Analysis of Silicone Oil in Prefilled Syringes and Biopharmaceutical Drug Products Using High-Performance Liquid Chromatography.

As the packaging of choice for many therapeutic proteins, prefilled syringes have been widely used in biopharmaceutical industry as primary containers, where silicone oil is applied to ensure their proper functionality. Adequate lubrication from sufficient amount of silicone oil and its appropriate distribution across syringe barrels is crucial for successful administration of drug product (DP) from the prefilled syringes; however, silicone oil is also susceptible to leaching from the syringe surface into the formulation with the potential to interact with therapeutic proteins, which could lead to the formation of visible and sub-visible aggregates and/or particles that are potentially immunogenic. Accurate determination and careful control of silicone oil levels in both empty syringes and protein drug products are therefore critical in process development to ensure syringe functionality, drug product quality, and patient safety. On the other hand, analysis of silicone oil can be challenging especially when the analysis is performed on formulated protein drug products, where matrix effects could be significant. It is demonstrated in this study that silicone oil in empty syringes or formulated drug products can be extracted effectively using organic solvents and quantitatively determined using high-performance liquid chromatography (HPLC) coupled with a universal detector. It was also shown that direct extraction of silicone oil from formulated protein drug products can be very challenging, but pretreatment of the protein drug products with pepsin enzymatic digestion facilitated the extraction process, which enabled the analysis of silicone oil in the drug product at low ppm levels.

Chemical and Biophysical Characteristics of Monoclonal Antibody Solutions Containing Aggregates Formed during Metal Catalyzed Oxidation.

PURPOSE: To physicochemically characterize and compare monoclonal antibody (mAb) solutions containing aggregates generated via metal catalyzed oxidation (MCO). METHODS: Two monoclonal IgG2s (mAb1 and mAb2) and one monoclonal IgG1 (rituximab) were exposed to MCO with the copper/ascorbic acid oxidative system, by using several different methods. The products obtained were characterized by complementary techniques for aggregate and particle analysis (from oligomers to micron sized species), and mass spectrometry methods to determine the residual copper content and chemical modifications of the proteins. RESULTS: The particle size distribution and the morphology of the protein aggregates generated were similar for all mAbs, independent of the MCO method used. There were differences in both residual copper content and in chemical modification of specific residues, which appear to be dependent on both the protein sequence and the protocol used. All products showed a significant increase in the levels of oxidized His, Trp, and Met residues, with differences in extent of modification and specific amino acid residues modified. CONCLUSION: The extent of total oxidation and the amino acid residues with the greatest oxidation rate depend on a combination of the MCO method used and the protein sequence.

Ambient analysis of leachable compounds from single-use bioreactors with desorption electrospray ionization time-of-flight mass spectrometry.

RATIONALE: Trace levels of bis(2,4-di-tert-butylphenyl)phosphate (BdtbPP) leaching from single-use bioreactors (SUBs) were recently found to be highly detrimental to mammalian cell growth. The traditional approach to detect the leachable requires time-consuming solvent extraction of SUBs. To assist the qualification of SUBs and/or their manufacturing raw materials in biopharmaceutical development and manufacturing, it is essential to develop a rapid and sensitive analytical approach for detecting this leachable and related compounds, which is described in this study. METHODS: Native films from several commercially available SUBs were directly examined by desorption electrospray ionization (DESI) time-of-flight mass spectrometry (TOFMS) without sample preparation. As a comparison, the same SUBs were also analyzed by high-performance liquid chromatography (HPLC)/ultraviolet (UV) following the solvent extraction. RESULTS: With a suitable spray solvent selected in this study, DESI-TOFMS enabled rapid and sensitive detection of leachable compounds directly from SUBs. Accurate mass measurement from TOFMS allowed ready identification of BdtbPP, its parent analog compound, and other polymer components in the SUBs from their protonated surrogates. The relative abundances of BdtbPP in different SUBs measured by DESI-TOFMS exhibited good correlation with those from the traditional extraction-based approach with HPLC/UV. CONCLUSIONS: A rapid and sensitive approach was developed for direct detection of BdtbPP and other leachables from SUBs using DESI-TOFMS. The results are in high accordance with those from conventional approaches, which indicates the usefulness of the proposed method as a qualification tool for SUBs in biopharmaceutical development and also its great potential in the analysis of extractables/leachables in a wide variety of materials, process components, devices and containers used in the pharmaceutical industry.

Characterization of a Novel Particle in a Pharmaceutical Drug Product.

A previously unreported particle type was observed during routine visual vial inspection of a liquid drug product and suspected to be the result of vial delamination. Delamination is the corrosive attack on the interior surface of a glass container resulting in the release of thin flake-like glass particles, lamellae, into solution. It is a major concern for pharmaceutical companies, especially for parenteral solutions, and drug programs with a high risk for delamination are typically monitored for lamellae formation through long-term stability studies. Although these particles observed resembled lamellae (i.e., thin, reflecting light, buoyant) they were not the result of glass delamination. In this study, the authors describe a previously unreported particle type and provide a detailed comparison with known lamellae exposed to the same drug formulation. The chemical, elemental, and morphological characteristics of the particles and respective vials are described in detail. Overall, the particles' high organic and low silica elemental signature, along with no signs of delamination on the glass vial inner surface demonstrate that this lamellae-like observation is a novel particle form that can be distinguished from lamellae formed from vial glass delamination.

Investigation of a failed DNA assay leads to identification of an unexpected contaminant in a commonly used chromatography buffer.

For mammalian cell-derived recombinant biotherapeutics, controlling host cell DNA levels below a threshold is a regulatory requirement to ensure patient safety. DNA removal during drug substance manufacture is accomplished by a series of chromatography-based purification steps and a qPCR-based analytical method is most used to measure DNA content in the purified drug substance to enable material disposition. While the qPCR approach is mature and its application to DNA measurement is widespread in the industry, it is susceptible to trace levels of process-related contaminants that are carried forward. In this study, we observed failures in spike recovery studies that are an integral component of the qPCR-based DNA testing, suggesting the presence of an inhibitory compound in the sample matrix. We generated hypotheses around the origin of the inhibitory compound and generated multiple sample matrices and deployed a suite of analytical techniques including Raman and NMR spectroscopy to determine the origin and identity of the inhibitory compound. The caustic wash step and depth filter extractables were ruled out as root causes after extensive experimentation and DNA testing. Subsequently, 2-(N-morpholino)ethanesulfonic acid (MES), a buffer used in the chromatography unit operations, was identified as the source of the contaminant. A 500-fold concentration followed by Raman and NMR spectroscopy analysis revealed the identity of the inhibitory compound as polyvinyl sulfone (PVS), an impurity that originates in the MES manufacturing process. We have implemented PVS concentration controls for incoming MES raw material, and our work highlights the need for rigor in raw material qualification and control.

Classification and characterization of therapeutic antibody aggregates.

A host of diverse stress techniques was applied to a monoclonal antibody (IgG(2)) to yield protein particles with varying attributes and morphologies. Aggregated solutions were evaluated for percent aggregation, particle counts, size distribution, morphology, changes in secondary and tertiary structure, surface hydrophobicity, metal content, and reversibility. Chemical modifications were also identified in a separate report (Luo, Q., Joubert, M. K., Stevenson, R., Narhi, L. O., and Wypych, J. (2011) J. Biol. Chem. 286, 25134-25144). Aggregates were categorized into seven discrete classes, based on the traits described. Several additional molecules (from the IgG(1) and IgG(2) subtypes as well as intravenous IgG) were stressed and found to be defined with the same classification system. The mechanism of protein aggregation and the type of aggregate formed depends on the nature of the stress applied. Different IgG molecules appear to aggregate by a similar mechanism under the same applied stress. Aggregates created by harsh mechanical stress showed the largest number of subvisible particles, and the class generated by thermal stress displayed the largest number of visible particles. Most classes showed a disruption of the higher order structure, with the degree of disorder depending on the stress process. Particles in all classes (except thermal stress) were at least partially reversible upon dilution in pH 5 buffer. High copper content was detected in isolated metal-catalyzed aggregates, a stress previously shown to produce immunogenic aggregates. In conclusion, protein aggregates can be a very heterogeneous population, whose qualities are the result of the type of stress that was experienced.

Recommendation of Single Time Point Leachables Testing for Lyophilized Biotechnology Products Stored in Rubber Stoppered Glass Vial Systems.

As a popular format of primary container closure systems, rubber stoppered glass vials are often used in storing and delivering lyophilized and liquid formulated therapeutic protein products. Assessing extractables and leachables from rubber stoppered glass vial systems is required to ensure drug product quality and patient safety. Lyophilized biopharmaceutical drug products are generally considered as less impacted by leachables during storage and transportation than the liquid formulated drug products. Single time point leachables testing for lyophilized biopharmaceutic drug products is recommended. The recommendation is based on our published comprehensive leachable data collected at multiple time points for five lyophilized drug products stored in different rubber stoppered glass vial systems with additional supporting comprehensive leachable data collected for nineteen liquid formulated drug products stored in different syringe and vial systems, which is statistically and scientifically sound. The leachable data evaluated herein were generated based on a holistic approach which ensured successful qualification of different vial systems as primary containers and delivery systems for various biotherapeutic products. The organic and elemental impurities of the leachable profiles of all the twenty-four drug product samples were below the limit of detection at all the time points. For lyophilized drug products, product surface interaction during storage time and shipping is unlikely. Timing of single time point leachables testing can be flexible. Performing leachables testing at one-year time point is recommended as it allows for enough time for chemicals to leach out from product contact surfaces into drug products and thus provides the earliest opportunity for mitigation of unpredicted leachables of concern, if any. However, testing at other stability time points can also be considered depending on the development strategy of the sponsor. Therefore, recommendation of single time point leachables testing for lyophilized drug products stored in rubber stopped glass vials at an appropriate time point is a scientifically sound approach.

Observation and Mitigation of Lamellar Silica Particles Formed in Pharmaceutical Products Packaged in Glass Vials.

A new type of lamellae-like particles was observed in protein based liquid therapeutic protein drug product (DP) packaged in standard (STD) and delamination controlled (DC) Type IB glass vials stored at 2-8°C as early as two weeks after manufacture. These particles were determined to be remarkably different from lamellae in not only in their chemical composition, but in the mechanism by which these are formed. The lamellae-like particles were an ultra-thin (< 200 nm) film, appeared curled, sheet-like, folded with no defined edges identified as lamellar silica composed of silica and polysorbate 80 (PS 80). It was also observed that the lamellar silica particles, when formed in a given drug product lot, not only were observed in a small percentage of vials, but also remained at low (≤ 5) numbers in affected vials, often decreasing in number over time. This is in contrast to the large number of commonly reported glass lamellae (hundreds per vial) observed in vials prone to delamination with a glass vial interior showing a delaminated inner surface. In this case study, evidence from low Si leachable levels in solution and various surface analytical techniques supported the conclusion that there was neither delamination nor early signs of glass delamination like reaction zones occurring in those impacted vials, regardless. A mechanism for particle formation was hypothesized and experimentally confirmed. Lamellar silica particles are composed of an admixture of condensed silica and PS 80 deposited on the interior walls of glass vials, which form and may be released into solution over time. The root cause was determined to be conditions present during preparation of the vials for drug product filling, specifically the vial washing and depyrogenation steps. These conditions are known to make glass vials prone to delamination; in this case study, they resulted in interactions between the glass and PS 80 present in the formulation. Incomplete drying of the glass vials during depyrogenation in closed ovens was confirmed as the contributing factors that led to lamellar silica particle formation via the studies of silicate spiked into the DC Type IB glass vials filled with the mAb DP in which lamellar silica particles were observed. Prevention of lamellar silica particles formation was successfully achieved through optimization of the duration and pressure of air blow during the vial washing and drying process in a depyrogenation oven. This was evidenced by the lack of appearance of the lamellar silica particles over 48 months for the DP lots filled post optimization. Additionally, the formation of lamellar silica was also mitigated by changing the vial washing process from a closed oven process to a tunnel process, which allowed for improved air flow and hence better drying of the vial primary container.

A Holistic Approach of Extractables and Leachables Assessment of Rubber Stoppered Glass Vial Systems for Biotechnology Products.

Rubber stoppered glass vial systems are widely used as primary containers for storing and delivering therapeutic protein products to patients. Addressing concerns and regulatory expectations related to the risk to biologic drug product quality and patient safety from rubber stoppered glass vial systems requires implementation of an extractable and leachable evaluation program based on material understanding, risk assessment, literature review, and a comprehensive scientifically sound analytical testing methodology. The extractable and leachable study design consisted of twelve drug products filled in twelve different size glass vials capped with laminated and nonlaminated rubber stoppers made from three different rubber formulations. Design of the model solvents was successful as they had little to no analytical interference and mimicked the formulation conditions and generated representative extractables capable of predicting leachables. The extraction conditions of time and temperature were appropriate as not to degrade the test materials or the extractable compounds, and yet generated significant quantities for identification of the extractable compounds with confidence. The extractables testing results were capable of predicting the leachable profiles of the twelve drug products. In each case, the leachable profile was a subset of the extractable profile. The organic and elemental impurities of the leachable profiles of drug products were the end-to-end verification of the quality of the glass vials, rubber stoppers and drug product lifecycles. Overall, the holistic approach was fully successful in the qualification of different vial systems as primary containers and delivery systems for different biotherapeutic products to ensure product quality and patient safety.

Observation and Mitigation of Leachables from Non-Product Contact Materials in Electromechanical Delivery Devices for Biotechnology Products.

Battery-powered drug delivery devices are widely used as primary containers for storing and delivering therapeutic protein products to improve patient compliance and quality of life. Compared to conventional delivery approaches such as pre-filled syringes, battery-powered devices are more complex in design requiring new materials/components for proper functionality, which could cause potential product safety and quality concerns from the extractable and leachables (E&L) of the new materials/components. In this study, E&L assessments were performed on a battery-powered delivery device during the development and qualification of the device, where novel compound 2­hydroxy-2-methylpropiophenone (HMPP) and related compounds were observed in both E&L. The source of the HMPP and related compounds was identified to be the nonproduct contact device batteries, in which HMPP photo-initiator was used as a curing agent in the battery sealant to prevent leakage of the battery electrolytes. Toxicology assessment was performed, which showed the levels of HMPP observed in the device lots were acceptable relative to the permitted daily exposure. A drug product HMPP spike study was also performed, where no product impact was observed. Based on these assessments, an action threshold and specification limits could be established as a control strategy, if needed, to mitigate the potential risks associate with the observed leachables. As a full resolution, seven battery candidates from different suppliers were screened and one new battery was successfully qualified for the delivery devices. Overall, the holistic E&L approach was fully successful in the development and qualification of the battery-powered devices for biotherapeutic products delivery ensuring product quality and patient safety. Non-product contact materials are commonly rated as low or no risk and typically considered as out of scope of E&L activities for delivery systems following industry benchmark and regulatory agency guidance. This case study is novel as it brings into attention the materials that might not normally be in consideration during the development process. It is highly recommended to understand materials in the context of intended use on a case-by-case basis and not to generalize to ensure successful development and qualification.

A Risk-Based Approach to Evaluate and Control Elemental Impurities in Therapeutic Proteins.

Control of elemental impurities in the drug products evolved from the generic visual testing of heavy metals as their sulfides to specific elements of toxicological concern in the final drug products by instrumental analysis. The International Council for Harmonisation (ICH) Q3D (R1) guideline for elemental impurities describes a risk-based approach to identify, assess, and control the potential elemental impurities in drug products within the established permitted daily exposures (PDE). Challenges to this approach include how to assess the risks associated with contributing sources such as utilities, manufacturing equipment, container-closure systems, and excipients. Defining at what stage of development that such assessment should be performed to identify the risk levels can be equally challenging. In this article, we report an approach to control elemental impurities of toxicological concern, compliant to the Q3D (R1) guideline, and a summary of results obtained on multiple protein therapeutic products. This approach follows the elements of Process Validation, i.e., Design, Qualification, and Continuous Verification. The design includes the selection of excipients and their suppliers that meet the Option 1 requirement of Q3D (R1). It also comprises the selection of manufacturing equipment, container-closure systems, and utilities. The qualification includes the testing of the potential sources of elemental impurities, i.e., excipients, utilities, and leachables/extractables from the manufacturing equipment and container-closure systems. The Continuous Verification comes from the testing of representative batches at the initiation of stability studies of clinical or commercial drug product batches and at the end of shelf-life expiry of the drug product, and when changes are made to the manufacturing equipment, sources of excipients and container closure systems, and any formulation changes. Our experience shows that the risk associated with the impurity levels of the ten elements of toxicological concern in the therapeutic protein drug products, parenterally administered, is well below the control threshold (30% PDE) in the drug product recommended by the ICH Guideline. Although our focus is on the injectable therapeutic proteins, this approach can be applied to the products administered via other routes as well.

Holistic Extractables and Leachables Program: Evaluations of Prefilled Syringe Systems for Biotechnology Products.

Prefilled syringes (PFS) are a container and delivery device of choice for storing and administering therapeutic protein products to patients. Addressing concerns and regulatory expectations related to the risk to biologic drug product quality and patient safety from PFS requires implementation of an extractable and leachable program based on understanding of materials, risk assessment, review of existing literature, and testing supported by a sound scientific foundation. Extractables and leachables data generated as part of a thorough and holistic program are presented for five PFS systems, including glass and plastic syringes filled with 12 biologic drug products encompassing the implementation of traditional and single-use biotechnology manufacturing processes. The comprehensive extractables and leachables data presented demonstrate and substantiate a holistic extractable and leachable program designed to ensure product quality and patient safety.

An Evaluation of the Glass Vial Hydrolytic Resistance Method.

The European Pharmacopoeia (Ph. Eur.) hydrolytic resistance method for glass vials is routinely used to screen pharmaceutical glass vial supply. In an effort to better understand and control the factors affecting method precision and robustness, several potential sources of variability in the Ph. Eur. alkalinity method have been studied for 3 cc glass vials. Method parameters including vial rinsing, vial covering, autoclave cycle execution, sample hold times, and titration procedure were evaluated in this study. The results of this study indicate the method parameters which require stringent control in order to achieve acceptable method precision and robustness.LAY ABSTRACT: The European Pharmacopoeia (Ph. Eur.) hydrolytic resistance method for glass vials is routinely used to screen biopharmaceutical glass vial supply. The method was studied to assess contributions to its variability and to potentially improve its reliability. The results of this study indicate which method parameters require stringent control in order to generate reliable data using the Ph. Eur. hydrolytic resistance method.

Determination of interactions between antibody biotherapeutics and copper by size exclusion chromatography (SEC) coupled with inductively coupled plasma mass spectrometry (ICP/MS).

The concept of coupling of size-exclusion HPLC with ICP/MS (SEC-ICP/MS) was first applied in this work as a novel approach in the biotechnology field to assess metal binding to Immunoglobulin G (IgG) mAbs. This method can be used to probe the mechanism and biophysical properties of metal-protein interactions to gain a deeper understanding of the potential impact of metals during drug product manufacturing. Two IgG1s and one IgG2 drugs were investigated. Cu2+ was selected as the metal of interest due to its known ability to form strong complexes with organic molecules and to bind and enhance the degradation of mAbs. Instrument and separation conditions (interface, columns, and mobile phase) were studied for the separation of the protein-metal bound and unbound fractions of a bovine superoxide dismutase (SOD) standard prior to on-line detection of the mAb-metal (Cu) binding. The SEC-ICP/MS method was used to show copper binding by biotherapeutics by comparing the retention times of the protein by SEC and the metal by ICP/MS, to see if they co-elute at the same time. The approach developed offers considerable advantages over methods based on ultrafiltration followed by off-line metal determination in terms of speed, simplicity, precision and selectivity regarding the molecular weight of the complexes involved. In conjunction with other techniques, this method may provide in-depth knowledge of metal-induced mAb degradation mechanisms in biologics process development, be used as an analytical tool for mAb manufacturing in the cell culture process, and be applied during various stages of drug product manufacturing to gain a deeper understanding of the potential impact of metals during biotherapeutic development.

Development of Conductivity Method as an Alternative to Titration for Hydrolytic Resistance Testing Used for Evaluation of Glass Vials Used in Pharmaceutical Industry.

The European Pharmacopeia surface test to analyze the hydrolytic resistance is a common industrial method to understand and ensure the quality of produced glass vials. Hydrolytic resistance is evaluated by calculating the alkalinity of water extract from autoclaved vials by titration. As an alternative to this titration technique, a conductivity technique was assessed, which directly measures the ions in the water extract. A conductivity meter with a 12 mm diameter electrode was calibrated with a 100 µS/cm conductivity standard and carryover minimized by rinsing the probe in a water beaker per analysis. The limit of quantification at 1 µS/cm was determined as having a signal-to-noise ratio of 3 compared with the water blank. The conductivity method was selective for glass-composing elements (boron, sodium, aluminum, silicon, potassium, and calcium) within the vial extract. Accuracies of spiked conductivity standard within the range of 1 to 100 µS/cm were ±7% and had linearity with coefficient of determination (R2) of ≥0.9999. Intraday precision had a relative standard deviation (RSD) (n = 5) of ≤6% for spiked conductivity standard within the range of 1 to 100 µS/cm. Interday precision had a RSD (n = 4) of ≤6% for 10 vials from three glass vial lots. Conductivity of water extracts from nine sets of seven lots of glass vials had a precise linear relationship [R2 = 0.9876, RSD = 1% (n = 9)] with titration volumes of the same lots. Conductivity results in µS/cm could be converted to titration volumes in milliliters by a conversion factor of 0.0275. The simplicity, sample stability, and individual vial analysis of the conductivity technique were more advantageous than the current titration technique. LAY ABSTRACT: The quality of glass vials used as primary containers in the pharmaceutical industry is of concern due to recent observations of glass flake-like delamination, or lamellae, under specific storage conditions. The current European Pharmacopoeia method to assess glass vial quality utilizes acid titration of vial extract pools to determine hydrolytic resistance or alkalinity. As an alternative to the European Pharmacopoeia method, the vial extracts were analyzed for conductivity, which directly determines the level of ions that were readily extracted from the vial surfaces. Lower quality glass would have greater surface defects that lead to higher ions extracted and higher conductivity value. The conductivity method was found to be suitable to measure the ions in water extracts and showed strong correlation with alkalinity. The advantage of the conductivity method over the alkalinity method was greater ease, lower volume requirements, stability, and flexibility in analysis.

Characterization of Protein Aggregating Tungstates: Electrospray Mass Spectrometry Analysis of Extracts from Prefilled Syringes and from Tungsten Pins Used in the Manufacture of Syringes.

UNLABELLED: Glass prefilled syringes are increasingly becoming a container of choice for storing and administering therapeutic protein products to patients. Tungsten leaching from a PFS is known to induce protein particle formation, and the source was traced to the tungsten pins used in the manufacturing process of the syringe barrels. Study of the tungstates present in extracts from both tungsten pins used in the syringe manufacturing process and from single syringes from various suppliers was undertaken. Electrospray mass spectrometry was chosen as a technique with the sensitivity to characterize tungstates at levels (∼1 ppm of elemental tungsten) observed in single syringes. Extraction solvents were chosen to simulate the range (pH 4.0-7.0) typically used for therapeutic protein formulation. A commercial product formulation buffer was also used as an extraction solution to characterize tungstate species used for tungsten spiking studies of protein. All pin and syringe extracts from various manufacturers were similar in regards to containing stable Na/K containing lacunary polytungstate ([W11O39](7-)) species, which were the main species present in syringe extracts and are different than the metatungstate ([W12O39](6-)) species identified in commercially available sodium polytungstate and as the main species in pin extracts. These stable Na/K containing polytungstates species present in pin and syringe extracts are likely formed during the glass manufacturing process at >400 °C and may have the capability to subsequently form larger polytungstate complexes. LAY ABSTRACT: Glass prefilled syringes are a type of container used for storing and administering biotechnology medicines to patients. The manufacturing process for the syringes may lead to very low levels of the metal tungsten being present in the syringes, and thus in the medicine stored in the syringes. The presence of tungsten in certain biotechnology medicines has been shown to cause changes to the medicine. Understanding something that can cause a medicine to change is an important part of producing safe and effective medicines for patients. The study described in this article sought to increase understanding by characterizing the form of tungsten observed in syringes from a number of vendors. Study of the tungsten present in syringes from four vendors indicates the same form of tungsten is observed regardless of the vendor. The study also found that the form of tungsten differed from that expected.

Comparison of Acid Titration, Conductivity, Flame Photometry, ICP-MS, and Accelerated Lamellae Formation Techniques in Determining Glass Vial Quality.

Certain types of glass vials used as primary containers for liquid formulations of biopharmaceutical drug products have been observed with delamination that produced small glass like flakes termed lamellae under certain conditions during storage. The cause of this delamination is in part related to the glass surface defects, which renders the vials susceptible to flaking, and lamellae are formed during the high-temperature melting and annealing used for vial fabrication and shaping. The current European Pharmacopoeia method to assess glass vial quality utilizes acid titration of vial extract pools to determine hydrolytic resistance or alkalinity. Four alternative techniques with improved throughput, convenience, and/or comprehension were examined by subjecting seven lots of vials to analysis by all techniques. The first three new techniques of conductivity, flame photometry, and inductively coupled plasma mass spectrometry measured the same sample pools as acid titration. All three showed good correlation with alkalinity: conductivity (R(2) = 0.9951), flame photometry sodium (R(2) = 0.9895), and several elements by inductively coupled plasma mass spectrometry [(sodium (R(2) = 0.9869), boron (R(2) = 0.9796), silicon (R(2) = 0.9426), total (R(2) = 0.9639)]. The fourth technique processed the vials under conditions that promote delamination, termed accelerated lamellae formation, and then inspected those vials visually for lamellae. The visual inspection results without the lot with different processing condition correlated well with alkalinity (R(2) = 0.9474). Due to vial processing differences affecting alkalinity measurements and delamination propensity differently, the ratio of silicon and sodium measurements from inductively coupled plasma mass spectrometry was the most informative technique to assess overall vial quality and vial propensity for lamellae formation. The other techniques of conductivity, flame photometry, and accelerated lamellae formation condition may still be suitable for routine screening of vial lots produced under consistent processes. LAY ABSTRACT: Recently, delamination that produced small glass like flakes termed lamellae has been observed in glass vials that are commonly used as primary containers for pharmaceutical drug products under certain conditions during storage. The main cause of these lamellae was the quality of the glass itself related to the manufacturing process. Current European Pharmacopoeia method to assess glass vial quality utilizes acid titration of vial extract pools to determine hydrolytic resistance or alkalinity. As alternative to the European Pharmacopoeia method, four other techniques were assessed. Three new techniques of conductivity, flame photometry, and inductively coupled plasma mass spectrometry measured the vial extract pool as acid titration to quantify quality, and they demonstrated good correlation with original alkalinity. The fourth technique processed the vials under conditions that promote delamination, termed accelerated lamellae formation, and the vials were then inspected visually for lamellae. The accelerated lamellae formation technique also showed good correlation with alkalinity. Of the new four techniques, inductively coupled plasma mass spectrometry was the most informative technique to assess overall vial quality even with differences in processing between vial lots. Other three techniques were still suitable for routine screening of vial lots produced under consistent processes.

Creating a Holistic Extractables and Leachables (E&L) Program for Biotechnology Products.

UNLABELLED: The risk mitigation of extractables and leachables presents significant challenges to regulators and drug manufacturers with respect to the development, as well as the lifecycle management, of drug products. A holistic program is proposed, using a science- and risk-based strategy for testing extractables and leachables from primary containers, drug delivery devices, and single-use systems for the manufacture of biotechnology products. The strategy adopts the principles and concepts from ICH Q9 and ICH Q8(R2). The strategy is phase-appropriate, progressing from extractables testing for material screening/selection/qualification through leachables testing of final products. The strategy is designed primarily to ensure patient safety and product quality of biotechnology products. The holistic program requires robust extraction studies using model solvents, with careful consideration of solvation effect, pH, ionic strength, temperature, and product-contact surface and duration. From a wide variety of process- and product-contact materials, such extraction studies have identified and quantified over 200 organic extractable compounds. The most commonly observed compounds were siloxanes, fatty acid amides, and methacrylates. Toxicology assessments were conducted on these compounds using risk-based decision analysis. Parenteral permitted daily exposure limits were derived, as appropriate, for the majority of these compounds. Analysis of the derived parenteral permitted daily exposure limits helped to establish action thresholds to target high-risk leachables in drug products on stability until expiry. Action thresholds serve to trigger quality investigations to determine potential product impact. The holistic program also evaluates the potential risk for immunogenicity. This approach for primary drug containers and delivery devices is also applicable to single-use systems when justified with a historical knowledge base and understanding of the manufacturing processes of biotechnology products. LAY ABSTRACT: In the development of a drug product, careful consideration is given to impurities that may originate from manufacturing equipment, process components, and packaging materials. The majority of such impurities are common chemical additives used to improve the physicochemical properties of a wide range of plastic materials. Suppliers and drug manufacturers conduct studies to extract chemical additives from the plastic materials in order to screen and predict those that may leach into a drug product. In this context, the term extractables refers to a profile of extracted compounds observed in studies under harsh conditions. In contrast, the term leachables refers to those impurities that leach from the materials under real-use conditions and may be present in final drug products. The purpose of this article is to present a holistic approach that effectively minimizes the risk of leachables to patient safety and product quality.

Extractables analysis of single-use flexible plastic biocontainers.

UNLABELLED: Studies of the extractable profiles of bioprocessing components have become an integral part of drug development efforts to minimize possible compromise in process performance, decrease in drug product quality, and potential safety risk to patients due to the possibility of small molecules leaching out from the components. In this study, an effective extraction solvent system was developed to evaluate the organic extractable profiles of single-use bioprocess equipment, which has been gaining increasing popularity in the biopharmaceutical industry because of the many advantages over the traditional stainless steel-based bioreactors and other fluid mixing and storage vessels. The chosen extraction conditions were intended to represent aggressive conditions relative to the application of single-use bags in biopharmaceutical manufacture, in which aqueous based systems are largely utilized. Those extraction conditions, along with a non-targeted analytical strategy, allowed for the generation and identification of an array of extractable compounds; a total of 53 organic compounds were identified from four types of commercially available single-use bags, the majority of which are degradation products of polymer additives. The success of this overall extractables analysis strategy was reflected partially by the effectiveness in the extraction and identification of a compound that was later found to be highly detrimental to mammalian cell growth. LAY ABSTRACT: The usage of single-use bioreactors has been increasing in biopharmaceutical industry because of the appealing advantages that it promises regarding to the cleaning, sterilization, operational flexibility, and so on, during manufacturing of biologics. However, compared to its conventional counterparts based mainly on stainless steel, single-use bioreactors are more susceptible to potential problems associated with compound leaching into the bioprocessing fluid. As a result, extractable profiling of the single-use system has become essential in the qualification of such systems for its use in drug manufacturing. The aim of this study is to evaluate the effectiveness of an extraction solvent system developed to study the extraction profile of single-use bioreactors in which aqueous-based systems are largely used. The results showed that with a non-targeted analytical approach, the extraction solvent allowed the generation and identification of an array of extractable compounds from four commercially available single-use bioreactors. Most of extractables are degradation products of polymer additives, among which was a compound that was later found to be highly detrimental to mammalian cell growth.

A cytotoxic leachable compound from single-use bioprocess equipment that causes poor cell growth performance.

A current trend in the production of biopharmaceuticals is the replacement of fixed stainless steel fluid-handling units with disposable plastic bags. Such single-use systems (SUS) offer numerous advantages, but also introduce a new set of materials into the production process and consequently expose biomanufacturers to a new set of risks related to those materials, not to mention reliance on an entirely new supply chain. In the course of developing and conducting a cell-growth-based test for suitability of disposable plastic components destined for use in cell culture operations, we discovered that the cytotoxic compound bis(2,4-di-tert-butylphenyl)phosphate (bDtBPP) leaches out of certain bags and into cell culture media in concentrations that are deleterious to cell growth. Specifically, media held in certain bags for several days at 37°C was found to contain bDtBPP, and use of those held-media samples in cell growth experiments provides data that overlap neatly with cell growth experiments using media spiked directly with bDtBPP, proving that bDtBPP leaching is responsible for the reduced growth attributable to those SUS bags. Overall, this issue represents a risk to the production of biopharmaceuticals in SUS, a risk that must be managed by diligent collaboration among companies along the entire supply chain for SUS components.