In the earliest days of biotech, developers often struggled to sustain conditions that would optimize cell health and product yield. Today, better understanding of cells and how they interact with their environment has enabled improvements in most aspects of upstream processing, from bioreactor design and media development to process control, automation, and modeling. 

	Some of the most significant gains have been made in cell line expression, advanced sensors, and automation, says Atul Mohindra, R&D director for biomanufacturing at Lonza Pharma and Biotech. “Using automation, process analytical technologies (PAT), and advanced multivariate analysis has enabled the industry to control process performance and product quality more closely than ever before,” he adds.

	Online sensing has become a focus for many developers, because it enables easier product release and tighter process control, says Avril Vermunt, strategic technologies partnerships leader at GE Healthcare’s life-sciences division. “PAT has matured and is used more routinely now, through in-line pH, dissolved oxygen and carbon dioxide sensors, while use of Raman spectroscopy is increasing,” notes Darren Verlenden, head of bioprocessing at MilliporeSigma.

	In response to extreme cost pressures, companies are using or considering process intensification at every stage of upstream processing, says Andreas Castan, also strategic technology partnerships leader at GE Healthcare’s life sciences group. “We’re seeing shrinking process footprints through continuous integration and connection of upstream and downstream processing,” he says. 

	The end result will be lower capital investment costs, more efficient and flexible operations, and higher yields in less time and space, says Verlenden. Currently, he says, 50–60% of biopharmaceutical developers and manufacturers have either implemented or are considering use of perfusion for seed train or production bioreactor steps. Used with high cell density cryopreservation, perfusion in N-1 and N-2 bioreactors can reduce the cost of goods by 13.5%, shortening run times and increasing production bioreactor titers, he says.

	Improvements and standardization of media have also led to upstream improvements and higher yields. “We’ve consistently been seeing titers in the range of 4–6 g/L in [monoclonal antibody] mAb fed-batch processing within a chemically defined media environment. This environment, in turn, results in more consistent drug product with an improved safety profile,” says Verlenden. Single-use bioreactors at commercial scale (i.e., 2000 L) have become standard, he notes.

	Efforts have been underway for a few years to better integrate upstream and downstream operations to further reduce the overall cost of goods, says Alex Chatel, product manager at Univercells. Some observers credit this trend to increased use of the quality target product profile concept for integrated process design. Some of the latest biopharmaceutical manufacturing facility designs have cell culture and some purification unit operations take place in one location, notes Mohindra. 

	At the same time, the industry is embracing digitalization, notes Vermunt. “New ecosystems for data aggregation, data evaluation, and modeling have been created and leveraged and the bioreactor has been a focus for digital twin efforts,” she says. 

	Projects underway at various manufacturers and technology vendors suggest where upstream manufacturing is heading. One showcase will be Amgen’s facility in West Greenwich, RI, construction of which is expected to be completed in 2020 (1). Leveraging PAT and sensor technology, it will feature a modular design and use portable 2000-L bioreactors and vessels and single-use bioreactors. 

	At the contract development and manufacturing organization Lonza, at-line and on-line sensors have improved control of critical quality attributes, says Mohindra. The company is using in-line sensors and Raman spectroscopy to enable precise measurement of viable cell concentration and individual cell metabolites such as glucose and lactate, he explains. Using real-time data from these sensors has improved decision making, while automating data transcription between systems has minimized risk. Lonza is also moving to the use of electronic batch records to pull information from various systems and build a fully integrated, transparent manufacturing network, says Mohindra. 

	Other efforts focus on process intensification, he says, particularly at the inoculum stage. Over the past three years, Mohindra adds, Lonza has significantly improved host cell expression levels along with its understanding of the design space and interactions between cells, media components, and raw materials. “This understanding is what enables development of new engineering solutions improving speed, cost, and quality,” he says. 

	Bioreactor improvements have been key for most technology providers. GE Healthcare’s life-sciences division, for instance, has updated its bioreactors to enhance process intensification, says Vermunt, and will soon introduce an automatic perfusion system that integrates into the company’s Xcellerex bioreactor platform to facilitate intensification during both N-1 and N stages. The company is also working to improve sensors and use of near infrared and Raman spectroscopy.  

	Similarly, Pall Life Sciences has invested in bench-top automation that allows users more control over processes, says Odette Becheau, senior bioprocess application specialist. Pall’s mPath platform features supervisory control and data acquisition capabilities that allow users to handle process control, monitoring, and data logging. Pall has also developed modeling and scalability tools for its iCellis and Allegro bioreactor lines and is integrating bioreactors with Aber Instruments’ Futura biomass probe for continuous cell biomass measurement, says Becheau.

	Univercells has leveraged process intensification in a new single-use bioreactor design that features a structured fixed-bed bioreactor connected to an automated tangential flow filtration concentrator. The structured fixed-bed contributes to even cell distributions throughout the bed matrix, which improves productivity and reproducibility relative to other commercial systems, says Chatel, while the concentrator reduces the number of downstream operations.

	Over the next five years, experts expect the process intensification trend to continue. Verlenden expects to see greater use of perfusion-developed cell lines, expansion and perfusion cell-culture media, cell retention systems, single-use bioreactors developed for perfusion applications, and associated process automation and control. “Process optimization will run towards maintaining cell densities of over 150 million cells/mL and cultivation run times of over 90 days,” he says. 

	These trends will also drive improvement of single-use technology to support new process templates, especially process intensification and perfusion, says Castan. “Significantly higher cell densities will result in challenges with respect to mixing and oxygen transfer, while new modalities such as cell and gene therapies will require innovation,” he says.

	Movement to continuous bioprocessing will have an impact on bioreactor technology, says Becheau, especially as upstream production processes for viral vectors become mature. She expects to see continued migration from adherent producer cells to suspension cells, as well as the development of stable producer cell lines, which will result in increased productivity per cell, greater use of serum free or chemical defined media systems, and a better understanding and ability to measure media nutrient and feed requirements. “For continuous bioprocessing, development and implementation of more sophisticated cell retention strategies, such as the use of acoustic waves or fixed bed bioreactors, will greatly simplify operations and increase culture performance, mostly by reducing cell shear,” she says. One fundamental near-term change will be an increasing number of new molecular formats in clinical programs (e.g., bispecifics). “We will need to re-tune processes to improve the consistency and quality of products. This also means linking new in-line spectroscopic technology (e.g., Raman sensors) with data handling and analytics,” says Mohindra.

	He sees advances in process control and data analytics as one of the most exciting drivers of change in upstream bioprocessing. “Where we used to be able to measure basic parameters such as dissolved oxygen, pH, and temperature, we can now measure many more complex parameters in real time. The goal is to be able to measure conditions directly where the magic happens-in the actual cell-and this is really challenging the industry,” Mohindra says. 

	Research is underway around the world to help improve upstream processing and overall biopharmaceutical manufacturing. In the United States, a number of efforts are bridging the gap between basic and industrial research by having academic groups and research labs collaborate with companies to help address their top challenges. One example is the Advanced Mammalian Biomanufacturing Innovation Center (AMBIC), a National Science Foundation (NSF)-funded cooperative with 25 corporate members, which is focusing on upstream biomanufacturing and mammalian cell culture and areas such as sensor development and media optimization. The group has developed standard reference Chinese hamster ovary cell lines for research projects to help establish a common baseline for understanding cell responses and improve overall efforts. 

	AMBIC has also developed graphical user interfaces to help member companies optimize media and cell longevity and performance by understanding what is happening within the media and how conditions and changes affect cells.  

	On the bioprocess engineering side, work at the National Institute for Innovation in Manufacturing Biopharmaceuticals (NIIMBL), funded by the Department of Commerce’s National Institute of Standards and Technologies, aims to accelerate development and industrial adoption of manufacturing technologies, says Senior Fellow John Erickson. 

	In February 2020, NIIMBL held a workshop on process intensification with technical leaders from 14 major biopharmaceutical manufacturers and suppliers.  Under discussion is a case study that would establish a common language, standard requirements, and definitions for the control strategies that are needed for integrated, intensified bioprocesses, both on the drug substance and finished drug product side. Erickson sees this effort as being similar in spirit to work on the “A-mAb” case study for quality by design that was done over 10 years ago by the CMC Biotech Working Group (2). 

	Further out in the future, there will be a need for new equipment and approaches to quality control and increased up- and downstream integration. Today, notes Castan, most processes for the production of viral vectors are based on adherent cells, but new expression systems with suspension cells are being developed. These systems will allow existing equipment to be leveraged for suspension cell processes, he explains, but that equipment will need to be smaller for cell and gene therapies than it is in traditional biopharm processes. Integrated systems will be needed to aseptically connect upstream and downstream so that the entire process operates as a closed system, he says. Typically, this has been done by adding aseptic connectors, he explains, but this approach only drives up tube set cost and increases the number of touchpoints for human interaction. “Finding the right balance between functions, compliance, and affordability will likely include new designs and procedural controls,” he says. Traditional quality control (QC) methods will also become outdated as the industry moves to continuous processing. “We will need to replace current QC methods with in-line testing technologies, and they will need to be more accurate, fast, and robust than what exists today,” says Mohindra.

	Change within the biopharmaceutical space has brought with it demands for new skillsets and training. Where, in the past, companies sought biochemists with basic cell culture and purification knowledge, they now require bioengineers with high throughput and automation expertise, says Mohindra. Most manufacturers and technology vendors are partnering with universities to design and deliver courses to help its workers develop the skills required. 

	Currently, more career opportunities are opening up in gene therapy and viral vector manufacturing, but there’s still a large skills gap, says Becheau. “Companies are struggling to find talent with the automation, computer science, and process modeling experience they need,” she says.  

	Another important change is that these more advanced skills are needed on the plant floor. “Tasks that traditionally would have been run by an analytical chemist or a data scientist may now be assigned to an operator, so the next-generation workforce will need to have a diverse background and be comfortable with evolving tools to manage new responsibilities right on the manufacturing floor,” Vermunt says.

	1. Amgen, “Amgen Breaks Ground on Next-Generation Biomanufacturing Plant in Rhode Island," Press Release, July 31, 2018.
	2. L. Bush, “Quality by Design mAb Case Study Challenges Conventional Thinking,” 

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	Vol. 33, No. 3â¨
	March 2020
	â¨Pages: 12-14

	When referring to this article, please cite it as, A. Shanley, "Improving Upstream Predictability," 

Articles

Cover Story: Upstream Processing

Better understanding and control of cell behavior is yielding benefits, upstream and beyond. 


Improving Upstream Predictability

There are ongoing efforts to continually refine and enhance monoclonal antibody (mAb) production, driven in part by the pipeline of upcoming biologic drugs that features many new mAbs in development as well as biosimilar mAbs. To stay competitive, mAb manufacturing processes must maintain desired quality attributes while reducing time to market, being cost effective, and providing manufacturing flexibility. One concern in upstream processing lies in the raw materials used in cell culture. Not only is it critical to have validated sources of purity and quality, it is also important to have sustainable sources.

	Today, commercial mAb production relies heavily on animal-derived source material, particularly in the cell line source. Mammalian expression systems have been the workhorse of mAb bioprocessing, typically using Chinese hamster ovary (CHO) cells. Other mammalian expression systems used include NS0 murine myeloma cells and PER.C6 human cells (1).

	Murine cells, however, produce some byproduct (i.e., alpha-Gal-alpha(1,3) Gal linkages) (1) that were found to instigate an antibody response in patients against the murine-cell derived therapeutic mAb. As a result, mAb production based on murine cells has been limited in the industry.

	Meanwhile, PER.C6 human cells are derived from transfected human embryonic retina cells. These cells are known to multiply indefinitely in suspension culture under serum-free conditions, making them a suitable and practical host for mAb production. The use of human host cells for mAb manufacture is being explored, with one advantage believed to be the compatibility of using a human-cell-derived therapeutic to treat humans. Any residual host cell protein still present in the recombinant product, for example, would be of human origin, thereby lowering the risk that an unwanted or unpredicted immune response may be triggered in the patient against the therapeutic.

	Presently, CHO cells are the predominant cell source used in commercial mAb bioprocessing. CHO-derived cell lines have proven to be robust and high-yielding, or at least easily transfected to be high-yielding. However, production using CHO cells is still costly, and biomanufacturers are seeking ways to cut down on costs. In addition, there has been some evidence that residual CHO host cell proteins in the recombinant end product may have caused an undesired immune response in recipients (2). 

	Alternatives to mammalian cell sources are being explored, including the use of insect cells. In one study (3), product yield, specificity, and glycosylation patterns were compared between insect-cell-based bioprocessing versus CHO-cell-based bioprocessing. The researchers achieved “comparable” amounts of secreted antibodies in the insect-cell-based systems as in the CHO-cell-based system. The antibodies expressed by all the insect cell lines used also successfully displayed highly specific antigen binding. The glycosylation profiles of the antibodies produced in the insect-cell-based systems were also similar to the glycosylation patterns in CHO-cell-based expression.

	The use of insect sources for cell-line starting material can potentially lower production costs for mAbs. Specifically, insect cells used in conjunction with a baculovirus is promising. Such a system is known to be safe because baculoviruses have a very restricted host range (i.e., are highly preferential to a specific range of invertebrate host organisms) and are therefore not pathogenic to plants or vertebrate animals. The major advantage of a baculovirus/insect cell system, however, is the speed with which the system can produce stable, recombinant viruses capable of yielding fully active protein product. An added bonus is that the protein produced would have an easily modulated glycosylation profile. This would mean the product can be easily manipulated to closely resemble human proteins (4).

	The baculovirus/insect cell system is also a familiar one because it has already been in use to product recombinant proteins for research, diagnostics, and for some therapeutics and vaccines. However, further study is required to determine how effective baculovirus/insect-cell-derived antibodies would be in treating diseases, and whether their therapeutic effects would be comparable to the more commonly used CHO-cell-derived antibodies. 

	Animal-free alternatives and future prospects

	Although the use of animal-derived raw materials for mAb cell culture has been the dominant practice in the biopharma industry, there is interest and some movement away from the dependency on animal-sourced material (5). There is already use in the industry of animal-component-free biochemicals and supplements for cell culture media. 

	For example, fetal bovine serum (FBS), traditionally a preferred supplement mammalian cell culture, has largely been replaced by serum-free media and supplements, which tend to be more chemically defined, allowing for greater consistency from lot to lot. Another advantage is the traceability of serum-free, chemically defined media (versus media of animal origin), which supports compliance with global regulatory standards. Serum-free media also provides high biological activity, stable supply, and predictable prices (6). 

	Other attempts to shift away from animal-derived sources involve the use of plant-derived technology. For example, Agenus, a Lexington, MA-based immuno-oncology company, is developing a plant-cell-culture based process to manufacture an adjuvant molecule for use in the production of vaccines (7). The company’s efforts are supported by a $1-million grant from the Bill & Melinda Gates Foundation (8). 

	Meanwhile, iBio, a plant-based biopharmaceutical contract development and manufacturing organization, has been applying its plant-based protein production technologies to advancing the development of rituximab biosimilar and biobetter products (9,10). The company’s technology does not require a cell-line development phase as in traditional mammalian expression systems, which saves time and cost. 

	Another player making inroads with a non-animal-derived cell culture technology is biotechnology company Dyadic International, whose technology revolves around the use of a fungus-based source. The company has developed its C1 expression system based on the 

fungus. The technology can produce proteins at a large scale. The C1 cell line doubles cells in about two hours, which provides two to 10 times higher productivity. Fermentation time is also reduced by one-third to one-half the time needed in a CHO-based system, with the added benefit of accruing only about one-tenth the media cost as CHO (2). 

	Although the prospects for future alternatives to mammalian, and specifically CHO-based, bioprocessing looks promising, the adoption of such processes will not happen overnight. At present, there are many well-established mAbs in the market produced via traditional methods and dependent on mammalian-derived raw materials. However, the shift toward non-animal derived components in some aspects of the cell culture process demonstrate that the industry is actively looking to make a transition, particularly if yield, quality, and cost needs are met.

2 (5) 466–477 (2010).
	2. F. Mirasol, 

31 (11) 18–19 (2018).
	3. D . Palmberger, et al., 

153 (3–4) 160-166 (2011).
	4. M. Cérutti and J. Golay, 

4 (3) 294–309 (2012).
	5. VWR, “Upstream Processing for MAbs,” 

, accessed Feb. 10, 2020.
	6. MilliporeSigma, “Serum-Free Stem Cell Media & Supplements,” 

, accessed Feb. 17, 2020.
	7. F. Mirasol, “Turning to Plant Cell Culture for Sustainability,” 

, Sept. 1, 2019.
	8. Agenus, “Agenus Awarded Grant to Enable QS-21 Innovations,” Press Release, Jan. 3, 2019.
	9. iBio, “iBio’s Collaboration with South Africa’s AzarGen Biotechnologies Advances to Next Stage,” Press Release, Sept. 18, 2019.
	10. iBio, “iBio Reports Progress on Its Bio-Better Rituximab Collaboration with CC-Pharming,” Press Release, Dec. 16, 2019.

l
	Vol. 33, No. 3
	March 2020
	Pages: 16–17

	When referring to this article, please cite it as F. Mirasol, “The Future of Raw Material Sources for mAbs,” 

Upstream Processing

The future of raw material sourcing for mAb production may lay in the sustainability of the source and the added benefits of newer technologies.


The Future of Raw Material Sources for mAbs

As biopharma manufacturers incorporate more data-driven monitoring and control systems in production processes, the quality of the data, as well as integrating, interpreting, and protecting it, become more important. One solution is to build quality features into these systems during process development.

	As a process scales, “there is a need to transfer or integrate process development (PD) data; therefore, building data quality into these activities right from the start is important. Management of data quality always facilitates integration with other systems irrespective of the scientific or business purpose,” observes Chris Andrews, a senior solution consultant with Dassault Systèmes BIOVIA.

	“In the case of monitoring data during process development, it is critical,” Andrews says, “to identify and segregate valid data intended for technical transfer and to ensure that data are clean (i.e., have few invalid results or records) as possible. Higher quality data will minimize integration time, improve the ability to quickly interpret those data, and offer assurance of data integrity and provenance.”

	Establishing a common format for data, units, and terminology will also simplify integration with other systems and prevent confusion during interpretation, adds Kevin Seaver, general manager for bioprocess automation and digital at GE Healthcare Life Sciences.

	In addition, working with secure databases and historians, rather than in flat files such as comma-separated values (CSV) or extensible markup language (XML), allows easier data retrieval and integration along the way, according to Edita Botonjic-Sehic, global PAT manager at Pall Biotech. “Feeding process data into a database immediately enables quicker validation and builds in an element of safety and security that does not come with flat file formats,” she observes.

	Unfortunately, many analytical instruments default to providing data in flat files, and the responsibility to build and connect to databases falls to the user. “Wherever possible,” Botonjic-Sehic says, “this issue should be addressed from the beginning to avoid creating more work or risking loss of critical data on the back end.”

	There are many approaches to data quality management, running the gamut from minimal to strict. The importance of the approach is relative to the criticality of the process being developed, according to Andrews. For example, he notes that “monitoring data for low-risk, well-controlled unit operations or those with historic reliability would require less stringent control and quality management. For new or less well-controlled steps or techniques or otherwise high-risk operations, however, a more robust data quality regimen is called for.”

	“Quality oversight is required for laboratory/pilot-scale studies where process monitoring data will be used to develop the strategy for in-process control and/or support key components of regulatory submissions,” Seaver adds. “The design space defined through these studies provides insight into the criticality and acceptable ranges for controlled parameters and performance or quality attributes. Therefore, interpretation of the results determines the materials, run conditions, and testing strategies for scaling-up and the final commercial process, to ensure the safety, efficacy, and potency of the final product,” he continues.

	As a result, Andrews asserts that for scale-up and commercial processing, data quality is very important. “While not required for licensing, the integration of upstream development data with engineering runs, scale-up, and production data has exceptional business value. There is a wealth of information to be drawn from all phases of the product development lifecycle,” he says.

	It is essential, though, according to Botonjic-Sehic, to not only understand the instrument being used and the data it produces, but also the deeper context behind each data point pulled and stored (metadata). “Beyond tracking a number, a user needs to be able to understand what part of the process gave that number and how it relates to the process performance. If there is inadequate metadata available from the PD scale, then the usefulness of that process data during scale up and commercial processing will be limited. Properly contextualized data is critical for troubleshooting and success as the process is transferred from process development to commercial processing scale,” she explains.

	Quality is achieved through a multi-layered approach. Encompassing all activities and at all stages of the therapeutic product lifecycle should be a culture of quality and commitment to the ultimate endpoint of that product-the patient. “Fostering such a culture of quality is the best way to ensure high-quality process monitoring and control during process development,” Andrews says.

	The next layer involves the leveraging of standards to drive the way that data are stored, transferred and applied to ensure a coordinated approach. Botonjic-Sehic notes that within the pharmaceutical industry, additional guidance that governs data systems helps manufacturers meet regulatory requirements.

	Standards are important because they help minimize the risk to risk to quality, integration, interpretation, and protection, which primarily occurs when data are being transferred and stored. “While interfaces within a piece of equipment are optimized by the supplier, when that piece of equipment must interface with databases, control systems, or other equipment, there are challenges,” Botonjic-Sehic observes.

	Standards describe how best to integrate data across the systems effectively and safely. “There is guidance on communication standards, data formatting, and even coding that helps to facilitate the process from PD to commercial scales,” she notes. In addition, the foundation should start with system design based on ISPE’s Good Automated Manufacturing Practice (1) and integrate the data standards outlined by regulatory agencies such as 21 Code of Federal Regulations Part 11, Annex 11. Supplementary guidance and various industry communities of practice help build a strong solution on that foundation.

	Comprehensive information technology solutions that provide the quality control necessary but also engender compelling and innovative experiences-the third layer-can enable the right quality culture. “Implementation of appropriate technical solutions should reduce friction in accomplishing tasks in addition to providing the array of business benefits, including data quality. If a solution is cumbersome or does not fully meet the business need, users will find a way to work around it, which will assuredly lead to less data integrity. The result can include data silos, dirty (i.e., invalid or incomplete) data, and thus, much more onerous data integration, interpretation, and security efforts,” Andrews observes.

	The fourth layer involves validation. “Where process development data are intended to support key decisions for processing at scale, validation-of the systems used to collate information-or secondary verification-for manual collection-should be performed to ensure quality,” Seaver explains. Validation requires testing against pre-established criteria to confirm that the collection system performs as intended to ensure quality of the data. Manual adjustments made to the data set should be visible through an audit trail to protect against fraud and misinterpretation, Seaver adds.

	Because integration of data is a key component of how any piece of manufacturing equipment works, a strategy for integration must be built in from the start. Too often companies will get excited and build a system based on features, only to think about data integration last; this, however, makes it difficult to deliver a strong data solution, says Botonjic-Sehic. “From the launch of design, data tracking, storage, security, and transferability must be engineered into the system. Creating a ground-up strategy for implementation of standards and ease of integration is undoubtedly the best way.”

	It is also important to avoid manipulation or analysis of the data in a separate program/system, according to Seaver. “Doing so invalidates the quality controls provided through the original system validation. Secondary validation or manual verification would be required to ensure that all information has been transcribed correctly and is accurately represented following analysis,” he explains.

	Neglecting the quality of “unregulated” data, or those that are not necessarily required per an internal standard operating procedure or an external regulatory agency, is another common problem. The result, according to Andrews, can be unexpected downstream quality failures. He also notes that, in general, not ensuring process development monitoring data quality represents a lost opportunity to learn and benefit from that data.

	During a bioprocess, many critical quality attributes (CQAs) and process parameters are monitored to ensure product quality. In traditional processes, samples are taken frequently by manual means and brought into analytical laboratories for testing to ensure product quality has been met; this carries forward throughout the process.

	These methods are labor-intensive, allow for operator error, and do not deliver real-time data, which inhibits their use in continuous bioprocesses, according to Botonjic-Sehic. “Real-time data is extremely important for identifying and mitigating process failures immediately and is necessary to complement the advances in continuous processing,” she asserts.

	To help overcome this industry challenge, Pall Biotech has been focusing on the evaluation and development of new process analytical technologies (PATs) that can measure CQAs in real-time. “The goal is to remove any lag between identifying and mitigating a discrepancy in the process by bringing monitoring closer to the process. By automating analytics and enabling the automatic tracking and processing of data, integrity, and security are built into the process,” observes Botonjic-Sehic.

	The company, she adds, is focusing on the most demanding CQAs throughout the bioprocess. “We do not want to just bring new equipment to the process suite for the sake of it; we want to ensure that we are bringing measurements closer to the process with intelligent and intuitive designs. While there is still not a ‘one-for-all’ approach, different analytical techniques are being evaluated to meet application needs with as much functionality as possible,” Botonjic-Sehic says.

	In addition to real-time data, automation of both the bioprocess and the data collection and analysis, which can be leveraged by a computerized platform to provide real-time feedback control of the bioprocess, can provide an even deeper level of product quality, according to Botonjic-Sehic.

	Pall Biotech has implemented this approach through a framework capable of controlling the process equipment and analytical instruments, automating the data collection and analysis, and feeding the data into developed chemometric models to enable continuous monitoring and control of bioprocesses.

	An integrated human-machine interface (HMI) enables the operator to monitor the process and intervene as needed, ensuring optimum process control and product quality, according to Botonjic-Sehic. She notes that the automated documentation of critical process parameters and CQAs also improves the efficiency of process maintenance, while the chemometric model of each unit operation improves productivity at each step. “Our objective is to have fully automated and integrated control capabilities from end-to-end of the bioprocess, capable of immediately detecting any deviation in either the process or the product, with an HMI giving the operator the tools needed to mitigate those deviations, saving time, reducing batch failures, and improving overall product quality and consistency at every scale,” concludes Botonjic-Sehic.

	Advances in digital technology are also contributing to greater quality for data monitoring and control systems. For instance, cloud-based storage environments are making it easier to bring together data generated on process and analytical equipment, according to Seaver. “This information can be linked to the purpose of the study in electronic laboratory notebooks to provide the context. It has also made it possible to compare information across studies, multiple projects/molecules, and scales to better understand risk,” he says.

	The popularity of coding languages and technologies, such as the Industrial Internet of Things, has also led to amazing innovation in the areas of therapeutic development lifecycle data processing, adds Andrews. “The advance of communication and encryption technologies mean data provenance and non-repudiation are more reliable,” he explains.

	1. ISPE, ISPE GAMP 5 Guide: A Risk-Based Approach to Compliant GxP Computerized Systems, February 2008.


	Vol. 33, No. 3
	March 2020
	Pages: 18–22, 38

	When referring to this article, please cite it as: C. Challener, “Building Data Quality in Generates Quality Data Out,” 

Downstream Processing

Ensuring the quality of data in process monitoring and control systems starts in process development phases.

Building Data Quality in Generates Quality Data Out

Industry experts have noted that there are limitations in the number of scalable technologies for viral-vector manufacturing and limited expertise in large-scale manufacturing (1). Yet demand is growing, and flexible and efficient facilities will be needed for multi-product clinical and commercial manufacturing.

	“In the viral vector space, there is diversity around different vector types (e.g., lentivirus [LV], adenovirus [AV], and adeno-associated virus [AAV]). It’s critical to have a facility design that is flexible enough to adapt to product pipeline diversity,” says Joe Makowiecki, Enterprise Solutions director of business development at GE Healthcare Life Sciences.

	Modular facility designs and modular construction are being used in biologics manufacturing, with a key benefit being faster time from inception to startup. The BioPhorum Group hosted an industry collaboration that proposed a standardized, modular design approach to help advance facility design in the industry (2). While the initial project looked at a monoclonal antibody (mAb) facility, the team plans to extend the concept to cell and gene therapy production.

	GE Healthcare Life Sciences has amassed expertise in modular design and construction with the use of its FlexFactory (a modular end-to-end biomanufacturing platform) as well as its KUBio facility (the FlexFactory inside of a prefabricated facility) for biologics production at facilities around the world. In 2019, the company introduced the KUBio Box-a box-in-box approach, the FlexFactory platform in a modular facility intended to be placed inside a new or repurposed space or shell-building-tailored for viral-vector-based gene therapies (3). 

	“Speed to market is critical for most, if not all, biologics. This is quite relevant in the gene therapy segment as many gene therapies are qualifying for orphan drug status or fast track designation status, shortening the drug development timeline from seven to 10 years for traditional biologics to three to five years,” says Makowiecki. He says the KUBio box for viral vectors is a current good manufacturing practice (CGMP), biosafety level (BSL) 2 modular facility solution that can be delivered in 10 to 12 months.

	Viral-vector manufacturing has some similarities to mAb manufacturing, but also some differences. “Compared to mAbs, viral vectors are much larger, more complex molecules that are highly susceptible to various factors in their manufacturing environment, such as mechanical shear, pH, and temperature,” says Makowiecki. “Viral vectors are typically more expensive to manufacture as most viral vectors, due to their potential infectivity, require an increased BSL classification: BSL-2 classification for most viral vectors compared to BSL-1 classification for traditional mAbs. BSL 1 focuses on protection of the product from the operators and the environment, and BSL 2 focuses on containment, protecting the operators and the environment from the product. Increased biosafety level classification adds manufacturing and facility complexity and costs.”

	Makowiecki says that many new facilities today are designed to use single-use technologies and to produce multiple products, which may require different sizes of equipment. “There is quite a bit of variability when it comes to viral vector manufacturing scales. It depends on the use of the vector (i.e., is it used as a reagent, as in the case of gene modified cell therapies, or is it the end drug product) and the indication (i.e., is it a local injection or a systemic dose). In the viral-vector space, we see process scales from one to 2000 L. There is less variability for lentivirus and gamma retrovirus that is used for virally genetically modified cell therapies (

 gene therapies); the scale is mostly 50 L and currently doesn’t go beyond 200 L. Whereas for 

 gene therapies, using mostly AAV, the scale varies depending on the patient population, disease type, and route of injection, from a few 10 L up to 2000 L. For example, for Duchene muscular dystrophy, the need (at current viral titers and downstream process recoveries) is about 200 L of production bioreactor culture per patient.” The batch size influences the equipment size and number and, thus, the facility design, he notes.

	When larger batches are needed, either scale-up or scale-out is used, depending on the type of process. Makowiecki explains that vector production using adherent cells in fixed-bed bioreactors is limited in scale primarily by the size of the fixed-bed bioreactors, and scale-out is used to increase production volume. One option would be to convert to a suspension cell process and stirred tank bioreactors. Another option would be to use adherent cells with microcarriers in stirred-tank bioreactors. Both options typically do not have scale limitations and thus would allow for a more scalable process.

	The initial KUBio box for viral vector production was designed for a 200-L process scale, but Makowiecki says the company intends to also design larger-scale KUBio boxes for viral vector production.

Modular facility speeds clinical research

	In December 2019, GE Healthcare Life Sciences and the University of Massachusetts Medical School (UMMS) announced that they would install a large-scale viral vector manufacturing facility on the school’s Worcester, MA campus to provide large quantities of high-quality AAV vectors for preclinical research. The 3220-ft

 facility will use a good laboratory practice (GLP) viral vector FlexFactory manufacturing platform. GE and UMMS said that the new capacity would help to alleviate the bottleneck of vector supply, as currently researchers potentially wait 12 to 24 months to obtain enough vectors for their research. The facility will be fully operational in 2020 (4).

	“Flexibility enables manufacturers to leverage different technologies and systems in our plants, which can be beneficial when working with different manufacturing platforms and different scales,” says Christopher Murphy, vice-president and general manager for Viral Vector Services at Thermo Fisher Scientific, which acquired viral vector manufacturer Brammer Bio in March 2019. The company has been busy expanding, and, in December 2019, it opened a 50,000-ft

 facility in Lexington, MA to provide capacity for the contract development and manufacturing organization (CDMO) to support viral vector development and manufacturing (5). In November 2019, the company completed a $6-million expansion of its gene therapy and viral vector services facility in Alchua, FL that doubled the site’s laboratory and warehousing capacity for upstream process development and quality control testing of gene therapy products (6). “Logistics and warehousing are vital to the success of our operations. We look to leverage centralized warehousing with just-in-time deliveries to our manufacturing plants,” says Murphy.

	Murphy says the company’s facilities are engineered to support multiple products and processes, and that it has developed best practices through its recent capacity expansion programs. “Challenges included ‘right-sizing’ manufacturing suites and designing air systems and personnel flows to maintain segregation,” notes Murphy. The facilities use single-use systems. Murphy says the primary benefit for single-use systems is eliminating the need to perform cleaning validation on reused product contact equipment.

. 43 (9) 22-26 (2019).
	2. BioPhorum Group, “Improving the Biomanufacturing Facility Lifecycle Using a Standardized, Modular Design, and Construction Approach,” White Paper, June 2019.
	3. GE Healthcare Life Sciences, “New KUBio Box for Viral Vectors Boosts Gene Therapy Manufacturing,” Press Release, Oct. 28, 2019.
	4. GE Healthcare Life Sciences, “Academic-Industry Collaboration: Viral Vectors for Preclinical Research,” Press Release, Dec. 16, 2019.
	5. ThermoFisher, “Thermo Fisher Scientific Opens $90 Million Viral Vector Manufacturing Site in Massachusetts,” Press Release, Dec. 4, 2019.
	6.ThermoFisher, “Thermo Fisher Scientific Unveils $6 Million Expansion at Viral Vector Manufacturing Facility,” Press Release, Nov. 22, 2019.


	Vol. 33, No. 3
	March 2020
	Pages: 23-24

	When referring to this article, please cite it as J. Markarian, “Flexible Facilities for Viral Vector Manufacturing,” 

Manufacturing

Single-use and modular systems will meet demand for rapid implementation at different scales.

Flexible Facilities for Viral Vector Manufacturing

According to market research, the global pharmaceutical analytical testing outsourcing market is projected to have strong growth from 2020 to 2027 (1). Drivers of this growth include an increase in demand for biopharmaceuticals, biosimilars, and analytical drugs, in addition to a general requirement for bio/pharma companies to streamline operations and reduce costs.

	To learn more about the criticality of stability testing throughout drug development, potential differences with small versus large molecules, regulatory requirements, and future trends, 

spoke with Ramesh Jagadeesan, senior director of analytical development, Recipharm; and Karin Kottig, manager contract service analytics, Vetter Development Services.

Could you elaborate on the importance of stability testing throughout the various development steps of drug products? 

Stability testing is one of the most crucial steps in the development of new drug products. By performing a series of analyses, testing programs can determine how long a product will maintain the properties and characteristics it possessed at the time of manufacture. The effect of environmental factors (such as temperature, light, and humidity) on a formulation’s purity, efficacy, and structure is evaluated over time to define both its shelf-life and the necessary storage conditions. This information is vital for the regulatory approval of a new medicine. 

	Stability studies are conducted during all phases of drug development. They typically start at the preclinical stage of drug development and continue through Phase I–Phase III clinical trials to support formulation development, and to satisfy the regulatory requirements for clinical trials. However, the purpose of the studies and regulatory requirements vary depending on the product type, the phase of the program, and the intended markets. 

	The first stage of stability testing usually takes the form of forced-degradation studies. These studies help to identify the ideal formulation from a host of different candidates to take forward for further testing. The aim of this is to understand the primary degradation products of a molecule and aid analysts in selecting the best methods for further stability tests, which mimic real-life storage in different global regions. Long-term stability studies will subsequently be initiated and validated on both the API and the drug product.

	In short, the aim of the stability testing process is to produce data that demonstrates whether any physical, chemical, or microbiological changes affect the efficiency and integrity of a pharmaceutical product. This helps to ensure medicines are safe and effective, irrespective of where in the world they are supplied. 

Stability studies are an essential and vital part of drug development. They are necessary throughout all phases with stringent timelines for analytical testing. The purpose of the studies is to prove how the quality of an API or drug product changes over the course of time while under the influence of environmental conditions such as temperature, humidity, or light. Stability studies also support the determination of the re-test date of the active ingredient, shelf-life of the drug product, suitable packaging materials, and recommended storage conditions. 

	With respect to new drug applications, submissions for approval by regulatory authorities are required to contain data from stability studies conducted on both the drug substance and the drug product. During drug development, this assessment is performed with the help of a variety of well-designed stability studies in the different development phases. During early development, stability studies are performed on technical batches as well as on clinical samples. These include, for example, stress and accelerated studies of the drug substance and product to support setup of formulation, selection of primary packaging, and production process. In later phases, transport and cycling studies as well as long-term and accelerated studies with registration batches are realized. All data are compiled to generate the expiration date of the drug and, finally, to obtain the market authorization. 

	After product launch, follow-up stability studies of market batches are conducted on a regular basis. The studies are also necessary after post-approval changes. In this way, they significantly influence the entire lifecycle of a product. Ultimately, they are essential to provide a drug and thus the health of the patient by supplying a stable product with consistent quality.  

Are there specific differences in terms of stability testing for small-molecule versus large-molecule products? 

From complex and highly sensitive substances to vaccines and biotechnologically produced proteins, the manufacturing of drug products demands a high-degree of expertise and flexibility to perform all the necessary and product-specific processes prior to the independent completion of the final product. Thus, stability testing required for ensuring a product is fit for use are adapted on a case-by-case basis. 

	The increasing number of biologics in clinical development has had a significant impact on analytical methods and has brought forth new scientific challenges. When it comes to injectables, biologics are placed into a small volume of liquid that often requires a very high concentration. This leads to unique stability issues related to aggregation, viscosity, and thermal degradation. And, while still relatively complex, it is usually a straightforward process to demonstrate the identity, correct content, and purity of small-molecule drugs and the correlated products. The evaluation of the quality of a biological, large-molecule product requires much more complex analytical and bioanalytical methods. 

	From my point of view, the increased focus on particulate matter is also correlated to large-molecule products as they are often very sensitive. Aggregation, as well as interactions with other components such as excipients and packaging material, for example, could lead to increased particulate matter formation. These particulates will then be analyzed with different analytical methods. 

The development of an appropriate stability testing program typically considers the specific nature of the product being evaluated. Based upon the constituent compounds and knowledge of how they are impacted by storage and environmental conditions, the degradation dynamics of small-molecule products are predictable. The rise of newer, large-molecule drugs developed using biotechnology has brought new scientific challenges for stability testing. 

	The greater complexity of large-molecule products, combined with more batch-to-batch variance and specialized storage conditions, makes typical stability study conditions unsuitable. To this end, bespoke stability testing programs need to be designed for each product. Biopharmaceuticals are generally highly concentrated and/or less soluble, which increases the likelihood that the API will precipitate during stability studies. Clear, quality data surrounding this process are essential to ensuring regulatory compliance.

	In addition, small-molecule degradation pathways are more predictable and shelf-life specifications are set based on the toxicological studies. Whereas, with biopharmaceuticals, degradation pathways are much more unpredictable, and they differ for different proteins. For example, some parenteral biologics administered for patients are highly concentrated, so they may precipitate during the stability studies. 

	Biopharmaceuticals are often only stable over a very limited temperature range, meaning that excursions/temperature deviations outside the optimum storage conditions can have a significant impact on stability. To this end, they should be stored within an extremely narrow temperature range to avoid an impact on biological activity. Testing the stability of such sensitive products in a range of temperatures needs to be carefully planned to take actual storage conditions into consideration. Additionally, the stability of proteins often calls for other analytical methods other than the liquid chromatography that is frequently used for small organic molecules.

What are the regulatory expectations for stability testing? 

The International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) has established stability testing guidelines that provide comprehensive guidance on registration stability requirements for new drug applications in the ICH regions. These guidelines recommend different testing protocols for climatic zones around the globe. For example, storage stability tests can range from temperatures as low as -80 °C to 40 °C, with relative humidity up to 75%. The ICH guidelines have been adapted by many regulatory agencies including the European Medicines Agency (EMA) and FDA for its abbreviated new drug applications pathway. 

	There are, however, marked differences in the specific stability data required by authorities in each market. As a result, testing programs should be developed with the specific market in mind. For example, despite authorities in the United States and European Union adopting the same standards, they set different microbiological limits for stability tests. In addition, some assessments that can be omitted in the US are mandatory in the EU and vice versa. 

	Stability testing of pharmaceutical products is mandatory for regulatory approvals. If a product fails to meet the standards prescribed by the ICH, as well as those defined by the World Health Organization, the product will not be granted approval for commercialization. Planning, execution, and completion of studies in given timelines plays a major role in securing approval and ensuring a product reaches patients. 

Drug stability is not simply a requirement of the regulations. Rather, stability testing operations are a ‘window’ for the development program of the product and the assurance of quality. Practically all regulatory requirements for drug stability testing are clearly described in [good manufacturing practices] GMP guidelines. Today, stability plans include far more than just the determination of an expiration date for a pharmaceutical product. They also require a written stability testing program that specifies sample sizes and test intervals, controlled storage conditions, validated and specific test methods, and specifications. Furthermore, requirements stipulate that an adequate number of drug production batches are tested. In addition, it is mandatory to perform stability testing of the product in its marketed container or closure system. 

	There has been considerable harmonization of regulatory guidelines, with the ICH pharmaceutical stability guidelines now recognized as the globally accepted industry standard. ICH provides practical guidance on the amount and the type of drug substance and drug product stability data needed to support marketing applications. The included quality guidelines Q1A–Q1F have made a major contribution to increasing the quality of pharmaceuticals and are applicable for small molecules. Generally speaking, they apply to large-molecule products as well. ICH Q5C takes into consideration the specific characteristics of biotechnological/biological products. These large-molecule products are typically more sensitive than small-molecule products and require complex analytical methods to demonstrate that their molecular conformation is maintained during shelf life. For example, a potency assay is required to prove biological activity is maintained. Usually, more than one analytical method is needed to prove purity of the product. 

As molecules in development become more complex and difficult to deal with, what trends do you predict may impact the industry over the next 5–10 years in the area of stability testing? 

As the demand for biopharmaceuticals increase, even more efficient methods will need to be in place for the assessment of protein activity. This makes it necessary to have access to more analytical technology compared to when handling small molecules, where liquid chromatography can fulfill most analytical needs.

	A great challenge in product development is the time it takes to ensure stability. There is a significant need for methods that enable the prediction of the stability of a formulation at an early stage as this will allow companies to shorten development timelines and reduce the risk of unforeseen challenges later on in stability studies. 

	While APIs are growing in complexity, there is also a trend towards more complex formulations, such as nanoparticles, microemulsions, and amorphous formulations to give acceptable solubility and bioavailability. For these formulations, physical-chemical characteristics, in particular solid-state characteristics, are very important; hence, this leads to the need for more physical-chemical characterization during stability studies.

When addressing the challenges of increased complexity of molecules in development in combination with even shorter timeframes for drug development and smaller batch sizes, the pharmaceutical and biotech industry should collaborate with regulatory bodies to generate meaningful risk-based guidance. Holistic approaches will require good data management and integrated systems to collect, manage, and process data to effectively support stability analyses in the future. 

Grand View Research, “Pharmaceutical Analytical Testing Outsourcing Market Size, Share & Trends Analysis Report by Service (Bioanalytical, Stability Testing, Method Development, and Validation), and Segment Forecasts, 2020–2027,” 

Felicity Thomas is the European editor for 


	Vol. 33, No. 3
	March 2020
	Pages: 26–28

	When referring to this article, please cite it as F. Thomas, “Stability Testing: The Crucial Development Step,” 

Analytics

As compounds become more complex in nature and biological ingredients are more widely used, stability testing approaches must follow suit and provide flexibility for developers.


Stability Testing: The Crucial Development Step

The focus on developing emerging therapies, especially cell and gene therapies, has intensified, making the need for good manufacturing practices (GMP) guidance more imperative. In its specific efforts to promote the development of novel gene therapies, FDA published six final guidance documents on gene therapy manufacturing and clinical development and released a draft guidance on gene therapy products under orphan drug regulations in January 2020. To date, the agency has approved four gene therapy products (1). 

	How do these new FDA guidance documents help gene therapy developers and contract service providers navigate the challenges of gene therapy development and manufacturing? The

Chemistry, Manufacturing, and Control (CMC) Information for Human Gene Therapy Investigational New Drug Applications (INDs) 

(2) guidance, for one, provides a comprehensive framework to guide the development of a broad range of products, says Karen Magers, head of Regulatory Affairs Cell and Gene Therapy Technologies, Lonza. The guidance document provides many recommendations that help to clarify the expectations for product development, characterization, manufacturing, and testing of these products, she points out.

	“Stakeholders, including Lonza, submitted comments [to FDA] requesting clarification on the information to be submitted prior to a first-in-human clinical study and information to be submitted in a phased approach, as more manufacturing experience is obtained during product clinical development. FDA acknowledged in the final document that ‘information may be limited in the early phases of development and recommends that sponsors provide additional information and updates as product development proceeds’,” she states. However, because limited specific recommendations and examples were provided in the guidance, there are remaining challenges in determining the requirements for first-in-human studies and subsequent clinical studies, she continues.

	Others note that, with the guidance documents, the challenges to gene therapy development and manufacturing are what they have always been. “I don’t think there is anything unexpected in the final CMC guidance,” says James Blackwell, PhD, principal consultant and president of The Windshire Group, a Boston, MA-based biopharmaceutical consulting group. “The challenges are what they have always been. However, there are numerous challenges posed in the guidance for developers.”

	Blackwell narrows down challenges his group has experienced, which will likely be the same experiences that other stakeholders in gene therapy development will also experience. First, for any combination product or potential combination gene therapy product, developers should carefully assess the available guidance and make early assessments in the program because the regulatory and documentation requirements can vary significantly for various components. “For areas of doubt, one should engage the Health Authorities early. This can be a challenging area for emerging technologies,” Blackwell says.

	Blackwell also points out that there is a higher burden, compared to traditional products, for gene therapies to understand critical attributes and parameters earlier in the development cycle while trying to establish as robust of a process as early as possible. This burden stems from the complexity of a gene therapy product. 

	“The benefits of doing so are dual. First, you minimize the need for change later and, if change is needed, you have a more solid basis for rationalizing and approaching it to minimize impact to development timelines. The latter point is always important but will be a key consideration for many of these programs,” Blackwell states.

	“Containers used for drug substance and drug product need to be closely scrutinized for products that can’t be filtered,” he continues. “The level of particulates may not be controlled as closely as needed during the manufacture of these components, and the particulates will end up in your product if not controlled or removed in advance. For some of these suppliers, a gene therapy developer represents such a small part of their overall business that the supplier will not accommodate changes deemed necessary by the developer. Particulates and their potential to cause adverse events have been the subject of increasing regulatory scrutiny.”

	The bottom line to having these gene therapy guidance documents, however, is to facilitate not only the development and current good manufacturing practice (CGMP) compliance of gene therapies, but also the regulatory pathway to drug approval. “I’ve found the guidances, including these, to be invaluable to understanding expectations. One thing that stands out to me in these guidelines was the number of places the agency understood there may be differences in approach or technical, practical, and scientific limitations to meeting the ideal requirements of the guidances,” Blackwell emphasizes.

	“Still, in those situations, knowing what the expectation is helps one develop a rationale, data set, and construct that address the issue and why the alternate approach does not represent a risk to the safety, identity, strength, purity, and quality (SISPQ) of the product,” he adds.

	The two guidance documents (2,3) that include CMC-specific recommendations also provide clarity on many aspects related to the manufacturing and testing requirements for gene therapy products, Magers asserts. “[These] documents provide both general guidelines and specific recommendations. As an example of a general guideline, FDA provided information supporting the classification of viral vectors. Comments on the draft 

document sought this clarification. In the final version, FDA cited regulation to confirm their position that a vector ‘used to transduce cells 

and which furnishes a pharmacological activity for the treatment of disease is a critical component. Without the vector, the resulting cell product would not have the same pharmacological activity. Similarly, a vector in its final formulation for administration of the genetic material is generally considered a DP [drug product]’,” Magers cites.

	She notes that FDA gave examples of specific vector recommendations, which include replication competent retrovirus (RCR) testing of cell banks, vector-harvested material, and 

transduced cells. FDA had also given an example of the derivation in its recommendation for an appropriate test volume for RCR detection.

	At present, there are still hurdles to overcome in the manufacturing of gene therapies, and a number of biopharmaceutical companies as well as contract manufacturing organizations/contract development and manufacturing organizations are tackling these challenges. 

	For one, gene therapy (and cell therapy) manufacturing is still a highly manual aseptic manufacturing process, which poses several challenges, says Magers. It is important to consider the correct and functional layout of cleanrooms and the number of trained operators needed for those cleanrooms, he points out. She also emphasizes the high importance of ensuring the qualification of sterile consumables and raw materials because, often, only research-grade material is available and there is no GMP material available to replace them when manufacturing is scaled up. 

	“We are also observing a high investment in infrastructure and facilities in contrast to low throughput areas (personalized medicine, small batch sizes-down to one batch per patient), as well as unclear expectations for concurrent manufacturing of several batches and product segregation strategies,” Magers notes.

	Navigating the regulatory landscape and complying with regulations can be difficult as an international manufacturer, Magers also observes. “There are three main regulatory systems: European Union (EU) GMP regulations, United States (US) GMP regulations, and Pharmaceutical Inspection Co-operation Scheme (PIC/S) regulations,” she states. “The new 

Good Manufacturing Practice Guidelines on Good Manufacturing Practice Specific to Advanced Therapy Medicinal Products 

(EU GMP part IV) (4) does not provide the most straightforward guidance and expectations. Moreover, it refers to risk management, which is not easy to navigate, as the perception of risk is subjective to a certain extent.”

	Magers also points out that these new EU guidelines exclude the link and reference to GMPs for other pharmaceuticals, including in 

Annex 1, Manufacture of Sterile Medicinal Products (Corrected Version) (5)

. “However, the PIC/S and the US will not adapt to this move. Therefore, the ‘classical’ pharmaceutical regulations apply to products that will be licensed in those regions. Furthermore, many countries are part of more than one of these regulatory systems (e.g., EU GMP and PIC/S, US regulations and PIC/S); navigating through expectations from different regulatory bodies will soon arise and need to be complied with,” she adds.

	“I think one of the biggest challenges will be the complexity of the supply chain demands, both on the front end (starting with supply of materials or patient samples) and back-end (delivery to the patient),” observes Blackwell. 

	“Some of these products and technologies use relatively novel materials, and the suppliers are not mature from the standpoint of their manufacturing processes and quality systems. In some cases, the sponsor will need to help the supplier and improve and reduce risk. The bar keeps getting raised as the products enter Phase III and commercial manufacturing. So how these critical components will be sourced in a compliant manner needs to be assessed early in development and planned for with risk-reduction strategies,” Blackwell adds.

	Blackwell brings up another source of compliance complexity: data integrity requirements and management of these data from patient, to testing and manufacturing, and back to patient. “Now imagine that this is all happening by paper documentation now. As patient loads increase in clinical trials, managing this and avoiding and dealing with mistakes becomes herculean, if not impossible. The integration of compliant electronic tracking and data-sharing technologies from patient to lab, to manufacturing, and back to patient is paramount and a challenge,” he stresses. 

	Further, the definition of the “control space” around the product is becoming another hurdle. For traditional products the “control space” has entailed batch manufacturing, batch area clearance, and various room checks to limit the risk of cross contamination and product mixups. For many of the newer technologies, Blackwell asserts, the traditional manufacturing model simply won’t be economical. 

	“The control space around the product will need to shrink to accommodate simultaneous and parallel manufacturing on the same production floor. Again, the interplay of data technologies (e.g., radio frequency identification, wireless, mobile, barcode, manufacturing execution system) and engineered controls (e.g., electronic batch records) to ensure compliance and the SISPQ of the product will be essential. These systems will need to interact with the quality system in real time and be validated to support release by exception. Unexpected events will need to be investigated immediately and alerted by the electronic process monitoring systems,” Blackwell explains.

	Gene therapy stakeholders would do well to have a set of best practices that will help keep the development of a novel gene therapy in compliance with new regulatory guidelines. Early and frequent use of risk assessments is a good practice that can greatly enhance process understanding and focus efforts, for instance. Gene therapy, as well as other emerging therapy products, required a broad and deep understanding of the science behind them in order to do proper risk assessments, Blackwell says. “This will often entail close collaboration between R&D scientists, process scientists, and quality control, especially early in the development program before little process data and manufacturing history has been garnered,” he adds.

	Blackwell considers that stakeholders for a number of these products will seek expedited approval pathways, which will compound the challenges with CMC because of the shortened timelines. He notes that it is always challenging to keep CMC off the critical pathway under any circumstance, and when these pathways get expedited, the pressures on CMC activities are enormous. Unfortunately, there will be no relief from FDA in terms of meeting the expectations and spirit of the guidance documents. “Again, strategic and project planning that links to the data and technical reports requirement and regulatory expectations is clearly a best practice,” Blackwell says. 

	Blackwell believes it is helpful to always keep the end-goal (i.e., commercialization) in mind. “Is a change really needed now, or can it wait until after approval and commercial launch? But, having the end-in-mind is not enough. Starting early with a strategic and project plan focused on regulatory requirements and guidance pays tremendous dividends. It helps to make sure things are not overlooked, and helps the team make appropriate adjustments quickly when things don’t go as planned. They almost never do,” he says.

	Another best practice Blackwell recommends, though on a different tact, relates to process, equipment, and facility validation. “Many of these processes will need to scale up on parallel and not in scale like traditional products. Thus, the master validation plan should accommodate this by simplifying the level of qualification needed for new product lines and suites,” Blackwell says.

	He also advocates using quality-by-design and product lifecycle approaches, which are the best ways to meet all these challenges. “For example, the target product profile is one of the few tools in an organization that brings most of the key stakeholders together, including commercial, medical, CMC, regulatory, and quality; keeps everyone on the same page; and focuses efforts. Start early with it since it becomes a living document that has the end-in-mind,” Blackwell states. 

	Meanwhile, although the new gene therapy guidelines issued by FDA are a significant step forward in moving new gene therapies through the regulatory process toward approval, some note that further GMP guidelines are still needed. Magers points out that although GMP requirements have been issued that are specific to gene therapy products, FDA has not yet issued a guidance document that contains detailed GMP recommendations.

	The EC’s GMP guidelines for advanced therapy medicinal products (4) that went into effect in May 2018 contain detailed recommendations, Magers observes. “Some of these recommendations were included in the PIC/S GMP Guide 

Annex 2A Manufacture of Advanced Therapy Medicinal Products for Human Use 

(6), which was issued for public comment from September to December 2019. FDA is providing recommendations to address specific topics (e.g., recommendations for multiproduct cell and gene therapy manufacturing facilities) in public forums, however, no guidelines have been issued,” Magers states.

	“In addition, it would be beneficial if FDA would update some CMC guidance documents to reflect their current thinking. Guidelines that should be updated include the 

Content and Review of Chemistry, Manufacturing, and Control (CMC) Information for Human Somatic Cell Therapy Investigational New Drug Applications (INDs)

Potency Tests for Cellular and Gene Therapy Products Final Guidance for Industry

, issued January 2011. Further, a guideline addressing comparability approaches for cell and gene therapy products is needed, as changes are often made during the development of these products that require an assessment of comparability,” Magers adds.

	Blackwell points to an area where future guidance will likely be needed, and that is in “bedside manufacturing” and “distributed manufacturing” in non-GMP environments. “The CGMPs, guidances, and technology will be pushed to its limits to ensure the SISPQ of the product is ensured. Guidances that will be particularly useful will be on process analytic technology (PAT), 

] Part 11, and risk assessment, but I expect new guidance that tie these together in conjunction with these types of technologies will be needed. For example, how will the quality unit oversee and interact with these technologies? What will be deemed acceptable? Appropriate engineering controls; analytics, testing, and release; validation; data integrity; handling unexpected events; handling and control over the manufacturing equipment will be especially challenging,” he concludes.

While new industry guidance documents issued by FDA speak to the agency’s efforts to promote the development of new gene therapies, certain hurdles remain to challenge stakeholders.

BioPharm International-03-01-2020

Improving Upstream Predictability

The Future of Raw Material Sources for mAbs

Building Data Quality in Generates Quality Data Out

Flexible Facilities for Viral Vector Manufacturing

Stability Testing: The Crucial Development Step

Navigating GMPs for Gene Therapies

The Costs of Commercializing CRISPR

Seeking Early Answers to Formulation Questions

Drug Production Draws Multiple Contenders

Coronavirus Response: Reaction or New Reality?

Embracing Change Management

BioPharm International, March 2020 Issue (PDF)