What Are the Benefits of Single-Use in CGT Manufacturing?

Cell and gene therapy (CGT) manufacturing presents many challenges. The one-patient-per-batch paradigm for autologous cell therapies presents unique small-volume production challenges (1). While often not personalized treatments, gene therapies have been developed for single patients (2), and many target rare and ultra-rare diseases and, therefore, require small-volume manufacturing solutions. Risk of contamination and cross-contamination is high, making assurance of sterility a primary concern (1). Single-use systems when used in conjunction with barrier technologies, automation, and comprehensive contamination control measures provide a means for mitigating that risk.

Pre-validated single-use assemblies eliminate the need for clean-in-place and steam-in place processes, reducing the time and cost of process setup while also ensuring sterility from the outset (1–3). Standardized assemblies when used with automated equipment further avoid complex design and validation processes. At the same time, modular single-use systems can be sufficiently flexible to support scale up and modification to accommodate changing requirements for different products in multi-product facilities (3). In addition, single-use technologies (SUTs) are available to support all aspects of upstream and downstream cell and gene therapy manufacturing operations (4).

Overall, SUTs are seen as key enablers of CGT manufacturing, ensuring the production of safe, high-quality products while reducing timelines and cost (5).

Why is single-use-technology ideally suited for CGT manufacturing?

There are many reasons why SUT facilitates CGT manufacturing. First, it can be leveraged in both upstream and downstream operations. “In the context of unit operations, essentially all of them are ideally suited for single-use processing to segregate patient samples, protect operators from potential viral particles, and ensure consistent processing,” explains Tony Hsiao, senior product manager for bioproduction innovation at Thermo Fisher Scientific.

Upstream, single-use systems are deployed to support cell culture and other activities. “Cell and gene therapy processes often involve multiple steps, for example, in the case of CAR-T [chimeric antigen receptors] therapy manufacturing,” says Joe Gallagher, technical applications manager with Avantor. “After apheresis, there are multiple steps such as cell selection, enrichment, and activation, each potentially requiring separate assemblies, components, and compartments. Single-use tubing, bags, and sterile connectors are commonly used to link these steps in closed or functionally closed workflows, allowing manufacturers to move seamlessly between operations without extensive cleaning or risk of cross-contamination.”

Hsiao highlights the benefits of SUTs for cell expansion. “Cell expansion, in particular, often dominates the overall processing time from vein-to-vein for cell therapies, and so the ability to parallelize processing to speed up throughput is greatly aided by using single-use expansion systems that can be operated concurrently.”

Downstream processes, Gallagher observes, like tangential-flow filtration, chromatography, and buffer preparation, also benefit from disposable solutions. “Single-use fluid paths and disposable flow paths are especially valuable in viral vector purification, final formulation, and fill-ready transfer steps, where sterility assurance and product recovery are critical,” he notes. Gallagher adds that single-use fluid paths are even more critical in cell therapy, where sterile filtration is not an option given the size of the product cells.

Moreover, SUTs facilitate automation, according to Gallagher, as skids and robotic systems are much easier to integrate with flexible, single-use assemblies than with fixed stainless-steel infrastructure. “This adaptability is crucial for facilities managing multiple patients, products, or modalities,” he contends.

Beyond their wide applicability across unit operations, SUTs are, says Hsiao, well-positioned to prevent contamination and product loss concerns by maintaining closed systems and providing pre-sterilized materials for quick turnaround. “Building on the track record from other parts of biopharma allows advanced therapy producers confidence in applying SUTs in their processes,” he comments.

In addition, SUTs are a strong fit for CGT manufacturing because these therapies are produced in small, patient-specific batches, Gallagher points out. “In autologous therapies, each batch is made from an individual patient’s own cells, which requires frequent changeovers and high flexibility. Pre-configured, disposable fluid paths can be quickly deployed and swapped between patients, supporting this manufacturing model,” he says.

Single use is, according to Emmanuelle Cameau, scientific director, viral vectors at Cytiva, the only viable option in these cases due to the need for sterility and the impracticality of cleaning validation for each patient batch.

Furthermore, the ability to ensure material segregation and consistent, clean starting material is hard to match with reusable systems, according to Hsiao.

Traditional stainless-steel systems, Gallagher adds, are poorly suited to this environment. They are designed for large volumes and require extensive cleaning and sterilization between batches, which adds downtime, complexity, and operational risk. “Single-use assemblies, such as pre-sterilized tubing, connectors, and disposable components, eliminate cleaning requirements and enable faster turnaround,” he concludes.

Even for larger-scale processes (e.g., viral vector production) for which stainless-steel reactors may be used, Cameau observes that SUTs are preferred where validation is most difficult or where sterility is paramount.

Gallagher also notes that single-use systems support closed or functionally closed processing using sterile connectors, custom assemblies, and disposable sensors, allowing many open, manual steps to be converted into closed or semi-automated operations, reducing contamination risk. While single-use components may have higher material costs, he believes their benefits in speed, flexibility, and cleanliness make them well suited for CGT manufacturing. He does remark, though that these advantages are greatest when single-use systems are supported by strong quality standards, full traceability, and robust supplier change management, which are critical in regulated CGT manufacturing environments.

How does the use of SUTs support the flexibility needed for CGT operations?

CGT processes lack a fixed template, often evolve, and may require production capabilities from very small to larger scales. SUTs provide the flexibility essential to meeting these needs, according to Gallagher. “Manufacturers may need to adjust workflows, product types, or batch sizes quickly, sometimes within the same facility. Single-use assemblies can be easily reconfigured or replaced, making these changes faster and simpler to implement,” he explains.

For instance, says Hsiao, the ability to directly scale out SUTs for autologous cell therapies allows producers to reduce speculative capital investments and plan their operations and expenses in a more straightforward way based on the batches they need and the patients they will treat. Meanwhile, allogeneic cell therapies and some gene therapies for which the target population is often not large, he adds, also lend themselves well to SUT solutions and equipment that process in the range from one to thousands of liters.

The rapid changeovers between batches made possible by SUTs are, observes Cameau, particularly beneficial for facilities handling both smaller and larger batches, and for maximizing facility utilization. As such, this flexibility is especially valuable for contract development and manufacturing organisations (CDMOs), which often need to reshuffle unit operations to accommodate different molecules and workflows.

It is also important, notes Gallagher, for CDMOs that support multiple modalities, such as autologous, allogeneic, and gene therapies, using shared infrastructure. Disposable mixing bags and fluid paths, he comments, allow rapid changes in buffers or media without modifying fixed equipment or risking cross-contamination, making product transitions more efficient. For instance, single-use magnetic mixing systems that range in size from 10 to 1500 liters and are designed to deliver comparable fluid dynamics offer the consistency needed to help ensure processes scale efficiently. “By combining adaptability with closed-system integrity, single-use systems make it feasible to operate efficiently across a wide variety of cell and gene therapy workflows,” Gallagher concludes.

How does the use of SUTs facilitate automation of CGT operations?

SUTs can be used with automation solutions to increase production efficiency, but further advances in technology, particularly related to sensor, are needed. “The production of advanced therapies can be quite varied with respect to automation today,” Hsiao says. “At one end, some producers are still relying on basic incubators to provide temperature and gas mix control. On the other end, some are deploying robotics to reduce labor and risk from human interventions in their processes. Interestingly, these two can merge where a very complicated robot is putting a product into an incubator where there is no feedback control capability,” he explains.

In and of themselves, Gallagher believes that single-use assemblies are integral to automation because they provide the physical interface for fluid movement within skids or robotic systems. “Importantly,” he notes, “this automation sets the stage for advanced process analytical technology (PAT).” He observes that pumps, sensors, and process control modules can operate efficiently with disposable assemblies, enabling closed systems that maintain sterility while reducing human error. Real-time monitoring is another advantage, as single-use sensors can track parameters such as pH, dissolved oxygen, and metabolite levels, allowing manufacturers to make immediate adjustments to cell growth conditions rather than relying on delayed sampling and analysis.

This feedback-driven approach supports more consistent product quality and better compliance with regulatory expectations, Gallagher contends. Additionally, he points to single-use designs that integrate optical windows or compatible sensors for advanced process analytics as enabling automation not just to be possible but also scalable, even in small-batch or early-stage manufacturing environments.

Currently, however, Cameau emphasizes thatSUTs do not yet fully facilitate automation. “The industry is working to address this issue, but there are still significant gaps, particularly around sensor compatibility,” she says. Many sensors are not yet fully compatible with single-use systems, which slows down automation and data collection. The main challenges highlighted by Cameau are automating accurate data collection from sensors, ensuring chemical compatibility, and maintaining accuracy after processes like gamma irradiation, “While fully automated, single-use facilities exist, achieving seamless automation remains a standard the industry has not yet reached,” she states.

What are the most important attributes that should be considered when selecting SUTs for CGT manufacturing?

When selecting single-use systems for cell and gene therapy, several critical factors must be considered. “One challenge is that existing tools may not always actually be the best tool, and so it is important to understand if the SUT is fit for the purpose you need in the therapy you are producing,” comments Hsiao.

An example might be an adherent cell-culture platform that has high porosity to allow high-density cell growth. This, says Hsiao, could be perfect for a gene therapy process where viral particles are shed into the media for collection. It might be terrible, however, for a gene therapy requiring cell lysis or a cell therapy to get all the cells released from tortuous pores. “For all SUTs in an advanced therapy workflow, it is important to pay attention to quality standards and claims to understand what fits with the specific process. Sometimes you might need a medical device to interact with a patient. Other times in your processing that is unnecessary,” he concludes.

Compatibility with the product and process is also paramount, according to Gallagher. The material of construction must not interact with cells, buffers, or media, and extractables and leachables must be understood, especially in the context of recent updated International Council for Harmonisation (ICH) Q3E guidelines (6).

Beyond overall fitness-for-purpose and compatibility, other important aspects of SUTs highlighted by Cameau include sterility, system integrity, the risk profile, and the value of the process fluid. “Sterility and system integrity are crucial for steps requiring a sterile environment. With respect to risk profile and product value, typically upstream steps may have higher contamination risk, while downstream steps involve higher-value products and stricter cleaning validation,” Cameau says.

Integration with sensors is another consideration highlighted by Gallagher, as many workflows, both now and in the future, will rely on real-time monitoring for process control. “Supply chain reliability is increasingly important, especially considering the experiences during the COVID-19 pandemic, when high demand for plastics disrupted production. Regional availability and multiple sourcing options can mitigate these risks,” he notes

“Given these factors, the choice of SUTs should be tailored to the application and the risks at each stage,” Cameau contends.

What are best practices for ensuring successful implementation of SUTs in CGT manufacturing?

When selecting SUTs for CGT manufacturing, it is, says Hsiao, best to start with the end in mind and select the highest-grade materials as early as possible to avoid the need to redo development work later or the need to conduct additional, extensive risk assessments and qualification of the materials. “Successful implementation of single-use systems begins with early planning,” Gallagher agrees. Considering the final-scale process from the outset is essential to avoid redesigns during clinical or commercial expansion.

Conducting thorough risk assessments and risk management should, in fact, be pursued from the outset, Cameau observes. Choosing suppliers wisely, a reliable supply chain, high quality, expertise, and trusted partnerships are also essential, she comments. Implementing single-use across the entire workflow, not just individual steps, helps avoid the burden of cleaning validation for hybrid processes, Cameau notes. Ensuring connectivity between systems, especially when working with multiple suppliers, is equally important for avoiding integration issues. Finally, Cameau believes delegating some responsibility for quality and supply to the supplier is an important strategy for building stronger supplier relationships.

Hardware choices also matter, according to Gallagher. “Selecting platforms that are compatible with existing systems and scalable to larger volumes reduces risk and accelerates adoption,” he says. Integration with sensors, process monitoring, and automation should also be considered as part of the overall design, observes Gallagher. “By planning for flexibility, scalability, and interoperability from the beginning, manufacturers can ensure that single-use systems deliver efficiency, reproducibility, and regulatory compliance throughout the product lifecycle,” he concludes.

What recent SUTs introduced to the market for CGT manufacturing have had the biggest impact?

Many recent impactful advances in SUT have brought proven benefits of single-use systems from biopharma into the CGT space, according to Hsiao. He highlights bioreactors with built-in pH and dissolved oxygen sensing, which allow for an increased level of control and repeatability not found in passive systems. The ability to attach SU perfusion systems, Hsiao also notes, further enhances the benefits of control and allows for maximizing yields through intensified processes. He also expects additional PAT solutions that continue to be introduced to the CGT space to find great once their compatibility with SUTs has been demonstrated.

Recent innovations in SUT of note to Gallagher have focused on closing previously manual, open processes and improving control across all steps of manufacturing. He points to pumps that minimize shear stress and preserve cell viability, single-use mixers capable of maintaining homogeneous suspensions, and skids designed to automate processes like plasmid DNA harvest or buffer preparation.These solutions, he observes, increase reproducibility, reduce batch-to-batch variability, and support compliance with regulatory standards like 21 Code of Federal Regulations Part 11. “By integrating automation and closed systems, manufacturers can scale operations more efficiently and reduce risks associated with manual handling. Such innovations have had an outsized impact on early-stage manufacturing and clinical-scale production, where maintaining consistent quality and yield is essential for commercialization,” Gallagher contends.

Specific technologies from Cytiva that Cameau views as having a major impact in CGT manufacturing include iCELLis fixed-bed bioreactors, which she says have been particularly important for for viral vector production and commercialization of gene therapies, and the NanoAssemblr nanoparticle synthesis system for lipid nanoparticle (LNP) production, which was used in the manufacture of COVID-19 vaccines and has enabled significant breakthroughs in scale-up and commercialisation. Most recently, Cytiva launched the Sefia cell therapy manufacturing platform comprising two digitally integrated and functionally closed systems that automate key manufacturing steps (7). “These innovations have supported larger patient populations and more efficient manufacturing,” Cameau states.

For what applications in CGT manufacturing are SUT solutions still needed?

Several areas in the CGT space remain underserved by current single-use solutions. Allogeneic cell therapy at a larger scale is, for instance, still challenging because most equipment is optimized for autologous workflows, according to Gallagher. Custom single-use equipment that addresses this gap could significantly improve scalability.

Lack of standardization continues to be an issue as well due to the different origins (academia, clinics, biopharma) of CGT processes and SUT equipment coming from both the blood and biopharma sectors, says Hsiao.

Semi-automated, closed single-use assemblies can reduce variability and contamination risk in processing steps, says Gallagher. In addition, he highlights opportunities in the regenerative and immune-modulating cell therapies space including washing, trypsinization, and other delicate manipulations of adherent cell manufacturing, where controlled single-use systems can help standardize processes that are traditionally labor-intensive and prone to human error.

There is also a need for further process intensification and automation, including better integration of sensors, AI-driven modeling, and prediction, according to Cameau.

Hsiao agrees. “Greater advances in PAT and perhaps even bringing quality-control tools earlier into the process coupled with predictive methods might increase how quickly we can release our products. A single-use cell phenotype sensor, for example, would be amazing, as would a single-use empty-full capsid sensor,” he comments.

Cost, Cameau notes, also remains a major challenge, especially for smaller batches and personalized therapies. “More cost-effective and sustainable solutions (e.g., recycled materials, smarter manufacturing units, integrated unit operations) are needed,” Cameau contends. She also believes the industry must address the environmental impact of single-use technologies and promote sustainable practices

What innovations, regulatory changes, and technology advances are expected for SUTs in CGT manufacturing?

Many of the shortcomings that still exist with SUTs for CGT manufacturing are anticipated to be addressed in the near future. Hsiao expects not only greater standardization across products so that producers will be able to choose from many more compatible options, further guidance from regulatory bodies that will aid interconnectivity, and additional translation of existing tools into this space from biopharma that will allow for soon more consistent advanced therapy production.

Gallagher predicts that innovations in connectors, robotics compatibility, and closed-system design will continue to expand what can be automated and scaled up or out, while maintaining sterility. In viral vector production, he believes closing and automating transfection and harvest steps will be particularly impactful, reducing contamination risk and lowering cost.

“Overall,” Gallagher concludes, “the trajectory for single-use systems is toward greater customization, integration, and reliability, which will further establish its central role in the future of CGT manufacturing.”

References

1. Van Hagen, A.; Drinkwater, J.; Milne, J. Advantages of Single-Use in Cell and Gene Therapy Manufacturing Platforms. Pharmaceutical Manufacturer, Dec. 5, 2022.https://pharmaceuticalmanufacturer.media/pharmaceutical-industry-insights/pharmaceutical-manufacturing-insights/advantages-of-single-use-in-cell-and-gene-therapy-manufactur/
2. Andelyn. Accelerating Development of Gene Replacement Therapy to Treat NEDAMSS. Andelyn Biosciences Blog, July 15, 2025. https://www.andelynbio.com/resources/accelerating-development-of-gene-replacement-therapy-to-treat-nedamss
3. Single Use Support. Cell and Gene Therapy Production–Improvements with Single-Use Technologies. Labroots.com. March 4, 2024. https://www.labroots.com/trending/cell-and-molecular-biology/26734/cell-gene-therapy-production-improvements-single-use-technologies?srsltid=AfmBOopgfZpKnL-XaZSvTz6dbAYjhX1bHOPfqqUj-w97UObtthtTYLnA
4. Hsiao, T. Scaling Up Gene Therapy Manufacturing with Single-Use Technology. Thermo Fisher. October 2020. https://documents.thermofisher.com/TFS-Assets/BPD/Reference-Materials/scaling-up-gene-therapy-manufacturing-sut-article.pdf
5. Avantor. The Need for Single-Use Technology in Cell and Gene Therapies. https://www.avantorsciences.com/ca/en/support/knowledge-center/single-use-technology-cell-and-gene-therapies
6. ICH, Q3E Draft Guideline for Extractables and Leachables, Step 2 (ICH, August 1, 2025).
7. Cytiva Communications. Innovation and Automation Are Driving Forces Behind Next Generation Cell Therapy mMnufacturing Platform from Cytiva. Press Release, May 29, 2024. https://www.cytivalifesciences.com/en/us/news-center/cytiva-unveils-new-cell-therapy-manufacturing-platform-10001.