BID on a 7-day + 14 days' rest schedule; four DLTs were observed in three patients: at 40 mg QD for 14 days, one patient had Gr 4 febrile neutropenia, and one patient had Gr 4 bullous dermatitis and Gr 4 neutropenia; at 50 mg BID for 7 days, one of nine patients had Gr 4 neutropenia. The most common drug-related adverse events (AEs) were neutropenia (PIC 46%, ECT 63%), thrombocytopenia (39%, 41%), and diarrhea (29%, 41%); most common Gr ≥3 drug-related AEs were neutropenia (PIC 36%, ECT 52%), thrombocytopenia (29%, 26%), and anemia (14%, 26%). 24 patients (PIC n=12, ECT n=12) had serious AEs; the most common was febrile neutropenia (PIC n=1, ECT n=4). Tolerability appeared generally similar between the PIC and ECT formulations. Six patients (PIC n=3, ECT n=3) died during the study (PIC: renal failure, airway obstruction, progressive large cell lymphoma; ECT: progressive myeloma [n=2], hypercalcemia); no deaths were considered to be related to alisertib. Alisertib absorption was rapid with an overall median Tmax of 2 hours. The overall mean terminal half-life following multiple dosing was 19 hours. The mean peak/trough (P/T) ratio was 5 following QD dosing as PIC. The mean accumulation ratio and P/T ratio were 2.5 and 2.1, respectively, following BID dosing as ECT. At data cut-off (29 March, 2011), 42 patients were evaluable for response. Antitumor activity was observed in five patients (PIC n=3, ECT n=2) who had partial responses; 11 patients had a best response of stable disease (PIC n=6, ECT n=5) and 26 had progressive disease (PIC n=14, ECT n=12). Seven patients received ≥5 cycles of therapy, including one patient (PIC group; post-transplant grade 3B follicular lymphoma) with resolution of B symptoms who received alisertib for >1 year. Conclusions: The MTDs of the PIC and ECT formulations of alisertib are 45 mg QD for 14 days (+14 days' rest) and 50 mg BID for 7 days (+ 14 days' rest), respectively, in patients with advanced, non-leukemic hematologic malignancies. AEs were generally manageable and were consistent with inhibition of AAK in highly proliferative tissues (gastrointestinal and hematologic AEs). Current data support further investigation and expansion at the MTDs is ongoing. Data from PK, safety, and tolerability collectively support the progression of ECT formulation at 50 mg BID for 7 days in a 21-day cycle into phase 2 development. Disclosures: Off Label Use: Investigational agent in clinical development for the treatment of advanced hematologic malignancies and solid tumors. Goy:Millennium Pharmaceuticals, Inc.: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; GSK: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Genentech: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Reeder:Millennium Pharmaceuticals, Inc.: Institutional research funding; Novartis: Institutional research funding; Celgene: Institutional research funding. Zhou:Millennium Pharmaceuticals, Inc.: Employment. Danaee:Millennium Pharmaceuticals, Inc.: Employment. Xiao:Millennium Pharmaceuticals, Inc.: Employment. Benaim:Millennium Pharmaceuticals, Inc.: Employment, Equity Ownership. Shea:Millennium Pharmaceuticals, Inc.: Consultancy, Research Funding.

Abstract Abstract 2799 Background: Aurora A kinase (AAK) is important in a diverse set of mitotic processes and is amplified or overexpressed in a number of heme-lymphatic malignancies. MLN8237 is an investigational, orally administered, selective AAK inhibitor in clinical development for the treatment of hematologic and solid tumors. This multicenter study (NCT00697346) is the first phase 1 program to assess safety and pharmacology of MLN8237 in patients with advanced hematologic malignancies. Methods: Eligible patients were aged ≥18 yr, had response-evaluable, relapsed or refractory hematologic malignancies, and had ECOG performance status 0–2; there was no restriction on the number of prior therapies, but prior allogeneic transplant was excluded. Patients received escalating doses of MLN8237 as powder-in-capsule formulation in a 3+3 design. Endpoints included safety, dose-limiting toxicity (DLT), maximum tolerated dose (MTD), pharmacokinetics, and response. Results: Twenty-eight patients were included; median age was 62 yr (range 41–74), 50% were male, 86% were white, and 43% had prior transplant. Diagnoses were non-Hodgkin's lymphoma (68%), including diffuse large B-cell (DLBCL), mantle cell, follicular, and small lymphocytic lymphoma; multiple myeloma (29%); and chronic lymphocytic leukemia (4%). Seventy-nine percent of patients had received ≥3 prior therapies. Patients initially received a 21-day treatment schedule of MLN8237 25 or 35 mg (BID loading dose on Day 1, then QD on Days 2–21) followed by a 7-day rest period (28-day cycles). Based on results with the first two cohorts, subsequent cohorts received a 14-day treatment schedule of MLN8237 35, 45, 65, or 90 mg (BID loading dose on Day 1, then QD on Days 2–14) followed by a 14-day rest period (28-day cycles). Median number of cycles administered was 2 (range 1–14+). After escalation to 90 mg (maximum administered dose), two DLTs per cohort led to de-escalation to 65 mg and then 45 mg, which was the MTD on the 14-day schedule. The most common treatment-related adverse events (AEs) were neutropenia (46%), thrombocytopenia (36%), and asthenic conditions (32%); grade ≥3 treatment-related AEs were reported in 14 (50%) patients, and 13 (46%) had a serious AE. DLTs included grade 3–4 myelosuppression associated with infection or delay in treatment, which were generally manageable by reduction in dose or schedule. AEs were generally reversible and manageable, although 5 (18%) patients discontinued due to AEs. Three patients died, from causes (renal failure; airway obstruction; progressive large cell lymphoma) not considered related to MLN8237. Following multiple doses, an overall median Tmax of 2 hr, a mean t1/2 of 23 hr, and a peak/trough ratio of 5 were observed. The geometric mean of steady-state AUC increased from 19,534 to 30,811 nM*hr when the daily dose was increased from 25 to 65 mg. With the 14-day schedule, antitumor activity was observed in a patient with relapsed DLBCL treated with 65 mg and reduced to 45 mg, who enrolled after disease progression following ifosfamide-carboplatin-etoposide (ICE) salvage therapy. A durable PR coupled with resolution of B symptoms sustained for >1 yr was observed in a patient with post-transplant grade 3B follicular lymphoma treated with 35 mg, escalated per protocol to 45 mg and then 65 mg. Stable disease (SD; 5 months) was observed in a patient with myeloma treated at 90 mg. Conclusions: MLN8237 toxicities were consistent with AAK inhibition in proliferating tissue (chiefly bone marrow), and were generally manageable. The MTD was 45 mg on the 14-day schedule in these patients with advanced hematologic malignancies. Antitumor activity was observed, and repeat cycles were tolerable over 6–12 months in some patients who achieved PR or SD. The results support further investigation of MLN8237 in heme-lymphatic malignancies, and ongoing clinical development includes alternative schedules and formulations. Disclosures: Padmanabhan: Millennium Pharmaceuticals, Inc.: Consultancy, Research Funding. Off Label Use: Investigational agent in clinical development for the treatment of advanced hematologic malignancies. Shea:Millennium Pharmaceuticals, Inc: Consultancy, Research Funding. Vose:Millennium Pharmaceuticals, Inc.: Research Funding. Goy:Millennium Pharmaceuticals, Inc., Celgene, GSK, Genentech: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Zhou:Millennium Pharmaceuticals, Inc.: Employment. Liu:Millennium Pharmaceuticals, Inc.: Employment. Fingert:Millennium Pharmaceuticals, Inc.: Employment, Equity Ownership. Fowler:Millennium Pharmaceuticals, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics: Honoraria, Research Funding; Cephalon: Research Funding; Genentech: Honoraria, Research Funding; Celgene: Honoraria.

Abstract Abstract 750 Background: DKK1 is a negative regulator of the Wnt signaling pathway in bone that is overexpressed in a subset of newly-diagnosed MM patients with osteolytic lesions as well as in refractory and relapsed patients. Expression also correlates with the number of osteolytic lesions in untreated MM patients. BHQ880 is a novel anti-DKK1 human monoclonal antibody. Alleviation of DKK1 inhibition by BHQ880 results in activation of the Wnt signaling pathway, leading to increased bone mass mediated via upregulation of osteoblasts in mice and monkeys. In murine models of MM bone disease; this anabolic activity of BHQ880 increased trabecular and cortical bone density. Lytic bone disease in MM is caused by osteoclast activation and osteoblast inhibition. Current approved therapies for the treatment of MM bone disease are focused on osteoclast inhibition (e.g., bisphosphonates) and BHQ880 therapy may be able to reverse the effects of DKK1-induced osteoblast inhibition. Therefore, dual therapy with zoledronic acid to decrease bone resorption and BHQ880 to increase new bone formation may provide an effective treatment strategy for MM bone disease. Methods: In the phase I portion of this phase I/II study, patients with relapsed or refractory MM with prior skeletal-related event (SRE) were treated with BHQ880 as an IV infusion Q28 days. Patients also received Zol (4 mg) and approved MM Tx (bortezomib not allowed). Bone markers and total DKK1 levels along with bone mineral density are being measured. Full PK profiles were collected during the first and second cycle, after which predose (trough) samples were collected to assess accumulation. Results: Ten pts (6:M, 4:F), median age: 66.5 yrs (range 41- 70), performance status-0(5 pts), 1(4 pts), 2 (1 pts) have been enrolled in the following dose levels (mg/kg) 3 (2 pts), 10 (starting dose level -4 pts), 20 (4 pts) and have been on treatment for 1 day to 5 28-day cycles. No BHQ880-related AE's have been observed to date. Bone mineral density (BMD) data from the first two patients treated at 10 mg show the following: a.) Pt 1 (hip +5.8%, spine N/A due to surgery, wrist -1.8%); b.) Pt 2 (hip -0.2%, spine +6.1%, wrist not done). The biomarker data from these patients show: a.) Pt 1 shows a maximal +98% change over baseline in PINP at day 15 post-treatment, while osteocalcin (OC) changes +17% at day 15, reaching a +56% change over baseline at cycle 4 day 1; uNTx/Cr changes – 43 % at cycle 2 day 15. b) Partial data from Pt 2 suggests a -44 % change in PINP and –73 % change in OC and a +73% change in uNTx/Cr. Baseline total DKK1 levels on 3 patients ranged from 8.8 to 21.5 ng/mL. Preliminary PK analysis is available in 1 out of 3 patients treated at 10mg/kg. The Cmax achieved after the first infusion was 165 ug/mL and 201 ug/mL after the second infusion. Calculated t1/2 was 188 hours after the first infusion and 254 hours after the second infusion. Regarding overall exposure, AUC0-672 hours after first infusion was 36081 hr*ng/mL and 48533 hr*ng/mL after the second infusion. Conclusion: BHQ880 given IV Q28 days appears to be well tolerated in combination with Zol and chosen MM Tx. Once safety of 40 mg/kg BHQ880 or the MTD dose has been determined, pts will be enrolled in the phase II portion to assess activity on a SRE endpoint. Updated safety, efficacy, bone density and biomarker data will be presented on all patients at the upcoming ASH meeting. Disclosures: Padmanabhan: Genentech: Consultancy, Honoraria; GSK: Consultancy, Speakers Bureau; Celgene: Consultancy, Speakers Bureau. Off Label Use: BHQ880, a novel osteoblast activating, anti-DKK1 antibody. Dzik-Jurasz:Novartis: Employment, Equity Ownership. Gangolli:Novartis: Employment, Equity Ownership. Ettenberg:Novartis: Employment, Equity Ownership. Miner:Novartis: Employment, Equity Ownership. Bilic:Novartis: Employment, Equity Ownership. Whyte:Novartis: Employment, Equity Ownership. Mehdi:Novartis: Employment, Equity Ownership. Chiang:Novartis: Employment, Equity Ownership. Rae:Novartis: Employment, Equity Ownership. Shah:Novartis: Consultancy, Speakers Bureau; Celgene: Consultancy, Speakers Bureau; Millenium: Research Funding, Speakers Bureau; Amgen: Consultancy, Speakers Bureau; Elan: Consultancy. Giles:Novartis: Consultancy, Research Funding; BMS: Research Funding; Merck: Research Funding; Clavis: Research Funding. Stewart:Novartis: Consultancy; Amgen: Consultancy; Millenium: Consultancy, Research Funding; Proteolix: Consultancy; Celgene: Honoraria.

Acute aortic syndromes are a distinct group of pathologies involving the wall of the aorta that present acutely and can be potentially fatal unless treated in a timely fashion. The syndrome is dominated by aortic dissections, which comprise ≥95% of all such presentations. Those involving the ascending aorta are particularly lethal and require specific and early surgical treatment compared to dissections involving other parts of the aorta. The surgical repair of an ascending aortic dissection presents multiple challenges to the anesthesiologist. Thoughtful management throughout the perioperative period is critical for minimizing the significant morbidity and mortality associated with this condition. In this narrative review, we provide an overview of the perioperative management of patients presenting for the surgical repair of an ascending aortic dissection. Preoperative discussion focuses on assessment, hemodynamic management, and risk stratification. The intraoperative section includes an overview of anesthetic management, transesophageal echocardiographic assessment, and coagulopathy, as well as surgical considerations that may influence anesthetic management.

Impaired brain clearance of amyloid-beta peptides (Aβ) 40 and 42 across the blood–brain barrier (BBB) is believed to be one of the pathways responsible for Alzheimer’s disease (AD) pathogenesis. Hyperinsulinemia prevalent in type II diabetes was shown to damage cerebral vasculature and increase Aβ accumulation in AD brain. However, there is no clarity on how aberrations in peripheral insulin levels affect Aβ accumulation in the brain. This study describes, for the first time, an intricate relation between plasma insulin and Aβ transport at the BBB. Upon peripheral insulin administration in wild-type mice: the plasma clearance of Aβ40 increased, but Aβ42 clearance reduced; the plasma-to-brain influx of Aβ40 increased, and that of Aβ42 reduced; and the clearance of intracerebrally injected Aβ40 decreased, whereas Aβ42 clearance increased. In hCMEC/D3 monolayers (in vitro BBB model) exposed to insulin, the luminal uptake and luminal-to-abluminal permeability of Aβ40 increased and that of Aβ42 reduced; the abluminal-to-luminal permeability of Aβ40 decreased, whereas Aβ42 permeability increased. Moreover, Aβ cellular trafficking machinery was altered. In summary, Aβ40 and Aβ42 demonstrated distinct distribution kinetics in plasma and brain compartments, and insulin differentially modulated their distribution. Cerebrovascular disease and metabolic disorders may disrupt this intricate homeostasis and aggravate AD pathology.