Consistent Manufacturing Process Research Articles

Carbon Monoxide-Resistant Anode Catalysts for Single-Cell Direct Carbon Monoxide Fuel Cells: Binary, Ternary, And Quaternary Platinum Alloys as Anode Electrocatalysts

The objective of this paper is to present the results of experimentations on the custom-made anode electrocatalysts for direct carbon monoxide fuel cells (DCMFCs) inspired by catalysts commonly used for direct alcohol fuel cells. Seven different catalysts were fabricated and tested. The uniform and consistent manufacturing process and the test procedure allowed a meaningful comparison of the developed fuel cells. The results indicated that homemade Pt-Ru membrane-electrode assembly (MEA) could not compete with the Pt-Sn MEA. While the performance of the MEAs with Pt-Ru-Ni, Pt-Ru-Sn-Ni, and Pt-Ru-Sn-Co was not satisfactory, the Pt-Ru-Sn-Co-W MEA achieved the best performance among all MEAs with Nafion® 117 membrane. The last MEA was made of the Pt-Sn anode catalyst and Nafion® 212 membrane and outperformed all other MEAs by a wide margin. The experiments demonstrated that the performance of the best-developed MEA was three times better than the performance of the commercial Pt-Ru MEA. This means the performance of DCMFCs can be significantly improved by developing a suitable anode electrocatalyst, using a thinner membrane, and operating at optimum conditions. These results are not only applicable for DCMFCs but also are very useful for other proton exchange membrane fuel cells (PEMFCs) operating with CO-containing fuels.

GMP Compliant Production of a Cryopreserved Adipose-Derived Stromal Cell Product for Feasible and Allogeneic Clinical Use.

The emerging field of advanced therapy medicinal products (ATMP) holds promise of treating a variety of diseases. Adipose-derived stromal cells (ASCs) are currently being marketed or tested as cell-based therapies in numerous clinical trials. To ensure safety and efficacy of treatments, high-quality products must be manufactured. A good manufacturing practice (GMP) compliant and consistent manufacturing process including validated quality control methods is critical. Product design and formulation are equally important to ensure clinical feasibility. Here, we present a GMP-compliant, xeno-free, and semiautomated manufacturing process and quality controls, used for large-scale production of a cryopreserved off-the-shelf ASC product and tested in several phase I and II allogeneic clinical applications.

The Next Generation of MS2A Resin: MS3

ABSTRACT MS2A was a reduced ketone resin and a preferred varnish for many painting conservators but ceased production in 2014. To remedy this, a new, more consistent manufacturing process has recently been developed and the next generation of resin designed with replicated chemistry is called MS3. Direct comparison between MS3 and MS2A is limited as no fresh samples of MS2A exist, so work presented here focuses primarily on the performance and characteristics of MS3 compared to literature reports of MS2A, and comparisons to older reference samples of MS2A. Refractive index, gloss, glass transition temperature, and molecular weight are presented. MS3 and comparative low molecular weight varnish resins were artificially aged and examined using FTIR and color measurements. Practical handling and performance were evaluated by varnishing two oil paintings. This study has shown that new MS3 resin demonstrates consistency with older samples of MS2A alongside improvements in keto-reduction, color, flow, and batch to batch consistency.

Cultivated Autologous Limbal Epithelial Cell Transplantation: New Frontier in the Treatment of Limbal Stem Cell Deficiency

Taking into consideration prior human experience with treating limbal stem cell deficiency (LSCD) with cultivated limbal epithelial cells (CLEC) from other countries, we have set a goal to optimize and standardize the techniques of CLEC preparation (called CALEC by our group) for the clinical trial in the United States. We performed an extensive literature review of all human trials, case series, and reports involving autologous cultivated limbal epithelial cell transplantation. Allogeneic cultivated limbal epithelial cell transplantations were reported only when combined with autologous studies. We also searched prior animal data aiding in detailing regulatory toxicology requirements. Between 1997 and 2020, the analysis of human trials revealed 21 studies on autologous grafts, and 13 studies analyzing both autologous grafts and allogeneic grafts. Of a total of 34 studies, 6 studies used good manufacturing process (GMP) facilities, and 11 studies had no animal-derived products or murine feeder layers, whereas only 1 study had both. Overall, the treatment with autologous CLEC grafts was 68.9% successful. In total there were 6 preclinical studies using rabbits, serving as surrogate studies to assess the safety and toxicity of cultivated limbal epithelial cells for human trials. Based on prior human experience, we further optimized the manufacturing conditions with GMP-grade and serum and animal-free reagents, and developed cell characterization assays for the CALEC product release. These data were used to develop a novel and consistent manufacturing process using only qualified and validated reagents for performing the first clinical trial on CALEC transplantation to treat LSCD in the United States.

Effects of glue-line thickness and manufacturing defects on the pull-out behavior of glued-in rods

Glued-in rods are offering to timber joints not only enhanced stiffness and high load capacity but also aesthetical appearance and good fire resistance. However, no consistent manufacturing process and quality control method is reported in the literature. It is necessary to estimate the effect of possible manufacturing defects on pull-out behavior of glued-in rods. This paper presents the experimental results on glued-in rods with two types of possible manufacturing defects on site: eccentric position of rod in hole and inclined setting of rod in hole. The effect of manufacturing defects was investigated on the samples with three different glue-line thicknesses. A finite element model considering the elastic behavior of materials with their measured elastic parameters and dimensions is proposed. It illustrates the evolution of the stress distribution in the connection zone and explains the observed brittle failure modes.

Host cell protein testing strategy for hepatitis B antigen in Hexavalent vaccine – Towards a general testing strategy for recombinant vaccines

BackgroundRecombinant proteins expressed in host cell systems may contain host cell proteins (HCP) as impurities. While there is no clear evidence of clinical adverse events attributable to HCP, HCP levels and profiles must be documented to meet regulatory requirements and to understand the consistency of the biological product and manufacturing process. We present a general strategy for HCP characterization applied to a recombinant protein antigen, Hepatitis B surface antigen (HBsAg) used in a multivalent vaccine. MethodsPolyclonal antisera raised against HCPs in process fractions from a mock preparation of the HBsAg yeast expression host, Hansenula polymorpha, were used to develop a quantitative sandwich ELISA to measure HCP content in batches of purified recombinant HBsAg. Batches were also subjected to SDS-PAGE and LC-MS/MS to identify detectable proteins. Batch consistency was further assessed by SDS-PAGE/densitometry purity analysis and by the ratio of specific HBsAg content (by ELISA) to total protein. ResultsUsing the quantitative HCP ELISA, the HCP content showed no discernable trend in multiple HBsAg batches manufactured over a 5-year period. All batches were ≥95% pure by SDS-PAGE/densitometry, with consistent HBsAg/total protein ratios. In addition to the expected HBsAg antigen protein, LC-MS/MS analysis of three HBsAg batches identified several yeast proteins, none of which are known to cause adverse reactions in humans. ConclusionsAnalysis of multiple HBsAg batches showed consistent HCP content and identification profiles, as well as product purity and specific antigen content, demonstrating consistent manufacturing process. Recombinant vaccines, unlike therapeutic products, are administered infrequently with only small amounts of protein injected at a time. With limited potential for adverse reactions to small quantities of HCPs in purified recombinant vaccine antigens, and considering the relevant regulatory guidelines, we conclude that once consistent manufacturing process has been demonstrated, routine HCP testing in recombinant vaccine antigens is no longer required.

Quantitative analysis of a biopharmaceutical protein in cell culture samples using automated capillary electrophoresis (CE) western blot

An effective control strategy is critical to ensure the safety, purity and potency of biopharmaceuticals. Appropriate analytical tools are needed to realize such goals by providing information on product quality at an early stage to help understanding and control of the manufacturing process. In this work, a fully automated, multi-capillary instrument is utilized for size-based separation and western blot analysis to provide an early readout on product quality in order to enable a more consistent manufacturing process. This approach aims at measuring two important qualities of a biopharmaceutical protein, titer and isoform distribution, in cell culture harvest samples. The acquired data for isoform distribution can then be used to predict the corresponding values of the final drug substance, and potentially provide information for remedy through timely adjustment of the downstream purification process, should the expected values fall out of the accepted range.

Toward a scalable and consistent manufacturing process for the production of human MSCs

The development of novel, affordable and efficacious therapeutics will be necessary to ensure the continued progression in the standard of global healthcare. With the potential to address previously unmet patient needs as well as tackling the social and economic effects of chronic and age-related conditions, cell therapies will lead the new generation of healthcare products set to improve health and wealth across the globe. However, if many of the small to medium enterprises (SMEs) engaged in much of the commercialization efforts are to successfully traverse the ‘Valley of Death’ as they progress through clinical trials, there are a number of challenges that must be overcome. No longer do the challenges remain biological but rather a series of engineering and manufacturing issues must also be considered and addressed.

Biosimilars: A consideration of the regulations in the United States and European union

Biosimilars are defined as biological products that are highly similar to a reference product, notwithstanding minor differences in clinically inactive components. Biosimilars show no clinically meaningful differences in safety, purity, and potency of the product in comparison to the reference product. With the ever looming patent expiry of some major high cost biologics, biosimilar production is becoming ever more lucrative to companies. Europe (EU) set the precedent, followed by the United States (US) in early 2012, for the approval process for biosimilars. Therefore, the purpose of this paper is to explore the nature of the regulatory processes in the US and EU and to determine the requirements of each in the approval process of a biosimilar. The current Food and Drug Administration (FDA) and European Medicines Agency's (EMA) guidance documents for biosimilars were reviewed revealing a need for further clarifications, as well as specifically addressing Celltrion's and Sandoz's application for approval for the biosimilars infliximab and filgrastim, respectively. Currently, the FDA and EMA focus on comparability in terms of the clinical, pharmacokinetic (PK)/pharmacodynamic (PD), preclinical, biological activity, and physiochemical characterization results, as well as requiring a robust and consistent manufacturing process. Both the EU and US have prepared guidance documents for biosimilars that will result in biotherapeutics that are as safe and efficacious as the innovator product but the necessity exists to globally harmonize international nonproprietary naming nomenclature and clarify how the concept of pharmacovigilance, extrapolation, and interchangeability will be handled and regulated in the future.

Effective multiple oral administration of reverse genetics engineered infectious bursal disease virus in mice in the presence of neutralizing antibodies.

Despite spectacular successes in hepatitis B and C therapies, severe hepatic impairment is still a major treatment problem. The clinically tested infectious bursal disease virus (IBDV) superinfection therapy promises an innovative, interferon-free solution to this great unmet need, provided that a consistent manufacturing process preventing mutations or reversions to virulent strains is obtained. To address safety concerns, a tissue culture adapted IBDV vaccine strain V903/78 was cloned into cDNA plasmids ensuring reproducible production of a reverse engineered virus R903/78. The therapeutic drug candidate was characterized by immunocytochemistry assay, virus particle determination and immunoblot analysis. The biodistribution and potential immunogenicity of the IBDV agent was determined in mice, which is not a natural host of this virus, by quantitative detection of IBDV RNA by a quantitative reverse transcriptase-polymerase chain reaction and virus neutralization test, respectively. Several human cell lines supported IBDV propagation in the absence of visible cytopathic effect. The virus was stable from pH 8 to pH 6 and demonstrated significant resistance to low pH and also proved to be highly resistant to high temperatures. No pathological effects were observed in mice. Single and multiple oral administration of IBDV elicited antibodies with neutralizing activities in vitro. Repeat oral administration of R903/78 was successful despite the presence of neutralizing antibodies. Single oral and intravenous administration indicated that IBDV does not replicate in mammalian liver alleviating some safety related concerns. These data supports the development of an orally delivered anti-hepatitis B virus/ anti-hepatitis C virus viral agent for human use.

Separation of rotavirus double-layered particles and triple-layered particles by capillary zone electrophoresis

Cell culture derived rotavirus preparations contain a mixture of double-layered particles (DLPs) and triple-layered particles (TLPs). Characterization of rotavirus vaccine products is important to demonstrate a consistent manufacturing process. A capillary zone electrophoresis (CZE) method was developed to separate and quantitate rotavirus DLPs and TLPs in cell lysate samples and CsCl-purified vaccine preparations of each of the five reassortant rotavirus vaccine strains (G1, G2, G3, G4 and P1) contained in the pentavalent rotavirus vaccine, RotaTeq®. The CZE electropherograms showed that migration of DLPs and TLPs from both CsCl-purified and cell lysates resulted in a separation distance of approximately 3min between the two rotavirus particle types. The identification of the peak(s) containing TLPs was confirmed for both CsCl-purified and cell lysate samples by treatment of the samples with 50mM EDTA, which converted TLPs to DLPs. The migration pattern of the DLPs was consistent (23–24min) among all reassortant strains tested, whether the DLPs were CsCl-purified or from cell lysates. However, the migration pattern of the TLP electropherograms of the reassortant rotavirus strains in cell lysates differed from those of the CsCl-purified reassortant rotavirus strains. In the cell lysate samples, the TLPs of the G1 and G2 reassortant rotavirus strains migrated slower that the corresponding TLPs from the CsCl-purified samples, while the migration time of the TLPs of the G3, G4 and P1 reassortants strains from the cell lysate and CsCl-purified samples appeared similar. Also, the TLPs from the CsCl-purified samples appeared as a defined single peak, while most of the TLPs from the cell lysate samples appeared as a broad peak or as multiple peaks. All the migration patterns were reproducible and consistent. Taking into account reproducibility, objective quantitation, and minimal sample manipulation as well as volume, CZE allowed consistent and quantitative characterization of rotavirus vaccine preparations, which is required for evaluation of vaccine products, including process validation.

FDA critical path initiatives: opportunities for generic drug development.

FDA's critical path initiative documents have focused on the challenges involved in the development of new drugs. Some of the focus areas identified apply equally to the production of generic drugs. However, there are scientific challenges unique to the development of generic drugs as well. In May 2007, FDA released a document "Critical Path Opportunities for Generic Drugs" that identified some of the specific challenges in the development of generic drugs. The key steps in generic product development are usually characterization of the reference product, design of a pharmaceutically equivalent and bioequivalent product, design of a consistent manufacturing process and conduct of the pivotal bioequivalence study. There are several areas of opportunity where scientific progress could accelerate the development and approval of generic products and expand the range of products for which generic versions are available, while maintaining high standards for quality, safety, and efficacy. These areas include the use of quality by design to develop bioequivalent products, more efficient bioequivalence methods for systemically acting drugs (expansion of BCS waivers, highly variable drugs), and development of new bioequivalence methods for locally acting drugs.