Despite their track record of demonstrating significant therapeutic efficacy, biologics still face daunting challenges in their drug delivery. Biologics such as monoclonal antibodies (mAbs) and some vaccines are largely administered via injection or by infusion. These methods can often be a barrier to patient compliance. Less invasive forms of biologic drug delivery are in development, particularly oral administration and inhalation routes.

The current rapid rate of new drug target discoveries, coupled with increasingly effective engineering processes and a growing knowledge and understanding of how biologics are processed in the body have resulted in a higher number of biologics in clinical development and approved for the market. However, to date, formulations of biologics have mostly been designed for the parenteral route of administration. Because of this design, many biologics have short plasma half-lives which require frequent administration. The need to use needles on a frequent basis leads to sometimes painful administration and ultimately poor patient compliance (1).

Frank Tagliaferri, PhD, chief scientific officer at Pace Life Sciences, emphasizes that biologics are typically larger molecules with more structural requirements as opposed to small-molecule therapeutics. The latter has long dominated the traditional oral route of delivery. Biologics also encounter more structural sensitivities that need to be overcome, Tagliaferri says.

“These limitations often result in poor bioavailability for a variety of reasons, including degradation while in the alimentary tract, inability to overcome intestinal cell or mucosal barriers, and first-pass metabolism, which is avoided with the traditional injection routes,” Tagliaferri explains. He further adds that, “While there may be beneficial solutions to these hurdles individually, it is a significant challenge to overcome all of them with what will generally be a higher-cost biologic drug where extremely low bioavailability is not always economically feasible.”

Today, alternative biologics drug delivery methods that have shown promise include inhaled biologics and oral solid biologics. Past-case scenarios include inhaled insulins. As Tagliaferri notes, “the utility of inhaled biologics showed some promise during the development of both the Pfizer and Mankind inhaled insulin products, where numerous technical hurdles for lung delivery were overcome. But the lack of a commercial success to date demonstrates that issues such as ergonomics, patient-to-patient variability, and high cost of goods all contribute to public acceptance and the ultimate success of an alternate route” (2,3).

Oral solid biologics, on the other hand, possess different, but just as significant, challenges compared to inhaled biologics, Tagliaferri says. Yet, there appears to have been more significant progress in oral solid biologics, he avers. “The small-molecule development history has provided several delivery enhancements to oral delivery that have been successfully applied to a limited number of biologics. These include techniques such as enteric coating of capsules, additives to control release and residence time in the gut, [and] physical formulation techniques such as spray drying or lyophilization designed to help stabilize the molecules,” Tagliaferri explains. “When we combine these techniques with advancements in the use of additives to protect molecules or enhance delivery such as polymers, penetration enhancers, chelating agents, etc., there has been success as demonstrated in the delivery of some metabolic enzymes to the gut using spray dried proteins and enterically coated capsules.”

Tagliaferri also observes that there does not seem to be a universal “needle-fee” path for all biologics. Rather, depending on the molecule, dose, and intended site of action, current alternative options such as inhaled, nasal, transdermal, buccal, oral, etc., would all have some utility in the market. “Due to its convenience, compliance, and overall acceptance, however, the oral route will continue to be aggressively pursued and—with emphasis on future particle engineering or novel excipient advancements—may eventually be achieved,” he says.

At a 2022 Oxford Global conference on formulation and delivery (4), speakers discussed how the field of inhaled biologics had reached an interesting phase of development. Speakers noted how scientists are currently working on optimizing the process by focusing on methods that reduce the necessary dose needed to be effective and delivering the biologic to the site of action. They point to one example in which researchers are working toward more specific delivery to target organs in the body, such as cancer cells in the lungs, rather than the conventional treatment which targets the whole body via injection. However, developing an inhaled biologics formulation for this case scenario, and others, requires overcoming the issues inherent with creating stable and safe formulations for biologics (4).

Much work is currently going into developing biologics formulations that can be inhaled to deliver therapy locally to the lungs for treating respiratory diseases, according to speakers at the 2022 conference. The work has led to innovations that include antisense oligonucleotides, messenger RNA (mRNA), and lipid nanoparticles (LNPs), the speakers noted (4). The speakers also noted that the recent interest in developing inhaled and nasal biologics was partly spurred by the urgency seen during the development of COVID-19 vaccines and treatments for other viral pathogens (4).

Meanwhile, more progress was made on oral vaccines with the completion in 2023 of a Phase I clinical trial for an oral vaccine platform known as QYNDR, which is a self-administered drinkable vaccine, reportedly the first of its kind, according to US Specialty Formulations, a manufacturer of sterile injectable, topical, and specialty pharmaceuticals (5).

QYNDR, a next-generation protein-based oral vaccine (mucosal vaccine), was developed as a means to addresses challenges seen with current COVID-19 vaccines. In the results from the Phase I clinical trial, the vaccine demonstrated longevity and cross-variant protection from multiple COVID-19 strains. The study may have also possibly identified a correlation of protection against the virus and other strains, which the company will be further investigating in a Phase II clinical trial (5).

“The [P]hase I clinical data showed strong evidence that this oral platform and vaccine is a revolutionary industry disruptor and will become the preferred method of vaccination in the future,” said Kyle Flanigan, CEO of USSF, in a press release issued at the time that the Phase I trial was completed. “As we proceed into Phase II and III, we are confident this next-generation vaccine will be more effective than other mucosal vaccines in current development and testing” (5).

Meanwhile research is also being done that considers other alternative routes to biologics administration besides the inhaled route or oral route, or the conventional parenteral route.

“While purely topical biologics will likely have limited utility due to the significant barrier posed by the skin, there has been significant work in the transdermal delivery of biologics, particularly around insulin,” says Tagliaferri. “Physical skin perturbation techniques ranging from microneedles, microporation, sonophoresis, iontophoresis, and even jet injection have all shown some utility for delivering primarily smaller proteins or peptides, and especially vaccines where dose requirements are frequently very low.”

However, the challenges to a topical route of administration again revolves around getting the biologic through the stratum corneum barrier of the skin and into microcirculation, while remaining intact, Tagliaferri explains. “Since a number of these transdermal techniques require time to realize the sufficient diffusion through the skin, the stability of the payload is a factor along with accessing sufficient surface area to allow diffusion of the required dose,” he says.

Market potential for alternative drug delivery routes for biologics is substantial. For the inhalation contract development and manufacturing organization (CDMO) market, the market size has seen strong growth in recent years and is expected to see a compound annual growth rate (CAGR) of 7.1% year-over-year, increasing from $1.94 billion in 2023 to $2.08 billion in 2024 (6). This growth is attributed to a rising prevalence of respiratory disorders as well as growing demand for personalized medicine, both of which are expected to lead to an increase in outsourcing by pharmaceutical companies and growth of the biopharmaceutical industry (6).

Further growth in the inhalation CDMO market size is expected in the next few years, growing at 6.8% CAGR to $2.7 billion in 2028. This forecasted growth is attributed to several factors, such as a focus on precision medicine and targeted therapies, an expected rapid expansion of biopharmaceutical inhalation therapies, increasing emphasis on patient-centric solutions, global market expansion, and opportunities that are expected to emerge in new markets (6).

Meanwhile, future market potential for biologics in general is on a strong trajectory, while the possible potential for inhaled biologic formulations for a market such as asthma, for example, is ripe. For one, regulatory bodies are hastening the approval of biologics, especially for respiratory disorders, and secondly, many conventional biologics that have been approved to treat asthma have a favorable profile because they offer specific and precise treatment of asthma symptoms. Finally, rising awareness among healthcare providers of these favorable profiles for asthma treatment using (conventional) biologics is driving healthcare providers to increasingly include a biologics treatment in their asthma healthcare regimen for patients (7).

The global asthma biologics market was estimated at $6.5 billion in 2022. Growth of the market is projected to increase at a CAGR of 12.5% from 2023 to 2031 and is expected to reach more than $19.2 billion by the end of 2031 (7).

Biologics are particularly used to treat severe cases of asthma that are otherwise difficult to treat with conventional inhaled medicines. Asthma-treating biologics assist in enhancing lung function, which lessens the dependence on oral corticosteroids while reducing the severity of asthma symptoms. Biologics that have been approved for treating asthma typically focus on several processes related to the disease, including inflammation, allergic reaction, and airway remodeling (7).

These biologics target pathways that lead to lung inflammation, which minimizes asthma attacks, alleviates symptoms, and reduces dependency on steroids. However, asthma-related biologics are routinely administered via injection or by infusion in hospitals; although, some biologics can be self-injected by the patient at home. FDA-approved biologics for treating asthma include omalizumab (anti-immunoglobulin E treatment), mepolizumab (anti-interleukin-5 [IL-5]), resiluzumab (anti-IL-5), benralizumab (anti-IL-5 receptor), dupilumab (anti-IL-4-13 receptor), and tezepelumab (7).

The reality of an inhaled biologic product hitting the market is still far off, however. Tagliaferri emphasizes that the effective development of an inhaled or even oral biologic (particularly a monoclonal antibody [mAb]) still seems a way off; however, he states, “Based on current clinical trials, we are likely to see self-administered inhaled or nebulized mRNA/LNP biological products, particularly for lung-related conditions in the near future.”

Tagliaferri adds that many of the more successful mAb therapies currently on the market may likely continue to transition to a more patient-friendly, self-administered subcutaneous administration format when applicable. He points out, however, that current technologies still seem insufficient to overcome the dose and stability challenges.

1. Skalko-Basnet, N. Biologics: The Role of Delivery Systems in Improved Therapy. 

, 107–114. DOI: 10.2147/BTT.S38387
2. Pfizer. Pfizer Reports Third-Quarter 2007 Results; Reconfirms 2007 and 2008 Revenue and Adjusted Diluted EPS(1) Guidance. Press Release, Oct. 17, 2007.
3. Pfizer. MannKind and Pfizer Announce Collaboration for Certain Exubera Patients to Transition to MannKind’s Inhaled Insulin Therapy. Press Release, Sept. 15, 2008.
4. Cohen, T., Ed. Inhaled Biologics: Where Are We Now? 

, April 13, 2023.
5. US Specialty Formulations. US Specialty Formulations Completes Phase I of Clinical Trials for the Qyndr Vaccine. Press Release, Sept. 7, 2023.
6. Research and Markets. 

Inhalation CDMO Global Market Report 2024

. Market Research Report, April 2024.
7. Transparency Market Research. 

Asthma Biologics Market (Drug Class: Selective Immuno-suppressants, Interleukin Inhibitors, and Others; Distribution Channel: Retail Pharmacies, E-commerce, and Others)–Global Industry Analysis, Size, Share, Growth, Trends, and Forecast, 2023–2031

Feliza Mirasol is the science editor for 

®
Vol. 37, No. 8
September 2024
Pages: 7–9

When referring to this article, please cite it as Mirasol, F. Exploring Innovative Means for Biologics Delivery. 

Articles

Cover Story

Alternative delivery methods for biologics continues to be explored that offer less invasive, less painful administration.

Exploring Innovative Means for Biologics Delivery

Article Submitted: January 30, 2024.
Article Accepted: April 8, 2024.

Single-use biomanufacturing is a rapidly growing industry. In recent years, single-use centrifuges have become viable alternatives to traditional filters, promising 90% reductions in waste materials and improvements in process time and yield. However, these systems often have several fluid paths with different materials, complicating extractable studies. This case study describes how the risk assessment of the first-to-market single-use disc-stack centrifuge was conducted. This study shows how a dramatic modification of the surface-area-to-volume extraction ratio was required for the single-use system and how this was considered during interpretation of the results respecting industry best practice. Furthermore, it’s demonstrated how the detection of volatiles can vary depending on the approach of analysis, surface coatings, and where analytical study design should be considered to mitigate missing volatile extractables.

Single-use systems (SUS) have revolutionized biomanufacturing and often replace traditional stainless-steel equipment. Presterilized SUS are considered “safer, greener, cheaper, and faster” compared to traditional biomanufacturing systems (1) due to the reduction of water, man-hours, and chemicals. However, the waste handling of large SUS is an environmental challenge, and, therefore, there is a growing interest for single-use (SU) centrifugal separators, which could reduce the waste of SU filters by 60–80% (2–4).

SU centrifuges are used to separate host cell materials from target proteins following fermentation. In a SU production line, the only available options for cell separation are filtration and/or tubular centrifuges (5, 6). Advances in biomanufacturing have greatly increased the cell concentration and batch sizes upstream, which have caused challenges for filtering systems downstream. The performance of depth filters is largely dependent on the colloid content flow-through, and, at higher cell concentrations, the separation becomes increasingly difficult and costly as more filters are needed and exchanged more frequently.

In 2020, a first SU disc-stack centrifugal separator (Alfa Laval) (7) was introduced that offered continuous low-shear separation of cell batches 100–1000 L, without manual replacement of filters and with a limited footprint in the laboratory (see Figure 1). Yields up to 98% and <5% additional lysis could be obtained due to the low-shear design and the large surface area (SA) of the disc-stack inside the disposable separator insert (7).

Since 2020, other and larger SU disc-stack separators have reached the market (3,8), which all need validation and testing.

Martin Kellerer Wåhlander is senior specialist–Materials and Coatings at Alfa Laval Technologies. Michael Creese is director of Chemical Analysis at Smithers MDT Limited. Pontus Linderholm is R&D manager at Alfa Laval Technologies.

®
Vol. 37, No. 8
September 2024
Pages: 17–22

When referring to this article, please cite it as Wåhlander, M.K.; Creese, M.; Linderholm, P. Extractables Protocol for Single-Use Disc-Stack Separators. 

Peer-Review Research

This case study describes how the risk assessment of the first-to-market single-use disc-stack centrifuge was conducted. 

Extractables Protocol for Single-Use Disc-Stack Separators

The biologic drug segment has both expanded rapidly and evolved technologically over the past three decades. Many biopharmaceutical drugs have also reached blockbuster status. Some have already lost patent protection, and many more will during the next decade. All will face competition from biosimilars, which are increasingly accepted by doctors and patients. Biobetters—improved versions of the originator biologic offering advantages such as enhanced efficacy and safety, reduced side effects, and more attractive administration options and dosing frequencies—provide an alternative to biosimilars with greater potential for differentiation in the market. Increased understanding of disease pathologies and more advanced capabilities in the design, engineering, and manufacturing of biologics are leading to growth of the biobetters market, which is predicted to expand at a compound annual growth rate of approximately 8% over the next five years (1,2)

Drug developers pursue biobetters to improve the treatment of diseases, overcome the limitations of existing drugs, and better meet the needs of patients, contends Ulrike Herbrand, scientific director, global 

 bioassays with Charles River Laboratories. “Biobetters are novel drugs that represent an improvement on the original drug and have advantages over the original drug,” she says.

Better treatment options are achieved through improved properties. Examples, according to Herbrand, include a longer half-life, higher stability and selectivity, increased specificity, reduced toxicity and immunogenicity, and/or a different route of administration. “All these factors are related to better efficacy, safety, or patient-friendliness,” she remarks.

Those improved properties can be realized by leveraging innovations in production technology, Herbrand says. “Greater understanding of human biology has enabled identification of opportunities to improve the molecular structure of originator molecules. Advances in cell-line engineering, cell culture processes, and process analytical technologies, meanwhile, enable better control of process parameters and thus more precise control of post-translational modifications and other important quality attributes,” she explains. Similarly, advances in formulation science make it possible to improve upon the formulation of the original therapeutic drug.

There is also an important market driver for the development of biobetters. “Unlike biosimilars,” Herbrand states, “biobetters are considered new drugs and therefore benefit from market exclusivity rights, even if they have similarities to existing therapeutics.”

Common chemical modifications include revising the glycosylation profile with the intention of improving the stability, pharmacokinetics, and immunogenicity of the originator biomolecule, according to Herbrand. PEGylation (attachment of polyethylene glycol to proteins) and sialylation (covalent addition of sialic acid to the terminal end of glycoproteins) are also well-known to improve the half-life, reduce immunogenicity, and enhance solubility, she adds.

Another important strategy is to modify the amino acid sequence of the protein. “Such changes can achieve enhanced efficacy and/or reduced side effects as well allow for engineering of the protein structure so it exhibits improved folding properties, which lead to both better stability and function,” Herbrand comments.

If the originator biomolecule is derived from proteins not of human origin, another chemical modification that is often employed is humanization to make the drug substance more like human proteins, according to Herbrand. This change reduces the risk of immune reactions.

Beyond changing the amino acid sequence, more significant structural modifications are often employed in biobetter development to enhance 

performance. One of the most common structural changes, says Herbrand, is optimization of the binding site to improve its interactions with the target receptor and thus overall function.

As an example, Herbrand points to engineering of the complementarity-determining regions (CDRs) of antibodies. “These are the variable regions of an antibody that directly interact with the target antigen. Rational engineering of CDRs can improve binding affinity and specificity, which can lead to better therapeutic outcomes,” she observes. It is also possible to introduce charged amino acids (so-called charged mutations) near the edges of CDRs to enhance solubility and reduce aggregation. The latter can also be reduced/prevented by introducing other mutations to generate aggregation-resistant domain antibodies, Herbrand adds.

Increasingly, computation approaches are used for structure-based optimization during biobetter development. For instance, predictive computational strategies support the assessment of developability risks early in the lead candidate discovery phase, according to Herbrand. Computational modeling also helps identify key residues involved in binding to optimize binding affinity and predict solubility and stability properties and the potential risk of aggregation.

A key goal of drug developers today is to provide medicines that take into consideration the specific needs of the target patient population so they are easy and convenient to use. As a result, a key aspect of biobetter development includes modification of the formulations of originator drugs to allow for greater patient-centricity.

“Changes in a formulation to support another route of administration, such as allowing the switch from intravenous to subcutaneous delivery, can make the patient experience more convenient and lead to healthcare savings,” notes Herbrand. “Higher concentration formulations, for instance, lead to a reduced application volume and thereby allow for administration via auto-injection devices, which is crucial for patients with chronic diseases (e.g., asthma, diabetes, colitis, or arthritis) who are dependent on regular drug administration,” she adds.

Formulation changes also involve using excipients that enhance drug stability, solubility, and bioavailability, Herbrand comments.

Protein engineering, including site-directed mutagenesis, molecular dynamics, PEGylation, sialylation, and bioconjugation, remains a foundational technology for biobetter development, with advances occurring in many of these areas, according to Herbrand. “Application of nanotechnology to drug design and development is a newer addition to the portfolio of engineering capabilities, with examples including formation of drug products as encapsulated or immobilized nanoparticles to improve pharmacokinetics,” she says.

One development area of particular interest to Herbrand is antibody-drug conjugate (ADC) biobetters. ADCs combine the tumor-targeting properties of antibodies and the cytotoxic potency of chemotherapeutics with the goal of delivering destructive compounds specifically to cancer cells while minimizing damage to healthy tissue. On the innovator side, Herbrand notes that manufacturers are currently working to identify new targets and/or payload mechanisms of action (MoAs).

ADC biobetter development, meanwhile, is focused on ADCs that leverage established target/payload MoA combinations but incorporate novel delivery components to achieve a best-in-class profile. “Non-specific and insufficient payload delivery remains a challenge with approved ADCs. Issues include premature payload release, poor tumor penetration, variable drug-to-antibody ratios, and aggregation,” Herbrand explains. Next-generation ADC technology aims to improve these aspects (3).

Grand View Research. Biobetters Market Size, Share & Trends Analysis Report By Drug Class, by Application, by Route of Administration, by Distribution Channel, by Region, and Segment Forecasts, 2023–2030. 

Mordor Intelligence. Biobetters Market Size & Share Analysis–Growth Trends & Forecasts (2024–2029). 

Sasso, J. M.; Tenchov, R.; Bird, R.; Iyer, K.A.; Ralhan, K.; Rodriguez, Y.; and Zhou, Q.A. The Evolving Landscape of Antibody-Drug Conjugates: In Depth Analysis of Recent Research Progress. 

 2023 34 (11), 1951–2000. DOI: 10.1021/acs.bioconjchem.3c00374 

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

®
Vol. 37, No. 8
September 2024
Pages: 10–11

When referring to this article, please cite it as Challener, C.A. Biobetter Development. 

Development

Weighing development costs/resources and performance benefits is essential. 

Biobetter Development

Filtration is widely used during biologics manufacturing to remove process impurities and contaminants (particulates, viruses) and for bioburden control. Successful filtration operations are therefore essential to successful biotherapeutic production. As bioprocesses move toward intensification and therapeutic modalities increase in physical size and biochemical complexity, the role of filtration continues to evolve.

Optimization of filtration steps for throughput and product recovery while achieving acceptable process economics is becoming more challenging. Collaborations between filtration technology suppliers, biopharma manufacturers, and regulators are enabling the development and adoption of new solutions to meet these challenges.

Several filtration technologies to manage

Filtration technologies fall into four main categories, according to Mike Collins, director of research and development science for filtration management at Cytiva. They include prefilters, such as depth filters for initial clarification; membrane filters for sterilizing final product, but also for bioburden reduction during secondary clarification or following viral inactivation (VI); virus filters for removal of adventitious and endogenous viruses; and tangential-flow filters for concentration of process fluids, for diafiltration to exchange buffer solutions, and for removal of impurities.

Depth filtration, tangential-flow filtration (TFF), and sterile filtration are commonly used within all processes across numerous modalities, including recombinant proteins, antibody-based therapies, and viral vectors, notes Chris Nieder, director of viral vector downstream process development at SK pharmteco. “The choice of membrane materials and molecular-weight cutoff (MWCO) varies depending on the application, and vendors play a crucial role in providing a diverse portfolio of solutions. In recent years, vendors have also focused on sterilized TFF technology, enabling closed processing when necessary,” he says.

While mainly used for removal of cells and cellular debris and to reduce turbidity and soluble impurities at cell harvest, depth filters are also employed following low-pH VI for monoclonal antibodies (mAbs) to reduce turbidity and impurities prior to polishing chromatography, Nieder observes. TFF, meanwhile, is used in many applications, such as prior to capture chromatography to reduce volume (and thus load time) for viral vectors and buffer exchange for mAbs, for buffer exchange between capture and polishing chromatography, and for concentration and buffer exchange for final formulation.

Most depth filters are non-woven media layers or silica media reinforced with fibers and formed into a sheet, according to Paul Beckett, senior strategic product manager at MilliporeSigma. “The legacy materials for depth filters are cellulose fibers and diatomaceous earth (DE, organic silica), bound together with a positively charged resin to bind nucleic acid contaminants,” he comments. The positive charge helps remove nucleic acid contaminants. The silica, either as DE or a synthetic equivalent, adsorbs larger molecules and particles. Increasingly, activated carbon is used because of its ability to adsorb smaller molecules, Beckett adds.

Membrane filtration in biologic manufacturing is deployed to clear smaller particles, typically below 0.5 microns in size, and can be used for bioburden control, virus retention, concentration, and buffer exchange, states Elliott Zell, global new product marketing–bioprocessing filtration with Solventum. Flat or pleated sheet membranes are used in sterilizing grade (e.g., 0.2-micron) filters for bioburden control in many unit operations and for assuring the sterility of final drug products during fill/finish, he notes.

Membrane filters for aseptic (sterile) filtration typically comprise surface-modified polyether sulfone (PES) and are designed for high performance, both in terms of capacity and flux, according to Beckett. They can also be combined into multi-layer devices for challenging feeds, 0.1-µm variants for mycoplasma protection around the bioreactor, and single-layer variants for high-speed buffer filtration.

TFF filters are generally composed of regenerated cellulose when used for high-value applications (mAbs, viral vectors) and when organic solvents are employed (PES is not compatible), while PES membranes find use in robust, workhorse applications like plasma processing, Beckett observes. Cassette devices are most common due to their easy scalability and because they can be reused, but he notes self-contained capsule variants exist for clinical manufacture campaigns and when containment is important, such as for lentiviral (LV) vectors and antibody-drug conjugate (ADC) manufacturing.

Beckett also notes that TFF is increasingly used in upstream perfusion-based cell culture to remove spent media and/or product. These TFF filters, though, have designs (hollow fiber) that differ significantly from those used in downstream processing and typically are made of modified PES or polyvinylidene difluoride (PVDF).

Vent filters are an unglamorous and often overlooked category of filters, says Beckett. They are installed on tanks to maintain atmospheric pressure and enable blow-down and integrity-testing operations. Many contain polytetrafluoroethylene (PTFE) membranes and are sterilized using steam. PES filters are used in niche applications when sterilization by irradiation is required.

Hollow-fiber membranes can also be in nanofiltration devices for clearance of endogenous and adventitious viruses, according to Zell. “Due to the small size of viruses (typically <100 nanometers), membrane filtration can be highly effective at removing viruses while allowing the drug substance to pass through,” he says.

Nanofilters, agrees Jean Aucamp, associate director of biologics R&D for Lonza, are ubiquitous in mammalian bioprocesses due to their ability to effectively remove both endogenous and adventitious viruses.

Different modalities pose different filtration challenges

Many challenges must be overcome to achieve successful filtration operations, and those challenges vary depending on the modality, the desired goals, and the specific filtration operation.

Although manufacturing platforms for mAbs are well-established, challenges to filtration have increased significantly in recent years and in various ways. Improvements in upstream cell culture have, according to Collins, resulted in higher production titers of 5–10 g/liter or more compared to 1–2 g/L a decade ago. “This increase in titer generally comes with higher cell densities (up to 40x106/mL in fed batch), higher turbidity, and an increased level of impurities [host-cell proteins (HCP) and host-cell DNA] that must be removed,” he explains.

While Beckett believes large-scale clarification operations involving continuous centrifugation followed by fine depth filtration can handle these acceptably, two-stage depth filters can struggle to obtain high enough capacities to enable facility fit and economic operation. There is consequently a need for higher capacity clarification filters. Functionalized depth filters are also needed to address the increased level of soluble impurities, which if not removed can impact subsequent chromatographic purification steps, Collins notes.

The higher upstream titers for recombinant proteins are also creating challenges for membrane/aseptic filtration when performed earlier in the downstream process using intermediate membrane filters, according to Beckett. Here again the issue is insufficient capacity. “Specialist intermediate filters that have very high capacity for particulate loads are a viable solution here,” he notes.

There are also challenges during final formulation due to the trend toward higher concentration products (200–300 g/L protein) intended for subcutaneous delivery, according to Nieder. The higher concentrations lead to high viscosity and thus high TFF pressures. “Managing these high pressures in a manufacturing setting can be a concern,” he says. Sterile filtration can also be difficult, with the high viscosities requiring lower flow rates, which can lead to extended processing times. “Oversizing sterile filters can compensate, but then holdup volumes lead to product dilution, which creates new issues,” Nieder comments.

Collins points to high product losses due to nonspecific binding, high non-recoverable volumes, and high pre flush requirements as examples.

Finally, Aucamp observes that nanofiltration for virus removal is challenging mainly due to its high cost and the variation in filter performance seen for different products. In addition, low product concentrations are necessary to achieve sufficiently high flux and short process times, which is against the trend for higher concentrations and leads to larger process volumes. The latter may to some extent negate process-intensification and volume-reduction measures introduced upstream.

On a positive note, Beckett points out that existing filtration technology for viral clearance of standard mAbs is extremely effective. “The smallest parvovirus we are expected to remove to >104 log10 reduction value is not that much bigger than a mAb, and we expect very high product yields (with) short process times for this step,” he comments.

In addition to the challenges outlined for traditional mAbs, viral filtration, according to Beckett, also presents difficulties for bispecific antibodies. “These molecule types have a tendency to aggregate, which greatly reduces capacity on virus filters, and they are larger than standard mAbs. Achieving economic capacities therefore becomes an issue with these challenging feeds,” says.

ADCs are unique in the field of biologic drugs due to their highly potent nature and resultant need to protect operators and the environment from exposure to these complex molecules. “Unlike most bioprocesses, the key challenge here is protecting the operator from the toxic product more than protecting the product itself from the environment,” remarks Beckett. “That can be an issue due to the limited availability of high-quality closed devices that provide appropriate containment during manufacture,” he continues.

Most depth filters on the market were designed with clarification of positively charged mAbs in mind, which can greatly impact step recovery for viral vectors, according to Nieder. The silica component and positive charge of many depth filters typically bind LV vectors quite strongly, says Beckett, as they are both large and have a net negative charge.

Adeno-associated viral (AAV) vectors, while smaller than LVs, also are negatively charged, and existing depth filters have shown low product yields due to virus adsorption for both types of vectors, Collins adds. One alternative approach is to use lower-capacity filters made of cellulose or synthetic equivalents.

Lentivirus sterile filtration can oftentimes lead to low filtration capacity and low recovery, according to Nieder. That is because, explains Beckett, of their large size and tendency to aggregate, which prevent their easy passage through sterilizing grade membrane filters (0.22µm or smaller).

The other challenging filtration step for viral vectors, particularly LVs, is virus filtration to remove undesired viral contaminants. Indeed, due to the sizes of viral vectors (AAV is approximately 20 nm and LV is approximately 120 nm), it is not possible to use the virus filters typically employed in mAb processes, according to Collins. “There is consequently a higher risk of adventitious virus getting into the product stream, and therefore, more emphasis must be placed on reducing that risk by using methods such as closed single-use technologies and applying virus filtration to any process fluids entering the process, such as cell culture fluids and buffers,” he says.

Using a completely closed sterile process that would preclude the need for sterile filtration creates its own set of challenges, however. Beckett highlights the need for closed and sterilized equipment for TFF in the right pore size, which may not be readily available. Adjusting the formulation to reduce aggregation may help for some viral vectors. He also notes that other large, fragile entities such as exosomes and lipid nanoparticles face similar challenges.

Plasmid DNA (pDNA) products have similar issues to those of viral vectors for clarification depth filtration given that nucleic acids have a strong negative charge. Yields for pDNA can be quite low, and often formulation changes and/or the use of non-charged media is/are required, says Beckett.

While advances are occurring in the chemistries used for membrane media, many technology developments are related to new ways of applying existing chemistries and new device designs, Beckett remarks. “As such, advances must be seen within the wider context of the bioprocessing industry as a whole, which is itself evolving. Manufacturers are under intense pressure to reduce product costs and increase speed to market, which is impacting all aspects of bioprocessing. Therefore, although novel solutions have been introduced, many recent advances in filtration technology have been evolutionary rather than revolutionary, and some novel approaches, such as flocculation for harvest pretreatment, have been borrowed from adjacent industries,” he concludes.

Single-pass TFF (SPTFF) is an example of a new application for an existing technology. “This new mode of operation (not a new filter type) is becoming more widely adopted for final formulation of high-concentration mAbs. It has been common in academia and is now finally being adopted by industry because, when developed properly, SPTFF results in a steady-state process able to achieve high concentrations (200–300 g/L) and lower system pressures when compared to traditional TFF,” says Nieder.

When considering potential new filtration technologies, it is essential—as is the case for all aspects of bioprocess development and manufacturing—to evaluate their potential impact on the sustainability of biologics production operations. “Any new product/equipment/technology must be designed with sustainability in mind,” Beckett states. It could be a design that requires less water for flushing, needs fewer packaging materials, has a smaller footprint, or eliminates the use of hydrofluorocarbons for high-performance integrity testing.“New solutions that provide more sustainable alternatives while addressing important filtration challenges will have a higher likelihood of experiencing widespread adoption,” he concludes.

Even though most advances in filtration technology are evolutionary in nature, some noteworthy developments have led to improvements for various modalities.

Depth filtration has received significant attention. A basic improvement noted by Beckett has been the move to synthetic media, which provides comparable performance combined with greater efficiencies, particularly surrounding flush volumes and validation requirements, which in turn lead to more attractive process economics.

To address the challenge of higher cell densities, titers, and impurity levels for mAbs, approaches have included flocculation prior to clarification, acoustic wave separation, and tangential flow depth filtration (TFDF), observes Alexei Voloshin, global head of bioprocess science–bioprocessing filtration with Solventum. He adds, though, that these solutions still have complexities when scaling to large process volumes.

Anion exchange (AEX) fiber chromatography is another solution that, according to Voloshin, has proven to be scalable up to large commercial manufacturing. “This approach leverages a Q-chemistry functionalized fiber bed in a single-use capsule for clarification of harvested cell culture fluid and combines the ease of filter-like flowthrough operation and scalability with the separation precision of chromatography,” he explains.

Functionalized fiber technology can, in fact, perform chromatographic separations across the entire range of process impurities, from whole cells to cell-culture media components, Voloshin contends. Commercial solutions, he adds, enable step changes in the speed of process design, scale-up, and improvements in process economics. “Solventum (formerly 3M Health Care), for instance, offers a functionalized fiber clarification platform designed to accelerate development of mAb candidates expressed in modern, intensified, Chinese hamster ovary cell cultures from discovery to commercial manufacturing,” he says.

TFDF is also becoming more widely adopted for clarification of LV vectors, notes Nieder. “By combining TFF with a membrane having depth like a depth filter, TFDF has led to high recovery and capacity when compared to traditional depth filters,” he observes.

For the larger moieties in the cell and gene therapy space, new separation technologies based on novel ideas are also being explored, according to Voloshin. He highlights functionalized fiber beds and polymer-coated beads offering filter-like flowthrough functionality while trapping process-related contaminants by size, charge, or other characteristics. “In these cases, the line between conventional ideas of filtration and chromatography is blurred to take advantage of both the size and the biochemistry of the drug substance modality,” he notes. “As this field evolves, we’re likely to see much more advanced filter-like process technologies employing advanced physics and chemistries at the core of the separation mechanisms,” Voloshin believes.

In the area of aseptic filtration, basic improvements to device designs are enabling in-situ integrity testing within fill/finish isolators and strengthening of vents on capsules, according to Beckett. More advanced developments involve improved membranes that allow for higher capacity, lower protein binding, and the ability to reduce footprints.

One example of the latter is a new sterile filter technology from Cytiva that address the challenges associated with high-concentration biologic feeds by solving the issue of premature filter blockage from high particle loads. “This new sterile filter can deliver high throughput capacity without the need for oversizing, thus avoiding problems associated with increased hold-up volumes and costly product losses,” Collins says.

Another issue being considered in this area is whether validated, sterilizing-grade filters are needed for intermediate filtrations performed for bioburden/particulate control between unit operations, and usually to protect chromatography columns from fouling and filtration of non-critical buffers in early downstream operations. “Given a substantial part of the filter cost is the testing, validation, and documentation to demonstrate the sterilizing grade, a more open membrane or one with less documentation would likely be both cheaper and have significantly higher capacity for the challenging feeds seen early in biopurification processes,” Beckett states.

Finally, Beckett notes that the recent publication of the long-awaited EudraLex Volume 4 Annex I update on the manufacture of sterile products has laid out regulatory expectations very clearly for membrane filtration. “Certain expectations, particularly those regarding pre-use post-sterilization integrity testing (PUPSIT), have driven innovations and technology advances in membrane filtration to ensure regulatory compliance now and for the future,” he says.

According to Beckett, advances in TFF technology include the open ultrafiltration range of membranes (300–1000 kDa nominal MWCO), for which pore-size control issues during membrane manufacture have been overcome, affording more robust separation solutions; innovations in channel screen technology that allow for processing of high-concentration products; and closed sterilized devices that reduce validation overhead for ad hoc clinical campaigns and allow closed processes for product and/or operator safety.

For viral filtration, advancements have focused on further improving the high capacity and robustness of existing membranes to support dirtier feeds and more challenging products such as bispecific antibodies, Beckett says. He adds that as for other filtration applications, with intensified, integrated, and closed processing becoming a greater need, closed designs that can be irradiated are also in development across the industry.

As the role of filtration is central to bioprocess design and touches many parts of the process, the next generation of filtration and filter-like solutions will undoubtedly be designed by a collaboration of technology providers, biopharmaceutical manufacturers, and regulators, Voloshin observes. Indeed, advances in filtration for bioprocessing do not occur in a vacuum. Drug manufacturers and regulators provide the requirements for new technologies. Manufacturers also play a big role in developing new approaches to using existing technology.

Technology suppliers, and in some cases academic labs, are largely responsible for development of new solutions. “It is critical for all groups to work collaboratively to progress new technologies effectively,” Collins states.

Manufacturers, adds Beckett, perform the critical role of informing suppliers about their greatest pain points, where the bottlenecks with processing exist, and how a product would need to perform to overcome barriers to entry associated with change control in a regulated process.

“Collaboration with vendors is a great way to assist in getting new products to market,” Nieder agrees. Vendor collaboration can also present opportunities to evaluate products in early-stage development and provide feedback to improve design and performance, he observes.

The basic idea of filtration has come a significantly long way as the biotechnology industry has evolved. As bioprocess design moves forward, Zell expects to see much more inventive and exciting approaches to filter-like separation technologies.

“The basic premise of completely flow-through biopharmaceutical processes is on the horizon, and it is the advanced filtration solutions of the future that will enable safer, more efficacious, and more accessible biopharmaceutical drugs around the world,” Zell avers.

Beckett adds that there is a paradigm shift underway regarding the manufacturing of biopharmaceuticals. Changes include new pressures on the cost of goods, a shortage of blockbuster drugs that require 60,000-L bioreactor capacity, and new classes of biopharmaceuticals such as ADCs and viral gene therapies that are much more potent than existing classes and therefore require less volume.

“Filtration technology must fit into what the bioprocess facility will look like in 2040, not now. That facility is likely to be much smaller, entirely single-use, multi-product ballroom production and designed for agile manufacture of multiple product types in a single line. To support such facilities, filtration technology must be smaller, cheaper, and/or faster, which are the three basic elements of bioprocess intensification,” Beckett concludes.

Cynthia A. Challener, PhD, is contributing editor to 

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Vol. 37, No. 8
September 2024
Pages: 12–16

When referring to this article, please cite it as Challener, C.A. Advances in Filtration Technology. 

Downstream Processing

Collaboration between technology providers and biopharma manufacturers are enabling both evolutionary and novel developments.

Advances in Filtration Technology

Successful biomanufacturing processes not only provide the desired product in high yield and purity, they provide consistent results whether implemented in the lab or the production plant. For many monoclonal antibody (mAb) products, processes must consistently perform at scales ranging from hundreds of milliliters to thousands of liters. Lack of scalability can result in significant project delays and added cost due to the need for further optimization. Developing scalable processes from the outset is therefore the most effective approach to ensuring the smooth advancement of mAb projects through development to commercialization.

The main technical challenges faced during the scaling of upstream mAb processes include variations in cell densities, cell viabilities, and product concentration, as well as potential offsets in product quality attributes, according to a spokesperson from Boehringer Ingelheim. These attributes can be impacted by the bioreactor design, process parameters such as temperature and oxygen transfer, media composition, supplement and feed strategies, and numerous other factors. Obtaining process understanding is therefore essential to establishing robust, scalable processes.

“Addressing these scale-up considerations in upstream mAb process development ultimately comes down to the timeline, budget, and priority of the developer,” says Leslie Wolfe, site head and vice-president (VP) of process development at KBI Biopharma. She notes that it is imperative to fully understand what knowledge exists and what is needed as part of the scope to help support effective process design. Because time and cost are often the most important drivers during early phase development, there may be a necessary trade-off in the form of reduced process knowledge and understanding of the design space. “One potential consequence,” observes Lorenz Hasler, VP of global manufacturing, science, and technology at KBI Biopharma, “may be reduced knowledge of key inputs to process design regarding quality attributes and process performance and underestimation of considerations as they relate to commercial manufacturing equipment.”

Benefits of established platform processes

An important consideration for mammalian upstream processes for mAb production, notes Hasler, is that the potentially critical respective key scale-up factors are comparable between processes. “Process knowledge and expertise can therefore be leveraged between processes. Because potential key parameters and equipment limitations can be taken into consideration upfront, potential scale-up issues can be reduced,” he explains. Risk analysis tools, Hasler adds, can then be used to screen and understand other potential process variables specific to the mAb candidate and thereby mitigate potential process risk at scale.

The best approach to ensuring scalability of mAb production is to use a platform process rather than focusing on individual project variations, observes the spokesperson from Boehringer Ingelheim. Taking this approach, it is possible to manage challenges to scalability using standard equipment (bioreactors).

Wolfe agrees that working with an established and scalable platform is key to mitigating the risks associated with scaling up. She notes that such a platform is typically developed through iterative application, which helps in establishing critical process knowledge.

“This knowledge and understanding form the foundation for establishing a process control and monitoring strategy tailored to each unit operation, leading to a potentially robust and reliable scale-up approach,” says Hasler. Platform processes may also speed up development activities because process development, and facility-fit assessments can leverage process knowledge and understanding, he adds. These platforms also help balance the timeline-versus-process-knowledge conundrum for programs with aggressive development timelines.

Relying on platform processes to ensure scalability must be pursued with some caution, however. “Conditions and predictions to perform a process at scale or commercial process for any new drug substance or drug product still need to be demonstrated at laboratory or pilot scale,” Hasler states. Additional information may also be needed to support the requirements of specific mAb-based candidates. When necessary, for instance, Boehringer Ingelheim uses computational fluid dynamics and process modeling, including detailed equipment characterization, to ensure smooth scale-up.

To ensure scalability for upstream mAb processes, designing an efficient process complemented with an effective process control approach is critical and should be tackled during early process development, according to Hasler.

For Boehringer Ingelheim, a critical aspect of its scalability approach for mAb processes is the selection of a robust clone during early development. The chosen clone, says the company’s spokesperson, should not only fit the platform, but also exhibit robustness in relation to classical scaling parameters.

Even when a platform process is employed, Hasler recommends generating process knowledge for a specific mAb candidate using design-of-experiment studies, which help in defining the relationships and multivariate interactions between various process parameters and resulting outputs. He notes that it is also crucial to develop compelling analytical methods to support these small-scale studies. Demonstrating scalability of upstream mAb processes at an intermediate scale is beneficial as well, according to Wolfe, as doing so helps to de-risk scale-up to manufacturing.

Finally, Hasler comments that for mAbs with expedited approval designations, the shortened development timelines may lead to a reduced approach to process design and, therefore, reduced process knowledge and understanding. To balance the potentially reduced process development activities, he suggests that a detailed gap identification and subsequent risk evaluation may support potential scale-up considerations and success.

Consistent scale-up through platform approach

Platform processes not only streamline the development of scalable processes, they also make it possible to use a consistent approach to scale-up across all mAb-related projects. That is the case at Boehringer Ingelheim. “We do not test different scale-up strategies for our projects, as our scale-up strategy is not influenced by the specific product being expressed. Whether the product is a standard IgG1 [immunoglobulin G1] antibody or a trispecific molecule, the scale-up strategy generally remains the same,” says the spokesperson from Boehringer Ingelheim.

While general scale-up strategies also apply to more complex or advanced antibody-based therapeutics, Wolfe observes that appropriate risk assessments should be conducted and considered with more complex therapeutic targets to ensure sufficient knowledge is available. “Using this approach ensures the target product quality profile is achieved from the defined process,” she concludes.

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Vol. 37, No. 8
September 2024
Pages: 27–28

When referring to this article, please cite it as Challener, C.A. Considering Process Scaling for Monoclonal Antibodies During Early Phase Development. 

Manufacturing

Platform processes and effective risk assessments help overcome time and cost challenges.

Considering Process Scaling for Monoclonal Antibodies During Early Phase Development

Adventitious agent testing remains critical in biomanufacturing to help ensure product purity. As such, testing protocols from monoclonal antibody (mAb) manufacturing may be transferred to gene therapy manufacturing, as the optimization of testing practices are applicable to gene therapy manufacture.

For instance, in conducting tests to confirm a biological product’s safety, it is necessary to use multiple assays to ensure that various contaminants are identified. Several assays are commonly used in combination to test for adventitious agents, which is required by regulatory bodies, including FDA and the European Medicines Agency. The two main types of assays for identifying adventitious agents are 

 assays are utilized when mammalian cell lines are used to produce biopharmaceuticals, while 

 tests to detect viruses that are not able to be grown in cell culture (1).

Of more immediate concern is the fact that more complex modalities of biopharmaceuticals are prevalent in the industry pipeline. These complex modalities typically require more complex manufacturing processes, which means each product in development is a more significant investment of time and energy as well as patient trust. The current climate makes thorough biosafety testing procedures more crucial for biopharma developers (2).

Adventitious agents comprise a broad range of contaminants, which are unintentionally introduced into the biomanufacturing process. These agents include bacteria, fungi, viruses, mycoplasma, parasites, and mycobacteria, among others. A common way that adventitious agents enter the biomanufacturing process is via starting materials that are animal or human origin. These materials include cell substrates, bovine serum, or the cell lines themselves, or may be introduced by the manufacturing operators, such as where manual handling or processes are concerned (2).

Inadequately tested biopharma products that end up with contamination run the risk of investigation, corrective action, and downtime in manufacturing that ultimately costs the manufacturer—and developer—millions of dollars or more. Therefore, having preventative strategies and comprehensive testing in place is imperative in biologics manufacturing. Another issue to consider is that contamination can happen at any point in the process between securing the cell bank to the fill/finish stages. To mitigate contamination risk and ensure efficient workflow, it is necessary to test for adventitious agents at multiple timepoints. It is also worth it to note that testing and detecting any contamination earlier in the manufacturing workflow, rather than just relying on testing prior to final product release, can better ensure that tainted product does not reach the market and can save time, cost, and effort (2).

For virus detection, methods include traditional culture-based methods as well as electron microscopy studies, 

 molecular and antibody assays, sequencing methods such as massive parallel or next-generation sequencing, and degenerate polymerase chain reaction (PCR). Methods for detecting bacteria also include culture-based approaches and PCR but can also employ biosensor-based methods. Meanwhile, for other adventitious agents such as mycoplasma, detection can include PCR—this includes specific PCR kits, microbiological culture methods, and enzyme-linked immunosorbent assays (3).

Similarly, the adventitious agent testing requirements for viral vectors are consistent with the requirements for other modalities of biotherapeutic products, including selection of appropriate testing methods. However, a direct transfer of testing strategies used in recombinant proteins and mAbs may not necessarily be feasible or practical for viral vectors. Biological differences between viral vectors and large-molecule proteins hinder direct adoption of testing strategies (4).

Because viral vectors are themselves viruses, standard assays may need to be modified or alternative methods used for testing them. That factor can interfere with virus detection methods during adventitious agent testing. Other complications arise if cell-based assays are used to test live-virus vaccines, replication-competent gene therapy vectors, or vectors that exhibit the cytopathic effect. The issue stems from the fact that human cell lines are primarily used to develop cell-based assays, which are susceptible to human viruses. Adenoviral products, which are lytic viruses, will, for example, infect both human and primate-derived cell lines, which would invalidate the assay. On top of that, there is always the risk that cellular toxicity may occur (4).

If adventitious agents are detected, an important step is to identify the species and the origin(s) of the contamination. It is then important to evaluate the agents’ potential to infect humans (5). Some adventitious agents still find their way into the end product despite extensive detection efforts. Examples of these occurrences include the presence of porcine circovirus 1 found in a commercial rotavirus vaccine and a novel rhabdovirus in a 

 adventitious agent testing methods are usually sufficient, but they have their limitations. For one thing, test sensitivity may not be high enough to detect certain contaminants or too-low concentrations of contaminants. Some assays require lengthy times to perform. What’s more, different testing methods inherently have different sensitivities for detecting different contaminants, and each method has its own limitations. Fortunately, these different methods can complement each other and, when combined, can offer greater understanding of detecting adventitious agents (4).

The delivery times for some adventitious virus test results can be challenging, regardless of which testing methods are used. Some assays may take several weeks to generate results. On top of that, certain biotherapeutics, such as gene therapies, have short shelf lives, so waiting on results for adventitious agent testing may come too late. This is a concern for autologous cell therapies that are dependent on gene-modified components and must be administered to the patient soon after they are produced (4).

On the positive side, detection technologies for adventitious agent testing continue to evolve, with a focus on higher sensitivity, rapid methods, and broad detection ranges. The downside is that new technologies take time to develop, and they must be thoroughly validated to demonstrate their suitability and applicability before the bio/pharma industry and regulatory bodies will accept them for implementation into the testing strategies for adventitious agent control in biomanufacturing (9).

 (accessed July 10, 2024).
2. Thermo Fisher Scientific. Improving Adventitious Agent Testing in Biologics Manufacturing. 

, Feb. 9, 2023 (accessed July 10, 2024).
3. Morris, C.; Lee, Y. S.; Yoon, S. Adventitious Agent Detection Methods in Bio-Pharmaceutical Applications with a Focus on Viruses, Bacteria, and Mycoplasma. 

, 105–114. DOI: 10.1016/j.copbio.2021.06.027
4. Challener, C. Adventitious Agent Testing for Viral Vectors. 

 (9), 40-44.
5. Klug, B.; Robertson, J. S.; Condit, R. C.; et al. Adventitious Agents and Live Viral Vectored Vaccines: Considerations for Archiving Samples of Biological Materials for Retrospective Analysis. 

 (51), 6617–6625. DOI: 10.1016/j.vaccine.2016.02.015
6. Victoria, J.G.; Wang, C.; Jones, M. S.; et al. Viral Nucleic Acids in Live-Attenuated Vaccines: Detection of Minority Variants and an Adventitious Virus. 

 (12), 6033–6040. DOI: 10.1128/JVI.02690-09
7. Dubin, G.; Toussaint, J. F.; Cassart, J. P.; et al. Investigation of a Regulatory Agency Enquiry into Potential Porcine Circovirus Type 1 Contamination of the Human Rotavirus Vaccine, Rotarix: Approach and Outcome. 

 (11), 2398–2408. DOI: 10.4161/hv.25973
8. Ma, H.; Galvin, T. A.; Glasner, D. R.; Shaheduzzaman, S.; Khan, A. S. Identification of a Novel Rhabdovirus in Spodoptera frugiperda Cell Lines. 

 (12), 6576–6585. DOI: 10.1128/JVI.00780-14
9. Playter, G. Examining Next-Gen Technology for Adventitious Agent Testing. 

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Vol. 37, No. 8
September 2024
Pages: 29–30

When referring to this article, please cite it as Mirasol, F. Meeting Adventitious Agent Testing Needs for Complex Modalities. 

Analytics

Viral vectors and other complex biologic modalities require more specificity and higher sensitivity to detect and distinguish contaminants.

Meeting Adventitious Agent Testing Needs for Complex Modalities

It is well-known that developing a drug from the discovery through to commercialization is a costly endeavor, with market analysis showing that the average R&D cost to develop an asset for 2022–2023 was $2.3 billion (1). However, many drugs do not make it through to commercialization, in fact it has been reported that clinical attrition rates for drugs that have reached Phase I trials is as high as 90% of drug candidates (2).

As a result of the high costs and level of risk inherent with drug development, it is imperative that companies efficiently determine the safety and efficacy of their candidates, to minimize any potential failure. “Bioanalytical testing is essential in drug development because it ensures the safety, efficacy, and quality of pharmaceutical compounds through quantitative analysis of drugs and their metabolites in various biological matrices such as plasma, urine, blood tissue, [and so on],” asserts Sujata (Suzzy) Bhavekar, study director at SGS North America. “Early identification of side effects through rigorous testing can reduce development costs by up to 20% (3). Drugs with robust bioanalytical data are 50% more likely to gain regulatory approval (4).”

“Bioanalytical testing covers a range of techniques and technologies used to quantify drugs and their metabolites, or biomarkers, in biological media,” adds Iain Love, director, Chromatographic Bioanalysis & Discovery Sciences, Department of Chromatographic Bioanalysis, Charles River. “The concentration data generated through bioanalytical testing are important as they inform researchers on how long a drug stays in the body and the beneficial effects or otherwise while it’s in there. Knowing the concentration of drug candidates and understanding the levels at which the drug has positive or negative effects on the body is critical to drug development.”

Vital data on drug absorption, distribution, metabolism, and excretion can be gained through bioanalytical studies, which helps developers to determine dosing regimens, agrees Bhavekar. “Poor pharmacokinetics contribute to 30% of drug failures, highlighting the importance of accurate testing (5),” she says.

Additionally, bioanalytical studies help with biomarker discovery, which improves the success rate of targeted therapies by 25% and supports personalized medicines (6), Bhavekar continues. Furthermore, suitable bioanalytical testing helps ensure compliance with regulatory standards, including good laboratory practice (GLP) and good clinical practice (GCP). “Approximately 85% of drug applications meet approval criteria with solid bioanalytical data (7),” Bhavekar says.

“Regulatory considerations are extremely vital in bioanalytical studies to ensure compliance with international standards and facilitate successful drug approval,” continues Bhavekar. “Adhering to GLPs and GCPs is essential to ensure data accuracy, reliability, and reproducibility.”

“Bioanalytical testing is carried out according to strict inter(national) guidelines and quality management systems,” agrees Love. “Monitoring authorities translate globally recognized quality management systems into national regulations.”

At the national level, there are guidelines such as FDA’s guidance documents on bioanalytical method validation and immunogenicity (7,8) and the European Medicines Agency’s guidance on bioanalytical method validation (9), Bhakevar adds. “Compliance with 21 CFR [Code of Federal Regulations] Part 11 (10) is crucial for maintaining the credibility of electronic records and ensuring data integrity,” she says.

“In addition to these national regulations, bioanalytical studies are also carried out following the International Council for Harmonisation (ICH) M10 guideline,” confirms Love. In fact, EMA’s guidance on bioanalytical testing has been superseded by the ICH guidance (11), since its publication in 2022.

“The ICH M10 guideline provides a harmonized approach across various regions including the US [United States], EU [European Union], Japan, and other member countries [and] provides a robust framework for validating methods, focusing on precision, accuracy, selectivity, sensitivity, and reproducibility, thus enhancing global consistency in bioanalytical testing,” Bhakevar specifies. “These regulatory frameworks, including ICH M10 and FDA guidelines, form the backbone of robust bioanalytical testing, driving drug development toward clinical and commercial success.”

“Outsourcing partners are an increasingly important piece of the drug development puzzle,” notes Love. “Partnership with a bioanalytical provider can bring about several tangible advantages that can help get drugs to the patients who need them in the shortest time possible. This could be from simple access to appropriate analytical platforms to receiving advice on planning the development program.”

In terms of regulatory compliance, the right partnership with a contract research organization that complies with global regulatory standards can ensure that the bioanalytical data generated meets the relevant requirements, Bhakavar explains. “Comprehensive services [provided by a partner company], including method development, validation, and routine analysis, allow sponsor companies to focus on core R&D activities while relying on their outsourcing partner for specialized testing,” she says.

“Outsourcing partners are also likely to be able to apply experience gathered from across a broad portfolio of modalities and development scenarios that can inform program decision-making,” confirms Love. “More than ever, bioanalytical science is involved in shaping programs, so careful selection of an expert outsourcing partner is an activity that can bring about the significant benefits involved with an accelerated drug development program.”

There are also benefits in terms of the flexibility and scalability of operations that a partner company can provide for a sponsor’s needs, Bhavekar remarks. “Outsourcing provides flexibility in scaling bioanalytical operations according to project needs, from preclinical to late-stage clinical trials. This scalability helps manage resources efficiently and reduces the burden on in-house teams,” she says. “[Additionally], with large-scale facilities and automated processes, outsourcing partners can handle high volumes of samples, ensuring rapid data delivery and accelerating the drug development timeline.”

As the field of bioanalytical testing evolves, it is important for drug developers to stay at the forefront of the advancements to ensure they remain competitive.

BioPharm International, September 2024

Exploring Innovative Means for Biologics Delivery

Extractables Protocol for Single-Use Disc-Stack Separators

Biobetter Development

Advances in Filtration Technology

Considering Process Scaling for Monoclonal Antibodies During Early Phase Development

Meeting Adventitious Agent Testing Needs for Complex Modalities

Leveraging Bioanalytical Studies Advancements

Responding to Mpox

Keeping Audit and Inspection Programs Current