A 3D Model of the Human Lung Airway for Evaluating Permeability of Inhaled Drugs.

Current in vitro cell-based methods, relying on single cell types, have structural and functional limitations in determining lung drug permeability, which is a contributing factor affecting both local and systemic drug levels. To address this issue, we investigated a 3D human lung airway model generated using a cell culture insert, wherein primary human lung epithelial and endothelial cells were cocultured at an air-liquid interface (ALI). To ensure that the cell culture mimics the physiological and functional characteristics of airway tissue, the model was characterized by evaluating several parameters such as cellular confluency, ciliation, tight junctions, mucus-layer formation, transepithelial electrical resistance, and barrier function through assaying fluorescein isothiocyanate-dextran permeability.

Lessons learned from regulatory submissions involving endogenous therapeutic analyte bioanalysis.

Endogenous therapeutic analytes include hormones, neurotransmitters, vitamins, fatty acids and inorganic elements that are naturally present in the body because either the body produces them or they are present in the normal diet. The accurate measurement of endogenous therapeutic analytes poses a challenge when the administered exogenous therapeutic analyte and its endogenous counterpart cannot be distinguished. In this article, real case examples with endogenous therapeutic analyte bioanalysis during drug development in support of regulatory submissions are collected and presented.

New science, drug regulation, and emergent public health issues: The work of FDA's division of applied regulatory science.

The U.S. Food and Drug Administration (FDA) Division of Applied Regulatory Science (DARS) moves new science into the drug review process and addresses emergent regulatory and public health questions for the Agency.

A Bioanalytical Method for Quantification of N-nitrosodimethylamine (NDMA) in Human Plasma and Urine with Different Meals and following Administration of Ranitidine.

Control of N-nitrosoamine impurities is important for ensuring the safety of drug products. Findings of nitrosamine impurities in some drug products led FDA to develop new guidance providing recommendations for manufacturers towards prevention and detection of nitrosamine impurities in pharmaceutical products. One of these products, ranitidine, also had a published in vivo study, which has since been retracted by its authors, suggesting a potential for in vivo conversion of ranitidine to the probable human carcinogen, N-nitrosodimethylamine (NDMA).

Determination of five positive control drugs in hERG external solution (buffer) by LC-MS/MS to support in vitro hERG assay as recommended by ICH S7B.

ICH S7B recommends screening for hERG channel block using patch clamp recordings to assess a drug's proarrhythmic risk. Block of the hERG channel has been associated with clinical QT prolongation as well as the rare, but potentially fatal ventricular tachyarrhythmia Torsade de Pointes (TdP). During recording, drug concentrations perfused to the cells can deviate from nominal concentrations due to molecule-specific properties (such as non-specific binding), thereby introducing error when assessing drug potency.

Considerations for Use of Pharmacodynamic Biomarkers to Support Biosimilar Development - (III) A Randomized Trial with Interferon Beta-1a Products.

The US Food and Drug Administration (FDA) has taken steps to bring efficiency to the development of biosimilars, including establishing guidance for the use of pharmacokinetic and pharmacodynamic (PD) similarity study data without a comparative clinical study with efficacy end point(s). To better understand the potential role for PD biomarkers in biosimilar development and inform best practices for biomarker selection and analysis, we conducted a randomized, double-blinded, placebo-controlled, single-dose, parallel-arm clinical study in healthy participants. Eighty-four healthy participants (n = 12 per dose arm) received either placebo or one of three doses of either interferon β-1a (7.

Evaluating the Utility of Proteomics for the Identification of Circulating Pharmacodynamic Biomarkers of IFNβ-1a Biologics.

Proteomics has the potential to identify pharmacodynamic (PD) biomarkers for similarity assessment of proposed biosimilars without relying on clinical efficacy end points. In this study, with 36 healthy participants randomized to therapeutic doses of interferon-beta 1a products (IFNβ-1a) or pegylated-IFNβ-1a (pegIFNβ-1a) approved to treat multiple sclerosis or placebo, we evaluated the utility of a proteomic assay that profiles > 7,000 plasma proteins. IFNβ-1a and pegIFNβ-1a resulted in 248 and 528 differentially expressed protein analytes, respectively, between treatment and placebo groups over the time course.

Considerations for Use of Pharmacodynamic Biomarkers to Support Biosimilar Development - (I) A Randomized Trial with PCSK9 Inhibitors.

US Food and Drug Administration (FDA) guidance outlines how biosimilars can be developed based on pharmacokinetic (PK) and pharmacodynamic (PD) similarity study data in lieu of a comparative clinical efficacy study. There is a paucity of PD comparability studies in biosimilar development, leaving open questions about how best to plan these studies. To that end, we conducted a randomized, double-blinded, placebo-controlled, single-dose, parallel-arm clinical study in healthy participants to evaluate approaches to address information gaps, inform analysis best practices, and apply emerging technologies in biomarker characterization.

Effect of Paroxetine or Quetiapine Combined With Oxycodone vs Oxycodone Alone on Ventilation During Hypercapnia: A Randomized Clinical Trial.

Importance: Opioids can cause severe respiratory depression by suppressing feedback mechanisms that increase ventilation in response to hypercapnia. Following the addition of boxed warnings to benzodiazepine and opioid products about increased respiratory depression risk with simultaneous use, the US Food and Drug Administration evaluated whether other drugs that might be used in place of benzodiazepines may cause similar effects.

Objective: To study whether combining paroxetine or quetiapine with oxycodone, compared with oxycodone alone, decreases the ventilatory response to hypercapnia.

Considerations for Use of Pharmacodynamic Biomarkers to Support Biosimilar Development - (II) A Randomized Trial with IL-5 Antagonists.

The US Food and Drug Administration (FDA) guidance describes how pharmacodynamic (PD) biomarkers can be used to address residual uncertainty and demonstrate no clinically meaningful differences between a proposed biosimilar and its reference product without relying on clinical efficacy end point(s). Pilot studies and modeling can inform dosing for such PD studies. To that end, we conducted a randomized, double-blinded, placebo-controlled, single-dose, parallel-arm clinical study in healthy participants to evaluate approaches to address information gaps, inform best practices for analysis of biomarker samples and study results, and apply emerging technologies in biomarker characterization.

hERG block potencies for 5 positive control drugs obtained per ICH E14/S7B Q&As best practices: Impact of recording temperature and drug loss.

According to the ICH S7B guideline, drug candidates are screened for hERG block prior to first-in-human testing to predict the likelihood of delayed repolarization associated with a rare, but life-threatening, ventricular tachyarrhythmia. The new ICH E14 Q&As guideline allows hERG results to be used in later clinical development for decision-making (Q&As 5.1 and 6.

In Vitro Testing of Sunscreens for Dermal Absorption: Method Comparison and Rank Order Correlation with In Vivo Absorption.

Evaluating the dermal absorption of sunscreen UV filters requires the development of a bio-predictable in vitro permeation test (IVPT). This work describes the comparison of two IVPT methods and rank order correlations of in vitro absorption (skin permeation and retention) with the in vivo absorption (AUC and skin retention) of sunscreens. The IVPT was compared regarding the following elements: (1) application of a single finite dose vs.

Effect of Oral Ranitidine on Urinary Excretion of N-Nitrosodimethylamine (NDMA): A Randomized Clinical Trial.

Importance: In 2019, the US Food and Drug Administration (FDA) received a citizen petition indicating that ranitidine contained the probable human carcinogen N-nitrosodimethylamine (NDMA). In addition, the petitioner proposed that ranitidine could convert to NDMA in humans; however, this was primarily based on a small clinical study that detected an increase in urinary excretion of NDMA after oral ranitidine consumption.

Objective: To evaluate the 24-hour urinary excretion of NDMA after oral administration of ranitidine compared with placebo.

Effects of sedative psychotropic drugs combined with oxycodone on respiratory depression in the rat.

Following a decision to require label warnings for concurrent use of opioids and benzodiazepines and increased risk of respiratory depression and death, the US Food and Drug Administratioin (FDA) recognized that other sedative psychotropic drugs may be substituted for benzodiazepines and be used concurrently with opioids. In some cases, data on the ability of these alternatives to depress respiration alone or in conjunction with an opioid are lacking. A nonclinical in vivo model was developed that could detect worsening respiratory depression when a benzodiazepine (diazepam) was used in combination with an opioid (oxycodone) compared to the opioid alone based on an increased arterial partial pressure of carbon dioxide (pCO ).

Novel simultaneous method for the determination of avobenzone and oxybenzone in human plasma by UHPLC-MS/MS with phospholipid removal pretreatment: An application to a sunscreen clinical trial.

Application of sunscreen is one of many ways to protect skin from the harmful effects of UV radiation. Sunscreen products are widely used and regulated as over-the-counter drug products in the United States. The U.

Characterizing the reproducibility in using a liver microphysiological system for assaying drug toxicity, metabolism, and accumulation.

Liver microphysiological systems (MPSs) are promising models for predicting hepatic drug effects. Yet, after a decade since their introduction, MPSs are not routinely used in drug development due to lack of criteria for ensuring reproducibility of results. We characterized the feasibility of a liver MPS to yield reproducible outcomes of experiments assaying drug toxicity, metabolism, and intracellular accumulation.

Developing an animal model to detect drug-drug interactions impacting drug-induced respiratory depression.

Opioids and benzodiazepines were frequently co-prescribed to patients with pain and psychiatric or neurological disorders; however, co-prescription of these drugs increased the risk for severe respiratory depression and death. Consequently, the U.S.

Effect of Sunscreen Application on Plasma Concentration of Sunscreen Active Ingredients: A Randomized Clinical Trial.

Importance: A prior pilot study demonstrated the systemic absorption of 4 sunscreen active ingredients; additional studies are needed to determine the systemic absorption of additional active ingredients and how quickly systemic exposure exceeds 0.5 ng/mL as recommended by the US Food and Drug Administration (FDA).

Objective: To assess the systemic absorption and pharmacokinetics of the 6 active ingredients (avobenzone, oxybenzone, octocrylene, homosalate, octisalate, and octinoxate) in 4 sunscreen products under single- and maximal-use conditions.

A high-throughput bioanalytical assay to support pharmacokinetic interaction study of oxycodone and diazepam in Sprague Dawley rats.

Benzodiazepines potentiate respiratory depression when combined with an opioid leading the U.S Food and Drug Administration (FDA) to recommend updating the labels of these products with a boxed warning for respiratory depression with co-use. Potential respiratory depression upon co-administration of opioids with some psychotropic drugs is not well understood.

Quantitative analysis of underivatized 17 β-estradiol using a high-throughput LC-MS/MS assay - Application to support a pharmacokinetic study in ovariectomized guinea pigs.

Difference in female sex hormone, β-estradiol (E), levels can contribute to sex differences in biological processes that underlie target tissue functions (QT interval), vulnerability to diseases (hepatitis or HIV), and response toward therapies. Accurate quantification of plasma E level is thus an important aspect in both basic science research examining hormone-regulated physiological mechanisms and in clinical settings to support patient care associated with altered E levels. Due to lack of a high-throughput high-sensitivity analytical method, we developed and validated a LC-MS/MS assay for accurate low-level quantification of E and demonstrated its application to a guinea pig pharmacokinetic study in which guinea pigs were treated with 10 or 40 μg/kg E subcutaneously and blood samples collected at 0 (pre-dose), 0.

Evaluation of Immunocompetent Urinary Tract Infected Balb/C Mouse Model For the Study of Antibiotic Resistance Development Using CFT073 Infection.

Urinary tract infections (UTI) are common worldwide and are becoming increasingly difficult to treat because of the development of antibiotic resistance. Immunocompetent murine models of human UTI have been used to study pathogenesis and treatment but not for investigating resistance development after treatment with antibiotics. In this study, intravesical inoculation of uropathogenic CFT073 in immunocompetent Balb/c mice was used as a model of human UTI.

Simultaneous UHPLC-MS/MS method of estradiol metabolites to support the evaluation of Phase-2 metabolic activity of induced pluripotent stem cell derived hepatocytes.

The goal of this study was to develop and validate a high-throughput UHPLC-MS/MS method for simultaneous quantitation of three estradiol metabolites namely estradiol 3-β-D-glucuronide (E3G), estradiol 17-β-D-glucuronide (E17G) and estradiol 3-sulfate (E3S) in cell culture medium to support the characterization of metabolic function of induced pluripotent stem cell (iPSC) derived hepatocytes. To achieve this goal, a simple protein precipitation method was used for sample cleanup. All the metabolites were separated chromatographically using a C-18 column where 10 mM ammonium acetate and acetonitrile was used in gradient flow for 4 min.

Novel High-Throughput Quantitation of Potent hERG Blocker Dofetilide in Human Plasma by Liquid Chromatography Tandem Mass Spectrometry: Application in a Phase 1 ECG Biomarker Validation Study.

The authors developed a novel, sensitive high-throughput ultra-performance liquid chromatography-tandem mass spectrometric method for the determination of dofetilide in human plasma. To compensate for the matrix effect, a deuterated internal standard was used. The method employed a very low sample volume (50 μL) of plasma for sample processing by using simple protein precipitation extraction in a 96-well plate.