Photo Credit: Maria Toutoudaki/Getty ImagesPlastic is a relatively new material for parenteral containers. 

 spoke with Graham Reynolds, vice-president of marketing and innovation of Pharmaceutical Delivery Systems at West Pharmaceutical Services and Gary Waller, North American vice-president of sales and marketing for SCHOTT Pharmaceutical Systems, to gain insight on the drivers for and concerns with use of plastic in vials and syringes. 

 Do you see a trend toward using plastic instead of glass in parenteral containers, such as syringes and vials?  			

 There has been a trend toward the use of plastic for primary containment for pharmaceuticals and biopharmaceuticals for many years. The primary market change has been in Japan, where estimates suggest that 60–70% of all prefilled syringes in the Japanese market are plastic, rather than glass. The trend has been driven by increasing demand for higher quality products that will reduce breakage and increase functionality.  

Issues with glass breakage and delamination are also causing concern in the marketplace. Glass can break at any time: in production, when used within a device such as an auto-injector, or even when in use by the patient or caregiver. Breakage in production or in the final product may cause loss of sterility of the drug product and hazards to patients and caregivers. With the increasing use of devices as part of a combination product, a glass container may not be visible, resulting in concerns about breakage when a device is dropped and a tendency to err on the side of caution. For example, patient instructions may suggest an auto-injector should be discarded if dropped, due to the risk of glass breakage. 

Although Japan has led the way in adopting plastic as a primary container, there has been increased interest from Europe and the United States in use of plastic instead of glass. Recent surveys have placed interest in plastic at different levels, but it is West's understanding that the majority of pharmaceutical and biopharmaceutical companies are at least considering plastic as an alternative to glass. 

 In fact, both materials have advantages as well as disadvantages. Polymer or plastic resists breakage extremely well and is also inert and resistant to broad range of polar solvents, acids, and bases. Polymer can also be used to produce flexible designs and dimensions that are often more difficult to manufacture with glass. Japan has historically been using polymer syringes, due to safety and breakage issues. But it's not really a global phenomenon. 

What are the main drivers for using plastic instead of glass? 

 The drivers behind the use of plastic vials and syringes instead of glass are very different. In the case of glass vials, the interest in plastic has been led by breakage concerns as well as various product recalls relating to glass particles. Under certain conditions, glass particles (i.e., lamella) are formed by delamination on the surface of the glass vial. In the past several years, FDA has initiated a number of recalls due to the risk that glass particulate may enter a patient through drug products, particularly those that are administered intravenously. A study conducted by West indicated that clinicians have concerns about the potential harmful effects of glass particles when injected into the body, especially directly into the bloodstream. Plastic vials offer an alternative because the nature of the material eliminates delamination and reduces the potential for breakage. 

For prefillable syringes, the main drivers toward plastic have centered not only on glass breakage but also on the functionality of the syringes, which must be siliconized when made of glass. It has been shown that when used in conjunction with certain biologic products, particularly proteins, silicone oil can cause problems such as the formation of protein/silicone aggregates, which may alter the integrity of the drug product. Another issue is that in the formation of a glass syringe, a tungsten pin is used to create a hole. The needle is then bonded to the syringe using an adhesive. Residual tungsten has been shown to cause stability problems with certain biologics. Use of plastic syringes provides an alternative that eliminates the needs for silicone oil, tungsten, and adhesives. 

In addition, prefillable syringe systems are often used in conjunction with a device, such as a self-injection system or needle-safety system. The inherent variability in the dimensions of glass can lead to challenges when designing a device because many devices put stress on glass products, particularly in the flange area, where breakage can occur. 

There are many drugs that, by their very nature, simply do not work as intended when contained in glass. For those applications—whether it is delamination or interaction with particularly aggressive materials—plastic may be the only option.  

In addition, one of the many benefits of plastic is that it offers significant design flexibility and increased dimensional precision. When developing more sophisticated devices such as pump systems and patch injectors, the use of a plastic container may offer significant advantages by providing a consistent functionality for the system. For example, an electronic patch injector platform technology (SmartDose, West) uses a polymeric (Crystal Zenith, Daikyo) cartridge that is designed to offer a high degree of dimensional tolerance and functional consistency, which enables the device to function effectively. As another example, a 1 mL-long plastic (Crystal Zenith, Daikyo) syringe has the potential to be filled with a volume in excess of 1 mL and maintain an effective seal.  

Plastic is used to produce various types of parenteral containers. We continue to experience an increase in discussion around syringes. In other areas such as cartridges, vials, and ampoules, plastic use is a niche. The general advantages of plastic are naturally drivers for using this type of container material. We do not, however, see a trend to switch from established glass containers to plastic containers due to one specific advantage. We have the ability to evaluate the complete package and consider all influencing variables. If glass delamination is a concern, specialized analytical services (SCHOTT Pharma Services) can determine a suitable solution, possibly by using delamination-resistant, coated vials (Type I plus, SCHOTT).  

Many pharma companies are looking at the syringe side when speaking about plastic containers. Polymeric, prefillable syringes (TopPac, SCHOTT) are transparent like glass and offered with an integrated luer lock, which makes this system even more robust than a glass syringe, in which the luer lock adapter is attached as a separate component. This solution is ideal for highly viscous drugs, such as hyluronic acid. Flexible design and tight dimensional tolerances make these syringes compatible with various intravenous connectors, thus ensuring patient safety.   

What are the primary concerns with using plastic?  

 Concerns are scratch sensitivity, inferior barrier against oxygen and water vapor, and limited long-term experience. A polymer could be scratch-sensitive if it is not handled more delicately than glass. It is important to keep in mind that scratches are not only a cosmetic defect but can also impair camera inspection. Furthermore, polymers do have challenges in the area of barrier protection against oxygen and water-vapor permeation, and this could pose a problem for certain drugs. Glass has been around much longer, and leading companies have a wealth of knowledge on how it interacts with certain medications. So it really boils down to understanding and selecting the material that suits a specific application most effectively. 

 Glass is a traditional packaging material in the pharmaceutical industry. It has been used for many years, and any novel material presents a potentially risky change in a market that is extremely risk-adverse. However, there are more than 20 products that have been approved and are currently on the market in systems using cyclic olefin polymer (Daikyo Crystal Zenith, developed by Daikyo Seiko and sold by West and Daikyo Seiko). Many other products are available in a variety of plastic materials from other manufacturers. Plastic is not a new material for drug packaging, but for many applications, such as biologics, there is still a concern about the number of products that are approved in plastic. 

In addition, there are features of plastic that are different than glass. As an example, oxygen permeability of polymers is typically inferior to glass, and manufacturers must evaluate packaging options on a drug-by-drug basis to ensure that if a product is oxygen-sensitive, proper care is used to select appropriate packaging systems. 

In all cases, it is important to understand the needs of the integrated drug-delivery system and evaluate appropriate solutions. When working with a company on high-value or sophisticated biologic products, we may recommend a polymer as an alternative to be evaluated alongside glass. Given what we know about the limitations of glass, it is important to evaluate alternatives based on the drug product, including in what format it will be used (e.g., vial or syringe and whether the primary container will be used within a device). We would make a recommendation to our customers based on the most appropriate packaging solution for their product.

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Features

A Q&A with SCHOTT Pharmaceutical Systems and West Pharmaceutical Services

Using Plastic for Parenteral Containers

Concerns about unsafe products from large pharmacy compounders, continued emergence of counterfeit medicines, and the prospect of diverse state tracking requirements for prescription drugs are spurring action on Capitol Hill. House and Senate leaders are crafting legislation to address these issues, but divergent Republican and Democrat approaches for revising FDA authority threaten to stymie timely legislative action.  

Meanwhile, reports keep piling up about adulterated and unauthorized drugs. FDA recently uncovered Internet sales of a foreign version of Allergan's cosmetic treatment Botox (onbotulinumtoxinA), a sterile product, and Teva Pharmaceuticals has reported fraudulent versions of its generic Prilosec (omeprazole). Pfizer is challenging widespread Viagra (sildenafil) counterfeiting by marketing its product directly to consumers through its own website, with CVS Caremark filling the orders.  

Reports of more than 50 deaths and widespread serious medical problems from fungal meningitis linked to contaminated products from a large compounder makes action most likely on legislation to curb large-scale compounding of high-risk drugs. Public outrage over the failure of state and federal agents to detect and prevent the outbreak has generated support for proposals to enhance FDA authority over compounding. Granting FDA more authority, however, will require House Republicans to shift from blasting FDA for inaction and tackle the regulatory challenges directly.  

At an April 2013 hearing before the House Energy and Commerce Committee (E&C), Republicans criticized FDA commissioner Margaret Hamburg for not cracking down on the New England Compounding Center (NECC) in Massachusetts, despite NECC's long history of failed inspections and contamination problems. Democrats echoed these concerns but supported legislation that would clarify and strengthen FDA's ability to inspect and bring action against compounders, which now fall primarily under state pharmacy regulation. Hamburg noted that some compounders denied FDA inspectors access to facilities and records during a recent FDA inspection campaign, forcing the agency to seek court warrants.  			

FDA supports legislation that distinguishes local, traditional pharmacy compounders that prepare drugs to treat specific patients with specialized needs in response to individual prescriptions, from large compounders that produce drugs in advance of any patient-specific prescription and market drugs across state lines. States would continue to oversee traditional compounders and license compounding pharmacists, but large operators would be considered a new class of drug manufacturer and have to comply with GMPs, submit to regular FDA inspections, and report adverse events related to their products. These firms also would pay registration fees to FDA to support federal oversight and clearly label products as compounded drugs. Unlike pharmaceutical manufacturers, though, they would not need approved new drug applications (NDAs) for products they compound. FDA would develop a list of products banned from all compounding, such as complex dosage forms and most biologics.  

Some of the challenges in reaching agreement among compounders, pharmacists, and state regulators were discussed at a hearing held on May 9 by the Senate Health, Education, Labor & Pensions Committee. A Senate bill that essentially supports FDA's approach for distinguishing between "traditional" compounders and "compounding manufacturers" received generally strong support. But there were questions about whether a hospital pharmacy that sends compounded products to a satellite facility in another state would fall under FDA's purview, and whether FDA should have access to records of traditional compounders to ensure that no illegal activity is taking place. 

FDA has pressed for legislation to clarify its authority to regulate pharmacy compounders, which has been mired in legal debate for some 20 years, with FDA largely on the losing end. After the Supreme Court tossed out an FDA compounding regulation in 2002, the agency essentially gave up and directed its resources to other pressing issues. When signs of malfeasance at NECC appeared, "we allowed ourselves to be far too cautious due to fear of litigation that would further undermine our authority," Hamburg told the E&C panel.  

FDA recently conducted dozens of inspections of large-scale firms making sterile products and has issued FDA-483 inspection reports that reveal an array of contamination and quality failures. The agency has instigated numerous product recalls, and some of the worst offenders, such as NECC, have shut down.  

Some Republicans claim that FDA has sufficient power to inspect and bring charges against clearly violative compounders, and that new legislation won't help an agency that fails to protect the public health when it should do so. FDA also is wary that cracking down harder on compounders could aggravate shortages of sterile products. Moves by FDA and states to shut down large compounders could disrupt the supply of necessary drugs to hospitals and providers, Hamburg acknowledged, emphasizing the need for "tailored authorities" appropriate for compounders.  

There's even more political disagreement over legislation to better secure the nation's drug supply chain by establishing a system to track pharmaceuticals from production to patient. Several senators sought to have a track-and-trace bill included in the FDA Safety and Innovation Act (FDASIA) last year, but agreed to pull it to avoid delay on the broader FDA measure. A comprehensive tracking policy in California that goes into effect in 2015, however, is spurring efforts to establish a national drug-tracking system that would supersede diverse state requirements—a key goal for manufacturers that benefit from a uniform national distribution process for medical products.  

Bills crafted by House and Senate leaders generally agree on lot-level tracking, plus national standards and licensing for wholesale distributors. Both bills pre-empt state pedigree laws, with the Senate measure giving states more leeway to enact more stringent requirements.   

The main point of dispute is the approach to product serialization and tracking. FDA seeks tracking to the drug unit level, with an interoperable electronic data system able to support efficient recalls and quick identification of illegal and substandard products. While most manufacturers now accept that approach, they side with distributors and pharmacists that want to start with lot-level product serialization and tracking as a more affordable and practical first step. The Senate proposal sets a 10-year schedule for establishing a unit-level tracing system, phasing in lot-level serialization over seven years, followed by adoption of product verification at the unit level. The current House bill has no provision for a future shift to unit-level tracking, a shortcoming that was roundly criticized by Democrats at an April E&C Committee hearing. At a minimum, FDA and Democrats want to delay state pre-emption until some kind of national tracking system is fully operational.  

Pharmaceutical manufacturers such as Johnson & Johnson are moving to comply with the California law by applying standardized, serialized two-dimensional bar codes to packages and establishing processes to exchange serialized data with distributors and pharmacies, explained J&J Vice-President Michael Rose at the House hearing. However, these efforts would be wasted, Rose noted, if other states adopt different standards. "What we need is a clear end-game," said Rose, "where the goal posts are fixed." 

E&C Chairman Fred Upton (R-Mich) initiated efforts to "mark up" the Republican-backed bill with an eye to approving legislation by August 2013. Without some provision for unit-level serialization in the not-to-distant future, though, Congress probably will reject drug-tracking legislation in 2013.

Washington editor, Chevy Chase, MD, 301.656.4634, 

Regulatory Beat

Bills to regulate drug compounding and establish a national track and trace system face political and policy differences.

Congress Considers Legislation to Secure Drug Supply Chain

New drug approvals by FDA continued their upward advance in 2012, but CMOs didn't benefit much from the improvement. The data suggest that the market share of dose CMOs may have peaked. 

In 2012, FDA's Center for Drug Evaluation and Research (CDER), which approves new small-molecule and biologic therapeutic drugs, approved 101 new drug applications (NDAs). This level was on par with the 102 new drugs approved in 2011 and continues the recovery in NDA approvals that started in 2008 (see 

Figure 1: New drug application (NDA) approvals, 2006-2012. NME is new molecular entity. (ALL FIGURES COURTESY OF AUTHOR)			

The composition of the new approvals was particularly noteworthy. Of the 101 NDA approvals, 39 were for new molecular entities (NMEs) (i.e., drugs containing an API that was approved for the first time). The NMEs included 10 biologics and 28 small molecule drugs. This level was the most NME approvals in more than seven years. 

There were 62 non-NME drugs approved (i.e., drugs containing a previously approved API). Of those, 47 were approved via the 505(b)(2) route, which provides for a simplified approval process for new formulations of previously approved drugs. The 505(b)(2) process is particularly popular with specialty pharmaceutical and generics-drug companies because it is a lower-cost and lower-risk process for developing new drugs than developing NMEs.  

While the approvals trend grew stronger, the propensity for outsourcing the manufacturing of these new drugs remained flat. Overall, dose manufacturing was outsourced for 42% of the NDAs approved in 2012, which was consistent with the 41% average for the previous six-year period (see 

).  Both NMEs and non-NMEs were outsourced at the 42% rate. 

Figure 2: Share of new drug application (NDA) approvals outsourced, 2006-2012. NME is new molecular entity.			

The propensity to outsource was largely a function of the nature of the approval and the size of the company getting the approval. Global and mid-size biopharma companies were more likely to outsource their non-NMEs than their NMEs; the global biopharma companies did not outsource dose manufacturing for any of their biologics approvals, but did outsource some of their small-molecule approvals. Small companies outsourced dose manufacture for most of their new approvals, both NME and non-NME, including 100% of their biologic approvals. As one would expect, generic-drug companies outsourced few of their new approvals. 

A total of 28 different dose CMOs benefited from new product approvals in 2012. Only six had more than one approval, with Catalent (six new approvals) and Patheon (four new approvals) leading the way.  

PharmSource analysis of eight years of FDA approvals data suggests that the acceptance of the CMO business model and its penetration of the biopharmaceutical industry have remained relatively unchanged throughout most of the past decade. NME dose-form outsourcing has remained relatively constant for the past seven years as the industry is governed by two basic truths: smaller companies have a strong tendency to outsource while global biopharma companies have a strong preference to keep products in-house.  

Among global bio/pharma companies, attitudes and strategies regarding contract manufacturing appear to be well entrenched. Out of the 22 global biopharma companies, nine companies—including Abbott/Abbvie, Astellas, Bayer, and Novo Nordisk—outsourced none of their new NDA approvals during the 2005

2012 period. On the positive side, four companies have outsourced 50% or more of their NDA approvals received during the past eight years, and another four have outsourced 30% or more of their approvals. Unfortunately, six of the eight companies have averaged less than one approval per year over the period.  

The data on outsourcing of recent NDA approvals must be analyzed carefully because the majority of the contracts for these products were signed three-to-five years ago (i.e., in 2007

2009). Given the long cycles between contract signings and product approvals, strategy changes triggered by the 2008-2009 financial crisis and the patent cliff probably are not yet reflected in the manufacturing arrangements of recently approved products. 

Nevertheless, it does appear that outsourcing's share of dose manufacturing is stuck in the 40

45% range, and further penetration may be difficult to achieve. Global biopharmaceutical companies have been shrinking their manufacturing networks and shrinking their product pipelines, but they are investing in captive biologics manufacturing capacity and building new manufacturing facilities to serve the growing emerging markets. Among smaller companies, those companies that develop new biologics may be unable to afford their own sterile manufacturing facilities, but small companies developing solid-dose products face a much lower capital expenditure for owning captive capacity.   

CMO executives like to proclaim that outsourcing is growing, and so long as the number of new product approvals continues to rise, they will be right. But just as a rising tide lifts all boats, a receding tide can leave many of them beached. The large number of CMOs receiving approvals again highlights the highly fragmented nature of the sector; so many CMOs have received just a few or no approvals that one wonders how they can stay in business. 

The battle for market share among CMOs is getting intense, and we sense that customers are able to drive more favorable terms, including lower prices and other concessions. A number of major CMOs have accepted this reality by turning their efforts increasingly to proprietary products. We continue to believe that the CMO industry is headed for a period of consolidation. 

 is president of PharmSource Information Services, Inc., and publisher of 

,  tel. 703.383.4903,  Twitter@JimPharmSource, 

Outsourcing Insights

Approvals of new drugs are on an upward swing, but only a few CMOs are benefiting.

Drug Approval Trends Don't Extend to CMOs

Pharmaceutical companies applying for marketing approval of their products in Europe are now required to provide the region's regulatory authority with documented evidence that they are using a process that consistently produces their medicines at the correct specifications and quality standards. At the moment, companies have the option of providing regulators with the details of a process validation itself or of how they intend to carry one out. However, it is likely that the requirements will become more stringent with details of process validations being demanded not only in applications for marketing authorizations but also during the post-marketing phase. 

"Process validation is an evolving landscape with a strategy being used throughout the lifetime of a product," said Brendan Hughes, an industry participant from Bristol-Myers Squibb at the expert workshop on validation of biopharmaceutical active substances in April at the London headquarters of the European Medicines Agency, the European Union's central licensing authority. 

One of the main driving forces behind this move, which requires drug companies to provide more information on their processes, is an EMA-led policy of gathering as much data possible on the benefits  risks of medicines from multiple sources including their methods of manufacture. Among the new sources of knowledge is data generated by the EU's new pharmacovigilance legislation that came into effect in July 2012. The aim is to build up an extended database on all authorized medicines, including post-marketing information on possible adverse reactions and manufacturing issues. The database complements an expanded one on GMP—called EudraGMP—containing information yielded by a new legislative requirement on GMP in the production of APIs.  

The new legislative initiatives need to be "systematically utilized and further integrated to deliver continuous knowledge generation," said Peter Arlett, EMA's head of pharmacovigilance and risk management, and Tomas Salmonson, chair of the committee for medicinal products for human use (CHMP), in a joint article in the agency's latest annual report published in April. They added that "this concept of continuous knowledge generation is enabled by a lifecycle approach to data collection, and improved scientific and regulatory methods."

With process validation, EMA wants to use, in particular, a lifecycle system for new technologies being applied in the manufacture of advanced therapies. Last year, after detailed process validation, it approved Glybera, a gene therapy for treatment of the rare inherited disorder lipoprotein lipase, developed by the small Dutch company UiQure. Glybera was the first gene therapy to be authorized by EMA and the Western world. Its production process is likely to be scrupulously monitored after the product's launch. According to EMA, the authorization paves "the way for approval of similarly complex medicines in the future, as more gene therapies for rare diseases, personalized medicines, and nanomedicines are on their way." 

In a draft guideline on process validation for dosage-form medicines, issued by EMA a year ago and currently being finalized, the agency said that a manufacturing process should be validated before a product is launched on the market. However, with medicines produced by well-established technologies, details of the validation, which can be based on the traditional validation method of using studies on batch production at the pilot stage, do not have to be placed in the application dossier for authorization. Instead, the data should be held at the manufacturing site to be made available, if necessary, for inspection. With biopharmaceuticals and other "non-standard method" of production as well as specialized products such as modified-release preparation, details of the validation, which should be made with verification data at the production-scale level, should be included in the application dossier. 

During the post-authorization phase, validation is seen in the guideline as a means of monitoring and evaluating the processes in a continuous manner. "It is a science- and risk-based approach to verify and demonstrate that a process operating within the predefined specified parameters consistently produces material that meets all its critical quality attributes (CQAs)," the guideline says. 

After a consultation on the draft guideline, one key issue being decided by EMA is the scope of process validation, which comprises an evaluation and verification stage. It was generally agreed that continuous process verification (CPV) should be a key component of the lifecycle monitoring of pharmaceutical manufacturing. "These concepts (with continuous process verification) are new but they are acceptable approaches," said an official at the UK's medicines and healthcare products regulatory agency (MHRA).  

Under their GMP obligations, pharmaceutical manufacturers should be regularly checking their production processes anyway. "Regardless of the nature of the medicinal product, in accordance with GMP requirements, processes and procedures should periodically undergo critical re-evaluation, including revalidation as necessary, to ensure that they remain capable of achieving the intended results," said the MHRA official. 

At the EMA's expert workshop on process validation of biopharmaceutical active substances, the difference between continuous and continued evaluation was explained in the context of GMP adherence. While continued verification is done with interruptions, continuous verification is carried out without stopping, said Kowid Ho, a member of the EMA's biologics working party (BWP), which is working on a guideline for biotechnology-derived active substances. An enabler with continued verification is GMP compliance, while with continuous verification, the enabler is quality-by-design tools such as process analytical technology (PAT) and in-line and at-line controls, added Ho, who is a biological products specialist at the French national medicines agency (ANSM). Hughes however, considered that a continued process verification can include some or all of the data sources used in the CPV procedure.  

One difference between the two is that with continuous verification, the data are included in the application filing while continued verification is a basis for a prospective proposal. It may be described in the application filing but the main purpose of the data from continued verification is to show GMP compliance. The draft guideline on process validation of dosage-form medicines stresses the distinction between them. Although it says that continuous process verification depends strongly on compliance with GMP principles, its data are separate from that applying to GMP matters that are dealt with by GMP inspectors, the guideline says.  

CPV is also a method that can be introduced at any time in the lifetime of a product. It can be used to revalidate commercialized products as part of the existing regulated system of post-authorization process changes, or it can be used to support an improvement program throughout the remainder of a product's lifecycle, according to the guideline. 

A key aim of CPV is that it should not only be a means of verifying the validity of an original process validation but also for achieving greater knowledge of existing and new production methods. "It can be used when extensive process knowledge has (already) been gained through commercial manufacturing experience," said Ho. For the European regulators, the long-term objective behind lifetime process validation is that medicine manufacturers would achieve full understanding of their production technologies. It marks an important addition to the ways of ensuring that medicines meet the highest quality standards. 

 is a freelance writer based in Essex, UK, 

European Beat

A science- and risk-based approach to verify and demonstrate that a process operating within predefined specified parameters consistently produces material that meets all its critical quality attributes.

A Lifecycle Approach to Process Validation

Maciej Frolow/Getty ImagesPharmaceutical product development activities are highly inter-connected in nature. For parenteral drug products, the prefilled syringe is generally considered a challenging container closure system, particularly in the case of vaccines with complex product design requirements. The product design phase involves integration of prefilled syringe as a crucial part of the target product profile (TPP) when considering the complex health policy and user requirements imposed by different global geographic regions and regulatory authorities. The product development phase focuses on the prefilled syringe as an integral part of the vaccine drug product. Particular attention needs to focus on multiple syringe component attributes such as silicone oil and tungsten that may create potential interactions with the diverse molecular properties of antigens. Emphasis of the product operation phase is to link prefilled syringes to the product performance per design requirements and supplier process capability and quality control. Lastly, processing and supplier quality control must be implemented within regulatory compliance framework to ensure delivery of quality vaccine product to patients.  

VACCINE PRODUCT DEVELOPMENT IN PREFILLED SYRINGES—DRIVERS AND COMPLEXITY 

The goal of pharmaceutical product development is to design and establish the formulation composition and its manufacturing process to consistently deliver a drug product with all the appropriate quality attributes required for its intended efficacy and safety profile. A systematic approach according to the quality-by-design (QbD) concept is applied to achieve both the information and material deliverables during the product development lifecycle (1). Before work begins on the development of a new product, it is crucial to clearly define the quality attributes of the product with consideration of the end user's needs in mind, commonly referred to as the target product profile (TPP) in the pharmaceutical industry. A TPP can be used to facilitate discussions with regulators regarding the anticipated label claims for a product (2). It can also be used for the private sector market, to help determine competition and associated pricing strategies (3, 4). Alternatively in the case of vaccines, a TPP can be used as a tool to engage and align with public health policy organization by working together to achieve the intended health impact (4, 5). 			

The definition of TPP according to the target disease/health policy and user requirement drives the design of the dosage form with selection of the primary container-closure system as an integral aspect to meet the delivery requirement. Drug products packaged in prefilled syringes essentially remove the withdrawal step from another container, such as a vial or ampoule, prior to administration. As a result, prefilled syringes offer a more convenient alternative to vials for the preparation and administration of injectable drugs. This results in improved provider/patient convenience and compliance, as well as product differentiation when combined with auto-injector delivery devices. 

There are many drivers and good reasons to have vaccines in the prefilled syringe presentation. First and foremost vaccines are complex biological entities; therefore, they must be administered by injection due to the lack of significant advance in alternative delivery technologies. From the technical point of view, one can imagine it is absolutely crucial to reduce the risk of wrong dose and also better dose precision; therefore, one can see the advantages of prefilled syringe as compared to vials. From a practical point of view, vaccines are sometimes driven by public health outbreaks because many doses could be given in a crowded setting, allowing simple administration with limited manipulation. This provides for less probability of handling errors in a prefilled syringe presentation, which is preferred. Lastly, there is a different economic factor than for example biologics and is driven by key stakeholders in the public health sector. The minimal overfill in a prefilled syringe as opposed to vial can also provide an economic advantage, because costs per unit must be low. In summary, there are clear scientific, practical, and economical drivers for developing vaccines products in prefilled syringes. 

Vaccine product development is complex in many aspects. First, vaccine products are prophylactic as opposed to therapeutic, and more often than not, the target population is children and pregnant women, so the regulatory standard is high. Second, the product types are diverse such as recombinant proteins, glycoconjugates, virus-like particles, attenuated viruses, and live viruses. The dosing requirement is also challenging, in that doses are typically very small. Multiple antigens are often combined to reduce the number of injections, and adjuvants are added in some cases to boost the immune response. Lastly, the complex properties and interaction with prefilled syringe results in an acute challenge to vaccine manufacturers.  

CHALLENGES OF VACCINE PRODUCT DEVELOPMENT IN PREFILLED SYRINGES

The prefilled syringe is a complex system where the component characteristics often depend on the material of construction and processing conditions, which results in variability of the component attributes such as silicone oil level and distribution, as well as residual tungsten. Specifically, silicone oil and tungsten has been implicated in the induction of protein aggregation (6). It is also important to understand whether aggregation is a prerequisite for a cascade phenomenon leading to the visible particulate formation, which is not acceptable for a parenteral product. Not only does this create stability issues, proteinaceous aggregates presented in a highly arrayed structure of sub-visible size range, such as might be found in large non-denatured aggregate species, have been known to potentially interact with the immune system to enhance immune responses (7, 8). This interaction causes great concern and has been critically scrutinized by the regulatory bodies for therapeutic proteins. However, this should not be falsely perceived as a "hand waving favorable" immunogenicity risk assessment for vaccine products. It is categorically essential to ensure that product quality attributes including aggregate species, must be under strict control to demonstrate the intended immune response of the vaccine for the target disease and patient population. As stated earlier, the prophylactic nature of vaccine products impose a higher and more rigorous regulatory standard.  

In particular, the glass syringe barrel contains silicone oil for functionality purposes, which could migrate into the drug product solution during shelf-life storage. When protein interacts with silicone oil, there are potentially two phenomena that could lead to visible particulates formation. First, hydrophobic interaction could enhance protein aggregation as a prerequisite for visible particulates formation (6). On the other hand, the dispersed silicone oil droplets, although at low level, may be charged dependent on the formulation condition. The charge effect could lead to colloidal instability and flocculation of the silicone oil emulsion together with the protein, which has been reported in literature (9). The protein and silicone oil droplets are quite different in size microscopically, which can be characterized by a recently developed new technique of suspended microchannel resonator (SMR) (10). Silicone oil droplets are charged particles where surface properties have a large effect on emulsion stability. Both the concentration (i.e., quantity) and total surface area (i.e., number and size of oil droplets) are critical attributes to understand the protein silicone interaction phenomenon. Depending on the isoelectric point of the protein and pH of formulation, protein adsorption can change the surface charge properties, and therefore, kinetic instability of the silicone oil emulsion. As a result, the flocculation and coalescence of protein adsorbed silicone oil droplets can lead to the formation of visible particulates. This potential mechanism of action is illustrated in 

Figure 1: Silicone interaction and formation of visible particulates. (ALL FIGURES COURTESY OF AUTHORS)			

These concepts are also highly relevant in the case of a complex vaccine product, for example, glycoconjugates. Effective immunization against encapsulated bacteria can be achieved by a type of vaccine based on oligosaccharide conjugated to a carrier protein, for example CRM197, a non-toxic mutant of diphtheria toxin (11). For a particular target disease, different serotypes with different polysaccharides would be needed to achieve majority coverage of the population. For example, serogroups A, B, C, W135, Y, and recently X account for the majority of meningococcal disease in humans (12). Bacterial polysaccharides are high molecular weight and mostly negative-charged carbohydrate molecules. Semi-synthetic glycoconjugates are complex molecules composed of protein and carbohydrate moieties linked together by chemical reactions. The conjugation reactions involve different chemistry and, therefore, different linking sites on the surface of the protein and along the saccharide chain. Moreover, the polysaccharides are high molecular weight carbohydrate moieties with some degree of polydispersion, which increases the heterogeneity of the resulting glycoconjugates.  

The polysaccharides are mostly negatively charged, and there is also significant charge heterogeneity of these glycoconjugate vaccines. 

 shows an example of the charge heterogeneity of three glycoconjugate vaccines as compared to the carrier protein measured by pI. The pI is a well-defined single band for the carrier protein but there is a significant dispersion of isoelectic point (pI) representing charge heterogeneity for the three different glycoconjugates. Each of these highly charge heterogeneous molecules are expected to interact with silicone in a different manner both individually in a monovalent and collectively in a trivalent formulation, which could lead to decrease colloidal stability of the low concentration silicone oil emulsion in a prefilled syringe. It is likely that visible particulates form when the silicone oil droplets associated with these glycoconjugates coalescence.  

Figure 2: Charge heterogeneity of three glycoconjugates A, B, C and carrier protein as control measured by isoelectric focusing gel.			

At present, there is little reported in the literature on systematic and comprehensive characterization of silicone glycoconjugate interactions under a variety of formulation conditions to support the successful development of these types of important vaccine products. On the other hand, it is also important to consider the silicone variability associated with the prefilled syringe components, such as the intra- and inter-batch variability plus the migration during storage before product is filled. After the product is filled, product storage, handling, shipment, agitation, and excursion all contribute to potential significant intra- and inter-batch variability.  

In summary, a vaccine product such as glycoconjugate has additional complexity and challenges for prefilled syringe development when compared to therapeutic proteins. It is logical and reasonable to recognize that a large part of development effort should focus on understanding the components, and a standardized toolbox can help build such understanding and a better strategy to control the variability.   

INTEGRATED PREFILLED SYRINGE TOOLBOX FOR VACCINE DEVELOPMENT

Successful development of a vaccine product in prefilled syringes requires careful evaluation of the interaction between the formulation and primary packaging components. In support of each vaccine, a QbD approach will be used to design systematic product and process development studies and ensure a comprehensive data package. It is, therefore, crucial that a platform approach for these development efforts be implemented, in which there is detailed characterization and fundamental understanding of the various component attributes and associated variability within the platform prefilled syringe systems. In addition, the prefilled syringe system selected for the platform approach must also fit well with the existing manufacturing and production capability. To achieve a robust and flexible prefilled syringe platform, it is also beneficial to form a strategic alliance with a reliable supplier that has a good reputation of quality control. Processing and quality control compliance are vital for a successful vaccine product development and subsequent licensure. In summary, we propose a holistic and integrated approach to focus on the linkage of prefilled syringe in the following areas: 					

Target disease/health policy/user requirement

Manufacturing process (site and equipment)

Regulatory and quality compliance requirement.

It is important to recognize there is significant interdependence between these areas, where an integrated platform toolbox is warranted and these six aspects are connected into the four phases of product design, development, operation, and control (

). The product design phase involves integration of the prefilled syringe as a crucial part when considering the complex health policy and user requirements imposed by different global geographic regions as well as private market competition. The product development phase focuses on the prefilled syringe as an integral part of the vaccine product due to the multiple contacts and potential interactions with the diverse molecular properties of antigens. In particular, particles characterization pertinent to silicone interactions is crucial because vaccines are prophylactic treatment to elicit an immune response before sick.  

Figure 3: Integrated platform toolbox approach for vaccine product development in prefilled syringe.			

The emphasis of product operation phase is to link the prefilled syringe to the product performance per design requirements and supplier process capability and quality control. As a result, a key focus will be on supplier collaboration to understand their process capability and improvements. Lastly, quality control of supplier with respect to incoming components, as well as manufacturing process with respect to both site and equipment, must be implemented with periodic review mechanism within the regulatory compliance framework to assure quality vaccine products delivered to the patients. 

In addition, the six areas are divided into nine categories with detail attributes under each category based on technical considerations, prior project experience, and learning. These attributes can be summarized in a fishbone diagram, as shown in 

, to form the basis of risk assessment to select and implement different feasible options for a standard toolbox approach. In summary, the standard work stream, when combined with a toolbox approach, will drive down the development risk with information that allows plug and play, as well as supply of standardized component material that result in lower cost of goods. Furthermore, the platform approach can be improved and is expandable with accumulated product experience in the future after joint efforts with a formulation group and suppliers.  

Figure 4: Fishbone diagram of detail attributes as basis for risk assessment for selection and implementation of prefilled syringe toolbox.			

The benefit of using a standard set of prefilled syringe components consistently for a variety of products is that a solid and robust data package can be established to support licensure application. These categories of information include: 					

Description, general information, material of construction, method of manufacture 

Suitability according to the FDA container closure guidance document which encompasses protection, compatibility, safety and performance 

The quality control aspects such as incoming specifications, industry standards, etc. 

Stability results, for example, will reveal some of the common stability issues and challenges depending on the product types, etc. 

Manufacturability when new products in the same set of prefilled syringe are being transferred to production facility, where deep process knowledge of the platform prefilled syringe systems have been accumulated with definitive enhanced production efficiency and quality control.

This is important because it's expected to provide all of this information in a submission as summarized in 

Table I: General submission information requirement.			

A holistic and integrated prefilled syringe platform toolbox approach will streamline development with higher probability of success even in the complex and challenging case of vaccine products. More importantly, such an approach is not only beneficial to technical challenges, but also provides economic benefits. We sincerely hope that the cost of innovation for a new prefilled syringe system is not so prohibitive that vaccine products cannot afford to achieve the intended health impact to society. 

We like to thank Anna Coslovi and Francesca Beccai for their preliminary results to characterize the charge heterogeneity of glycoconjugate vaccines.   

 is senior scientific associate, all at Pharmaceutical Sciences, Novartis Vaccines and Diagnostics, Inc., 

www.pda.org/Home-Page-Content/CMC-VWG-A-VAX.aspx

 6. L.S. Jones, L. S., A. Kaufmann and C.R. Middaugh, 

An integrated focus on product design, development, operation, and control.

An Integrated Prefilled Syringe Platform Approach for Vaccine Development

The Taiwanese government engages in regulatory science in a move to boost its pharmaceutical sector.

Taiwan is now a step closer to its goal to "promote the administration and education of pharmaceutical regulation" with the establishment of a new Center for Pharmaceutical Regulatory Science in the country by the National Cheng Kung University (NCKU). The center aims to promote pharmaceutical education and cultivate personnel training for pharmaceutical administration. Its mission also includes conducting research on pharmaceutical regulation and promoting international collaboration efforts, says Professor Yea-Huei Kao Yang, director of the center and professor of the Institute of Clinical Pharmacy and Pharmaceutical Sciences at NCKU.  

Photo Credit: Hung Chei/Flickr/Getty Images			

Taiwan's regulatory system is comparable to that in America and Western Europe. In 2007, a health-technology assessment system was introduced for the pricing and reimbursement of new drugs. Taiwan also established its Food and Drug Administration (FDA) in January 2010 with a clear objective to establish a regulatory environment with drug-review mechanisms of international standards to run pharmaceutical affairs. Looking ahead to 2014, the agency commits to implementing the Pharmaceutical Inspection Convention Scheme (PIC/S) to help improve the quality of local medicines and upgrade production facilities to enable quicker penetration of its medicines into foreign markets. 

"The setting up of a center for pharmaceutical regulatory science in Taiwan's NCKU, perhaps the first such center in Asia Pacific, mirrors the increasing importance that regulatory science is gaining among the regulatory agencies globally," says William Lee, senior director and head of regulatory strategy of the strategic drug development Asia unit at Quintiles. 

Kao adds, "Its establishment is significant because it paves a clearer direction for Taiwan's pharmaceutical and healthcare industry as a whole. Overall, western and local industry players are positive in regard to this new center and believe that NCKU is taking a first step toward improving the pharmaceutical and healthcare landscape in Taiwan. The center, through its project base case studies with school professors, industry physicians, and related experts, aims to open up the communication between regulators and consumers. By its goal for transparent pharmaceutical management, the quality standard in the industry and the accessibility of information would positively improve." 

According to Geeta Dhanoa, Frost and Sullivan's associate director of healthcare practice for Asia Pacific, "the preparation of the whitepaper on food and drug policy and nonprescription medicines management policy is the priority for the center, which will serve as a national platform for the government, the academia, and the industry to integrate the resources and talents." However, these initiatives are in the initial stage and the effect will be seen after the formalization of the new drug-pricing policy and reimbursement scheme. Hopefully, they would receive positive response from industry players to eliminate the regulatory hurdles so that drug registration can be improved, and to provide a conducive environment for the market participants to grow, says Dhanoa. 

The initiatives are expected to benefit industry players. "It is expected that the approved pharmaceutical products are safer, following safety and ethical norms," Dhanoa explains. The center would also ensure that approvals for products are obtained more quickly or are manufactured in such a way as to decrease potential patient and safety problems. 

"In a competitive environment, it is crucial for pharmaceutical products to reach the market in a short span of time. Hence, the regulatory center is expected to explore the shortest route and timeframe to put these products on the market, and support the lifecycle management of the products. This will prove to be advantageous for start-up and local firms in Taiwan," says Dhanoa.  

In addition, the approval process for new drug and generic-drug manufacturing and marketing applications would include a review of the manufacturer's compliance with GMP as set by Taiwan's FDA. Based on standard operating procedures and guidelines, the regulatory center would determine whether the firm has the necessary facilities, equipment, and skills to manufacture the new drug for which it has applied for approval. Decisions regarding compliance with regulations are likely to be based on inspection of the facilities and sample analyses, which are expected to affect foreign firms entering the market. 

The impact of the center's establishment can be viewed from both short- and long-term perspectives according to Lee. From a short-term perspective, one can expect an increase in cooperation and communication in academic research on pharmaceutical regulation that would promote collaboration between local regulatory agencies as well as foreign regulatory agencies and academic institutions. Such exchanges could result in a convergence of approaches to pharmaceutical regulations. Additionally, the Taiwan pharmaceutical industry could potentially see a shift in regulatory agencies taking a more science-based approach to the assessment of safety, efficacy, quality, and performance of regulated products.  

Looking forward, this development may well position the Taiwanese regulatory agency as a forward-looking agency, particularly in North Asia. "As a platform to promote regulatory science within the pharmaceutical industry, the center would show the local region as well as the surrounding regions its aim to improve the overall efficiency of the industry. The movement would promote regulatory science through local and regional collaboration," Kao says.  

—Jane Wan is a freelance writer based in Singapore

Global Report

Report from Taiwan

Disposable bags are widely used in the biotechnology industry. The two main purposes are to store cell-culture media and to grow cells for inoculum or production. Several groups have reported growth inhibition resulting from the use of such products. This report shows independent data from four companies, using several different cell lines and growth media, and suggests a method that can be implemented for quality control at disposable-bag vendors.

Photo Credit: Nicholas Rigg/Getty ImagesRecently, a group of engineers and scientists within the cell-culture process-development community convened the first inaugural Cell-Culture Industry Forum (CCIF), which was held in Longmont, Colorado, in February 2011. More than 30 individuals from nine companies met over three days to present topics related to the common challenges and problems within the large-scale cell-culture industry. A highlighted theme at the first forum was the observation of cell growth inhibition, presumably resulting from the use of disposable bags. Disposables are widely used in the biotechnology industry for numerous bioprocessing functions. Extractables and leachables from disposables are frequently discussed (1). Two of the functions of disposable bags in the industry are to store cell-culture media and to grow cells within the bags at all steps of cell culture-based manufacturing. At the meeting, as well as described in other forums (2–6), it was clear that cell growth was sometimes affected by the use of disposables for these applications. A subteam was formed after the CCIF adjourned to further discuss and act upon these observations.  			

This paper describes collaboration in which four of the participating CCIF companies jointly assessed cell growth inhibition resulting from the use of disposable cell-culture bags (hereafter referred to as bags). The assessments are meant to uncover subtle effects on cell growth when medium is warmed in bags prior to use in cell-culture steps. Developing a widely applicable growth test is not a trivial exercise—it should be cell line- and media-independent so that vendors can apply it with confidence and avoid unwanted false-positive results. To that end, data are shown from these four companies, encompassing many different cell lines grown in four independent and proprietary media in which cell growth effects are apparent when water used for media preparation is warmed in the bags prior to use. The method described has leveraged strategies developed at each company as part of their ongoing work in disposable-bag selection.  It is implementable across bag vendors and can potentially uncover problematic bag lots as well as identify when bag-film changes lead to inhibition of cell growth. 

The data shown here are derived from three bag vendors. For all graphs, Vendors A, B, and C are the same vendors among each company's figures. Each company used the bag(s) in use at their facility at the time of testing. The bags are used for either media storage (and warming) or cell-culture steps (seed train, scale up, and production) in the overall bioprocess.  

Preparation of media used  in cell-growth testing 

The water used to prepare media was from the same source as used to prepare cell-culture media for normal process development and/or pilot-plant operations.  

Companies 1 and 2 employed the following method. Sterilized water was introduced into bags at the lowest volume-to-surface area ratio normally employed for cell bag (growth in bags) applications. If any company didn't normally use bags for growth steps (i.e., they only use bags for media storage), they added water at a low volume-to-surface area ratio, similar to that of a company who would use bags for such an application. Water was incubated in bags for four days at 37°C. As a control, water was incubated in glass bottles for four days at 37°C. After incubation, both water types were used to prepare cell-culture media at Companies 1 and 2 according to their normal operating procedures. Following preparation, the media were sterile-filtered (0.1 μm pore size rating filters of either hydrophilic polyvinylidene fluoride [PVDF] or polyethersulfone [PES] filter media) into and stored in glass or Nalgene-type bottles. Media were then held at 2–8°C until used for cell culture-growth testing, up to 30 days. Company 2 also held prepared media derived from water incubation in bags at 2–8°C in glass bottles for 16 weeks. This case is labeled "aged medium" for the data of Company 2. Company 3 used a similar method to Company 1 and 2, except that the water incubation temperature was 36.5°C, and the control medium was prepared using the same cell culture-grade water according to the standard preparation method at the company without four days' incubation at 36.5°C.  

Company 4 modified the approach of Companies 1–3 slightly. Medium was sterile-filtered at a low media-to-bag area ratio into either a glass flask (control) or into a 10-L bag from three vendors. The containers were incubated at 37°C for three days prior to the media being used in the growth assessments.  

The data shown here represent at least four independent media. Because of the proprietary nature of these media, it is unknown among the authors how similar or unique they are to one another. 

The second step consisted of passaging cells using the incubated media. This was done by transferring incubated media into separate shake flasks, inoculating with cells, and passaging three times, each passage lasting 3–4 days. This procedure was used to test films from three different vendors, each run in at least duplicate cultures. 

All companies used at least one in-house Chinese hamster ovary (CHO) cell line that had been transfected to produce a protein of interest. CHO lines used dihydrofolate reductase (DHFR [-]) or glutamine synthetase (GS) selection systems. Company 2 also performed the work with an NS0 cell line. The cell lines in some cases were already known to be affected by this bag application as discovered by those companies previously. In some cases, the cell lines were tested for growth inhibition for the first time. All cell lines used for these studies are believed to represent typical production lines within each company. 

Prior to cell-growth testing, each cell line was grown in media identical to or similar to that of the actual test media composition. Cells were seeded into shake flasks for the first passage in test media following a low-g spin and resuspension step except for Company 3, where cultures were passaged without this step. The seeding densities used were in the low end of the range used at each company. Cultures were then maintained for at least 10 generations (doublings) over three passages for the control condition (water incubated in glass bottles), or for test conditions where there was cell growth. Each passage lasted 3 or 4 days. At each passage, the cells were diluted to the same seeding density as for the initial passage in test media (i.e., there were no fixed split ratios). Mixing and CO

 gas levels followed each company's standard practice for the cell line being tested. Cell density and viability measurements were made using automated image analyzers that employ Trypan blue staining.  

Cell growth levels and viabilities were compared between bag-incubated water or media, and glass bottle-incubated water or media preparations. Cell growth is shown as a multiple of the starting passage density and is labeled as normalized viable cell density. In all cases, actual viabilities are shown. Data points for cell density and viability in each figure are the average of at least two shake flask cultures.  

shows the cell growth and viability for a CHO cell line previously observed at Company 1 to have growth inhibition when media was stored and warmed in disposable bags from Vendor A, as well as from another CHO line that did not exhibit growth inhibition. Cells grew to the highest densities when media were prepared from water incubated in glass bottles (

, Glass incubated water). One lot of bags from Vendor A resulted in limited growth inhibition for each CHO line (Lot 1) while another lot (Lot 2) affected growth significantly during passages one and two, where viability was also lower than other cases (

, Vendor A incubated water, CHO Line 2, Bag Lot 2).  

Figure 1: Normalized cell growth and viability of Chinese hamster ovary (CHO) cell lines-results from Company 1. (ALL FIGURES COURTESY OF AUTHORS)			

shows the results from Company 2 for an NS0 line and a CHO line. The NS0 cell line experienced a severe impact on growth and viability when cultured in medium derived from one lot of bag-incubated water (

, Vendor B incubated water, NS0 Line, Bag Lot 1). This same medium, when stored at 2–8°C for an additional duration (16 weeks in total) in a glass bottle, still maintained its growth inhibitive properties on this cell line (

, Vendor B incubated water, NS0 Line, Bag Lot 1, Aged Medium). However, this bag did not exhibit any growth inhibitive effects on the CHO cell line evaluated (

, Vendor B incubated water, CHO Line, Bag Lot 1). A second lot of bag-incubated water was able to support cell growth in the sensitive NS0 cell line (

, Vendor B incubated water, NS0 Line, Bag Lot 2). 

Figure 2: Normalized cell growth and viability of NS0 and Chinese hamster ovary (CHO) cell lines-results from Company 2. 			

Company 3 assessed cell growth and viability on one CHO cell line (

) using two vendors and two lots of bags from each vendor. Growth was inhibited by nearly 50% when water incubated in Vendor A bags was used to make medium (

, Vendor A incubated water). Cell viabilities were not affected, however. For the cell line tested, there were no inhibition effects on cell growth and viability observed when using medium prepared from water incubated in Vendor B bags for both lots of bags tested. 

Figure 3: Normalized cell growth and viability of Chinese hamster ovary (CHO) cell lines-results from Company 3. 			

Company 4 assessed cell growth and viability in media incubated in bags from three vendors (

). Vendor C bags led to the most pronounced growth and viability effects. In the case of media held in Vendor C bags, this CHO line did not grow at all (

, Vendor C incubated water). Vendor A bags, shown to inhibit CHO cell growth in a cell line from Company 1 (

), led to 60–80% growth inhibition while viability was less affected. Vendor B bags did not lead to any pronounced growth or viability effects. 

Figure 4: Normalized cell growth and viability of Chinese hamster ovary (CHO) cell lines-results from Company 4.			

Disposable bags used in cell-culture applications have complex manufacturing processes. Polymeric films in many cases are sourced from secondary vendors where a similarly complex manufacturing environment may exist. Bag assemblers may not have detailed knowledge of film manufacturing methods or the authority to influence them if they wished to. Once bags are assembled, they are typically gamma irradiated, which along with the length of shelf-life post-irradiation, is another potential source of variability between manufacturing lots as well as between vendors' products with respect to this effect on cell growth (2).  

The length of media or water warming used for the testing described here is slightly longer than would likely be used in practice. However, the method is useful in uncovering growth inhibition effects and reveals an underlying issue with these products. While industry may not be able to supply vendors with a suitable CHO or NS0 production line to apply this method, the general nature of the effect across multiple CHO lines suggests that a nonproprietary CHO line may be suitable for implementation. However, end-users would likely need some degree of bridging data prior to accepting results generated by a bag vendor using such a CHO cell line. The existence of such bridging data could, in a general sense, also reduce the total in-house effort required at a given end-user to accept bag vendor cell-culture test results in the future. 

To date, the mechanisms that result in cell growth impacts by disposable bags are varied and not completely understood. Medium component adsorption has been identified as one mechanism that can inhibit cell growth in a cholesterol-dependant cell line (7). Cell growth impacts resulting from a specific leachable/extractable have been characterized (8, 9). The cell-based assay was able to identify which disposable bags impacted cell growth and eventually led to identification of the specific leachable inhibiting cell growth. The vendor was then able to optimize the film composition to ensure biocompatibility.  

It cannot be assumed that these are the only mechanisms that can result in inhibition of cell growth. The use of a cell-based assay like those described here can be used to identify where such impacts exist. Once they have been determined, various factors such as raw materials, leachables and extractables, irradiation, storage, and other factors can be systematically investigated. This investigational approach underpinned by a cell-based assay can lead to the identification of the root cause of cell-growth impacts that can be readily addressed by the vendors once understood. The growth test method described is useful in troubleshooting and can be applied proactively as a harmonized first step in improving quality control of these widely used disposable products for both suppliers and customers. 

The problem end-users face is not vendor-specific or fundamentally dependent on the end-users' cell lines or media. The growth test methods described can be applied at bag vendors' own sites. In doing so, vendors may improve the overall understanding and quality control of their disposable products. While some products may not lead to the same observed phenomena, as polymeric film manufacturing or gamma irradiation practices change around them, each vendor could use a test such as this to uncover if those changes have an effect on this particular application. As this issue is still prevalent years after it was first discussed, the authors and the cell culture-engineering community are eager to see the quality-control testing and practices for disposables manufacturers improve.  

When cell-culture medium or the water used to make it are incubated at operating temperature (37°C) in disposable bags prior to use, growth inhibition effects can be observed. These effects are not cell-line, cell-type or cell culture-media specific. The problem is relevant for multiple bag manufacturers. The authors suggest that bag vendors implement the cell-growth test described here as part of their manufacturing quality control and as a means to understand critical film composition attributes and manufacturing controls. The question of what cell lines are best used for this testing remains, but it is believed to be solvable as the effect is observed in multiple CHO lines as well as an NS0 cell line. Having data from such a cell-growth test together with a deeper understanding and control of film composition and manufacture will facilitate adoption and continued use of disposable-bag technology. This knowledge will help ensure robust and predictable performance even through the inevitable changes in bag and bag film manufacturing processes. 

The authors wish to thank Robert Kiss, Masaru Shiratori, Thomas Ryll, Reb Russell, and Richard Schicho for their discussion, review, and comments on this manuscript. Erica Graf and Richard Martel performed cell culture work at Bristol-Myers Squibb Company.  

is a scientist at Process Technical Development, Late Stage Cell Culture, Genentech, a member of the Roche Group, South San Francisco, CA 94110;  

is a scientist, both at Cell Culture Development, Biogen Idec, RTP, NC 27709; 

is manager at Cell Culture Science, Global Manufacturing and Supply, Bristol-Myers Squibb Company, Bloomsbury, NJ 08804; 

 is a principal engineer, both at Amgen, Thousand Oaks, CA 91320.  

* To whom all correspondence should be addressed, 

2.  P. Gammell, "The impact of Lot-to-lot Variability of Disposable Cell Culture Bags on Cell Growth During the Scale-Up of a Mammalian Production Cell Line: Root Cause Analysis and Lessons Learned from the Pipeline," presentation at the Cell Culture Engineering XIII Conference (Scottsdale, AZ, April 2012). 

3.  M. Shiratori, "Recent Experiences with Single-Use Containers Used for Media Storage, Media Handling and Cell Culture," presentation at the IBC 8th International Single-Use Applications for Biopharmaceutical Manufacturing Conference (Long Beach, CA, June 2011). 

4.  M. Shiratori, "Recent Experiences with Single-Use Containers Used for Media Storage, Media Handling and Cell Culture," presentation at the BioProcess International Conference & Exhibition Conference (Long Beach, CA, November 2011). 

5.  J. Wood, "Take II—More Findings and Updates on Our Experiences with Disposable Bags for Cell-culture media Storage," presentation at the IBC's 9th International Single-Use Applications for Biopharmaceutical Manufacturing Conference (San Francisco, CA, June 2012). 

6.  W. Lin and V.L. Tsang, "Risk Mitigation of Mammalian Cell Growth Issues when Using Disposable Cell Culture Bags," presentation at the 245th American Chemical Society National Meeting and Exposition (New Orleans, LA, April 2013). 

A Generic Growth Test Method for Improving Quality Control of Disposables in Industrial Cell Culture

In mid-May, Ranbaxy Laboratories Limited, India's largest pharmaceutical company, pleaded guilty to US Department of Justice felony charges relating to the manufacture and distribution of adulterated drugs made at two of the company's manufacturing facilities in India. The company agreed to pay $500 million—the largest financial penalty paid by a generic pharmaceutical company—for violations of the US Food, Drug and Cosmetic Act (FDCA) and False Claims Act (FCA). 

Ranbaxy agreed to pay a criminal fine and forfeiture totaling $150 million. It will pay another $350 million to settle civil claims that taxpayers paid for substandard drugs used in programs such as Medicare and Medicaid. A Ranbaxy press release explained "a previously disclosed investigation by the US Department of Justice (DOJ) of data integrity and manufacturing processes at certain Ranbaxy facilities in India has been concluded." 

"While we are disappointed by the conduct of the past that led to this investigation, we strongly believe that settling this matter now is in the best interest of all of Ranbaxy's stakeholders," Arun Sawhney, chief executive officer and managing director of Gurgaon, India-based Ranbaxy, said in the statement. "The conclusion of the DOJ investigation does not materially impact our current financial situation or performance." 

Despite its confidence in the bottom line and a tagine of "Trusted Medicines. Healthier Lives." on its website, Ranbaxy USA pleaded guilty to three felony FDCA counts, and four felony counts of knowingly making material false statements to FDA, DOJ reports. The list of infractions shows problems dating to 2003. The company admitted to selling batches of adulterated drugs including Sotret, gabapentin, and ciprofloxacin; had incomplete testing records and inadequate programs to assess the stability characteristics of drugs; and had significant cGMP deviations in the manufacture of certain APIs and finished products.   

The DOJ reports Ranbaxy USA was aware in January 2003 that a batch of Sotret failed an accelerated dissolution stability test but continued to distribute the batch into the US for another 13 months. At various times between June and August 2007, certain batches of gabapentin were testing out-of-specification, had unknown impurities, and would not maintain their expected shelf life; the company did not notify FDA or institute a voluntary recall until October 2007. 

However, the Ranbaxy and DOJ statements tell only part of the story. An investigative report by Fortune magazine details "long-term criminal fraud" at Ranbaxy, and FDA's response to it " ... raises serious questions about whether our government can effectively safeguard a drug supply that last year was 84% generic ..." The article, based on interviews with former Ranbaxy employees, internal documents, regulators, and scientists, describes a pattern of invented data, falsified documents, a lack of testing, and ignorance and disregard of regulatory procedures (1). 

The article reports that some former Ranbaxy executives and FDA inspectors with knowledge of the company's manufacturing practices would not take the company's drugs. Patients did not have insider knowledge of the manufacturing problems, but trusted the medicine and the regulatory channels; some may have paid a high price for the ineffective drugs. That's a violation of trust that the drug industry and FDA must resolve. 

From the Editor

Ranbaxy's $500 million settlement for producing adulterated drugs and fradulent data provides a cautionary tale for patients, FDA, and drug manufacturers.

BioPharm International-06-01-2013

Using Plastic for Parenteral Containers

Congress Considers Legislation to Secure Drug Supply Chain

Drug Approval Trends Don't Extend to CMOs

A Lifecycle Approach to Process Validation

An Integrated Prefilled Syringe Platform Approach for Vaccine Development

Report from Taiwan

A Generic Growth Test Method for Improving Quality Control of Disposables in Industrial Cell Culture

Trust in the Pill Bottle

Flexibility in Biopharmaceutical Manufacturing

Navigating Emerging Markets: Southeast Asia

The Meaning of Metrics

Misconceptions of Maintenance and Reliability: A Biopharmaceutical Industry Survival Guide

BioPharm International, June 2013 Issue (PDF)