As biologic drug development accelerates, proprietary cell line platforms offered by contract development and manufacturing organizations (CDMOs) have become vital infrastructure for speed, scalability, and regulatory success. Originally built around monoclonal antibodies, these platforms now support an expanding range of modalities — including bispecifics, Fc-fusion proteins, viral vectors, and microbial-expressed enzymes — through host-optimized systems like CHO, HEK293, and E. coli. By standardizing cell lines, media, and processes, platforms can compress development timelines to under a year while minimizing risk. However, they also introduce limitations in flexibility, innovation space, and fit for atypical molecules. The next generation of CDMO platforms is integrating AI/ML, modularity, and feedback loops to support increasingly complex pipelines and evolving regulatory expectations.
The Platform Imperative
Over the past two decades, biologics have taken center stage in drug development pipelines, with monoclonal antibodies (mAbs), bispecific antibodies, antibody–drug conjugates (ADCs), Fc-fusion proteins, gene therapies, and other complex modalities emerging as essential tools in the treatment of cancer, autoimmune diseases, and rare genetic disorders. This diversity has brought with it a corresponding rise in development complexity. As programs push into the clinic faster, often with limited internal infrastructure, companies are under increasing pressure to move from sequence to Investigational New Drug (IND) applications in record time — sometimes under a year — while maintaining the robustness, consistency, and quality that regulatory agencies demand.
The lean structures of many biotech companies exacerbate these pressures. With fewer in-house resources for cell line development, process optimization, or regulatory strategy, the need for predictable, turnkey solutions is more acute than ever. Timelines are tight, budgets are limited, and the competitive landscape favors those who can de-risk early development and reach clinical proof of concept quickly. In this environment, proprietary platforms offered by contract development and manufacturing organizations (CDMOs) have emerged as a critical enabler of speed, scale, and success.
Historically, companies developed custom cell lines and processes for each biologic program, a resource-intensive and often unpredictable undertaking. Today, many CDMOs offer proprietary, pre-validated platforms that combine high-yielding expression systems with optimized media, scalable upstream and downstream processes, analytical toolkits, and regulatory documentation frameworks. These platforms are designed to streamline the path to IND by minimizing trial and error and reducing variability across programs. For many sponsors, particularly those developing mAbs or other well-established formats, such platforms can compress timelines to under 9–12 months and provide a clearer regulatory path forward.
What began as a solution for mAbs has now expanded into a far more sophisticated offering. The best of today’s CDMO platforms can accommodate increasingly complex molecule types, from bispecifics and Fc-fusions to viral vectors and exosomes. As these offerings evolve, they are becoming more modular, more digitally enabled, and more tightly integrated with commercial-scale manufacturing infrastructure. In many ways, proprietary CDMO platforms have transitioned from operational tools to strategic infrastructure, helping define not just how a biotherapy is made but how quickly and successfully it can reach patients.
A Brief History of Cell Line Platforms
The modern era of biologics manufacturing is built on a foundation that began to take shape in the early 2000s, when Chinese hamster ovary (CHO) cells became firmly established as the industry’s expression system of choice. CHO cells offered a compelling combination of adaptability, regulatory familiarity, and the ability to perform human-compatible posttranslational modifications. These traits made them ideally suited to produce mAbs and other complex therapeutic proteins, and CHO quickly became the default host cell line for biopharmaceutical development.
As biologics pipelines grew, the limitations of standard CHO expression began to surface, especially with respect to productivity, consistency, and speed. This prompted the development of proprietary expression systems that would come to define the next phase of innovation. Among the most notable were the glutamine synthetase (GS) and dihydrofolate reductase (DHFR) systems, which introduced powerful selection mechanisms and supported the generation of high-producing stable clones. These systems, often housed within CDMOs or specialized platform companies, allowed developers to improve expression levels while streamlining the path to clinical-grade cell lines.
These developments were contemporaneous with an evolution in the role of CDMOs. Initially viewed primarily as capacity providers or toll manufacturers, CDMOs began offering more strategic value by integrating cell line development, process optimization, and regulatory expertise into full-service platforms. This shift mirrored broader changes in biomanufacturing, including the adoption of single-use systems and the emergence of more agile, modular production models.
In the 2010s and 2020s, platform sophistication grew considerably. CDMOs began incorporating digital tools, including design of experiments (DoE) software, modeling platforms, and artificial intelligence and machine learning (AI/ML) algorithms to enhance clone selection, media optimization, and process development. These capabilities not only improved efficiency but also increased predictability, a critical driver of both speed and regulatory compliance.
During this same period, the industry saw a growing need for expression systems beyond CHO. Programs involving proteins not requiring glycosylation, such as enzymes and peptides, spurred renewed interest in microbial systems like Escherichia coli. Yeast systems such as Pichia pastoris gained traction for vaccine and enzyme production, while human embryonic kidney (HEK293) cells, particularly in suspension-adapted forms, became essential for viral vector production and difficult-to-express proteins. As CDMOs expanded their modality coverage, many began developing proprietary platforms for these alternative hosts as well, enabling more tailored approaches to complex programs.
Current CDMO platforms reflect this rich history of technological layering, strategic repositioning, and expanded modality focus. They offer not merely speed and productivity but a structured and predictable development path across a wide range of biologic formats.
Key CDMO-Owned Cell Line Platforms
The current landscape of CDMO-owned expression platforms reflects a wide range of remain built center around CHO-based expression for mAbs and related modalities, the market has expanded to include systems optimized for viral vectors, microbial expression, and even exosome production. Grouping these platforms by host system and typical application helps clarify the comparative strengths and limitations of each approach.
CHO-Based Platforms for mAbs and Beyond
CHO remains the cornerstone of biopharmaceutical production, particularly for mAbs, Fc-fusion proteins, and other glycosylated proteins requiring complex post-translational modifications. Several CDMOs have developed proprietary CHO-based platforms that offer high titers, scalability, and strong regulatory track records.
GS Xceed® (Lonza): Based on Lonza’s CHOK1SV host cell line and glutamine synthetase selection system, GS Xceed combines high-performance expression with a history of regulatory success. It includes optimized media, feeds, and process templates designed to accelerate timelines and reduce variability. The platform is used across a wide range of mAbs and has been increasingly applied to complex formats like ADCs.
WuXiUP™ (WuXi Biologics) is an ultra-high productivity platform derived from CHO-K1 that supports titers exceeding 30 g/L. Built for continuous processing and late-stage manufacturing, WuXiUP is often paired with WuXiBody™ — a bispecific antibody platform that simplifies manufacturing by mimicking mAb-like behavior in expression, purification, and formulation.
S-CHOice™ (Samsung Biologics) is a proprietary CHO platform integrated into the company’s S-Cellerate™ development framework. It emphasizes high-yield expression, early manufacturability screening, and rapid timelines, aiming to move from DNA to IND in as little as nine months.
SUREtechnology™ (Selexis / KBI Biopharma) is built around the SURE CHO-M cell line, engineered for genetic stability and high productivity. Widely used for mAbs and increasingly applied to multi-specific proteins, it is known for enabling rapid clone selection and scalability from early development through commercial production.
HEK293 and Transient Expression Platforms
HEK293 cells and transient systems offer advantages in speed and posttranslational complexity, making them useful for early-stage screening, difficult-to-express proteins, and viral vector production. Although they are generally less scalable for large-scale mAb manufacturing, they play an important role in accelerating development or enabling formats incompatible with CHO.
Expi293™ / ExpiCHO™ (Thermo Fisher / Patheon) are widely adopted transient expression systems used in early-stage development and preclinical protein production. CDMOs like Patheon integrate these systems into broader development platforms, allowing clients to quickly generate material for iˆstudies or lead candidate selection.
AAV Curator™ Platform (Andelyn Biosciences) is a purpose-built platform for AAV vector development, designed to support gene therapy programs from discovery through GMP manufacturing. The system integrates platform-derived plasmids, HEK293 suspension cells, and a scalable, high-yield upstream process. AAV Curator™ is engineered for consistency and efficiency, offering a robust CMC framework, modular analytical package, and process adaptability across serotypes. With a track record of clinical success and commercial readiness, it is a leading example of how CDMOs are extending the platform model beyond proteins to viral vectors.
Microbial and Yeast Expression Systems
For non-glycosylated proteins, microbial systems such as ˆand yeast like ˆoffer fast growth, low-cost media, and well-established production protocols. These platforms are especially useful for enzymes, peptides, and certain vaccine components.
pAVEway™ PLUS (FUJIFILM Biotechnologies) is a high-efficiency ˆlatform designed to overcome common bottlenecks such as inclusion body formation. It supports high yields of soluble protein and is backed by robust downstream processing capabilities.
XS Pichia™ (Lonza): Based on Pichia pastoris, this yeast expression system is well-suited for secreted proteins that don’t require complex mammalian glycosylation. It provides an alternative to CHO for certain enzymes and vaccine candidates and benefits from Lonza’s platform infrastructure and process knowledge.
Other or Emerging Platforms
As biologics continue to diversify, CDMOs are investing in new and emerging expression systems. These include CHO-K1 lines enhanced via CRISPR engineering for better productivity or quality attributes and ongoing work in cell-free protein synthesis and AI-optimized expression libraries. Many platforms are also integrating continuous manufacturing and perfusion-based processes, enabling more efficient scale-up and real-time process control.
While not yet as widely available or validated as the CHO-centric platforms, these emerging systems reflect the industry’s forward momentum. They promise new solutions for hard-to-express proteins, low-yield modalities, or clients seeking even faster development cycles and lower cost of goods. As they mature, these innovations are likely to further expand the boundaries of what CDMO platforms can offer.
Matching Platform to Program: Comparative Insights
With the growing diversity of biologic modalities, selecting the right expression platform has become a strategic decision with implications for speed, cost, scalability, and regulatory success. While many CDMOs offer broad capabilities, their proprietary platforms tend to be optimized for specific molecule types or production goals. Matching a program to the right platform early in development can accelerate timelines and reduce the risk of needing to switch systems midstream.
Which Platform for Which Modality?
The most established CHO-based platforms — GS Xceed®, WuXiUP™, S-CHOice™, and SUREtechnology™ — remain the best fit for traditional mAbs, offering high titers, rapid development timelines, and a well-defined regulatory precedent. WuXiUP™ and WuXiBody™ are particularly well suited for bispecifics, with the latter specifically engineered to simplify bispecific antibody development using standard mAb-like processes. SUREtechnology™ also provides strong flexibility for multi-specific and structurally complex constructs.
For ADCs, platforms like GS Xceed® and WuXiUP™ provide the robustness and scalability needed to support both antibody production and site-specific conjugation workflows. Fc-fusion proteins, which often have higher aggregation or stability risks, benefit from the early manufacturability assessments and formulation development built into platforms like S-CHOice™ and SUREtechnology™.
When it comes to gene therapies, CHO platforms are generally unsuitable. Instead, systems like the AAV Curator Platform from Andelyn Biosciences offer a fit-for-purpose solution for AAV vector production, balancing yield, scalability, and compliance with viral vector-specific quality requirements.
Microbial and yeast platforms fill a different niche, supporting programs that do not require glycosylation. pAVEway™ and XS Pichia™ are ideal for enzymes, peptides, and certain vaccine subunits, providing high expression levels and straightforward purification workflows with lower cost of goods.
Speed vs. Flexibility
Off-the-shelf CDMO platforms are typically optimized for speed. By standardizing cell lines, media systems, and upstream/downstream processes, these platforms can often move a candidate from gene to IND in less than 9–12 months. However, this speed comes with some tradeoffs. Platform processes may not accommodate atypical constructs, unusual glycosylation needs, or specific formulation requirements. For programs that fall outside the typical use case, such as large or aggregation-prone proteins, platforms may need to be modified or abandoned, which can introduce delays.
The degree of flexibility varies by platform. Some CDMOs allow extensive client-specific customization of media, process parameters, and analytics, while others maintain tighter control to preserve platform integrity and speed. Sponsors with novel or high-risk molecules must weigh the benefits of rapid progression against the risk of late-stage fit issues.
Regulatory Advantage
Another key benefit of proprietary platforms is their regulatory track record. Platforms that have supported prior IND or biologics license application (BLA) filings reduce uncertainty around cell line history, characterization methods, and process validation strategies. Many CDMOs also provide standardized chemistry, manufacturing, and controls (CMC) documentation modules as part of their platform offering, simplifying regulatory submissions and reducing sponsor workload.
These advantages can be especially important for small or emerging biotechs without internal CMC infrastructure. By leveraging a platform that has already passed regulatory scrutiny, companies can focus more on clinical development and less on manufacturing risk. As regulators become increasingly familiar with certain platforms, their predictability becomes a strategic asset in accelerating product development.
Caveats: Where Platform Approaches Fall Short
Despite their advantages in speed, efficiency, and regulatory predictability, proprietary CDMO platforms are not universally suited to every biologic program. These systems are designed around standardized assumptions and optimized for the most common molecule types — primarily well-behaved mAbs and their close relatives. For programs that fall outside this mainstream profile, platform-based development can introduce friction or even risk.
Programs That Don’t Fit the Mold
Some biologic formats present challenges that exceed the design parameters of existing platforms. These include constructs with atypical architecture, rare posttranslational modifications, or highly charged or hydrophobic domains. For instance, molecules that require unusual glycan structures or disulfide linkages may not express well in CHO or may demand specialized downstream processing that diverges from the platform norm.
Other common outliers include candidates with high viscosity or poor solubility, which can complicate both expression and formulation. Novel bioconjugates, such as protein–drug fusions or conditionally activated payloads, may also pose stability, clearance, or aggregation challenges that require bespoke solutions. In these cases, a rigid platform approach can become a liability, leading to lower yields, product heterogeneity, or extended troubleshooting that offsets any initial time savings.
Hidden Tradeoffs
Even when a molecule technically fits within a platform’s capabilities, relying on a standardized system can introduce hidden tradeoffs. Because platforms are calibrated for the median case, edge-case behavior may not become apparent until later stages of development. Sponsors who push a molecule through early milestones using a forced platform fit may find themselves needing to transfer to a custom process or reformulate entirely, which can introduce new regulatory complexity and delay.
Intellectual property considerations also deserve attention. Some CDMO platforms include licensing terms or usage restrictions that limit how the cell line or process can be used outside of that relationship. For biotech sponsors planning to out-license or transfer the program to a different manufacturer, these limitations can complicate deal structures or tech transfer plans.
Limited Innovation Space
By their nature, platform approaches involve a degree of standardization that can limit experimentation. Sponsors are often required to use a fixed media system, follow prescribed upstream and downstream workflows, or adopt standard analytical methods. While this ensures consistency and simplifies regulatory filings, it can constrain innovation in process development, especially for companies looking to explore novel purification techniques, media formulations, or quality attributes.
For small biotechs hoping to build internal capabilities or generate differentiated IP around manufacturing, heavy reliance on a CDMO’s proprietary platform may limit opportunities to innovate or to build institutional knowledge. In some cases, the long-term strategic value of developing custom infrastructure may outweigh the short-term gains of platform speed.
Ultimately, while CDMO platforms are powerful tools, they are not one-size-fits-all solutions. Sponsors must weigh their benefits against the specific needs and risks of the program and be prepared to pivot when the fit is not quite right.
The Future of Platform-Based Development
As CDMO-owned expression platforms become increasingly central to the speed and success of biologics development, the next generation of platform innovation is already taking shape. These advances aim to address current limitations, broaden modality coverage, and enhance both the precision and adaptability of platform-based development.
What’s Next in Platform Evolution
One of the most promising frontiers is the integration of AI and ML into platform workflows. Emerging tools can now predict critical characteristics such as expression yield, solubility, aggregation risk, and developability based solely on protein sequence. When applied during candidate selection or early process development, these insights can reduce attrition and guide more effective design choices.
CDMOs are also beginning to link early-stage platforms with commercial-scale operations via “smart” feedback loops. By capturing data across the product life cycle — from cell line selection through scale-up and tech transfer — these systems can inform adaptive process controls and continuous improvement. This evolution blurs the line between development and manufacturing and offers a path toward more holistic, end-to-end solutions.
Another key trend is the development of modular platforms tailored to increasingly complex modalities. As the field moves beyond canonical mAbs, CDMOs are designing systems that can accommodate multispecific antibodies, T cell receptor (TCR) mimetics, and antibody fragments without requiring full process reinvention. These modular approaches preserve platform speed while enabling greater molecular diversity and customization.
Toward a Multi-Platform Era
Rather than offering a single standard platform, leading CDMOs are now building multi-platform ecosystems. Depending on the product class (i.e., whether it’s a mAb, bispecific, fusion protein, or gene therapy vector) sponsors can select from a portfolio of validated systems that match their specific needs. This modularity allows more precise platform–program alignment and improves the chances of a clean fit.
At the same time, platform-based development is beginning to converge with digital CMC planning tools. Cloud-based environments that manage workflows, documentation, quality data, and regulatory strategy in real time are helping bridge functional silos and facilitate collaboration between sponsors and CDMOs. These integrated systems are particularly useful for small or virtual biotechs navigating complex pipelines with limited internal resources.
Unmet Needs
Despite these advances, several important gaps remain. Rare disease biologics, often developed with limited funding, small patient populations, and highly specific requirements, are not always well served by existing platforms. New approaches are needed that balance efficiency with the flexibility required for personalized or low-volume production.
The same is true for autologous cell therapies, mRNA-based therapeutics, and lipid nanoparticle (LNP) delivery systems. These modalities require fundamentally different manufacturing models than those used for protein therapeutics, and purpose-built platforms are still in early development. Without fit-for-purpose solutions, sponsors must often rely on fragmented, custom workflows that extend timelines and increase cost.
Finally, there is growing recognition of the need for more accessible platforms for emerging markets and smaller sponsors. The capital intensity and proprietary nature of many CDMO platforms can limit participation in biologics innovation, especially in low- and middle-income countries. Simplified, open-access, or low-cost platform options could play an important role in democratizing access to biologic drug development.
As the platform model continues to evolve, its trajectory will be shaped by the tension between standardization and customization, speed and flexibility, exclusivity and accessibility. Meeting that challenge will define the next phase of innovation in biopharmaceutical development.
Platforms as Strategic Infrastructure
CDMO-owned expression platforms have progressed far beyond their original role as technical tools for cell line development. Today, they represent strategic infrastructure — foundational systems that shape the trajectory of a biologic’s development from the earliest design decisions to commercial launch. The ability to deliver speed, reliability, and regulatory alignment makes these platforms indispensable to sponsors navigating competitive and capital-constrained environments.
For drug developers, especially small and mid-sized biotechs, success increasingly hinges on selecting not just the right CDMO partner, but the right platform. A well-matched system can accelerate timelines, reduce risk, and lay a foundation for seamless scale-up. Conversely, a mismatch — whether in terms of modality fit, customization flexibility, or long-term licensing compatibility — can delay progress and erode value.
As biologic modalities continue to expand and diversify, the most competitive CDMOs will be those that treat their platforms not as fixed offerings, but as evolving systems that adapt to scientific, regulatory, and commercial shifts. The next wave of innovation will belong to those who can deliver flexible, intelligent, and modality-specific platforms that balance standardization with the freedom to explore.