GMP implementation of a hybrid continuous manufacturing process for a recombinant non-mAb protein-A case study.

Advances in manufacturing technology coupled with the increased potency of new biotherapeutic modalities have created an external environment where continuous manufacturing (CM) can address a growing need. Amgen has successfully implemented a hybrid CM process for a commercial lifecycle program. In this process, the bioreactor, harvest, capture column, and viral inactivation/depth filtration unit operations were integrated together in an automated, continuous module, while the remaining downstream unit operations took place in stand-alone batch mode. CM operations are particularly suited for so-called "high mix, low volume" manufacturing plants, where a variety of molecules are manufactured in relatively low volumes. The selected molecule fit this mold and was manufactured in a low-capital micro-footprint suite attached to an existing therapeutic production facility. Use of a hybrid process within an already operating facility required less capital and minimized complexity. To enable this hybrid CM process, an established fed-batch process was converted to a perfusion process with continuous harvest. Development efforts included both process changes and the generation of a novel cell line adapted to long-term perfusion. Chromatography resins were updated, and purification processes adapted to handle variable inputs due to the fluctuations in harvest titer from the lengthy production process. A novel automated single-use (SU) viral inactivation (VI) skid was introduced, which entailed the development of a robust pH verification and alarm system, along with procedures for product isolation to allow discard of specific cycles. The CM process demonstrated consistent performance, meaning it met predefined performance criteria (including product quality attributes, or PQAs) when operated within established process parameters and manufactured according to applicable procedures. Using a 75% reduction in scale, it resulted in a five-fold reduction in process media and buffer usage, a fifteen-fold increase in mass per thaw, and an overall process productivity increase of 45-fold (as measured by grams drug substance per liter per day.) The hybrid CM process also enabled increased material demand to be met with no change in cost of goods manufactured or plant capacity, due to the repurposing of existing facility space and the flexible duration of the hybrid CM harvest. Overall, the success of the hybrid CM platform represents an exciting opportunity to reduce costs and increase process efficiency in industry.

BVI-VFI: A Video Quality Database for Video Frame Interpolation.

Video frame interpolation (VFI) is a fundamental research topic in video processing, which is currently attracting increased attention across the research community. While the development of more advanced VFI algorithms has been extensively researched, there remains little understanding of how humans perceive the quality of interpolated content and how well existing objective quality assessment methods perform when measuring the perceived quality. In order to narrow this research gap, we have developed a new video quality database named BVI-VFI, which contains 540 distorted sequences generated by applying five commonly used VFI algorithms to 36 diverse source videos with various spatial resolutions and frame rates. We collected more than 10,800 quality ratings for these videos through a large scale subjective study involving 189 human subjects. Based on the collected subjective scores, we further analysed the influence of VFI algorithms and frame rates on the perceptual quality of interpolated videos. Moreover, we benchmarked the performance of 33 classic and state-of-the-art objective image/video quality metrics on the new database, and demonstrated the urgent requirement for more accurate bespoke quality assessment methods for VFI. To facilitate further research in this area, we have made BVI-VFI publicly available at https://github.com/danier97/BVI-VFI-database.

Outcomes of Venovenous Extracorporeal Membrane Oxygenation in Viral Acute Respiratory Distress Syndrome.

Our study assessed the relationship between the duration of venovenous extracorporeal membrane oxygenation (V-V ECMO) and patient outcomes. We studied patients undergoing V-V ECMO support for acute respiratory distress syndrome (ARDS) between 2009 and 2017 who were reported to the Extracorporeal Life Support Organization registry. We evaluated survival, major bleeding, renal failure, pulmonary complications, mechanical complications, neurologic complications, infection, and duration of V-V ECMO support. Multivariable regression modeling assessed risk factors for adverse events. Of the 4,636 patients studied, the mean support duration was 12.2 ± 13.7 days. There was a progressive increase in survival after the initiation of V-VECMO, peaking at a survival rate of 73% at 10 days of support. However, a single-day increase in V-V ECMO duration was associated with increased bleeding events (odds ratio [OR] 1.038; 95% confidence interval [CI]: 1.029-1.047; p < 0.0001), renal failure (OR 1.018; 95% CI: 1.010-1.027; p < 0.0001), mechanical complications (OR 1.065; 95% CI: 1.053-1.076; p < 0.0001), pulmonary complications (OR 1.04; 95% CI: 1.03-1.05; p < 0.0001), and infection (OR 1.04; 95% CI: 1.03-1.05; p < 0.0001). V-V ECMO progressively increases survival for ARDS over the first 10 days of support. Thereafter, rising complications associated with prolonged durations of support result in a progressive decline in survival.

The Potential of Topoisomerase Inhibitor-Based Antibody-Drug Conjugates.

DNA topoisomerases are essential enzymes that stabilize DNA supercoiling and resolve entanglements. Topoisomerase inhibitors have been widely used as anti-cancer drugs for the past 20 years. Due to their selectivity as topoisomerase I (TOP1) inhibitors that trap TOP1 cleavage complexes, camptothecin and its derivatives are promising anti-cancer drugs. To increase accumulation of TOP1 inhibitors in cancer cells through the targeting of tumors, TOP1 inhibitor antibody-drug conjugates (TOP1-ADC) have been developed and marketed. Some TOP1-ADCs have shown enhanced therapeutic efficacy compared to prototypical anti-cancer ADCs, such as T-DM1. Here, we review various types of camptothecin-based TOP1 inhibitors and recent developments in TOP1-ADCs. We then propose key points for the design and construction of TOP1-ADCs. Finally, we discuss promising combinatorial strategies, including newly developed approaches to maximizing the therapeutic potential of TOP1-ADCs.

Five-meter walk test before transcatheter aortic valve replacement and 1-year noncardiac mortality.

Objective: The purpose of this study is to assess whether the 5-m walk test is associated with 1-year mortality after transcatheter aortic valve replacement. Methods: Included in the analysis were 304 patients who received the 5-m walk test and underwent transcatheter aortic valve replacement from September 2012 to March 2019. They were classified into 3 groups based on their test score: ≤7, >7, and unable to walk. Preprocedure characteristics, postprocedure outcomes, and follow-up outcomes were compared between the groups. Results: For the 5-m walk test, 145 had a score ≤7 (Group N), 111 had a score >7 (Group S), and 48 were unable to walk (Group I). Average age in years was 80.2 ± 8.7 years in Group N, 81.2 ± 9.4 years in Group S, and 79.4 ± 9.2 in Group I (P = .23). The aortic valve mean gradient at discharge was 9.5 ± 4.1 mm Hg in Group N, 10.4 ± 5.5 mm Hg in Group S, and 8.2 ± 4.2 mm Hg in Group I (P = .05). The discharge survival was 97.2% in Group N, 96.4% in Group S, and 95.8% in Group I (P = .76). One-year survival was 92.8% in Group N, 84.1% in Group S, and 75% in Group I (P < .01) after adjusting for preprocedure characteristics. Noncardiac death was 5.1% in Group N, 13.1% in Group S, and 22.7% in Group I (P = .03). This indicates that the 5-m walk test was a risk factor for 1-year mortality. More specifically, a poor 5-m walk test score was associated with 1-year noncardiac mortality. Conclusions: The 5-m walk test score before transcatheter aortic valve replacement was associated with 1-year mortality, especially noncardiac mortality. It may help identify patients at high risk for 1-year mortality.

AZD2014, a dual mTOR inhibitor, attenuates cardiac hypertrophy in vitro and in vivo.

Cardiac hypertrophy is one of the most common genetic heart disorders and considered a risk factor for cardiac morbidity and mortality. The mammalian target of rapamycin (mTOR) pathway plays a key regulatory function in cardiovascular physiology and pathology in hypertrophy. AZD2014 is a small-molecule ATP competitive mTOR inhibitor working on both mTORC1 and mTORC2 complexes. Little is known about the therapeutic effects of AZD2014 in cardiac hypertrophy and its underlying mechanism. Here, AZD2014 is examined in in vitro model of phenylephrine (PE)-induced human cardiomyocyte hypertrophy and a myosin-binding protein-C (Mybpc3)-targeted knockout (KO) mouse model of cardiac hypertrophy. Our results demonstrate that cardiomyocytes treated with AZD2014 retain the normal phenotype and AZD2014 attenuates cardiac hypertrophy in the Mybpc3-KO mouse model through inhibition of dual mTORC1 and mTORC2, which in turn results in the down-regulation of the Akt/mTOR signaling pathway.

Peptide Adjuvant to Invigorate Cytolytic Activity of NK Cells in an Obese Mouse Cancer Model.

Cancer patients who are overweight compared to those with normal body weight have obesity-associated alterations of natural killer (NK) cells, characterized by poor cytotoxicity, slow proliferation, and inadequate anti-cancer activity. Concomitantly, prohibitin overexpressed by cancer cells elevates glucose metabolism, rendering the tumor microenvironment (TME) more tumor-favorable, and leading to malfunction of immune cells present in the TME. These changes cause vicious cycles of tumor growth. Adoptive immunotherapy has emerged as a promising option for cancer patients; however, obesity-related alterations in the TME allow the tumor to bypass immune surveillance and to down-regulate the activity of adoptively transferred NK cells. We hypothesized that inhibiting the prohibitin signaling pathway in an obese model would reduce glucose metabolism of cancer cells, thereby changing the TME to a pro-immune microenvironment and restoring the cytolytic activity of NK cells. Priming tumor cells with an inhibitory the prohibitin-binding peptide (PBP) enhances cytokine secretion and augments the cytolytic activity of adoptively transferred NK cells. NK cells harvested from the PBP-primed tumors exhibit multiple markers associated with the effector function of active NK cells. Our findings suggest that PBP has the potential as an adjuvant to enhance the cytolytic activity of adoptively transferred NK cells in cancer patients with obesity.

Targeted delivery of heat shock protein 90 inhibitors prevents growth of HER2-positive tumor.

Heat shock protein 90 (HSP90) plays a crucial role in the survival of cancer cells. When an inhibitor blocks the signaling pathway of HSP90, its client proteins are degraded, destabilized, and inactivated. Although HSP90 inhibitors are in various clinical trials, there are no HSP90 inhibitor-immunoconjugates due to the difficulty in chemical modification of HSP90 inhibitors. Here we show that biological affinity binding enables the incorporation of HSP90 inhibitors to an antibody without the need for chemical conjugation. We constructed a recombinant fusion protein composed of an anti-HER2 scFv and an HSP90 inhibitor-binding domain (HER2 scFv-HBD). The HBD spontaneously captures a HSP90 inhibitor, resulting in the formation of an HER2 scFv-HBD/HSP90 inhibitor complex. In an HER2-positive cancer mouse model, targeted delivery of HSP90 inhibitors was confirmed and improved anti-cancer efficacy was observed. We have proven the promise of tumor-directed HSP90 inhibition as a new form of targeted therapy.

Short-Term Risk of Bilateral Internal Mammary Artery Grafting in Diabetic Patients.

This study compares the morbidity and mortality at 30 days following the use of bilateral internal mammary arteries (BIMA) vs a single internal mammary artery (SIMA) at the time of coronary artery bypass grafting (CABG) in patients with a preoperative HbA1c. Patients undergoing CABG from January 2008 to December 2016 reported to the Society of Thoracic Surgeons database were retrospectively reviewed. The patients were divided into 2 groups: use of BIMA or use of SIMA and propensity matched. To assess the effect of preoperative HbA1c, both groups were further divided into 5 subgroups: patients without diabetes mellitus (DM), or patients with DM and a preoperative HbA1c level in one of four groups (< 7%, 7-9%, 9-11%, or >11%). The postoperative outcomes in both the BIMA and SIMA groups were compared. There were 700,504 and 28,115 patients with measured preoperative HbA1c levels in the SIMA and BIMA groups, respectively. Propensity score matching identified 23,635 comparable patients in each group for analysis. There was no difference in postoperative mortality between the BIMA and SIMA groups (1.3% vs 1.2%). The incidences of sternal wound infection (SWI) in patients undergoing placement of BIMA vs SIMA were: 0.8% vs 0.4% with no DM (P < 0.0001), 1.9% vs 1.0% with HbA1c < 7% (P < 0.001), 2.4% vs 1.2% with HbA1c 7-9% (P < 0.001), 2.8% vs 1.4% with HbA1c 9-11% (P = 0.02), 4.1% vs 1.5% with HbA1c > 11% (P = 0.01). Based on the incidence of SWI, BIMA is a reasonable approach with an HbA1c<7%.

Simvastatin Treatment Does Not Ameliorate Muscle Pathophysiology in a Mouse Model for Duchenne Muscular Dystrophy.

Duchenne muscular dystrophy is an X-linked, recessive muscular dystrophy in which the absence of the dystrophin protein leads to fibrosis, inflammation and oxidative stress, resulting in loss of muscle tissue. Drug repurposing, i.e. using drugs already approved for other disorders, is attractive as it decreases development time. Recent studies suggested that simvastatin, a cholesterol lowering drug used for cardiovascular diseases, has beneficial effects on several parameters in mdx mice. To validate properly the effectiveness of simvastatin, two independent labs tested the effects of 12-week simvastatin treatment in either young (starting at 4 weeks of age) or adult (starting at 12 weeks of age) mdx mice. In neither study were benefits of simvastatin treatment observed on muscle function, histology or expression of genes involved in fibrosis, regeneration, oxidative stress and autophagy. Unexpectedly, although the treatment protocol was similar, simvastatin plasma levels were found to be much lower than observed in a previous study. In conclusion, in two laboratories, simvastatin did not ameliorate disease pathology in mdx mice, which could either be due to the ineffectiveness of simvastatin itself or due to the low simvastatin plasma levels following oral administration via the food.

Characterizing the spatiotemporal envelope of the human visual system through the visibility of temporal aliasing artifacts.

Previous studies have demonstrated that the onset of temporal aliasing artifacts occurs when the spatial displacement between samples reaches a critical distance, and that subsequently a linear relationship exists between stimulus speed and critical sampling rates. In this paper, we carry out further experimentation using a novel experimental setup, in which a strobe light is used to emulate impulsive temporal sampling, in order to investigate the spatiotemporal envelope of the human visual system and the effect of a stimulus. For non-periodic stimuli, experimental results show that critical sampling rates increase with motion speed and decrease with stimulus width. These interactions can be described using simple log-linear models, and characterized using the temporal aliasing visibility function, where maximum critical frame rates up to 1500 Hz are predicted. For periodic stimuli, we demonstrate that both perceptible temporal aliasing artifacts and stimulus aliasing can cause stroboscopic effects.

The Effect of Container Surface Passivation on Aggregation of Intravenous Immunoglobulin Induced by Mechanical Shock.

Aggregation of therapeutic proteins can result from a number of stress conditions encountered during their manufacture, transportation, and storage. This work shows the effects of two interrelated sources of protein aggregation: the chemistry and structure of the surface of the container in which the protein is stored, and mechanical shocks that may result from handling of the formulation. How different mechanical stress conditions (dropping, tumbling, and agitation) and container surface passivation affect the stability of solutions of intravenous immunoglobulin are investigated. Application of mechanical shock causes cavitation to occur in the protein solution, followed by bubble collapse and the formation of high-velocity fluid microjets that impinged on container surfaces, leading to particle formation. Cavitation was observed after dropping of vials from heights as low as 5 cm, but polyethylene glycol (PEG) grafting provided temporary protection against drop-induced cavitation. PEG treatment of the vial surface reduced the formation of protein aggregates after repeated dropping events, most likely by reducing protein adsorption to container surfaces. These studies enable the development of new coatings and surface chemistries that can reduce the particulate formation induced by surface adsorption and/or mechanical shock.

Flocculation behavior and mechanisms of block copolymer architectures on silica microparticle and Chlorella vulgaris systems.

HYPOTHESIS: Flocculation performance using polyelectrolytes is influenced by critical design parameters including molecular weight, amount and sign of the ionic charge, and polymer architecture. It is expected that systematic variation of these characteristics will impact not only flocculation efficiency (FE) achieved but that charge density and architecture, specifically, can alter the flocculation mechanism. Therefore, it should be possible to tune these design parameters for a desired flocculation application. EXPERIMENTS: Cationic-neutral and polyampholytic copolymers, exhibiting a range of molecular weights (103-106 g/mol), varying charge levels (0-100% cationic, neutral and anionic), and random or block copolymer architecture, were applied to dilute suspensions of silica microparticles (control) and Chlorella vulgaris. FE and zeta potential values were determined over a range of flocculant doses to evaluate effectiveness and mechanism achieved. FINDINGS: These different classes of copolymers provide specific benefits for flocculation, with many achieving >95% flocculation. Block copolymer flocculants exhibit a proposed, dominant bridging mechanism, therefore reducing flocculant dosage required for effective flocculation when compared to analogous random copolymer flocculants. Polyampholytic copolymers applied to C. vulgaris generally exhibited a bridging mechanism and increased FE compared to equivalent cationic-neutral copolymers, indicating a benefit of the anionic component on a more, complex, diversely charged suspension.

The Role of Adjuvant Therapy in Advanced Thymic Carcinoma: A National Cancer Database Analysis.

BACKGROUND: There is area of controversy and variability in the recommendation for the role of adjuvant therapy after R0 resection of a Masaoka stage IIB and III thymic carcinoma. This study investigated the role of adjuvant therapy in patients who had complete surgical resection for thymic carcinoma. METHODS: Patients with stage IIB and III thymic carcinoma who underwent curative resection were queried and categorized according to Masaoka-Koga stage groups from the National Cancer Database. Patients were grouped by treatment status (surgery only or surgery followed by adjuvant therapy). Kaplan-Meier estimates of overall survival and univariate and multivariate Cox proportional hazards regression analyses were performed. RESULTS: From 2004 to 2013, 632 surgical patients with stage IIB and III thymic carcinoma were selected for analysis. In stage IIB patients, the adjuvant therapy group had improved survival compared with the surgery only group (P = .01), although no survival difference was observed in patients who had R0 resection between the 2 groups (P = .59). In multivariate analysis, age (P < .001) and grade III and IV (P = .02) negatively impacted survival; the adjuvant therapy improved survival (P < .02). For stage III cancer, the adjuvant therapy group had improved survival compared with the OS group regardless of margin status. In multivariate analysis, tumor size exceeding 70 mm (P = .02) and positive margin (P < .01) negatively affected survival; adjuvant therapy improved survival (P < .01). CONCLUSIONS: Adjuvant therapy showed no benefit in patients with stage IIB cancer who had R0 resection. Use of adjuvant therapy should be strongly considered for stage IIB cancer patients with positive margins and all stage III thymic cancer patients.

Surface-Templated Nanobubbles Protect Proteins from Surface-Mediated Denaturation.

In this Letter, we report that surface-bound nanobubbles reduce protein denaturation on methylated glass by irreversible protein shell formation. Single-molecule total internal reflection fluorescence (SM-TIRF) microscopy was combined with intramolecular Förster resonance energy transfer (FRET) to study the conformational dynamics of nitroreductase (NfsB) on nanobubble-laden methylated glass surfaces, using reflection brightfield microscopy to register nanobubble locations with NfsB adsorption. First, NfsB adsorbed irreversibly to nanobubbles with no apparent desorption after 5 h. Moreover, virtually all (96%) of the NfsB molecules that interacted with nanobubbles remained folded, whereas less than 50% of NfsB molecules remained folded in the absence of nanobubbles on unmodified silica or methylated glass surfaces. This trend was confirmed by ensemble-average fluorometer TIRF experiments. We hypothesize that nanobubbles reduce protein damage by passivating strongly denaturing topographical surface defects. Thus, nanobubble stabilization on surfaces may have important implications for antifouling surfaces and improving therapeutic protein storage.

Imaging assessment of cardioprotection mediated by a dodecafluoropentane oxygen-carrier administered during myocardial infarction.

INTRODUCTION: The objective of this study was to investigate the cardioprotective effects of a dodecafluoropentane (DDFP)-based perfluorocarbon emulsion (DDFPe) as an artificial carrier for oxygen delivery to ischemic myocardium, using 99mTc-duramycin SPECT imaging. METHODS: Rat hearts with Ischemia-reperfusion (I/R) was prepared by coronary ligation for 45-min followed by reperfusion. The feasibility of 99mTc-duramycin in detecting myocardial I/R injury and its kinetic profile were first verified in the ischemic hearts with 2-h reperfusion (n = 6). DDFPe (0.6 mL/kg) was intravenously administered at 10 min after coronary ligation in fifteen rats and saline was given in thirteen rats as controls. 99mTc-duramycin SPECT images were acquired in the DDFPe-treated hearts and saline controls at 2-h (DDFPe-2 h, n = 7 and Saline-2 h, n = 6) or 24-h (DDFPe-24 h, n = 8 and Saline-24 h, n = 7) of reperfusion. RESULTS: SPECT images, showing "hot-spot" 99mTc-duramycin uptake in the ischemic myocardium, exhibited significantly lower radioactive retention and smaller hot-spot size in the DDFPe-2 h and DDFPe-24 h hearts compared to controls. The infarcts in the Saline-24 h hearts extended significantly relative to measurements in the Saline-2 h. The extension of infarct size did not reach a statistical difference between the DDFPe-2 h and DDFPe-24 h hearts. Ex vivo measurement of 99mTc-duramycin activity (%ID/g) was lower in the ischemic area of DDFPe-2 h and DDFPe-24 h than that of the Saline-2 h and Saline-24 h hearts (P < 0.05). The area of injured myocardium, delineated by the uptake of 99mTc-duramycin, extended more substantially outside the infarct zone in the controls. CONCLUSIONS: Significant reduction in myocardial I/R injury, as assessed by 99mTc-duramycin cell death imaging and histopathological analysis, was induced by DDFPe treatment after acute myocardial ischemia. 99mTc-duramycin imaging can reveal myocardial cell death in ischemic hearts and may provide a tool for the non-invasive assessment of cardioprotective interventions.

Is There a Role for Cancer-Directed Surgery in Early-Stage Sarcomatoid or Biphasic Mesothelioma?

BACKGROUND: Benefits of surgical resection for early-stage nonepithelioid malignant pleural mesothelioma (MPM) have not been clearly elucidated. This study investigated whether cancer-directed surgery affects overall survival compared with nonsurgical therapies for T1-T2 N0 M0 sarcomatoid or biphasic MPM patients. METHODS: Adult patients with clinical stage I or II MPM were identified in the National Cancer Database from 2004 to 2103. Patients who underwent cancer-directed surgery were matched by propensity score with patients who had received chemotherapy/radiotherapy or no treatments. Overall survival was compared using a Cox proportional hazard regression model. RESULTS: From National Cancer Database queries, 878 patients with clinical stage I or II MPM with sarcomatoid (n = 524) or biphasic (n = 354) histology were identified. Overall median survival was 5.5 months for patients with sarcomatoid mesothelioma. The cancer-directed surgery improved overall survival compared with no operation (median survival, 7.56 months vs 4.21 months, respectively; p < 0.01). In the biphasic group, median overall survival was 12.2 months. Again, the cancer-directed surgery improved survival compared with no operation (15.8 months vs 9.3 months, p < 0.01). For both histologies, the cancer-directed surgery improved overall survival compared with those who underwent chemotherapy or radiotherapy, or both, without resection (p < 0.05). Perioperative mortality was 6.0% at 30 days and 21.4% at 90 days. CONCLUSIONS: The cancer-directed surgery is associated with improved survival in early-stage MPM patients with nonepithelioid histology compared with those who did not undergo resection or chose medical therapy. Given the high perioperative mortality, a careful patient selection and multidisciplinary evaluation is recommended.

Cell surface engineering and application in cell delivery to heart diseases.

Cell-based therapy has expanded its influence in cancer immunotherapy, regenerative medicine, and tissue engineering. Due to their secretory functions, differentiation capabilities, specific homing effects through chemotaxis, distinctive therapeutic potentials, and ex vivo expandability, cells have become an attractive reagent for advanced therapeutic strategies. Therefore, the ability to modify cells and manipulate their functions according to intended therapeutic designs has been the central scientific interest in the field of biomedical research. Many innovative methods have been developed with genetic modification of cells being the most advanced cell surface engineering technique. Although genetic modification is a powerful tool, it has a limited applicability due to the permanent modifications made on cells. Alternatively, many endeavors have been made to develop surface engineering techniques that can circumvent the limitations of genetic modification. In this review, current methods of non-genetic cell surface modification, including chemical conjugations, polymeric encapsulation, hydrophobic insertion, enzymatic and metabolic addition, will be introduced. Moreover, cell surface engineering plausible for cardiac remodeling and the future prospective will be discussed at the end.