Particle contamination of parenteralia and in-line filtration of proteinaceous drugs

Impact of tubing material on stability and filling accuracy of biologic drug product

This article is presenting completely new observations linked to Polysorbate 80 (PS80) oxidation in biologics drug product. Indeed, we observed that, in the drug product exposed to long contact time (∼ 1 h) in platinum-cured silicon tubing during the filling, the oxidation of PS80 is dramatically accelerated compared to short contact time. The phenomenon was observed in presence of iron traces (20 ppb), but not in absence of iron (< 2 ppb) or in presence of a chelator like EDTA. Electron Paramagnetic Resonance (EPR) measurements demonstrated the presence of radicals formed during the oxidation. It was deduced that platinum-cured silicon tubing is leaching some radical initiators, most probably peroxides decomposed by the iron. Alternative filling sets made of ThermoPlastic Elastomer (TPE) were investigated, both for the impact on PS80 stability and the filling performance using a peristaltic pump. The results showed that these filling sets were indeed not causing accelerated PS80 degradation but the process was not robust enough; these filling sets being too rigid for the constraints of the peristaltic pump rollers. These results show that there is no practical tubing alternative to platinum silicone cured tubing. To avoid the impact on PS80 oxidation the potential remediations presented in the article are to avoid any trace of iron or to add a chelating agent, or to discard the vials having experimented a filling stop (> 5 min).

A Survey on Handling and Administration of Therapeutic Protein Products in German and Swiss Hospitals

Protein products in hospitals often have to be compounded before administration to the patient. This may comprise reconstitution of lyophilizates, dilution, storage, and transport. However, the operations for compounding and administration in the hospital may lead to changes in product quality and possibly even impact patient safety. We surveyed healthcare practitioners from three clinical units using a questionnaire and open dialogue to document common procedures and their justification and to document differences in handling procedures. The survey covered dose compounding, transportation, storage and administration. One key observation was that drug vial optimization procedures were used for some products, e.g., use of one single-use vial for several patients. This included the use of spikes and needles or closed system transfer devices (CSTDs). Filters or light protection aids were used only when specified by the manufacturer. A further observation was a different handling of the overfill in pre-filled infusion containers, possibly impacting total dose. Lastly, we documented the complexity of infusion administration setups for administration of multiple drugs. In this case, flushing procedures or the placement and use of filters in the setup vary. Our study has revealed important differences in handling and administration practice. We propose that drug developers and hospitals should collaborate to establish unified handling procedures.

Characterization of Silicone from Closed System Transfer Devices and its Migration into Pharmaceutical Drug Products

Closed System Transfer Devices (CSTDs) are increasingly used in healthcare settings to facilitate compounding of hazardous drugs but increasingly also therapeutic proteins. However, their use may significantly impact the quality of the sterile product. For example, contamination of the product solution may occur by leaching of silicone or particulates from the CSTDs. It was therefore the aim of the present study to identify and quantify the types of silicone oil in a panel of typically used CSTDs. Particles found after simulated CSTD compounding processes were evaluated using Light Obscuration and Micro-Flow Imaging and were confirmed to be silicone oil particles. The number of particulates shed from CTSDs was in single cases exceeding pharmacopeial limits for a final parenteral product. Using X-ray microtomography, lubrication was shown to be primarily applied at connecting parts of the CSTD. Quantitative and qualitative analysis by Fourier transform infrared spectroscopy (FTIR) revealed a total released amount between 0.8 and 16 mg per CSTD of polydimethylsiloxane or polymethyltrifluoropropylsiloxane per CSTD. While pronounced differences in total silicone content between CSTDs were observed, it did not fully correlate with particle contamination in the test solutions, potentially due to variations in CSTD design. The impact of typical surfactants in biological formulations on silicone migration into product was additionally evaluated. We conclude that CSTDs may compromise final product quality, as (different types of) silicone oil may be released from these devices and contaminate the administered product.

Shear stress as a driver of degradation for protein-based therapeutics: More accomplice than culprit

Protein degradation is a major concern for protein-based therapeutics. It may alter the biological activity of the product and raise the potential for undesirable effects on the patients. Among the numerous drivers of protein degradation, shear stress has been the focus around which much work has revolved since the 1970s. In the pharmaceutical realm, the product is often processed through several unit operations, which include mixing, pumping, filtration, filling, and atomization. Nonetheless, the drug might be exposed to significant shear stresses, which might cooperatively contribute to product degradation, together with interfacial stress. This review presents fundamentals of shear stress about protein structure, followed by an overview of the drivers of product degradation. The impact of shear stress on protein stability in different unit operations is then presented, and recommendations for limiting the adverse effects on the biopharmaceutical formulations are outlined. Finally, several devices used to explore the effects of shear stress are discussed.

Comparative study between a gravity-based and peristaltic pump for intravenous infusion with respect to generation of proteinaceous microparticles

Subvisible particles generated during the preparation or administration of biopharmaceuticals might increase the risk of immunogenicity, inflammation, or organ dysfunction. To investigate the impact of an infusion system on the level of subvisible particles, we compared two types of infusion set based on peristaltic movement (Medifusion DI-2000 pump) and a gravity-based infusion system (Accu-Drip) using intravenous immunoglobulin (IVIG) as a model drug. The peristaltic pump was found to be more susceptible to particle generation compared to the gravity infusion set owing to the stress generated due to constant peristaltic motion. Moreover, the 5-µm in-line filter integrated into the tubing of the gravity-based infusion set further contributed to the reduction of particles mostly in the range ≥ 10 µm. Furthermore, the filter was also able to maintain the particle level even after the pre-exposure of samples to silicone oil lubricated syringes, drop shock, or agitation. Overall, this study suggests the need for the selection of an appropriate infusion set equipped with an in-line filter based on the sensitivity of the product.

Enhanced protein aggregation suppressor activity of N-acetyl-l-arginine for agitation-induced aggregation with silicone oil and its impact on innate immune responses

Previously, N-acetyl-l-arginine (NALA) suppressed the aggregation of intravenous immunoglobulins (IVIG) more effectively and with a minimum decrease in transition temperature (T_m) than arginine monohydrochloride. In this study, we performed a comparative study with etanercept (commercial product: Enbrel®), where 25 mM arginine monohydrochloride (arginine) was added to the prefilled syringe. The biophysical properties were investigated using differential scanning calorimetry (DSC), dynamic light scattering (DLS), size-exclusion chromatography (SEC), and flow-imaging microscopy (FI). NALA retained the transition temperature of etanercept better than arginine, where arginine significantly reduced the T_m by increasing its concentration. End-over-end rotation was applied to each formulation for 5 days to accelerate protein aggregation and subvisible particle formation. Higher monomeric content was retained with NALA with a decrease in particle level. Higher aggregation onset temperature (T_agg) was detected for etanercept with NALA than arginine. The results of this comparative study were consistent with previous study, suggesting that NALA could be a better excipient for liquid protein formulations. Agitated IVIG and etanercept were injected into C57BL/6 J female mice to observe immunogenic response after 24 h. In the presence of silicone oil, NALA dramatically reduced IL-1 expression, implying that decreased aggregation was related to reduced immunogenicity of both etanercept and IVIG.

An Industry Perspective on Compatibility Assessment of Closed System Drug-Transfer Devices for Biologics

The Formulation Workstream of the BioPhorum Development Group (BPDG), an industry-wide consortium, has identified the increased use of closed system drug-transfer devices (CSTDs) with biologics, without an associated compatibility assessment, to be of significant concern. The use of CSTDs has increased significantly in recent years due to the recommendations by NIOSH and USP that they be used during preparation and administration of hazardous drugs. While CSTDs are valuable in the healthcare setting to reduce occupational exposure to hazardous compounds, these devices may present particular risks that must be adequately assessed prior to use to ensure their compatibility with specific types of drug products, such as biologic drugs, which may be sensitive. The responsibility of ensuring quality of biologic products through preparation and administration to the patient lies with the drug product sponsor. Due to the significant number of marketed CSTD systems, and the large variety of components offered for each system, a strategic, risk-based approach to assessing compatibility is recommended herein. In addition to traditional material compatibility, assessment of CSTD compatibility with biologics should consider additional parameters to address specific CSTD-related risks. The BPDG Formulation Workstream has proposed a systematic risk-based evaluation approach as well as a mitigation strategy for establishing suitability of CSTDs for use.

Test models for the evaluation of immunogenicity of protein aggregates

Protein aggregates have been discussed for a long time as a potential risk factor for immunogenicity in patients. Meanwhile, many research groups have investigated the immunogenicity of differently produced aggregates using in vitro or in vivo models. Despite all knowledge gained in these studies still little is known about the mechanisms of immunogenicity and the kind of protein aggregates bearing the greatest risk for immunogenicity. The choice of a suitable test model regarding the predictability of immunogenicity of protein aggregates in humans plays a major role and influences results and conclusions substantially. In this review we will provide an overview of the test models recently used for the evaluation of immunogenicity of protein aggregates; we will discuss advantages and drawbacks regarding their usability and predictive power for immunogenicity in humans.

Expanding Bedside Filtration-A Powerful Tool to Protect Patients From Protein Aggregates

Protein immunogenicity is intensively researched by academics, biopharmaceutical companies, and authorities as it can compromise the safety and efficacy of a biopharmaceutical drug. So far, the exact protein aggregate properties inducing immune responses are not known. Possible protein-related factors could be size, chemical modifications, or higher order structures. It is impossible to achieve an absolute absence of protein aggregates even for very stable formulations. The application of "bedside filtration," meaning filtration during the preparation or administration of the drug product immediately before injection, has the potential to increase the safety of every drug container and could prevent the undesired injection of particulate matter into the patient. In this study, the high efficiency of filtration for reducing the amount of protein particles was demonstrated with more than 19 stressed and nonstressed biopharmaceutical products which covered a broad concentration and molecular weight range. Furthermore, critical aspects regarding the usage of filters such as particle shedding from filters, protein loss as a result of protein adsorption, or the hold-up volume of the filters were assessed. Although differences between the filters were observed, no negative impact by the investigated filters could be found. A broader application of bedside filtration is therefore proposed.

Microparticles and Nanoparticles Delivered in Intravenous Saline and in an Intravenous Solution of a Therapeutic Antibody Product

Intravenous (IV) infusion is used for administration of a large proportion of biologic therapeutics, including most monoclonal antibody products. In this study, we determined the subvisible particle levels in IV solutions and after the solutions were processed with an IV administration setup that mimicked the typical clinical method of administration. IV saline in bags manufactured by both Hospira and Baxter contained 1600-8000 microparticles/mL and 4-73 × 10⁶ nanoparticles/mL in solution. When IV immunoglobulin was diluted into the IV saline, 3700-23,000 microparticles/mL and 18-240 × 10⁶ nanoparticles/mL were detected. During processing of the solution through the IV system, in-line filters removed most microparticles. However, there were still 1-21 × 10⁶ nanoparticles/mL in IV saline and 7-83 × 10⁶ nanoparticles/mL in IV immunoglobulin diluted in saline. Finally, in samples processed through in-line filters, we found relatively large microparticles (20-60 μm) that were composed of protein or polycarbonate. These particles resulted from shedding of polycarbonate and sloughing off of protein films downstream from the filter membrane. Overall, the results document that even with in-line filters in place, high levels of subvisible particles are delivered to patients and there is a need for improved, more effective filters and IV solutions with lower particle levels.

Particulate Matter in Injectable Drugs: Evaluation of Risks to Patients

One of the fundamental principles guiding the pharmaceutical quality of parenteral products is to prevent injecting contaminants from microbiological, chemical or physical sources. It is just as difficult to ensure the absence of chemical and particulate contaminants in injectable products as it is to weigh up the microbiological risk. The problem of particulate matter is mainly related to the preparing and administrating of injectable drugs rather than through the contamination of marketed products. Particulate contamination also arises