Engineering of the PETNR active site to accommodate novel α/β substituted enone substrates

Experiments facilitating the engineering of the PETNR active site to accommodate a range of non natural enone substrates with substituents localised on the α and β carbons of the unsaturated bond are described. In order to facilitate the high throughput purification of PETNR libraries poly histidine (PETNRHis) and biotin (PETNRBio) tagged PETNR variants were generated. High throughput protocols were developed for the automated generation, purification and screening of libraries in a 96 well format. Protocols were optimised and trialled using blocks consisting of PETNRHis WT only and characterised in terms of intra block variation. A range of single site saturation mutagenic libraries were generated at positions in the active site consisting of T26, Y68, W102, H181, H184, Y186, Q241 and Y351. Sequencing results indicated randomised libraries with the occasional instance of bias evident. Expression and purification in a 96 well format was monitored by SDS PAGE and protein quantitation. Library activity was quantified and demonstrated to retain varying degrees of activity with the model substrate 2-cyclohexenone. Following this verification of the experimental protocol libraries were screened against a range of substrates analogous to substrates demonstrated to be active with PETNRWT but incorporating substituents at the α and β carbons. 'Hits' generated from these screening reactions were studied further by the determination of the specific activity and quantitation of substrate/product from biotransformation reactions. From these screening experiments totalling 3,600 individual reactions, 35 were identified as potential hits, of these 8 proved to be genuinely improved variants. Substituents at the β carbon were demonstrated to compromise the activity of the WT enzyme most severely. Positions 68, 102, and 351 were demonstrated to play an important role in the accommodation of substituents at the α carbon whilst residues 26 and 351 are important for the β carbon. The best variants demonstrated up to 9 fold improvements in poor substrates which represented rates in excess of those observed for model substrates.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Process economics evaluation of Adeno-associated Viral Vector (AAV) manufacturing

With two products currently approved for gene therapy purposes, adeno-associated virus (AAV) manufacturing has seen consistent pressure to develop scalable strategies, particularly during cell culture and purification. Traditionally, cell culture in adherent mode and gradient density-based polishing steps have been adopted for AAV processing. However, these technologies rely on scale-out strategies to increase capacity in a commercial environment, thereby incurring large costs and facility footprints. This presentation presents insights from an advanced economics analysis using a decisional tool developed at UCL to identify the most cost-effective route for large-scale manufacture of AAV. A cost of goods (COG) comparison will be presented between adherent and suspension cell culture, as well as anion-exchange chromatography versus batch ultracentrifugation at the base case. This provides benchmark COG values, the savings that can be achieved moving to more scalable technologies and the contributions of materials, labour, QC and facility-related costs. A stochastic cost comparison is used to reveal the impact of key input uncertainties (e.g. productivities) on the robustness of each strategy and the likelihood of achieving target COG values. Next, the case study looks at a broad range of USP (e.g. multi-layer cell factories, fixed-bed reactor, single-use stirred tank bioreactor) and DSP (e.g. packed-bed chromatography, batch and continuous ultracentrifugation) technology options and uses an optimisation algorithm to identify the optimal flowsheet for AAV manufacture in terms of both cost-effectiveness and meeting purity targets. This analysis highlights how the optimal flowsheet will change depending on the purity target that needs to be met, with specific focus upon HCPs, DNA and empty capsids Finally, the presentation will highlight how the optimal solutions change for different combinations of demand, batch size and AEX yield, highlighting the trade-off between achieving high yields and purities, whilst opting for scalable technologies. These insights help make better decisions early on in development to facilitate successful commercialisation

Process economics evaluation and optimization of adeno-associated virus downstream processing

Adeno-associated virus (AAV) manufacturing has traditionally focused upon lab-scale techniques to culture and purify vector products, leading to limitations in production capacity. The tool presented in this paper assesses the feasibility of using non-scalable technologies at high AAV demands and identifies optimal flowsheets at large-scale that meet both cost and purity targets. The decisional tool comprises (a) a detailed process economics model with the relevant mass balance, sizing, and costing equations for AAV upstream and downstream technologies, (b) a built-in Monte Carlo simulation to assess uncertainties, and (c) a brute-force optimization algorithm for rapid investigation into the optimal purification combinations. The results overall highlighted that switching to more scalable upstream and downstream processing alternatives is economically advantageous. The base case analysis showed the cost and robustness advantages of utilizing suspension cell culture over adherent, as well as a fully chromatographic purification platform over batch ultracentrifugation. Expanding the set of purification options available gave insights into the optimal combination to satisfy both cost and purity targets. As the purity target increased, the optimal polishing solution moved from the non-capsid purifying multimodal chromatography to anion-exchange chromatography or continuous ultracentrifugation

Continuous integrated biologics manufacturing

Biosimilars and patent expiry are forcing the biopharma industry to find new ways to maintain competitiveness by ensuring affordability, quality, and delivery performance. Despite great improvements in upstream processing (USP) efficiency, higher titres create downstream processing (DSP) bottlenecks and facility fit issues: Equipment reaches its physical and capacity limits thereby increasing processing time, material consumption and overall cost. Continuous processes have been proposed as a solution to many of these issues as they offer higher productivity while reducing cycle times, buffer/resin usage and required footprint. A consortium of UK based biopharmaceutical companies, suppliers and not for profit research organisations, funded by an Innovate UK grant, has been created and will investigate how such an integrated, continuous downstream process system can be realised. The system has been constructed and is currently operating at the Centre for Process Innovation at Darlington, UK. The project combines and condenses multiple DSP unit operations to function as one uninterrupted system with integrated analytics and overarching automated control. The aim is to create an operationally-efficient, multi-product platform which replicates the functionality of a larger plant processing 100 L feedstock per day (independent of product titre). The integrated unit will be tested on several biologic processes demonstrating the system’s potential to enable product changeover, increased facility flexibility and productivity. Significant focus will be given to process validation procedures and the use of low level control to achieve process stability (steady state) and maintain acceptable product quality. This work will lay the foundation for real-time release strategies and replace drug substance release testing. This presentation will provide an overview of the project and show recently-acquired data from the automated purification of industry-relevant monoclonal antibodies. In doing so, this will highlight the applicability and demonstrate the real-world potential for integrated continuous processing to advance the manufacturing of biopharmaceuticals

Developing a flexible automated continuous downstream processing system for research to clinical supply

Continuous manufacturing has gained a lot of attention over the last 10-15 years for numerous reasons such as the potential for higher efficiencies, reduced cost of goods, and improved product quality. However, the adoption of these technologies has been slow due to concerns over operating these processes in a GMP manufacturing environment. Some of these concerns relate to the operation of multiple continuous unit operations in an integrated process sequence. This presentation will highlight these concerns and show how these issues were addressed by developing an overarching automated and modular platform which can be easily adapted for processing most products. The developed automation platform is the result of a project funded by Innovate UK that brings together a number of biopharmaceutical companies including Allergan, AstraZeneca, Fujifilm Diosynth Biotechnologies and GSK to identify and address these issues. One objective of the project is to develop a flexible automated biologics downstream process consisting of multiple unit operations that can be rapidly reconfigured for manufacturing different products. To that end the process has been design with modularity in mind with each module having common inputs and outputs. The automation software has also been developed in a way that most typical downstream processes can be implemented in the system with little to no software updates. The ability to rapidly reconfigure the process has been demonstrated by using the system to produce two products with different process sequences. Another issue that inhibits the adoption of continuous technologies is the concern over simultaneously operating multiple unit operations. This presentation will detail how the automation software was developed to control both the key unit operations such as chromatography and filtration steps but also intermediate operations such as feed conditioning and viral inactivation steps. The automated system reduces the complexity of downstream processes, which can have in excess of eleven unit operations, to a single user-friendly interface. Implementing this control platform enables a single operator to control the entire process. This presentation will also detail how the automation strategy has been developed to enable a single operator to deal with start-up/shutdown, perturbations in the process and mid-process equipment turnover. It will highlight the challenges that have been faced when developing this system and how these have been overcome. The aim of this project was to improve efficiency by reducing processing time when compared to the current batch process and this was demonstrated by testing the system with two different products (a MAb and a MAb fusion protein). Furthermore, this presentation with show data from the production of these two products that demonstrates comparability between the continuous process and the original batch processes

Developing a flexible automated continuous downstream processing system for research to clinical supply

Continuous manufacturing has gained a lot of attention over the last 10-15 years for numerous reasons such as the potential for higher efficiencies, reduced cost of goods, and improved product quality. However, the adoption of these technologies has been slow due to concerns over operating these processes in a GMP manufacturing environment. Some of these concerns relate to the operation of multiple continuous unit operations in an integrated process sequence. This presentation will highlight these concerns and show how these issues were addressed by developing an overarching automated and modular platform which can be easily reconfigured for processing most products. The developed automation platform is the result of a project funded by Innovate UK that brings together a number of biopharmaceutical companies including Allergan, AstraZeneca, Fujifilm Diosynth Biotechnologies and GSK to identify and address these issues. One objective of the project is to develop a flexible automated biologics downstream process consisting of multiple unit operations that can be rapidly reconfigured for manufacturing different products. To that end the process has been design with modularity in mind with each module having common inputs and outputs. The automation software has also been developed in a way that most typical downstream processes can be implemented in the system with little to no software updates. The ability to rapidly reconfigure the process has been demonstrated by using the system to produce three products with different process sequences. Another issue that inhibits the adoption of continuous technologies is the concern over simultaneously operating multiple unit operations. This presentation will detail how the automation software was developed to control both the key unit operations such as chromatography and filtration steps but also intermediate operations such as feed conditioning and viral inactivation steps. The automated system reduces the complexity of downstream processes, which can have in excess of eleven unit operations, to a single user-friendly interface. Implementing this control platform enables a single operator to control the entire process. This presentation will also detail how the automation strategy has been developed to enable a single operator to deal with start-up/shutdown, perturbations in the process and mid-process equipment turnover. It will highlight the challenges that have been faced when developing this system and how these have been overcome. The aim of this project was to improve efficiency by reducing processing time when compared to the current batch process and this was demonstrated by testing the system with three different products (a MAb and a MAb fusion protein). Furthermore, this presentation with show data from the production of three products that demonstrates comparability between the continuous process and the original batch processes. It will then detail how this was used to demonstrate the production of a large-scale clinical batch run

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Process optimization for adenovirus-based viral vector vaccines

With two products currently approved for gene therapy purposes, adeno-associated virus (AAV) manufacturing has seen consistent pressure to develop scalable strategies, particularly during cell culture and purification. Traditionally, cell culture in adherent mode and gradient density-based polishing steps have been adopted for AAV processing. However, these technologies rely on scale-out strategies to increase capacity in a commercial environment, thereby incurring large costs and facility footprints. This presentation presents insights from an advanced economics analysis using a decisional tool developed at UCL to identify the most cost-effective route for large-scale manufacture of AAV. A cost of goods (COG) comparison will be presented between adherent and suspension cell culture, as well as anion-exchange chromatography versus batch ultracentrifugation at the base case. This provides benchmark COG values, the savings that can be achieved moving to more scalable technologies and the contributions of materials, labour, QC and facility-related costs. A stochastic cost comparison is used to reveal the impact of key input uncertainties (e.g. productivities) on the robustness of each strategy and the likelihood of achieving target COG values. Next, the case study looks at a broad range of USP (e.g. multi-layer cell factories, fixed-bed reactor, single-use stirred tank bioreactor) and DSP (e.g. packed-bed chromatography, batch and continuous ultracentrifugation) technology options and uses an optimisation algorithm to identify the optimal flowsheet for AAV manufacture in terms of both cost-effectiveness and meeting purity targets. This analysis highlights how the optimal flowsheet will change depending on the purity target that needs to be met, with specific focus upon HCPs, DNA and empty capsids Finally, the presentation will highlight how the optimal solutions change for different combinations of demand, batch size and AEX yield, highlighting the trade-off between achieving high yields and purities, whilst opting for scalable technologies. These insights help make better decisions early on in development to facilitate successful commercialisation