Pharmacokinetics of teduglutide in subjects with renal impairment.

PURPOSE: Teduglutide is a recombinant analogue of human glucagon-like peptide-2 that has recently been approved for the treatment of short bowel syndrome in adults. This study was designed to study the influence of renal function and age on teduglutide pharmacokinetics. METHODS: This was an open-label study with six parallel groups (6 subjects each). Three groups with renal impairment (moderate, severe and end-stage renal disease) were compared to healthy subjects with normal renal function, which were matched to the renal-impaired subjects with respect to demographics. At least two elderly subjects (≥65 years) were enrolled per group. A single dose of 10 mg teduglutide was subcutaneously administered to each subject. Teduglutide plasma concentrations were measured using a validated liquid chromatography method with tandem mass spectrometric detection, and the primary pharmacokinetic variables (AUCinf and Cmax) were calculated. RESULTS: Area under the concentration versus time curve extrapolated to infinity (AUCinf) and maximum plasma concentration (Cmax) of teduglutide in subjects with end-stage renal disease were approximately 2.59- and 2.08-fold higher, respectively, than those of healthy subjects. The AUCinf and Cmax were also slightly higher in subjects with moderate and severe renal impairment. Comparison of healthy subjects aged <65 years with healthy elderly subjects revealed very similar pharmacokinetics in both subgroups. CONCLUSIONS: In our study population, the primary pharmacokinetic parameters of teduglutide increased with increased severity of renal impairment. These results suggest that the daily dose of teduglutide should be reduced by 50 % in patients with moderate and severe renal impairment and end-stage disease. We found no effect of age on the pharmacokinetics of teduglutide in healthy subjects. The treatment was well tolerated, and there were no safety concerns.

Cellular elements for seeing in the dark: voltage-dependent conductances in cockroach photoreceptors.

BACKGROUND: The importance of voltage-dependent conductances in sensory information processing is well-established in insect photoreceptors. Here we present the characterization of electrical properties in photoreceptors of the cockroach (Periplaneta americana), a nocturnal insect with a visual system adapted for dim light. RESULTS: Whole-cell patch-clamped photoreceptors had high capacitances and input resistances, indicating large photosensitive rhabdomeres suitable for efficient photon capture and amplification of small photocurrents at low light levels. Two voltage-dependent potassium conductances were found in the photoreceptors: a delayed rectifier type (KDR) and a fast transient inactivating type (KA). Activation of KDR occurred during physiological voltage responses induced by light stimulation, whereas KA was nearly fully inactivated already at the dark resting potential. In addition, hyperpolarization of photoreceptors activated a small-amplitude inward-rectifying (IR) current mediated at least partially by chloride. Computer simulations showed that KDR shapes light responses by opposing the light-induced depolarization and speeding up the membrane time constant, whereas KA and IR have a negligible role in the majority of cells. However, larger KA conductances were found in smaller and rapidly adapting photoreceptors, where KA could have a functional role. CONCLUSIONS: The relative expression of KA and KDR in cockroach photoreceptors was opposite to the previously hypothesized framework for dark-active insects, necessitating further comparative work on the conductances. In general, the varying deployment of stereotypical K+ conductances in insect photoreceptors highlights their functional flexibility in neural coding.

Using Analytical Platform Technologies to Support Accelerated Product Development-Concept Review and Case Study.

The number of products being developed for serious conditions that are eligible for expedited programs has been increasing in recent years. This article presents an industry perspective on how to reduce analytical life cycle steps when using analytical platform technologies (APT) in support of accelerated biological product development. Strategies for life cycle steps for APT methods are conceptually reviewed within the framework of supporting chemistry, manufacturing, and control (CMC) development acceleration. Reduced method qualification, transfer, and validation studies could be performed, provided that the initially validated test method remains unchanged. A detailed case study is used to illustrate considerations for the initial method validation and subsequent APT verification studies. Considerations for APT implementation are discussed and suggestions are provided for the submission of APT information in regulatory filings.

The Time Machine framework: monitoring and prediction of biodiversity loss.

Transdisciplinary solutions are needed to achieve the sustainability of ecosystem services for future generations. We propose a framework to identify the causes of ecosystem function loss and to forecast the future of ecosystem services under different climate and pollution scenarios. The framework (i) applies an artificial intelligence (AI) time-series analysis to identify relationships among environmental change, biodiversity dynamics and ecosystem functions; (ii) validates relationships between loss of biodiversity and environmental change in fabricated ecosystems; and (iii) forecasts the likely future of ecosystem services and their socioeconomic impact under different pollution and climate scenarios. We illustrate the framework by applying it to watersheds, and provide system-level approaches that enable natural capital restoration by associating multidecadal biodiversity changes to chemical pollution.

Spread of Terbinafine-Resistant Trichophyton mentagrophytes Type VIII (India) in Germany-"The Tip of the Iceberg?"

Chronic recalcitrant dermatophytoses, due to Trichophyton (T.) mentagrophytes Type VIII are on the rise in India and are noteworthy for their predominance. It would not be wrong to assume that travel and migration would be responsible for the spread of T. mentagrophytes Type VIII from India, with many strains resistant to terbinafine, to other parts of the world. From September 2016 until March 2020, a total of 29 strains of T. mentagrophytes Type VIII (India) were isolated. All patients were residents of Germany: 12 females, 15 males and the gender of the remaining two was not assignable. Patients originated from India (11), Pakistan (two), Bangladesh (one), Iraq (two), Bahrain (one), Libya (one) and other unspecified countries (10). At least two patients were German-born residents. Most samples (21) were collected in 2019 and 2020. All 29 T. mentagrophytes isolates were sequenced (internal transcribed spacer (ITS) and translation elongation factor 1-α gene (TEF1-α)). All were identified as genotype VIII (India) of T. mentagrophytes. In vitro resistance testing revealed 13/29 strains (45%) to be terbinafine-resistant with minimum inhibitory concentration (MIC) breakpoints ≥0.2 µg/mL. The remaining 16 strains (55%) were terbinafine-sensitive. Point mutation analysis revealed that 10/13 resistant strains exhibited Phe397Leu amino acid substitution of squalene epoxidase (SQLE), indicative for in vitro resistance to terbinafine. Two resistant strains showed combined Phe397Leu and Ala448Thr amino acid substitutions, and one strain a single Leu393Phe amino acid substitution. Out of 16 terbinafine-sensitive strains, in eight Ala448Thr, and in one Ala448Thr +, new Val444 Ile amino acid substitutions were detected. Resistance to both itraconazole and voriconazole was observed in three out of 13 analyzed strains. Treatment included topical ciclopirox olamine plus topical miconazole or sertaconazole. Oral itraconazole 200 mg twice daily for four to eight weeks was found to be adequate. Terbinafine-resistant T. mentagrophytes Type VIII are being increasingly isolated. In Germany, transmission of T. mentagrophytes Type VIII from the Indian subcontinent to Europe should be viewed as a significant public health issue.

Preventing Cross-Contamination during Lyophilization: GMP and Occupational Cleaning Requirements for Nonproduct and Indirect Product-Contact Parts.

A detailed overview is provided for the possible patient exposure to highly potent active pharmaceutical ingredients (HPAPIs) from potential cross-contamination through the lyophilization process. The intent of this paper is to raise awareness of the risk(s) to patients and stimulate the implementation of adequate risk-based controls, such as containment process(es), use of adequate surrogates in cleaning validation/verification, and test method-sensitivity-based cleaning validation acceptance conditions. Although lyophilizers are considered to be nonproduct-contact surfaces because their surfaces and fixtures do not usually come into direct contact with the product, product contamination can occur at critical locations within a lyophilizer and/or during the unloading process. Contamination of the air because of released product particles can also create a risk. Therefore, special attention should be paid to HPAPIs, as the permitted daily exposures (PDEs) for patients are particularly low. During a lyophilizer cycle, areas of concern are spreading of the lyophilizer HPAPI powder because of air turbulence, contaminated plates, mechanical transfer systems, and spreading because of damaged vials or contaminated stainless steel or plastic surfaces. Specific considerations for contamination containment for the lyophilizer unloading process are presented. Suggestions are provided for the prevention of patient exposure through cross-contamination via direct-contact areas and prevention of manufacturing personnel exposure via non-direct-contact areas. A surface limit(s) of 1 PDE per square decimeter for nonproduct-contact surfaces inside a lyophilizer is proposed. Risk-based cleaning validation/verification strategies are discussed, with specific consideration of the quality control test method sensitivity expectations and use of suitable surrogates for lyophilized products in the cleaning verification studies.LAY ABSTRACT: This paper provides an overview of important points to consider during the manufacture of highly potent active pharmaceutical ingredients (HPAPI) with the intention to limit patient exposure and/or manufacturing personnel exposure to these highly toxic HPAPIs. HPAPI can potentially be spread during the freeze-drying process (lyophilization) and may cross-contaminate products. Manufacturing personnel and patients taking other freeze-dried products made in the same lyophilizer could be contaminated. It is therefore necessary to implement rigorous contamination controls. Within the lyophilizer, areas of concern are spreading of the lyophilizer HPAPI powder because of air turbulence, contaminated plates, mechanical transfer systems, and spreading because of damaged vials or contaminated stainless steel or plastic surfaces. Cleaning validation/verification studies, intended to demonstrate sufficient cleanability of the freeze-drying process as well as the recommended test method sensitivity to detect these highly toxic HPAPIs, are reviewed. Limits for the relevant production surface areas where cross-contamination and/or personnel exposure (through direct contact) could occur are proposed in this paper.

PDA Biosimilars Workshop Report (September 27-28, 2018)-Getting It Right the First Time for Biosimilar Marketing Applications.

This workshop report summarizes the presentations, the breakout session outcomes, and the speaker panel discussions from the PDA Biosimilars Workshop held September 27-28, 2018, in Washington, DC. This format was deliberately selected for the workshop with the expectation of delivering a post-workshop paper on current best practices and existing challenges for sponsors. The event, co-chaired by Dr. Stephan Krause (AstraZeneca Biologics) and Dr. Emanuela Lacana (CDER/FDA), was attended by 140 agency and industry representatives. The workshop was separated into three major sessions P1: Regulatory Perspective, P2: Challenges in Biosimilar Development, and P3: Demonstrating Analytical Similarity. Each of the three sessions started with agency and industry presentations. Participants then split into two concurrent roundtable discussion groups to hear the answers to questions that had been provided to all participants one week prior to the event. The sessions were recorded. This paper provides consolidated answers to specific case studies for current challenges to sponsors and agencies. In addition, the panel discussion notes following each breakout roundtable session, as well as brief talk summaries of all speakers, are provided. The first session explored the challenges encountered with submission of biosimilar marketing applications from the perspectives of regulatory agencies. Expectations for a successful submission of the chemistry, manufacturing, and controls (CMC) information were described. The second session addressed high-level technical challenges and how to avoid pitfalls frequently encountered during biosimilar candidate development, including data quality expectations, creation of the final control strategy, and strategic choices necessary for candidate selection and development. Both regulatory perspectives and industry experience were shared. The last session explored the use of statistical tools to provide meaningful contributions to the demonstration of analytical similarity. The presentations highlighted common issues and practical challenges that arise during the application of statistical tools.LAY ABSTRACT: Significant challenges are still-remaining for sponsors and agencies to successfully develop and license Biosimilars. A Biosimilars Workshop was therefore held on 27-28 September 2018 in Washington, DC, to find practical solutions to the remaining challenges. The workshop planning committee with members from industry and agencies prepared specific case studies focused on some of most difficult situations. The workshop was separated into three major sessions (P1 - Regulatory Perspective; P2 - Challenges in Biosimilar Development; P3 - Demonstrating Analytical Similarity) and each session attempted to provide practical solutions to the relevant case studies. This first session explored the challenges encountered with submission of biosimilar marketing applications from the regulatory agencies' perspectives. Expectations for a successful submission of the CMC information were described. The second session addressed high-level technical challenges frequently encountered during biosimilar candidate development, including data quality expectations, the creation of the final control strategy, and strategic choices necessary for candidate selection and development. The last session explored the use of statistical tools to provide meaningful contributions to the demonstration of analytical similarity and practical challenges that arise during the application of statistical tools.

Semi-Quantitative Analysis of Inherent Visible Particles for Biopharmaceutical Products.

Visible particles must be monitored as part of the control strategy for pharmaceutical products. Extraneous (foreign) particles are not acceptable in parenteral drug products. In biopharmaceuticals, formation of protein particles is recognized as an inherent quality attribute. All protein therapeutics contain particles that vary greatly in visibility and size from invisible (sub-micron) to visible (millimeter) and, as part of the control strategy, biopharmaceutical companies are required to monitor and minimize the presence of visible and sub-visible particles in their products. There is an industry-wide unmet need for particle standards for visual inspection of protein therapeutics. A new, semi-quantitative method using particle standards for assessing the levels of small, inherent visible particles is presented. This method can be used during product development to identify a formulation that minimizes particle formation and also during release and stability testing to monitor and control inherent proteinaceous visible particles. LAY ABSTRACT: Visible particles must be monitored as part of the control strategy for parenteral biopharmaceutical drug products. In these products, formation of protein particles is a natural occurrence. All protein drugs contain particles that vary greatly in visibility and size from invisible (sub-micron) to visible (millimeter), and pharmaceutical companies are required to monitor and minimize the presence of visible and sub-visible particles in their products. There is an industry-wide unmet need for particle standards for visual inspection of protein drugs. A new, semi-quantitative method using particle standards for assessing the levels of small, naturally occurring visible particles is presented. This method can be used during drug development to identify a formulation that minimizes particle formation and also during testing of final clinical or commercial drug product to monitor and control naturally occurring proteinaceous visible particles.

PCMO L01-Setting Specifications for Biological Investigational Medicinal Products.

UNLABELLED: This paper provides overall guidance and best practices for the setting of specifications for clinical biological drug substances and drug products within the framework of ICH guidelines on pharmaceutical development [Q8(R2) and Q11], quality risk management (Q9), and quality systems (Q10). A review is provided of the current regulatory expectations for the specification setting process as part of a control strategy during product development, pointing to existing challenges for the investigational new drug/investigational medicinal product dossier (IND/IMPD) sponsor. A case study illustrates how the investigational medicinal product specification revision process can be managed within a flexible quality system, and how specifications can be set and justified for early and late development stages. LAY ABSTRACT: This paper provides an overview for the setting of product specifications for investigational medicinal products used in clinical trials. A case study illustrates how product specifications of investigational medicinal products can be justified and managed within a modern product quality system.

Elementary and macroscopic light-induced currents and their Ca(2+)-dependence in the photoreceptors of Periplaneta americana.

In a microvillar photoreceptor, absorption of an incident photon initiates a phototransduction reaction that generates a depolarizing light-induced current (LIC) in the microvillus. Although in-depth knowledge about these processes in photoreceptors of the fruitfly Drosophila is available, not much is known about their nature in other insect species. Here, we present description of some basic properties of both elementary and macroscopic LICs and their Ca(2+)-dependence in the photoreceptors of a dark-active species, the cockroach Periplaneta americana. Cockroach photoreceptors respond to single photon absorptions by generating quantum bumps with about 5-fold larger amplitudes than in Drosophila. At the macroscopic current level, cockroach photoreceptors responded to light with variable sensitivity and current waveform. This variability could be partially attributed to differences in whole-cell capacitance. Transient LICs, both elementary and macroscopic, showed only moderate dependence on extracellular Ca(2+). However, with long light pulses, response inactivation was largely abolished and the overall size of LICs increased when extracellular Ca(2+) was omitted. Finally, by determining relative ionic permeabilities from reversals of LICs, we demonstrate that when compared to Drosophila, cockroach light-gated channels are only moderately Ca(2+)-selective.

Characterization of the initial level and migration of silicone oil lubricant in empty prefilled syringes for biologics using infrared spectroscopy.

Glass prefillable syringes are lubricated with silicone oil to ensure functionality and a consistent injection for the end user. If excessive silicone is applied, droplets could potentially result in aggregation of sensitive biopharmaceuticals or clouding of the solution. Therefore, monitoring and optimization of the applied silicone layer is critical for prefilled syringe development. The hydrophobic properties of silicone oil, the potential for assay interference, and the very small quantities applied to prefilled syringes present a challenge for the development of a suitable assay. In this work we present a rapid and simple Fourier transform infrared (FTIR) spectroscopy method for quantitation of total silicone levels applied to prefilled syringes. Level-dependent silicone oil migration occurred over time for empty prefilled syringes stored tip-up. However, migration from all prefilled syringes with between 0.25 and 0.8 mg of initial silicone oil resulted in a stable limiting minimum level of between 0.15 and 0.26 mg of silicone in the syringe reached after 1 to 4 years of empty tip-up storage. The results of the FTIR assay correlated well with non-destructive reflectometry characterization of the syringes. This assay can provide valuable data for selection of a robust initial silicone oil target and quality control of prefilled syringes intended for biopharmaceuticals. LAY ABSTRACT: Glass prefillable syringes are lubricated with silicone oil to ensure functionality and a consistent injection for the end user. If excessive silicone is applied, droplets could potentially result in aggregation of sensitive biopharmaceuticals or clouding of the solution. Therefore, monitoring and optimization of the applied silicone layer is critical for prefilled syringe development. The hydrophobic properties of silicone oil, the potential for assay interference, and the very small quantities applied to prefilled syringes present a challenge for the development of a suitable assay. In this work we present a rapid and simple Fourier transform infrared (FTIR) spectroscopy method for quantitation of total silicone levels applied to prefilled syringes. Level-dependent silicone oil migration occurred over time for empty prefilled syringes stored tip-up. However, migration from all prefilled syringes with between 0.25 and 0.8 mg of initial silicone oil resulted in a stable limiting minimum level of between 0.15 and 0.26 mg of silicone in the syringe reached after 1 to 4 years of empty tip-up storage. The results of the FTIR assay correlated well with non-destructive reflectometry characterization of the syringes. This assay can provide valuable data for selection of a robust initial silicone oil target and quality control of prefilled syringes intended for biopharmaceuticals.

A Thorough QT Study of Teduglutide in Healthy Subjects.

Teduglutide, an analog of the endogenous hormone glucagon-like peptide-2, is currently being developed for the treatment of short bowel syndrome. This study investigated the potential effects of teduglutide on cardiac conduction and repolarization. Seventy-two healthy volunteers underwent 4 treatment periods in randomized order with a single subcutaneous injection of placebo, 5 and 20 mg teduglutide, and a single oral 400-mg dose of moxifloxacin. The primary variable to investigate the effect on cardiac repolarization was the difference between QTcF after administration versus predose. The observed upper bounds of the 95% one-sided confidence intervals were 3.0 ms (5 mg) and 4.5 ms (20 mg). Arithmetic mean curves of QTcF intervals over time of both doses of teduglutide and of placebo were almost superposable. Assay sensitivity for the positive control moxifloxacin was shown. In conclusion, teduglutide at intended therapeutic and supratherapeutic doses had no effect on cardiac repolarization. No safety concerns were identified. Treatment with teduglutide was well tolerated.

Light-dependent modulation of Shab channels via phosphoinositide depletion in Drosophila photoreceptors.

The Drosophila phototransduction cascade transforms light into depolarizations that are further shaped by activation of voltage-dependent K+ (Kv) channels. In whole-cell recordings of isolated photoreceptors, we show that light selectively modulated the delayed rectifier (Shab) current. Shab currents were increased by light with similar kinetics to the light-induced current itself (latency approximately 20 ms), recovering to control values with a t(1/2) of approximately 60 s in darkness. Genetic disruption of PLCbeta4, responsible for light-induced PIP(2) hydrolysis, abolished this light-dependent modulation. In mutants of CDP-diaclyglycerol synthase (cds(1)), required for PIP(2) resynthesis, the modulation became irreversible, but exogenously applied PIP(2) restored reversibility. The modulation was accurately and reversibly mimicked by application of PIP(2) to heterologously expressed Shab channels in excised inside-out patches. The results indicate a functionally implemented mechanism of Kv channel modulation by PIP(2) in photoreceptors, which enables light-dependent regulation of signal processing by direct coupling to the phototransduction cascade.

Identification and selective inhibition of the channel mode of the neuronal GABA transporter 1.

The function of GAT1, the transporter for the inhibitory neurotransmitter GABA, is characterized by expression in Xenopus laevis oocytes and measurements of GABA-induced uptake of [3H]GABA, 22Na+, and 36Cl-, and GABA-evoked currents under voltage-clamp conditions. N-[4,4-Diphenyl-3-butenyl]-nipecotic acid (SKF-89976-A), a specific inhibitor of GAT1, is used in our system as a pharmacological tool. The GABA-evoked current can be decomposed into a transport current, which is coupled to the GABA uptake, and a transmitter-gated current, which is uncoupled from the GABA uptake. The transport current results from a fixed stoichiometry of 1 GABA/2 Na+/1 Cl- transported during each cycle, as determined by radioactive tracer flux measurements. The transmitter-gated current is mediated by an Na+-conductance pathway. As a competitive inhibitor for GABA uptake, SKF-89976-A can separate the two current components. The GABA uptake is blocked with a K(I) value of approximately 7 microM, whereas the uncoupled transmitter-gated current is inhibited with a K(I) value of approximately 0.03 microM. Thus, the results of this study not only identify the transport mode and the channel mode of GAT1 but also raise the possibility of separating these components in a physiological environment.