mAb Downstream Processing
Optimization of the downstream steps in monoclonal antibody (mAb) processing is critical to ensuring product quality, yield, and sterility. Getting the most out of every step depends on a broad range of products, services, and solutions to meet the different needs of each process.
Accelerating clarification of pretreated feed streams
Increasingly efficient upstream processes enable biopharmaceutical manufacturers to achieve higher cell densities and antibody titers. This improved upstream efficiency has led to new purification challenges resulting from high product and contaminant concentrations. Harvest and clarification technologies are evolving to incorporate feed stream pretreatment, including flocculation and different filtration methods such as normal flow, tangential flow, and depth filtration to improve separation efficiency. The objective is to increase process capacities and filtrate quality, while minimizing biomanufacturing costs.
For example, pretreating feeds with a flocculation reagent followed by depth filtration is an effective clarification solution for harvesting high cell density cultures, with easy integration into current platforms. The flocculation reagent acts as a binder to aggregate cells and cellular debris into larger particles within a solution. Primary clarification filters specifically designed for harvesting of high cell density cultures are now available, removing larger particles by using their depth for sieving while maintaining good adsorption capacity.
Related Product Resources
- Article: pDADMAC Flocculation in Monoclonal Antibody Production Processes – Overcoming Regulatory Challenges with Quality Risk Management
- mAbsizer™ Calculator Tool
The mAbsizer™ Calculator estimates the quantity of Merck products required to express, purify, and formulate a mAb effectively.
- Webinar: Challenges and Options in High-viscosity Tangential Flow Filtration
Overview of available TFF solutions for achieving high viscosity of monoclonal antibodies and plasma IgG, and strategies for reliable cycle-to-cycle cleaning.
- Webinar: Intensified mAb Polishing: Linking Single Pass Tangential Flow Filtration with Anion Exchange Chromatography
There is growing interest within the biopharmaceutical industry to improve individual unit operation performance by intensification and overall process train efficiency through linked and continuous processing.
- Technical Brief: Techniques for Demonstrating Cleaning Effectiveness of Ultrafiltration Membranes
Tangential flow filtration cartridges designed to isolate, purify and concentrate therapeutic biomolecules are typically reused for multiple process cycles.
- Application Note: pDADMAC Flocculant Reagent for Use with Clarisolve® Depth Filters
In recent years, advances in cell line engineering and cell culture media design have allowed for improvements in monoclonal antibody expression, with cell culture systems exhibiting product titers greater than 10 g/L.
- Application Note: Natrix® Q Chromatography Membrane
Comparison of process-related impurity clearance for resin-based chromatography technologies.
- Application Note: Natrix® Q Membrane Adsorber
Comparison of process-related impurity clearance for membrane adsorbers.
- Application Note: Intensified Polishing Using SPTFF with Anion Exchange Chromatography
The bioprocessing industry is interested in Next Generation Processes with higher flexibility, lower costs, and higher product quality.
Intensifying mAb polishing with single-pass TFF and anion exchange chromatography
While it is common for mAb downstream purification processes to use a flow-through anion exchange (AEX) resin as a final impurity adsorption step, this conventional polishing step can lead to process bottlenecks due to large columns with long processing times. A growing number of manufacturers are taking advantage of a new solution: pre-concentrating the mAb feed before the AEX column by connecting inline single-pass tangential flow filtration (SPTFF) with AEX chromatography. This approach improves the AEX resin’s capacity for HCP impurities and minimizes the bottleneck at the AEX polishing step.
Increasing purification efficiency using chromatography membrane
Conventional purification technologies generally require trade-offs in process design. For example, resin-based chromatography columns are often oversized due to throughput limitations and are less compatible with flexible manufacturing. Conventional membrane adsorbers offer faster throughput, but their low binding capacity may not provide sufficient process robustness.
To overcome these limitations, a new generation of high-capacity, high-throughput AEX chromatography membrane has been developed, combining high binding capacity and flow rates in a single-use plug-and-play format. This new option for purification offers the potential of more productive, flexible, and robust process design.
Handling high-viscosity feeds associated with increasing concentration
Converting infusion-based treatments to subcutaneous injections can increase patient comfort and satisfaction. The challenges to development of these solutions include:
- Delivering a much higher concentration drug
- Designing an efficient ultrafiltration process, using high-quality formulation buffers
- Overcoming viscosity limitations with some TFF systems
TFF cassettes designed for high-viscosity operation enable drugs to be concentrated without modifying current systems or replacing pumps.
Excipient combinations to decrease viscosity of highly concentrated protein solutions can be used to improve process economics during TFF. This can ultimately enable a higher final protein concentration in formulation still administrable with standard syringes.
Optimizing reuse and storage of TFF cassettes
Qualification of TFF cassette reuse, lifetime, and storage is important during optimization and qualification of any manufacturing process. Understanding the requirements and risks of TFF cassette storage and reuse is essential to developing a comprehensive validation plan and mitigating potential risks of product recalls or plant shutdowns.
Optimizing cleaning for extended chromatography resin lifetime
Chromatography resins are a major contributor to monoclonal antibody production costs. To improve process economics and maximize resin lifetime, resins should be effectively cleaned before reuse to remove fouling species.
Optimization of resin cleaning procedures over multiple cycles through traditional lab-scale experiments is time-consuming and requires a significant amount of feed material. However, miniaturized, high-throughput screening tools can be used to optimize resin cleaning procedures. Studies at miniaturized scale accelerate the time to results, while minimizing the volume of feed material and buffers required.
Related Videos
Workflow
Upstream
The upstream process begins with cell line development and includes all steps up to cell harvest, with the goal of increasing cell densities and product titers to maximize mAb production
Final Filtration and Filling
Final filling of drug products must meet stringent requirements for sterility, integrity, cleanliness, operational safety, and efficiency
Viral Safety
Based on the principles of “prevent, detect, and remove,” viral safety combines risk analysis with careful selection of raw materials, extensive testing of raw materials and process intermediates, and implementation of virus reduction steps in downstream processing
Bioburden Control
All mAb production processes are at risk for microbial contamination, requiring a process design with control strategies to mitigate the risk, as well as bioburden monitoring to assure process control
Aggregate Removal
Protein aggregates are a concern throughout upstream and downstream mAb manufacturing, and control is key to maximizing process efficiency and robustness
To continue reading please sign in or create an account.
Don't Have An Account?