Bioengineering has benefitted biomanufacturing by creating cells with enhanced productivity and robustness. However, using a cell-line engineering approach has its challenges, among them the capability to develop clonal production cell lines and cell culture media formulations that are scalable while at the same time maintaining robust titers and the desired critical quality attributes (CQAs) needed for molecules to be successful in both the clinical and commercial setting, says Ademola Kassim, product specialist, Cell Line Development, Sartorius.

“While developing an appropriate cell line is important, a media formulation that complements a host-cell line is just as critical as it helps improve scalability and the success of the molecule,” Kassim says.

Overall, innovations in bioprocessing, including equipment and technology, aim to make scale-up of upstream processing easier. Process intensification, for instance, has been useful in improving overall upstream processing outcomes, Kassim points out.

Process intensification consists of several technologies, including single-use systems, perfusion media/feeds, scale-down models (e.g., Ambr 15/250, Sartorius), process control, and data analytics. “Overall, process intensification helps maximize the productivity of unit operations by improving drug development timelines, increasing titers, lowering costs, and reducing the manufacturing footprint. As the manufacturing footprint is reduced, this allows ‘multi-product facilities,’ thus potentially improving cost efficiencies and drug development timelines,” Kassim explains.

There remains industry focus on ways to better develop cell lines to optimize production yields at the start. Bioengineering has increasingly been focused to develop efficient cell lines for bioproduction. As an example, Kassim points out, targeted integration has been a big interest for production cell lines such as Chinese hamster ovary (CHO) cells.

“The goal of targeted integration is to engineer a cell line in which the transgene always integrates into a specific site or ‘hot spot’ of the genome. This ‘hot spot’ is a region within the genome that allows for consistently high expression and genetic stability of the biotherapeutic,” Kassim states.

Kassim also explains that, additionally, there is an increasing need to knock-out specific genes within the CHO genome by using gene-editing tools such as clustered regularly interspaced short palindromic repeats-cas9 (CRISPR/Cas9). “At times, customers see their biotherapeutic co-purifying with a specific host-cell protein (HCP) during downstream processing. If an HCP co-purifies with a therapeutic, this not only causes process-related impurity issues to arise, but also may increase immunogenicity issues,” he states.

One way that process-related impurity issues are being remedied is through the engineering of a host cell line in which potentially problematic HCPs have been knocked-out. “Once those HCPs have been knocked out, the host cell line can now be used to express the gene of interest,” says Kassim.

Engineering the cell line to knock out HCPs has several potential advantages, according to Kassim: it allows cellular resources to focus on expressing the gene of interest; it potentially reduces immunogenicity risk; and it helps for easier and cheaper downstream processing. “Other ways bioengineering can help improve productivity include engineering cells to achieve specific product quality profiles, such as afucosylation, and engineering cells to remove growth inhibitory or toxic byproducts, such as lactate,” he adds.

Kassim also explains how research has shown that the elimination of HCPs in CHO cells in some instances allows for improvements in expression levels, cell viability, and viable cell densities; however, the improvements seen may not warrant a significant reduction in bioreactor size.

“The removal of HCPs may not necessarily change the way cell culture media or feeds are formulated. However, the improvements we see in growth parameters may require a different feed regimen during a fed-batch process. Removing HCPs tends to have a bigger effect on downstream processing versus upstream processing,” Kassim says.

Other benefits to the removal of HCPs includes improved efficiencies and cost reductions during filtration and chromatography steps because fewer resources (e.g., resins, etc.) are used. “We also see scenarios where the removal of genes that produce toxic by products such as lactate occurs. In some instances, reduced production of lactate and other toxic metabolites has been found to improve growth parameters and production yield in CHO cells,” according to Kassim.

Recent research examined the effects of engineering CHO cells. In 

 (1), for instance, researchers noted that, while CHO cell expression systems have been specialized to the point where they are able to generate high concentrations of efficacious, multi-domain proteins with “human-like post translational modifications” with the appropriate product quality attributes, there nevertheless remains a need for the development of new CHO cell expression systems that can produce more challenging recombinant biotherapeutics at higher yield. Furthermore, these new expression systems are also required to produce challenging biotherapeutics with improved product quality attributes.

 researchers decided to investigate the results of engineering the lipid metabolism in CHO cells to enhance product quality attributes, an angle that had not been investigated before. Lipid metabolism became the target for this investigation because the biosynthesis of recombinant proteins is controlled in part by cellular process that are highly dependent on lipid metabolism. The researchers were able to show that, to different degrees, genes involved in lipid biosynthesis can be overexpressed in CHO cells, and they were thus able to increase the expression of a number of model secretory biopharmaceuticals by 1.5- to nine-fold. 

 concluded that manipulation of lipid metabolism in CHO cells using genetic engineering can be a new approach to enhance these cells’ ability to produce a range of different types of recombinant protein products (1).

 studied the effect of engineering CHO cells to resist hydrogen peroxide and found that hydrogen peroxide-evolved CHO cells showed improved product expression. In particular, the manufacture of bispecific antibodies using CHO cells was known to have lower yields compared to monoclonal antibodies, and it was recently shown that “reactive oxygen species” of CHO cells negatively impacted antibody production. In comparison, boosting the cells’ antioxidant capacity had a beneficial effect on the expression of recombinant proteins. 

 used directed host cell evolution to generate novel hydrogen peroxide-evolved host cells and demonstrated that the new host has a hydrogen peroxide resistance that was heritable in future cell generations (2). The new host cells also demonstrated other beneficial characteristics, such as enhanced antioxidant capacity via gene activity and improved glutathione content (which plays a role in the antioxidant defense mechanism).

 researchers were further able to demonstrate that their new evolved host cells have significantly improved recovery times following transfection, show improved growth and viability properties in a fed-batch production process, and had elevated expression of two difficult-to-express bispecific antibodies, compared to unevolved CHO host cells (used as the control). Their reported findings suggest that host cell evolution can be an important methodology for improving specific host cell characteristics, which in turn can benefit the expression of difficult-to-express biotherapeutics. The team’s data also offer insights into the role that cellular antioxidants play in the production of cell lines, supporting a growing body of research being conducted to control cellular redox and thus boost the production of recombinant proteins (2).

 demonstrated the ability to better “tune” protein translation in cells using a synthetic RNA structure. By tuning the protein translation mechanism in mammalian cells, both the yield and quality of complex proteins can conceivably be improved. The researchers developed an easy-to-implement toolbox based on the use of synthetic 5’-untranslated region (UTR) RNA structures that would facilitate the regulation of protein expression in mammalian cells. The specific benefit here is that protein expression can be regulated in a fast, reliable, and predictable manner, according to the study. The toolbox works by introducing defined RNA hairpins, which have been termed “regulation elements (RgE)”, in the 5-UTR with the aim of impacting protein translation efficiency (3).

 study also showed that RgEs can be used to characterize and optimize the recombinant production characteristics of CHO cells. What’s more, this can be done by intentionally regulating the expression of protein subunits, or by regulating the expression of a required helper factor. “Together, these elements represent an easy-to-implement and reliable toolbox for future mammalian cell line engineering applications where precise control of protein expression levels is desired to improve the cellular phenotype, but they can also be employed in the investigation of basic biological processes,” 

With such intense focus on ways to engineer cells to develop optimal cell line hosts, what does this mean for an approach that uses a cell-free method? How much progress has been made so far in moving toward a cell-free cell culture process, and does bioengineering influence a shift in that direction?

Kassim observes that, over the past few years, cell-free expression technologies have improved significantly. He notes that yields have been increased and some cell-free systems and that yields can now reach 1–2 g/L of recombinant protein. “This was mainly achieved by optimization of lysates and energy generation systems. The generation of cell-free lysates has been simplified and optimized, resulting in more potent and robust lysates with reduced batch-to-batch variability,” Kassim says.

“Bioengineering has been and will be very important for improvements in cell-free manufacturing,” he emphasizes. “Genetic engineering of host strains is essential to generate lysates with higher performance and to enable post-translational modifications.” Overall, Kassim says that improved lysate generation has decreased manufacturing costs and increased yields of cell-free expression systems, but he also notes that costs in cell-free systems are still significantly higher in comparison with cell-based manufacturing.

 57, 203–216 (January 2020).
2. R.K. Mistry, et al., 

 118 (6) 2326–2337 (2021).
3. P. Eisenhut, et al., 

Feliza Mirasol is the science editor for 


Vol. 35, No. 3
March 2022
Pages: 10–13

When referring to this article, please cite it as F. Mirasol, “Outlining Cell Lines’ Future with Engineering Approaches,” 

Articles

Cover Story

The use of bioengineering offers practical tools for the evolution of host cells.

Outlining Cell Lines’ Future with Engineering Approaches

Clinical assessment of biotherapeutics continues to be the biggest assessment to development costs of biotherapeutic products. Phase III clinical trials are particularly designed by carefully selecting the patient population to confirm the safety and efficacy. However, despite the significant developments that have happened in clinical trial design and the considerable experience that the biopharma industry has gained in the past three decades, therapeutic products continue to fail in late stage clinical trials. In this article, the authors showcase some of the monoclonal antibody (mAb) candidates that reached Phase III clinical trials but were discontinued at later stages.

The increasing importance of biotherapeutics drugs is evident as mAbs have become the predominant treatment modality for various autoimmune and cancerous diseases over the past 25 years. Major advancements in technologies have made the discovery and development of mAb therapies quicker and more efficient during these years. New drug development and approval is highly time-consuming and resource-intensive and takes an average of a decade or more to bring to market. The approximate cost of bringing a new biotherapeutic to market is an estimated $2.6 billion (including the cost of a failed mAb candidate) (1). More time and resources would have been spent into the development of a mAb candidate that later fails in late-stage trials (2). Because of this, most biopharmaceutical companies seek to identify and terminate poor drug candidates early in their development, in particular, prior to expensive, years-long Phase III clinical trials by using the “fail early, fail fast” strategy (3,4). More than half of all drug candidates will ultimately fail in Phase III trials, which are meant to be confirmatory trials (5).

Anticancer drugs are approved by the regulatory agencies on the basis of safety and efficacy, which usually needs to be demonstrated in Phase III clinical trials (6). A failure rate of 97% in oncology clinical trials is typically due to issues with drug efficacy or toxicity. Failing to understand the mechanism of action (MOA) of such cancerous drugs can lead to the mischaracterization of target-specific inhibitors, misidentification of biomarkers, and may cause interlaboratory variability between cell lines without reasonable cause (7,8). Typically, Phase III clinical trials for oncology drugs involve a large number of patients and require a substantial investment on the part of participants, investigators, and sponsors (6). Clinical data are often not reported publicly, and it is very difficult to derive the reason behind unsuccessful clinical trials. Therefore, a comprehensive understanding is required to improve the knowledge that can be used to guide further drug development in late stage. To elucidate that understanding, three cancer immunotherapy case studies are discussed here.

Rovalpituzumab tesirine (Rova-T) is a novel biomarker-specific antibody-drug conjugate (ADC) that offers a

targeted therapy for approximately 85% of small cell lung cancer (SCLC) patients whose tumors express delta-like canonical notch ligand 3 (DLL3), but the clinical dosing is limited due to off-target toxicities (9). This novel drug is being developed by StemcentRx, a division of AbbVie.

 reported a Phase I study to evaluate tolerability, pharmacokinetic (PK), preliminary anti-tumor activity, and expression of DLL3 in 29 Japanese patients. Similar PK and adverse events (AEs) were seen compared to studies in non-Japanese patients, demonstrating a manageable safety profile with promising preliminary efficacy (10). In another study, Rova-T exhibited an overall response of 44% in SCLC patients with high expression of DLL3 and who had relapsed. These patients had previously failed one or more standard therapies in Phase I/II studies (11,12). 

 performed a Phase I trial in 82 patients to assess the safety, including the maximum-dose tolerance and toxic effects. The primary activity endpoint was an objective response by intention-to-treat analysis. The trial showed a single-agent anti-tumor activity with a manageable safety profile. Significant toxicities with high DLL3 expression were reported in 10 patients out of 60 with a fixed objective response (13). 

 studied 339 patients in a Phase II study to assess safety and efficacy/objective response rate (ORR). The overall survival (OS) results in ORR were 12.4%, 14.3%, and 13.2% in all, DLL3-high, and DLL3-positive patients, respectively. Median OS was 5.6 months in all patients and 5.7 months in DLL3-high patients. Toxicity issues were observed in 63% of the patients with previously treated SCLC (14). 

 demonstrated anti-tumor activity and a favorable risk benefit in 199 Patients (14). In another comparability study of 20 patients to evaluate programmed cell death ligand 1 (PD-L1), DLL3, and enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2) expression in SCLC patients to find a candidate responder, the clinicopathological characteristics and immunohistochemical (IHC) staining intensity were compared. 

 demonstrated that one out of 20 patients (5%) exhibited positive PD-L1 expression in the metastatic lesions, as well as in the primary lung tumor. DLL3 was highly expressed in 14/20 patients (70%) and EZH2 was positive in 17/20 patients (85%) (15).

Rova-T surprisingly fell short of the mark with respect to Phase II results, which were announced in March 2018. The drug also failed to improve overall survival compared with standard chemotherapy in a Phase III trial (TAHOE) in second-line disease in December 2018 (16).

There are multiple reasons why late-stage failures occur in mAb development. These include strategic and commercial factors, lack of rigorous trial design, incomplete understanding of mode-of-action of the disease, dosing criteria, and proceeding to Phase III on the basis of poor-quality Phase II data (17,18). A well-designed PK/pharmacodynamic (PD) study with relevant biomarker and endpoint analysis can justify Phase III studies that can facilitate the drug development process (19). In many cases, public disclosures are limited for many late-stage failures, and this limits how much the industry learns from late-stage failures (17,20).

Depatuxizumab mafodotin (Depatux-M) is an ADC that specifically targets tumor cells expressing epidermal growth factor receptor (EGFR) and has demonstrated efficacy in recurrent glioblastoma multiforme (rGBM). rGBM is the most aggressive type of brain tumor that carries an extremely poor prognosis. Approximately 50% of patients exhibit tumors with EGFR amplification, thereby presenting an attractive therapeutic target (21,22).

 studied an international Phase I multicenter trial for safety and efficacy of Depatux-M plus temozolomide in patients with EGFR-amplified and rGBM (22). 

 reported on the dose response of Depatux-M in combination with temozolomide in a randomized controlled Phase II trial in recurrent EGFR-amplified rGBM (23). In 

’s multicenter Phase I study, patients received Depatux-M (0.5–1.5 mg/kg in arm B, 1.25 mg/kg in arm C) every two weeks by intravenous infusion. Depatux-M alone or in combination with temozolomide demonstrated an acceptable safety and PK profile in rGBM (24). In van den 

’s study, patients with EGFR-amplified rGBM developed ocular toxicity when treated with Depatux-M monotherapy (25).

Due to the lack of survival benefit for patients receiving Depatux-M compared with placebo when combined with temozolomide, an independent data monitoring committee recommended that the study be stopped. The randomized, placebo-controlled Phase III study was designed to evaluate the efficacy and safety. The drug had also been tested in gliosarcoma and non-small cell lung cancer (NSCLC) as well as other solid tumors, but it no longer appears in AbbVie’s pipeline (26).

Opdivo (nivolumab) is the blockbuster cancer immunotherapy drug from Bristol Myers Squibb that failed to meet the primary goal of a late-stage trial of patients with a rare type of brain cancer. The drug, when used along with the current standard of care for GBM, did not prevent the cancer from spreading when compared with the standard of care alone, concluded the Phase III “CheckMate 548” trial (27,28). Opdivo in combination with ipilimumab and chemotherapy is used to treat advanced lung cancer in adults (29). 

 reported that ipilimumab and nivolumab show significant anti-tumor activity in an increasing number of cancers. When combined, ipilimumab and nivolumab have demonstrated superior activity in patients with metastatic melanoma (CheckMate-067). A synergistic anti-tumor activity was observed in mouse MC38 and CT26 colorectal tumor models with concurrent, but not sequential CTLA-4 and PD-1 blockade (30). 

 suggested that the PD-1–blocking antibody nivolumab persists in patients 20 weeks after the last infusion. After systematic evaluation, the maximum duration that the

antibody persists on T cells or the association between this duration and residual therapeutic efficacy or potential adverse events is 20 weeks (31). The original data were from a Phase I/II trial that showed a 12% response rate for the PD-1 inhibitor, with the effect lasting a median 17.9 months. But merely two months after that regulatory win, the Phase III CheckMate-331 study found that Opdivo was no better than chemotherapy at extending patients’ lives in those who had failed one round of platinum chemo (32).

Many drug products fail in late-stage development because of inadequate efficacy or safety. Though numerous drugs enter clinical trials every year, rigorous preclinical and clinical studies are required for successful drug development. The rationale behind late-stage failures could be lack of information about the MOA or wrong choice of the patient population and dosage. The later in the clinical timeline a drug candidate fails, the more time and resources have been spent towards its development. These failures and the costs associated can be prevented to some extent by adhering to the guidelines and recommendations provided by the regulatory authorities. By considering the previous mistakes and avoiding the common problems of the trials, the prospects of a drug succeeding and being approved can be magnified. With an improved understanding of the molecular mechanisms of the disease, one would assume that Phase III failures would be a rare occurrence. However, caveats remain in the industry’s ability to use 

 and preclinical models for accurately predicting toxicity.

One of the most common inadequacies that resulted in the failure of late-stage trials, particularly of cancer drugs, was that the MOA of the product candidate was not completely understood prior to entering clinical trials. This could have been avoided by planning more accurate and stringent protein interaction studies. Also, drug targets, which were previously thought to be essential for cancer, have now been shown to be less relevant. Thus, it is quite challenging to remain abreast of the latest developments. By adhering to the principles and recommendations from the previous mistakes, it is possible to avoid these common pitfalls to increase the success in Phase III clinical trials and ultimately gain regulatory approval.

1. PhRMA, “Modernizing Drug Discovery, Development & Approval,” 

, March 31, 2016.
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, June 19, 2017.
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9. Seattle Genetics, “Seattle Genetics Discontinues Phase 3 CASCADE Trial of Vadastuximab Talirine (SGN-CD33A) in Frontline Acute Myeloid Leukemia,” Press Release, June 19, 2017.
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Anurag S. Rathore*, asrathore@biotechcmz.com, is professor and coordinator of the DBT Center of Excellence for Biopharmaceutical Technology, and Rozaleen Dash, PhD, is a postdoctoral fellow at the Center of Excellence, Biopharmaceutical Technology; both are at the Department of Chemical Engineering, Indian Institute of Technology Delhi, India.

*To whom all correspondence should be addressed.


Vol. 35, No. 3
March 2022
Pages: 14–16, 31

When referring to this article, please cite it as A.S. Rathore and R. Dash, “Late-Stage Failures of Monoclonal Antibody Biotherapeutics,” 

Special Coverage

The authors review some of the monoclonal antibody candidates that reached Phase III clinical trials but were discontinued at later stages.

Late-Stage Failures of Monoclonal Antibodies

High-concentration biologic formulations are accounting for an increasing percentage of the drug development pipeline as drug manufacturers seek to offer advanced therapeutics that can be administered by the patient or caregiver in the home setting. High concentrations, however, generally mean higher viscosities due to protein-protein interactions. Greater understanding of these interactions and the role that excipients can play in minimizing them without negatively impacting protein stability and other aspects of biologic formulations is driving a shift towards the use of carefully selected combinations of viscosity-reducing excipients.

Patient centricity driving interest in high-concentration biologics

The trend toward greater patient centricity underway prior to the COVID-19 pandemic has only been accelerated by this health crisis. There is greater interest than ever before in at-home medical care, from telehealth visits to administration of medications at home that were previously delivered in a hospital or clinic setting.

When it comes to parenteral formulations, patient preference for subcutaneous administration instead of receiving therapeutic treatments intravenously, especially for medications that require frequent dosing, is creating demand for higher-concentration biologic formulations, according to Danika Rodrigues, former drug product development scientist at Janssen R&D who is now pursuing her PhD.

That is because subcutaneous injections are limited to small volumes—traditionally 1 to at most 3 mL (1). When on-body delivery devices are employed, slightly larger volumes can be delivered over time, but even with this method, there are limits to what patients will bear. To convert an intravenous (IV) drug to one that can be delivered subcutaneously, therefore, requires an increase in concentration. This trend, Rodrigues says, is expected to continue. “Approximately one-third of all FDA-approved monoclonal antibody (mAb) products comprise high-concentration formulations (>100mg/mL), with about three-quarters of those approved since 2015,” she notes (2).

High concentrations create challenges for manufacturers and patients

The ability to deliver highly concentrated protein formulations remains a major challenge for biopharmaceutical companies, however, according to Robert Mahoney, chief scientific officer for Comera Life Sciences (formerly ReForm Biologics). Comera is focused on improving patient compliance, convenience, flexibility, and ultimately reducing patient pain and suffering through the development of a pipeline of products converted from hospital-based intravenous dosing to subcutaneous injection.

As the concentration of protein solutions increases, the viscosity also increases. Higher viscosity can make the production of biologics difficult, lead to potential quality and safety issues, and cause problems for patients.

During downstream processing, viscous protein solutions can bring challenges such as the potential for inadequate mixing and filter clogging during buffer exchange and protein concentration steps of the ultrafiltration/diafiltration (UF/DF) process, observes Laura Tanenbaum, drug product development scientist in the Biotherapeutics Development & Supply business of Janssen Research & Development. Pumping viscous solutions can also cause high shear stresses during drug product filling that can denature the protein and/or lower product recovery.

In fact, Rodrigues adds that high-concentration protein formulations typically have more stability challenges due to increased protein-protein interactions and potential for aggregation and/or opalescence. “Aggregates in the delivered product can potentially lead to decreased protein activity or unwanted immune responses in patients,” she explains. They can also potentially lead to increased formation of subvisible or visible particulates.

Some excipients may also be more prone to degradation in high-concentration protein products, Rodrigues comments. She points to polysorbates in particular, and notes that it is important that appropriate levels of such excipients be used to ensure stability.

Certain contaminants, such as host-cell proteins, from the bulk bioprocess fluid can be concentrated along with the protein during UF/DF processing, and high-concentration formulations may also carry more yellow/brown color, Rodrigues adds. “These challenges must be overcome to maintain product safety and quality,” she states. Furthermore, new analytical methods may need to be developed to assess the product quality of viscous, high-concentration formulations, according to Rodrigues.

From the patient perspective, high viscosities can limit the use of devices such as autoinjectors that may otherwise enable easier/faster administration and the potential for self-administration, according to Tanenbaum. Higher viscosities may also require injection forces too high for regular syringes to withstand and/or for some patients to achieve (3).

Protein-protein interactions are the main issue

The protein-protein interactions that can cause quality issues for high-concentration biologic solutions are the main cause of their increased viscosity. These interactions occur because the protein molecules are in greater proximity to one another. “In these crowded environments, short-range attractive interactions, including van der Waals interactions, hydrogen bonds, and dipole-dipole interactions, dominate over long-range repulsive interactions and lead to increased viscosity,” Rodrigues explains.

The specific interactions, notes Tanenbaum, depend on both the properties of the individual protein and the formulation. “Some molecules may have more solvent-exposed hydrophobic patches that permit more of these short-range attractions, resulting in solutions with higher viscosities, while molecules with hydrophobic patches that are more hidden may not have this same viscosity concern,” she says. Furthermore, Tanenbaum observes that formulation pH can alter the overall charge of the protein, with pH values closer to the isoelectric point potentially causing increased viscosity.

Typically, formulations with protein concentrations below 75 mg/mL do not have viscosity issues (4). Some but not all proteins at concentrations of 100 to 200 mg/mL will exhibit measurable increases in viscosity. When concentrations surpass 200 mg/mL, most if not all protein solutions have higher viscosities simply due to the forced physical closeness of the protein molecules.

The patient experience of a subcutaneous injection does not depend solely on the formulation viscosity. The size and length of the needle, the diameter of the syringe barrel, and the injection rate also determine the injection force. The insertion rate of the needle, the temperature and pH of the product, and the stress level of the patient are additional factors.

Formulators cannot control many of these factors, but they can minimize their importance by, when possible, reducing the viscosity of high-concentration formulations using appropriate excipients. The key to effective excipient use, Tanenbaum underscores, is understanding protein-excipient interactions.

Salts and amino acids have been used as viscosity reducers. One proposed mechanism of action, according to Tanenbaum, is the binding of charged excipients at protein hot spots such that the presence of that excipient disrupts protein-protein interactions that would otherwise lead to increased viscosity.

“Different protein molecules have varied numbers of ‘high-affinity’ binding sites for specific excipients, which can lead to different levels of viscosity modulation,” Rodrigues notes. For that reason, she says that while it is generally favorable to minimize the total number of excipients in a given formulation, there may be cases where combinations of excipients provide synergistic effects. “Researchers across the biopharma value chain continue to work and innovate in this space, including novel excipients and excipient combinations,” adds Tanenbaum.

There are some limitations with current excipients

There are limitations to what excipients can achieve with respect to viscosity reduction, in part because of how they function and the protein-specific nature of viscosity changes with concentration. “There is still a limit to the amount that viscosity can be reduced through addition of excipients, as viscosity increases exponentially as a function of protein concentration,” states Rodrigues.

One of the challenges with using excipients is their potential to impact protein stability. “The mechanism by which the excipients interact with proteins to lower their viscosity can also change the conformations of the proteins,” Rodrigues explains. “While increasing excipient concentration could further lower the formulation viscosity through interference of protein-protein interactions, it could potentially act as a protein destabilizer simultaneously; thus, it can be important to balance viscosity-reducing and protein-stabilizing capabilities during excipient selection,” she concludes.

Osmolality must also be monitored, according to Tanenbaum, because the addition of excipients to protein formulations may increase this property, which should ideally be kept near isotonic conditions. The effect of excipients is also dependent on the pH of the formulation, she comments.

During UF/DF processes, meanwhile, the addition of excipients to a protein formulation can cause the effective excipient concentration and formulation pH to be shifted from the target conditions due to the retention of charge (from the protein) on a particular side of the UF/DF membrane or steric limitations associated with a high number of protein molecules in a given volume, says Tanenbaum. “It is important in order to understand the molecule and the formulation space, to specifically evaluate each excipient and excipient concentration and the impacts they have,” she contends.

It is also important, observe Rodrigues, to be aware that the magnitude of viscosity reduction is a protein-specific phenomenon, as some proteins maintain relatively low viscosities at high concentrations without the need for added excipients, whereas others may have high viscosity despite the addition of excipients. “Although much effort is spent on reducing the viscosity of formulations to develop high-concentration products, lowering the viscosity with the addition of excipients may not necessarily mean that we can achieve higher protein concentrations in the concentrating process due to protein solubility limits,” she emphasizes.

One recent approach to overcoming these challenges has been to investigate the impact of different excipients individually and in combination with one another. Two companies active in this area have been Comera Life Sciences and MilliporeSigma.

Comera Life Sciences has identified caffeine as an excipient to be used alone or in combination with secondary excipients to significantly reduce the viscosity of highly concentrated therapeutic protein solutions (5). It has also developed antibody formulations using this compound to significantly enhance viscosity reduction (6). Comera has established individual agreements with Astellas Pharma Inc., Bayer AG, and KBI Biopharma, Inc. to enhance formulations of biologics based on Comera’s patented technology (5).

In February 2020, Comera Life Sciences also entered into a global licensing and collaboration agreement with MilliporeSigma to commercialize Comera’s excipients used in biotherapeutic formulations (7). That agreement has since been completed.

MilliporeSigma separately identified suitable excipient combinations for viscosity reduction and launched its Viscosity Reduction Platform of patented excipients and excipient combinations designed to reduce viscosity while maintaining protein stability in October 2021 (7). The Platform is based on six excipients that are intended to be used in up to nine different combinations, always including one amino acid and one anionic excipient, the latter of which are the ones most likely to negatively impact protein stability (7). Using these combinations results in more efficient viscosity lowering and enables formulators to better maintain protein stability while achieving viscosity reduction.

Importantly, all of the excipients in MilliporeSigma’s Viscosity Reduction Platform have been used in parenteral formulations in the past as parenteral nutrition agents (considered by the company to be APIs), counter ions to APIs, or for pH adjustment (8). They have all been subjected to the Hen’s Egg Test–Chorioallantoic Membrane (HET-CAM) in-vitro skin irritancy test with no irritancy detected. A formal toxicological and safety evaluation has also been performed by a European registered toxicologist.

At Janssen, formulation approaches can rely on historical knowledge, computational modeling, and high throughput experimental techniques to identify promising excipients for viscosity reduction, according to Tanenbaum. “The optimized excipient or combination is highly protein-specific and must be evaluated on a case-by-case basis to ensure stability in the final
formulation,” she says. Once promising excipients or combinations are identified, the required concentration of the excipient can be further refined.

However, Tanenbaum also recognizes that currently all FDA-approved high-concentration products use excipients that have been traditionally employed due to regulatory challenges with using a novel excipient.

“There is a lot of exciting research and progress ongoing in this area to enable patient-centric drug product development. We recognize that not all excipients alter viscosity in the same way across different protein molecules nor across protein concentrations of a single molecule, which drives the need for product-specific formulation. Furthermore, lowering the viscosity through the addition of some excipients does not necessarily permit the ability to achieve high or ultra-high concentrations of the protein formulation. There is consequently a need for novel excipient solutions and a means for enabling their use in drug formulations,” Tanenbaum believes.

For that reason, Janssen is involved with the recently launched FDA “Novel Excipient Review Pilot Program,” which Tanenbaum says could encourage excipient manufacturers and pharmaceutical companies to explore novel excipients in formulations for viscosity reduction and other formulation purposes.

 36, 2986-2996 (2019).
2. S. Shouye Wang, Y. (Susie) Yan, K. Ho, 

, 4 (4) 262–272 (October 2021).
3. R. P. Watt, H. Khatri, and A. R.G, Dibble, 

 Jan 10 554:376-386 (2019).
4. S. Braun, et al., “The Viscosity Reduction Platform: Viscosity-reducing excipients for protein formulation,” MilliporeSigma White Paper, 2021.
5. ReForm Biologics, “ReForm Biologics Announces Issuance of U.S. Patent on Additional Excipients for Therapeutic Protein Formulations,” Press Release, Nov. 20, 2019.
6. Yuhong Zeng, et al., 

 110, 3594-3604 (2021).
7. BioPharm International Editors, “MilliporeSigma and ReForm Collaborate on Excipient Commercialization,” 

, Feb. 12, 2020.
8. BioPharm International Editors, “MilliporeSigma Launches Excipient Platform for Protein-Based Therapies,” 

Cynthia A. Challener, PhD, is a contributing editor to 


Vol. 35, No. 3
March 2022
Pages: 17–20, 37

When referring to this article, please cite it as C. Challener, “Excipients for High-Concentration Biologics,” 

Development

Careful selection is essential for achieving viscosity reduction without protein destabilization.

Excipients for High-Concentration Biologics

A treatment that has been top-of-mind in recent years is cell and gene therapies (CGTs). Many companies and organizations investigate the potential of this type of treatment to address unmet medical needs. While significant headway has been made, CGTs are in their infancy. But with the potential to cure diseases, CGTs could change the future of treatments for certain conditions.

“[CGTs] offer for the first time the possibility to offer truly disease-modifying treatments, providing options for conditions considered intractable or where the current standard of care is insufficient,” says Bayer AG company sources.

While headway has been made for CGTs, there is still much to consider for how manufacturing can be improved, which ultimately impacts the success of a drug product.

“Safety and efficacy of CGTs are strongly determined by production process quality,” says Bayer AG company sources. “Therefore, robust manufacturing processes are a fundamental factor for their success. Scalability and optimizing chemistry, manufacturing, and control [CMC] processes from preclinical research to early usage and ultimately full-scale commercialization remain critical aspects in the translation of these technologies to tangible treatments.”

What’s next for CGTs? Where has the industry made headway, and what challenges are still ahead? Moreover, what potential trends are on the horizon?

 interviewed Elena Meurer, principal consultant, Biopharma Excellence, a Pharmalex company; Mathew Durdy, CEO, Cell and Gene Therapy Catapult; Matthew Hewitt, executive director scientific services, cell and gene therapy, Charles River; Emily Moran, vice president, viral vector manufacturing, The Center for Breakthrough Medicines; Chris Xu, CEO, Thermogenesis; and David Chang, CEO of WuXi ATU about challenges, breakthroughs, and trends in manufacturing CGTs.

: What are the biggest challenges for manufacturing CGTs?

One of the serious challenges is the affordability of cell and gene therapies for the healthcare system and for patients. Manufacturing costs often contribute significantly to the high price, although continuous efforts are being made to reduce these costs via improved manufacturing technology. Typical reasons for high manufacturing costs are the need for flexibility in the manufacturing schedule, scale limitations, expensive quality control, and complex logistics.

We need to look at [the] manufacturing of CGTs in the full context of what it takes to deliver [the] manufacturing of these therapies in order to identify key challenges. Skills, supply chain issues, and access to flexible manufacturing capacity to meet patient and clinical timelines, as well as automation/digitization of documentation for batch release are some of the challenges that need to be addressed to enable these therapies to reach patients in an efficient way and at scale.

: A pain point more relevant for autologous cell therapies is how to efficiently manufacture them to minimize vein-to-vein times. Currently, companies are employing a centralized manufacturing approach, which is possible in the short term as the current slate of commercial therapies addresses small patient populations. Even so, there have been issues with this current model. A 2021 European Hematology Association conference poster described how vein-to-vein times can vary significantly when commercial cell therapies are manufactured far from the point of care (1). From this, a question arises whether autologous cell therapy manufacturing needs to migrate to a decentralized manufacturing model to reduce vein-to-vein times.

Moran (The Center for Breakthrough Medicines):

 Current therapeutic platforms are nascent, developed in academic labs, challenged by the ability to efficiently scale, replicate, and effectively manufacture their therapies. While the science behind these platforms will need to change over time, regulators need to keep pace. Close collaboration with regulators is required to develop a path to approval. Manufacturing solutions for advanced therapies require seamless and robust tech transfer processes to avoid delays in process development and inefficient scale-up models; this is a current gap that needs to be addressed.

The process is very lengthy with storage and harvesting having to yield to certain standards. There are not a lot of CDMOs [contract development and manufacturing organizations] that are well-equipped to handle the process that is required for cell and gene therapy manufacturing, and it takes years for a company to build their own, shall we say, formula of manufacturing. This leads to a shortage of CDMOs.

 One of the biggest challenges still facing the cell and gene therapy industry is plasmid supply. There are often long lead times associated with GMP [good manufacturing practice] plasmid production; so, it can be very advantageous for a therapeutics developer to work with a manufacturing partner who can not only manufacture their viral vectors, but also their GMP-grade plasmids, and can supply these in the shortest possible timeframe. There’s also variability in plasmid quality, which can impact the titer and quality of the resulting viral vector.

What are significant breakthroughs for manufacturing CGTs?

The first human patient to be treated with gene therapy was a four-year-old girl suffering from severe combined immunodeficiency in 1990 (2). She received treatment for a congenital disease called adenosine deaminase (ADA). Since then, gene therapies have been used to treat diseases, such as cancer, cystic fibrosis, and hemophilia. In 2017, the FDA gave its first approval of a gene therapy called Luxturna, which is used to treat patients with established genetic vision loss that may result in blindness (3). Gene therapies are still being studied and developed, with over 1000 clinical trials currently underway.

 CRISPR [clustered regularly interspaced short palindromic repeats] technology presented us with the opportunity to rewrite our genetic code, and for the last 20 years, the vision has been to bring this into the clinical phase and make it possible to alter genetic abnormalities in vivo. That vision is now extremely close to becoming a reality. But of course, it’s not just CRISPR technology that has reached this point, but viral vector engineering, too, to ensure specific packaging of CRISPR and Cas9 within AAV [adeno-associated virus] vectors for delivery to the target tissues.

Gene editing has the potential to transform cell therapy manufacturing, making it truly personalized and flexible. Manufacturing GMP plasmid and vector is a time-consuming, expensive process. Moving to gene editing could significantly simplify cell and gene therapy manufacturing while reducing costs. The use of gene editing also provides the ability to target specific sequences for knock-out and specific loci for knock-in. Future cell therapies may be manufactured at the point of care to address specific patient indications using advanced analytics data to identify the specific edit sites and/or antigens required to eliminate tumor cells.

 [T]he use of iPS [induced pluripotent stem cells] in the manufacturing of allogeneic therapeutics is an important milestone. Even though there are still many constraints regarding [the] large-scale production of iPS cells, it is just a question of time before the manufacturing technology catches up.

 The development of CAR T-cell [chimeric antigen receptor T-cell] technology and approval of those [have] opened the way to many clinical trials and therapies now in the clinics. Industry, regulators, payers, healthcare providers, and national healthcare systems have all [learned] a lot from CAR T-cell therapies, reaching patients both from manufacturing requirements as well as [from a] health, economics, regulatory, and supply chain perspective. The manufacturing and administration of living therapies that have the potential to cure diseases [have] triggered a complete shift in how therapies should be evaluated.

Moran (The Center for Breakthrough Medicines)

: The significant breakthroughs include process automation that is fully integrated with equipment, closed disposable systems for a variety of processes, and flexible facility design with a modular approach. Building on these foundational needs will allow manufacturers to flex and support different platforms such as plasmids, viral and non-viral vectors, and autologous and allogeneic cell therapies. This can be further expanded to in-line analytics, to meet the ever-evolving demand.

What trends are you seeing in the CGT space?

 Therapeutic developers have been watching the field and [have] seen that [CMC] issues have been the focus of many regulatory delays. Because of this, we’ve seen a renewed focus on ensuring analytical methods are able to be implemented for commercial products. The regulators have been clear they will require analytical methods that are able to consistently measure product critical quality attributes (CQAs). Certain cell therapy modalities are more difficult than others when doing this development, such as unmodified tumor-infiltrating lymphocytes (TILs), to identify reliable cell characterization and mechanism of action (MoA) potency/functionality assays. Even [with] this, many are making progress.

It is encouraging to see that there [are] now more upfront thoughts about data and data handling. The implementation of comprehensive manufacturing execution systems and integrated digital systems is traditionally embarked upon in readiness for commercialization once the manufacturing process is completely tied down and just requires churning out the same process over and over again. In CGTs, it is being embarked upon earlier and earlier in the phase of clinical development; it is not unusual for an MES [manufacturing execution system] to be considered in Phase I.

 Manufacturing facility design is evolving to accommodate [the] flexibility required to address shifting needs in the marketplace. Manufacturing facilities will need to be flexible multi-product facilities that can manufacture a variety of advanced therapeutics. There will be more exploration into non-viral delivery methods and more patient-focused processes, requiring a greater level of adaptation than ever before. Improved tropism, vector and capsid design, and delivery mechanisms will have a dramatic impact on the field as well as better production methods that result in higher yield in both upstream and downstream.

 In the past, traditional chemical or small-molecule drugs were made for millions or billions of people. Cell and gene therapies are personalized drugs, using your own cells, and are specifically made for each individual … Current infrastructure only can handle thousands of patients. We need infrastructure for cell and gene therapy that can potentially handle millions and hundreds of millions of patients. The investment in cell and gene
manufacturing infrastructure capabilities will increase dramatically.

: Enormous progress has been made in the application of CRISPR and gene-delivery technologies. One of the trends we’re seeing is the combination of different technologies such as CRISPR, viral and non-viral gene delivery, and the potential of CAR-T and CAR-NK applications for creating powerful therapeutic approaches. Progress in RNA-based gene delivery and transposon technology should not be underestimated either. Different gene modification and delivery tools are often used together.

The [CGT] industry is expanding rapidly, with emerging trends that can best be described as either therapeutic or process-based. Therapeutic advances, such as in vivo gene editing, were unheard of a few years ago, but some in vivo CRISPR/Cas9 therapeutics are now in the clinical phase. The growing preference for allogeneic over autologous cell therapies—including allogeneic CAR T-cell therapies—is another notable therapeutic trend. As for process-based trends, there’s an increasing focus within cell and gene therapy to improve the scalability of manufacturing processes and reduce the costs associated with manufacturing. A similar focus is being paid within viral vector engineering and other production technologies to improve the quality of viral vectors in terms of packaging efficiency, infectivity, and even specificity for a target cell type.

S. Fried et al., “Patients With Out of Specification Tisagenlecleucel Can Be Salvaged With Point-of-Care CART-T Cells: An Observational Intention-to-Treat Single-Center Analysis,” presentation at 2021 European Hematology Association Virtual Conference, EHA (Virtual, Aug. 15, 2021).

FDA, “FDA Approves Novel Gene Therapy to Treat Patients with a Rare Form of Inherited Vision Loss,” 

When referring to this article, please cite it as M. Rivers, “Opportunities for Growth and Breakthroughs for Cell and Gene Therapies,” 

Manufacturing

CGTs offer hope for the future of treatments, but the costly manufacturing, slow turnaround time, and need for supplies hinder progress.

Opportunities for Growth and Breakthroughs for Cell and Gene Therapies

Blow-fill-seal (BFS) equipment has been widely used for many years in aseptic fill/finish of small-molecule and biologic liquid formulations, including nebulizer solutions for respiratory delivery and ophthalmic sterile solutions packaged as unit-doses. A key advantage of the process is that it is a closed, automated system—a plastic container is formed within the equipment, filled with sterile solution, and closed, with limited human intervention. Although concerns about process temperatures caused hesitancy with some manufacturers of temperature-sensitive biologic drug products, understanding and control of these issues has significantly increased. As a result, more manufacturers are considering BFS as an option for fill/finish of vaccines and other biologic drug products, including large-volume and small-volume parenteral injectable drug products.

In addition to being an efficient, closed aseptic system, another benefit of the BFS process is the ability to handle unique or complex containers that can be designed for a specific need. For example, GlaxoSmithKline’s (GSK) oral rotavirus vaccine in unit-dose BFS containers was designed in collaboration with global health organization PATH and used for the first time in February 2020 in an immunization program in Myanmar (1). The container is formed as five single doses in a connected pack of tubes that can be separated for individual oral delivery. The container was designed to be less bulky than conventional vaccine squeeze tubes, which makes it easier to transport and store and reduces cold-chain costs.

“The container in a BFS process can be designed to be functional for delivery to the patient,” says Andy Goll, president of Weiler Engineering, Inc., which designs and supplies BFS equipment as well as using the equipment for fill/finish as a contract development and manufacturing organization (CDMO). “For oral delivery to young children, for example, the GSK rotavirus vaccine container was designed with a longer, narrow tube for the opening so that it would fit well inside the child’s cheek. Containers for injectable vaccines can be designed to fit to a separate needle hub.”

“Some of the benefits of BFS aseptic packaging include limited human intervention on the filling line, efficient production of unit-dose containers at high volumes, ability to rapidly scale production for surge capacity, and a consolidated materials supply chain that helps decrease reliance on external sources,” says Josh Myers, senior director, Supply Chain, ApiJect.

“Single-dose containers reduce the wastage found in multi-dose glass formats commonly used with vaccines,” adds Tim Kram, managing director at BFS equipment manufacturer Rommelag Engineering. “BFS systems are compatible with disposable filling systems, which minimize product loss during filling.” The most significant benefit, says Kram, is having a fully automated system, which reduces risks in the aseptic process.

BFS reduces the risk of microbial and foreign particulate contamination when compared to traditional glass vial fill/finish processes, adds Waiken Wong, manager of Development Engineering at CDMO Woodstock Sterile Solutions.

In the BFS process, the plastic raw material is melted, extruded into a cylindrical tube (called a parison), and formed into a container by blowing sterile air or nitrogen into the tube to force the plastic into the shape of the mold. Cooling of the container begins within seconds after it is formed, because the mold is chilled. The drug solution is then filled into the just-formed plastic container while still inside the mold, and the container is sealed. The form, fill, and seal steps typically take less than 15 seconds.

“Essentially, you have to manage process parameters to cool the container before the drug product contacts the internal surface,” explains Goll. “There are multiple ways to control the container temperature by controlling the cooling and blowing process. Not having to worry about heat degrading a vaccine is a game-changer in the ability to use BFS.”

Polymers typically used in BFS containers are low-density polyethylene (LDPE), high-density polyethylene (HDPE), and polypropylene (PP). “LDPE is typically used for containers for large-molecule drugs or vaccines, because it can be extruded at a lower temperature than HDPE or PP. A lower processing temperature makes it easier to obtain an appropriate surface temperature for filling,” explains Goll. PP would be used for drugs that require terminal sterilization, as it can withstand higher temperatures during the terminal sterilization process.

Goll says that interest in BFS for fill/finish is rising as manufacturers recognize its potential, particularly for the flexibility of the types of containers that can be filled. Weiler is performing feasibility studies for potential users who want to switch from a conventionally filled glass container to a BFS plastic container. The first step, he explains, is to check compatibility of the drug product and the container, including evaluating the extractables and leachables and product stability, typically using accelerated stability studies. Next, the container shape, including its opening, closure, and any separate adapters, is designed and a mold is made for the specific container shape. In the subsequent engineering design phase, the equipment and the process are optimized for the product. An advantage of the Weiler carriage (i.e., shuttle) system is the flexibility to easily change the mold size or shape, although it is not as high speed as a rotary BFS equipment setup, says Goll.

“Biomolecules can have some affinity for olefinic [LDPE, HDPE, and PP] materials, so stability studies are needed to ensure adsorption or absorption effects don’t impact therapeutic dose or activity levels,” adds Wong. Effects from gas and water vapor permeation through the walls of BFS containers may also need to be assessed in a stability program. Both standalone and comparative stability studies with glass are needed to demonstrate that plastic is an acceptable alternative.

“Many of the challenges a drug product developer faces when considering BFS are the same for traditional filling lines, such as glass vials,” adds Myers. “What is most important to remember, regardless of filling process, is that careful evaluation and grasp of the key parameters and process characteristics will allow for appropriate selection and risk mitigation.”

Temperature is one aspect that includes not only temperatures during filling, but also in mixing prior to filling and in post-filling activities. All materials that the drug product will come into contact with should be reviewed, along with cleaning procedures and transportation and storage of raw materials and finished products, says Myers. Modes of sterilization, heat mitigation, and protecting oxygen and light sensitive drugs all need to be considered. For plastic containers, foil wraps are often used to reduce exposure to UV light and oxygen and to reduce any potential vapor loss, adds Myers.

Kram adds that there are two primary methods to keep the product cool while using BFS technology. “The first does the most work, keeping the product at a low temperature (e.g., 2–5 °C) while in the batch holding tank, and controlling the temperature from the tank to the point of fill. By prechilling the product the final temperature can be kept in an acceptable range,” he explains. The second method is through container design.

Woodstock Sterile Solutions, which is the new name of the former Catalent BFS CDMO business that was acquired by a private investment firm in 2021 (2), was granted a US patent for a new, “cold” BFS process (3) that builds on its 50-year experience with using BFS for filling respiratory, ophthalmic, topical, otic, and oral drugs. The new process is designed to minimize the impact of temperature on thermally sensitive molecules.

“Our cold system comprises a combination of optimized process parameters that together reduce the exposure of the drug product to potentially detrimental temperatures,” explains Wong. “These parameters are from points throughout the manufacturing process, from the bulk product in the holding tank to the final sealing of the BFS container. The goal is to optimize the conditions to provide the best level of control.”

Wong says that the process has been evaluated for filling a monoclonal antibody and in exploratory studies for vaccines. He says that multiple programs, ranging from early- to late-stage clinical, are using the process.

As BFS expands into more biologic drug products and vaccines, the opportunity is opening up for new delivery systems. Packaging an injectable product with a BFS process in a plastic ampoule is not new. What is new, however, is ApiJect’s prefilled injector that connects an intramuscular needle hub to a BFS single-dose container. In this case, the fit of the needle hub onto the container to make the complete drug delivery system must also be considered, says Myers. When filling an injectable drug product, there may be additional requirements for the biosafety level of the environment and visual inspection, adds Myers.

The prefilled injector technology in development by ApiJect is designed to be a cost-effective drug delivery system to manufacture and be lightweight for lower transportation costs. The single-dose format has advantages for safety, sterility, and low waste, which are especially important in low-resource, developing regions (4). While the drug delivery system was developed prior to the COVID-19 pandemic, the concept of being able to produce prefilled syringes on demand was seen as a potential solution to the concerns about possible vaccine container shortages in the midst of the pandemic in 2020, and the US Department of Defense awarded a contract to ApiJect to expand US production capability of up to 45 million doses per month in Biosafety Level 2 cleanrooms at The Ritedose Corporation in Columbia, SC (5). Although the emergency fill/finish capability in the United States was prepared in 2020, it did not end up being used for COVID-19 vaccine filling as the device has not been cleared by FDA. The technology, however, is available for drug manufacturers to evaluate.

Today, ApiJect continues to have operation capacity for development and commercial work at The Ritedose facility. In addition, in December 2021, French CDMO Fareva and ApiJect announced a 10-year licensing agreement to install BFS production lines with the capacity to fill/finish 500 million doses per year of vaccines and other large-molecule injectable drugs with ApiJect’s technology (6). BFS machines from Rommelag in Germany will be installed in Biosafety Level 2 cleanrooms. Fareva and ApiJect plan to produce validation batches in 2022. This type of “distributed fill/finish” capability aims to strengthen local supply chains.

1. PATH, “Myanamar’s Rotavirus Vaccine Campaign First to Use New Delivery Technology,” 

2. SK Capital, “SK Capital Closes Acquisition of Catalent’s Blow-Fill-Seal Sterile CDMO Business and Changes Name to Woodstock Sterile Solutions,” Press Release, March 31, 2021.

3. Woodstock Sterile Solutions, “Woodstock Sterile Solutions Granted US Patent for Cold Blow-Fill-Seal Packaging System and Process,” Press Release, Dec. 9, 2021.

4. ApiJect, “A New Way to Inject and Track Vaccines that Can Reach Everyone” 

5. DOD, “DOD Awards $138 Million Contract Enabling Prefilled Syringes for Future COVID-19 Vaccine,” Press Release, May 12, 2020.

The continuous, aseptic fill/finish process is finding use in vaccines and biologic drugs. 

BioPharm International, March 2022 Issue

Outlining Cell Lines’ Future with Engineering Approaches

Late-Stage Failures of Monoclonal Antibodies

Excipients for High-Concentration Biologics

Opportunities for Growth and Breakthroughs for Cell and Gene Therapies

Considering Blow-Fill-Seal for Biologic Drugs

Considering Purification and Separation in the Downstream Train

Empowering Protein Characterization

Selecting and Optimizing the Right Manufacturing Partner

A Rocky Road Ahead for Commissioner Califf

Characterizing the Unseen Drama of Analytics

The Importance of Batch Record Reviews During Audits

Locating Logic in Pharma Manufacturing