Monoclonal Antibodies Production Platforms: An Opportunity Study of a Non-Protein-A Chromatographic Platform Based on Process Economics

Biparatopic Nanobody-Based Immunosorbent for the Highly Selective Elimination of Tumor Necrosis Factor-α

Removing the overexpressed TNF-α by hemoperfusion positively affects clinical treatments for diseases such as autoimmune disease and sepsis. However, clearance ratios of adsorbents targeting TNF-α were limited by the extremely low concentration of TNF-α (mostly <1000 ng/L in sepsis) and hydrophobic interactions. In this work, biparatopic nanobodies (NbC21) with a high affinity of 19.9 pM, which bind to two distinct sites of TNF-α, were constructed as high-affinity ligands for the immunosorbent. The theoretical maximum adsorption capacity estimated from the Langmuir isotherm was up to 18.22 mg/g gel. The prepared immunosorbent (NbC21-sorbent) had an outstanding TNF-α clearance ratio of approximately 96% during the dynamic adsorption test, with a sorbent-to-serum ratio of 1:1000. Additionally, it demonstrated favorable hemocompatibility and a prolonged storage capability. The results indicated that the biparatopic nanobody immunosorbent exhibited significant potential for clinical applications as it met the stringent criteria for both efficacy and safety.

Surrogate-based Optimization of Capture Chromatography Platforms for the Improvement of Computational Efficiency

In this work, we discuss the use of surrogate functions and a new optimization framework to create an efficient and robust computational framework for process design. Our model process is the capture chromatography unit operation for monoclonal antibody purification, an important step in biopharmaceutical manufacturing. Simulating this unit operation involves solving a system of non-linear partial differential equations, which can have high computational cost. We implemented surrogate functions to reduce the computational time and make the framework more attractive for industrial applications. This strategy yielded accurate results with a 93% decrease in processing time. Additionally, we developed a new optimization framework to reduce the number of simulations needed to generate a solution to the optimization problem. We demonstrate the performance of our new framework, which uses MATLAB built-in tools, by comparing its performance against individual optimization algorithms for problems with integer, continuous, and mixed-integer variables.

Computational framework for the techno-economic analysis of monoclonal antibody capture chromatography platforms

We developed a computational framework that integrates commercial software components to perform customizable technoeconomic feasibility analyses. The use of multiple software packages overcomes the shortcomings of each to provide a detailed simulation that can be used for sensitivity analyses and optimizations. In this paper, the framework was used to evaluate the performance of monoclonal antibody capture processes. To this end, the simulation framework incorporated dynamic models for the affinity chromatography step that were validated with experimental breakthrough curves. The results were integrated with an Intelligen SuperPro Designer process simulation for the evaluation of key performance indicators of the operations. As proof of concept, the framework was used to perform a sensitivity analysis and optimization for a case study in which we sought to compare membrane and resin chromatography for disposable and reusable batch capture platforms. Two membranes and one resin were selected for the capture media, which yielded six process alternatives to compare. The objective functions were set to be cost of goods, process time, and buffer utilization. The results of the optimization of these process alternatives were a set of operating conditions that display tradeoffs between competing objectives. From this application exercise, we conclude that the framework can handle multiple variables and objectives, and it is adaptable to platforms with different chromatography media and operating modes. Additionally, the framework is capable of providing ad hoc analyses for decision making in a specific production context.

Design and economic investigation of a Multicolumn Countercurrent Solvent Gradient Purification unit for the separation of an industrially relevant PEGylated protein

Conjugation of biopharmaceuticals to polyethylene glycol chains, known as PEGylation, is nowadays an efficient and widely exploited strategy to improve critical properties of the active molecule, including stability, biodistribution profile, and reduced clearance. A crucial step in the manufacturing of PEGylated drugs is the purification. The reference process in industrial settings is single-column chromatography, which can meet the stringent purity requisites only at the expenses of poor product recoveries. A valuable solution to this trade-off is the Multicolumn Countercurrent Solvent Gradient Purification (MCSGP), which allows the internal and automated recycling of product-containing side fractions that are typically discarded in the batch processes. In this study, an ad hoc design procedure was applied to the single-column batch purification of an industrially relevant PEGylated protein, with the aim of defining optimal collection window, elution duration and elution buffer ionic strength to be then transferred to the MCSGP. This significantly alleviates the design of the continuous operation, subjected to manifold process parameters. The MCSGP designed by directly transferring the optimal parameters allowed to improve the yield and productivity by 8.2% and 17.8%, respectively, when compared to the corresponding optimized batch process, ensuring a purity specification of 98.0%. Once the efficacy of MCSGP was demonstrated, a detailed analysis of its cost of goods was performed and compared to the case of single-column purification. To the best of our knowledge, this is the first example of a detailed economic investigation of the MCSGP across different manufacturing scenarios and process cadences of industrial relevance, which demonstrated not only the viability of this continuous technology but also its flexibility.

SnoopLigase Enables Highly Efficient Generation of C-C-Linked Bispecific Nanobodies Targeting TNF-α and IL-17A

Bispecific antibodies (bis-Nbs) have been extensively developed since the concept was devised over the decades. Taking advantage of the superior characteristics of nanobodies, bis-Nbs exhibit an emerging tendency to become the new generation of research and diagnostic tools. Traditional strategies to connect the homo- or heterogeneous monomers are commonly applied, but there are still technical issues to generate the bispecific molecules as efficiently as designed. Here, we utilize SnoopLigase to directly tether the C terminus (C-C) of the tagged nanobodies against tumor necrosis factor-α (TNF-α) and interleukin-17A (IL-17A). Under optimal conditions, the yield of C-C-linked bis-Nbs can reach as high as 70% due to the existence of SnoopLigase. The prepared bis-Nbs possessed similar or even higher affinity as the monomers and significantly inhibited the proliferation and migration of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) induced by TNF-α and IL-17A. This study provides an innovative route for using SnoopLigase to realize a highly efficient generation of C-C-linked bis-Nbs. The approach can be applied to different and multicomponent systems for their potential applications in disease diagnosis and treatment.

Automation of Dead End Filtration: An Enabler for Continuous Processing of Biotherapeutics

Dead end filtration is a critical unit operation that is used for primary and secondary clarification during manufacturing of both microbial and mammalian cell based biotherapeutics. Dead end filtration is conventionally done in batch mode and requires filter pre-sizing using extensive scouting studies, along with filter over-sizing before deployment to handle potential variability. However, continuous manufacturing processes require consistent use of dead-end filtration over weeks or months, with potential unpredictable variations in feed stream attributes, which is a challenge currently facing the industry. In this work, a dead-end filtration skid is designed for continuous depth filtration, incorporating multiple small-sized filters along with turbidity, and pressure sensors with immediate switching to a fresh filter whenever turbidity or pressure breakthrough above a pre-determined cut-off is detected in real time. The skid has been successfully tested for manufacturing of granulocyte colony stimulating factor from Escherichia coli, human serum albumin from Pichia pastoris, and a monoclonal antibody therapeutic from CHO cells. The proposed skid can be directly applied for any dead-end filtration application with minimal prior scouting studies or sizing calculations for scale-up. It is a useful solution for continuous processing trains where the nature of the feed, such as its turbidity or host cell proteins content, may change over long continuous campaigns, rendering previous sizing calculations inaccurate. The skid also allows significant cost savings by eliminating the sizing safety factor of 1.5-2x which is generally added before filter deployment at manufacturing scale.

Mobile-Phase Modulators as Salt Tolerance Enhancers in Phenylboronate Chromatography: Thermodynamic Evaluation of the Mechanisms Underlying the Adsorption of Monoclonal Antibodies

Phenylboronate chromatography has been employed for bioseparation applications though details concerning the mechanisms of interaction between the ligand and macromolecules remain widely unknown. Here, the phenomena underlying the adsorption of an anti-human interleukin-8 (anti-IL8) monoclonal antibody (mAb) onto an m-aminophenylboronic acid (m-APBA) ligand in the presence of different mobile-phase modulators (NaF/MgCl ₂ /(NH ₄ ) ₂ SO ₄ ) and under different pH values (7.5/8.5/9.0) is investigated. Flow microcalorimetry (FMC) is applied to measure instantaneous heat energy transfer, providing insights about the role of specific and nonspecific interactions involved in the adsorptive process. Results show that the adsorption of anti-IL8 mAb to m-APBA is enthalpically driven, corroborating the presence of the reversible esterification reaction between boronic acid or boronates and cis-diol-containing molecules. Nevertheless, for all mobile-phase modulators studied, changes in thermogram profiles are observed as well as reductions in the net heat of adsorption when increasing the pH. Overall, FMC and parallel chromatographic experiments data suggest that ligand salt tolerance could be enhanced using mobile-phase modulators, with all salts studied promoting the specific cis-diol interactions and reducing nonspecific interactions. The last feature is more noticeable at pH values above ligand's pK _a , mainly due to the ability of NaF and (NH ₄ ) ₂ SO ₄ to diminish electrostatic interactions when compared to the commonly used NaCl.

Optimization of Vapor Diffusion Conditions for Anti-CD20 Crystallization and Scale-Up to Meso Batch

The crystal form is one of the preferred formulations for biotherapeutics, especially thanks to its ability to ensure high stability of the active ingredient. In addition, crystallization allows the recovery of a very pure drug, thus facilitating the manufacturing process. However, in many cases, crystallization is not trivial, and other formulations, such as the concentrate solution, represent the only choice. This is the case of anti-cluster of differentiation 20 (anti-CD20), which is one of the most sold antibodies for therapeutic uses. Here, we propose a set of optimized crystallization conditions for producing anti-CD20 needle-shaped crystals within 24 h in a very reproducible manner with high yield. High crystallization yield was obtained with high reproducibility using both hanging drop vapor diffusion and meso batch, which is a major step forward toward further scaling up the crystallization of anti-CD20. The influence of anti-CD20 storage conditions and the effect of different ions on the crystallization processes were also assessed. The crystal quality and the high yield allowed the first crystallographic investigation on anti-CD20, which positively confirmed the presence of the antibody in the crystals.

Economic Analysis of Batch and Continuous Biopharmaceutical Antibody Production: A Review

PURPOSE

There is a growing interest in continuous biopharmaceutical processing due to the advantages of small footprint, increased productivity, consistent product quality, high process flexibility and robustness, facility cost-effectiveness, and reduced capital and operating cost. To support the decision making of biopharmaceutical manufacturing, comparisons between conventional batch and continuous processing are provided.

METHODS

Various process unit operations in different operating modes are summarized. Software implementation, as well as computational methods used, are analyzed pointing to the advantages and disadvantages that have been highlighted in the literature. Economic analysis methods and their applications in different parts of the processes are also discussed with examples from publications in the last decade.

RESULTS

The results of the comparison between batch and continuous process operation alternatives are discussed. Possible improvements in process design and analysis are recommended. The methods used here do not reflect Lilly's cost structures or economic evaluation methods.

CONCLUSION

This paper provides a review of the work that has been published in the literature on computational process design and economic analysis methods on continuous biopharmaceutical antibody production and its comparison with a conventional batch process.