Pharmacokinetic Curves Research Articles

DeepCt: Predicting Pharmacokinetic Concentration-Time Curves and Compartmental Models from Chemical Structure Using Deep Learning.

After initial triaging using in vitro absorption, distribution, metabolism, and excretion (ADME) assays, pharmacokinetic (PK) studies are the first application of promising drug candidates in living mammals. Preclinical PK studies characterize the evolution of the compound's concentration over time, typically in rodents' blood or plasma. From this concentration-time (C-t) profiles, PK parameters such as total exposure or maximum concentration can be subsequently derived. An early estimation of compounds' PK offers the promise of reducing animal studies and cycle times by selecting and designing molecules with increased chances of success at the PK stage. Even though C-t curves are the major readout from a PK study, most machine learning-based prediction efforts have focused on the derived PK parameters instead of C-t profiles, likely due to the lack of approaches to model the underlying ADME mechanisms. Herein, a novel deep learning approach termed DeepCt is proposed for the prediction of C-t curves from the compound structure. Our methodology is based on the prediction of an underlying mechanistic compartmental PK model, which enables further simulations, and predictions of single- and multiple-dose C-t profiles.

Evaluation of the pharmacokinetics of an experimental combined form of IFNα and IFNγ for intranasal use

Polypous rhinosinusitis is a chronic inflammatory disease of the nasal mucosa and paranasal sinuses. Recombinant interferon has antiproliferative activity and corrects the deficiency of endogenous regulatory molecules, which allows us to consider this class of immunotropic drugs as a promising component of conservative immunotherapy for polyposis rhinosinusitis. Purpose of the study: To select the optimal composition of the experimental composition of interferons and evaluate their pharmacokinetic parameters in laboratory animals.For laboratory evaluation of the effectiveness of the auxiliary components of the proposed composition in creating a local effect, Wistar rats in the amount of 30 animals were selected, to which the proposed form of the drug (IFN1) was administered once intranasally. The control group included 30 animals that were alternately administered intranasally with a similar dose of IFNα2b and IFNγ dissolved in water for injection (IFN2). Quantitative determination of interferon concentration in blood samples was carried out using the enzyme immunoassay method. To assess the dependence of changes in concentrations in the blood of animals on the time elapsed after their administration, standard pharmacokinetic models were used. Next, the integral from the initial moment of time to infinity was determined, which corresponded to the area under the pharmacokinetic curve and made it possible to calculate a number of pharmacokinetic characteristics.The following indicators were obtained: 1) Area under the pharmacokinetic curve (AUCt) ng/ml/min – IFN1 = 683.0; IFN2 = 1707.7. 2) Absorption constant (Kp) – IFN1 = 0.13096; IFN2 = 0.03836. 3) Suction constant (Kel) – IFN1 = 0.00177; IFN2 = 0.00317. 4) Clearance (Cl) ml/min – IFN1 = 129.35; IFN2 = 51.73.Based on the differences in the values of pharmacokinetic parameters (AUCt) for the IFN1 and IFN2 preparations, it can be concluded that the use of a composition based on chitosan, succinic acid and DMSO leads to a pronounced retention of interferon in the nasal mucosa, which provides a pronounced local therapeutic effect and allows for fewer systemic adverse reactions. This composition is suitable for further clinical studies of the effectiveness of immunotherapy for polyposis rhinosinusitis.

The Pharmacokinetics and Liver-Targeting Evaluation of Silybin Liposomes Mediated by the NTCP/OCTN2 Dual Receptors.

The disadvantage of a traditional dosage regimen is the inability to deliver a sufficient drug concentration to the lesion site, which can result in adverse side effects due to nonspecific drug delivery. Actively targeting hepatic cells is a promising therapeutic strategy for liver disease. In this study, l-carnitine and a targeting peptide derived from the hepatitis B virus large envelope protein were used to modify liposomes for drug delivery to the liver through the sodium taurocholate cotransporting polypeptide (NTCP) and the organic cation/carnitine transporter 2 (OCTN2) receptors. Silybin was selected as the model drug. The solubility of silybin can reach 0.3 mg/mL after encapsulation in liposomes. The NTCP-specific and OCTN2-accelerated Myrcludex B and l-carnitine dual-modified liposomes were validated in vitro. The uptake of coumarin-6 in dual ligand-modified liposomes by hepatocytes was up to 2.36 μg/mg compared with unmodified liposomes (1.05 μg/mg). The pharmacokinetics and targeting abilities of various liposome formulations were evaluated in Kunming mice. Targeted liposomes increased the concentration of silybin and prolonged the drug's retention time in the liver. The area under the liver's pharmacokinetic curve of targeted liposomes was twice that of silybin injection, suggesting the promising application potential of silybin-loaded hepatotropic nanovesicles.

Ionic co-aggregates based intravenous drug delivery: Evaluation on kinetics and distribution of the drug payloads and nanocarriers

Surfactants are crucial in formulating poorly soluble drugs but lead to serious side effects due to PEG chains. Novel supra-amphiphiles consisting of fatty acids and choline are developed, which spontaneously form ionic co-aggregates (ICAs) in water and exhibit strong solubilizing capacity. Paclitaxel (PTX) is adopted as a model drug here to evaluate the feasibility of choline oleate-based ICAs in the intravenous delivery of poorly soluble drugs by comparing the kinetics and distribution of payloads and nanocarriers. Choline oleate presents a maximum 10-fold enhancement in solubilizing capacity to PTX than Cremophor EL (CreEL), enabling a one-tenth use level in the formulation. Aggregation-caused quenching probes are utilized to evaluate the kinetics and biodistribution of ICAs or CreEL-based micelles (MCs). A huge gap is found between the pharmacokinetic and particokinetic curves of either nanocarrier, indicating fast leakage. ICAs lead to faster PTX leakage in blood circulation but higher PTX distribution to organs than MCs. MCs present a longer circulation in blood but a slower distribution to organs than ICAs. ICAs do not arise adverse reactions in rats following repeated injections, while MCs cause pathological changes in varying degrees. In conclusion, choline oleate-based ICAs provide an alternative to surfactants in formulating poorly soluble drugs.

Population pharmacokinetic study and application of ticagrelor and AR-C124910XX after percutaneous coronary intervention in Chinese patients with acute coronary syndrome.

This study aimed to understand the pharmacokinetics of ticagrelor in Chinese patients with acute coronary syndrome (ACS), identify influencing factors, and inform ticagrelor treatment optimization. Data from 195 ACS patients, including 491 plasma ticagrelor concentration timepoints and clinical information, were analyzed using NONMEN for pharmacokinetic (PK) parameter factors. The model underwent internal validation with bootstrap methodology. The PK curve of ticagrelor was well delineated using a one disposition compartment model with first-order absorption rate constant, 0.67/h. When the direct bilirubin levels and white plasma cell counts increased, female patients showed decreased glomerular filtration rate, decreased ticagrelor clearance rate, and increased exposure. When the direct bilirubin levels increased and body weight and hemoglobin decreased, rs6787801 was GG compared with AA and GA, the ticagrelor metabolite clearance rate decreased and exposure increased. The study offers key insights into ticagrelor's dose-exposure relationship post-percutaneous coronary intervention in ACS patients, highlighting factors critical for personalized treatment strategies.

Development and evaluation of a lutein-fortified yoghurt: Stability assessment, sensory properties and human bioavailability study

Lutein is a carotenoid that humans obtain primarily from green-leafy vegetables. However, due to generally low consumption of these foods, this bioactive is not sufficiently consumed. Therefore, there is growing interest in developing lutein-fortified foods to provide an additional source of lutein supplementation. In this study, we developed a lutein-fortified yoghurt and conducted a 72-hour single-dose bioavailability study in human subjects. Lutein remained stable in the yoghurt over shelf life at 14.6 mg of lutein per 100 g of yoghurt. Sensory evaluation yielded results similar to a lutein-free yoghurt. In the bioavailability study, consuming 100 g of lutein-fortified yoghurt significantly increased the average serum concentration of lutein by 1946.86 ± 1514.72 h μg·L−1 in human subjects, following a typical pharmacokinetic curve of absorption and decline. These findings confirm that our lutein-fortified yoghurt is suitable for commercial use and effectively enhances people’s serum lutein levels.

Model-informed dose optimization of mycophenolic acid in pediatric kidney transplant patients

PurposeWe aimed to develop and evaluate a population PK model of mycophenolic acid (MPA) in pediatric kidney transplant patients to aid MPA dose optimization.MethodsData were collected from pediatric kidney transplant recipients from a Dutch academic hospital (Radboudumc, the Netherlands). Pharmacokinetic model-building and model-validation analyses were performed using NONMEM. Subsequently, we externally evaluated the final model using data from another academic hospital. The final model was used to develop an optimized dosing regimen.ResultsThirty pediatric patients were included of whom 266 measured MPA plasma concentrations, including 20 full pharmacokinetic (PK) curves and 24 limited sampling curves, were available. A two-compartment model with a transition compartment for Erlang-type absorption best described the data. The final population PK parameter estimates were Ktr (1.48 h−1; 95% CI, 1.15–1.84), CL/F (16.0 L h−1; 95% CI, 10.3–20.4), Vc/F (24.9 L; 95% CI, 93.0–6.71E25), Vp/F (1590 L; 95% CI, 651–2994), and Q/F (36.2 L h−1; 95% CI, 9.63–74.7). The performance of the PK model in the external population was adequate. An optimized initial dose scheme based on bodyweight was developed. With the licensed initial dose, 35% of patients were predicted to achieve the target AUC, compared to 42% using the optimized scheme.ConclusionWe have successfully developed a pharmacokinetic model for MPA in pediatric renal transplant patients. The optimized dosing regimen is expected to result in better target attainment early in treatment. It can be used in combination with model-informed follow-up dosing to further individualize the dose when PK samples become available.

Modelling the nicotine pharmacokinetic profile for e-cigarettes using real time monitoring of consumers’ physiological measurements and mouth level exposure

Pharmacokinetic (PK) studies can provide essential information on abuse liability of nicotine and tobacco products but are intrusive and must be conducted in a clinical environment. The objective of the study was to explore whether changes in plasma nicotine levels following use of an e-cigarette can be predicted from real time monitoring of physiological parameters and mouth level exposure (MLE) to nicotine before, during, and after e-cigarette vaping, using wearable devices. Such an approach would allow an -effective pre-screening process, reducing the number of clinical studies, reducing the number of products to be tested and the number of blood draws required in a clinical PK study Establishing such a prediction model might facilitate the longitudinal collection of data on product use and nicotine expression among consumers using nicotine products in their normal environments, thereby reducing the need for intrusive clinical studies while generating PK data related to product use in the real world.An exploratory machine learning model was developed to predict changes in plasma nicotine levels following the use of an e-cigarette; from real time monitoring of physiological parameters and MLE to nicotine before, during, and after e-cigarette vaping. This preliminary study identified key parameters, such as heart rate (HR), heart rate variability (HRV), and physiological stress (PS) that may act as predictors for an individual’s plasma nicotine response (PK curve). Relative to baseline measurements (per participant), HR showed a significant increase for nicotine containing e-liquids and was consistent across sessions (intra-participant). Imputing missing values and training the model on all data resulted in 57% improvement from the original’learning’ data and achieved a median validation R2 of 0.70.The study is in its exploratory phase, with limitations including a small and non-diverse sample size and reliance on data from a single e-cigarette product. These findings necessitate further research for validation and to enhance the model's generalisability and applicability in real-world settings. This study serves as a foundational step towards developing non-intrusive PK models for nicotine product use.

Assessment of sorbitol clearance in induced acute liver failure

The study of substance clearance plays an important role in the diagnosis of liver pathologies. Increased or decreased clearance of certain substances may indicate hepatobiliary disorders, including at the initial stages of the development of such pathologies, which allows us to evaluate the predictive potential of these assessment methods as high. The scientific literature provides detailed and statistically proven data on the use of substances such as galactose, amidopyrine, sorbitol and others in diagnostic protocols. Each substance is characterized by its own level of clearance, which allows one to obtain a comprehensive picture of the functioning of the hepatobiliary system. However, for most of the above exogenous substances, information in the scientific literature is either indicated in relation to humane medicine, or consists of pilot studies on a small number of animals, which requires additional testing of this kind to develop a statistically reliable array of data obtained. The purpose of this study is to conduct an experimental study aimed at studying changes in the pharmacokinetics of exogenous sorbitol in the blood plasma of laboratory animals with acute liver failure. The level of sorbitol was determined by the colorimetric Corcoran and Page method with modification (using potassium periodate and chromotropic acid, the method takes into account the calculated sorbitol indicator from the sum of polyols) using a UV-100 spectrophotometer (manufacturer – Shanghai Mapada Instruments Co., Ltd., China) for 12 hours (step – 2 hours) in blood plasma deproteinized using 0.4 M lithium perchlorate, obtained by venipuncture of the tail vein. Comparing pharmacokinetic curves with each other, it should be noted that in animals with acute liver failure, the graphical representation of sorbitol levels is similar to the inverse exponential, characterized by a sharp systematic decrease, while in clinically healthy animals the graphical representation of sorbitol levels is similar to the branch of a parabola, characterized by “smoothness” » reduction. The pharmacokinetic curves obtained in this study, which describe the levels of exogenous sorbitol in the blood plasma, can be used in the future as one of the methods for the early diagnosis of such pathologies.

Clustering plasma concentration-time curves: applications ofunsupervised learning in pharmacogenomics

ABSTRACT Pharmaceutical researchers are continually searching for techniques to improve both drug development processes and patient outcomes. An area of recent interest is the potential for machine learning (ML) applications within pharmacology. One such application not yet given close study is the unsupervised clustering of plasma concentration-time curves, hereafter, pharmacokinetic (PK) curves. In this paper, we present our findings on how to cluster PK curves by their similarity. Specifically, we find clustering to be effective at identifying similar-shaped PK curves and informative for understanding patterns within each cluster of PK curves. Because PK curves are time series data objects, our approach utilizes the extensive body of research related to the clustering of time series data as a starting point. As such, we examine many dissimilarity measures between time series data objects to find those most suitable for PK curves. We identify Euclidean distance as generally most appropriate for clustering PK curves, and we further show that dynamic time warping, Fréchet, and structure-based measures of dissimilarity like correlation may produce unexpected results. As an illustration, we apply these methods in a case study with 250 PK curves used in a previous pharmacogenomic study. Our case study finds that an unsupervised ML clustering with Euclidean distance, without any subject genetic information, is able to independently validate the same conclusions as the reference pharmacogenomic results. To our knowledge, this is the first such demonstration. Further, the case study demonstrates how the clustering of PK curves may generate insights that could be difficult to perceive solely with population level summary statistics of PK metrics.

Abstract 6703: Innovative mRNA strategies to encode CD19/CD3 T cell engagers in the treatment of B cell hematological malignancies

Abstract The advent of T Cell Engager (TCE) immunotherapies marks a transformative shift in cancer treatment paradigms, introducing a novel action mechanism. Blinatumomab, a bispecific CD19/CD3 TCE, has shown remarkable efficacy in treating refractory or relapsed B-cell Acute Lymphoblastic Leukaemia (B-ALL), including cases resistant to conventional chemotherapy, leading to its global approval for B-ALL management. Despite its pronounced clinical success, Blinatumomab faces challenges with patient adherence, primarily due to the protein’s short half-life. This necessitates continuous administration requested 24 hours injection throughout the treatment course. Additionally, the drug’s association with the induction of cytokine release syndrome (CRS), presumably linked to the hyperactivation of the cytokine network, presents a significant concern. To address these limitations, we leverage mRNA modality to develop innovative therapeutic mRNAs encoding CD19/CD3 TCE. These mRNA drugs hold the potential to improve protein exposure in vivo with a steady production of encoded protein in-situ. On the other hand, with the gradual expression of protein, mRNA shifted the transient, “pulse”-like pharmacokinetic (PK) feature of the protein drugs to a more “plateau”PK curve, which allows a natural priming of T cells to reduce the risk of CRS induction. In this work, we developed a series of mRNAs encoding CD19/CD3 TCE through our mRNA technology platform and LNP delivery platform. Comparative analyses demonstrated that the TCEs produced in vivo by these mRNAs match the structure and function of recombinantly expressed proteins. PK studies in both mice and non-human primates confirmed a favorable PK profile with over 10-fold increase in TCE exposure compared to their protein counterparts. This increased exposure correlated with superior antitumor efficacy in both ALL and lymphoma models, evidenced by the potent effects of single mRNA doses compared to multiple doses of protein-based treatments. Meanwhile IL6 cytokines induced in mRNA treated mice were significantly alleviated than those in protein treated animals, indicating a reduced risk of induction of CRS. One candidate mRNA demonstrated an optimal "plateau" pharmacokinetic profile, achieving extensive target cell eradication over 20 days with a single low dose of 0.001 mpk in non-human primates. An investigator-initiated clinical study with mRNA encoding CD19/CD3 TCE is underway in relapsed and/or refractory acute lymphoblastic leukemia patients. The preliminary data from the on-going study showed ABO2015 with an acceptable safety profile, and activation of peripheral T cells was observed in one patient with low dose. These findings underscore the significant clinical potential of mRNA-encoded CD19/CD3 TCE in treating B-cell malignancies, heralding a paradigm shift in the clinical application of protein-based T cell engagers. Citation Format: Xia Zhong, Liang Du, Zhenxing Yang, Xiaoli Xu, Jijun Yuan, Bo Ying. Innovative mRNA strategies to encode CD19/CD3 T cell engagers in the treatment of B cell hematological malignancies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6703.

Evaluation of the multiple doses thiozonide’s pharmacokinetics in patients diagnosed with pulmonary tuberculosis with multidrug-resistant or extensively drug-resistant <i>Mycobacterium tuberculosis</i>

Relevance. The increase in the number of cases of multidrug-resistant tuberculosis (MDR-TB) determines the relevance of the development of new anti-TB drugs (ATDs). Determining the pharmacokinetics of a drug in the context of MDR-TB therapy is an integral part of the study of the original drug. Objective. Evaluation of the pharmacokinetic properties of a new original drug, thiozonide, in patients with MDR-TB with multiple doses of the drug. Methods. Thiozonide was used in patients with a verified diagnosis of MDR-TB as part of a clinical trial according to protocol No. THIO22 "Multicenter 12-week doubleblind, randomized, placebo-controlled clinical trial on the selection of optimal dosages of the drug thiozonide, capsules (CJSC Pharm-Sintez") for against the background of standard anti-tuberculosis chemotherapy in patients diagnosed with pulmonary tuberculosis with multidrug-resistant or extensively drugresistant Mycobacterium tuberculosis” (permission of the Ministry of Health of the Russian Federation No. 661 dated 11/24/2014). Results. The pharmacokinetic characteristics of thiozonide were determined during its repeated use in patients diagnosed with pulmonary tuberculosis with multidrug-resistant or extensively drug-resistant mycobacterium tuberculosis, receiving standard anti-tuberculosis chemotherapy, by HPLC with mass spectrometric detection. The time to reach the maximum concentration T max of thiozonide with repeated administration at a dose of 200 mg, 400 mg and 600 mg was 4.21 ± 1.23 hours, 4.9 ± 1.08 and 5.29 ± 0.91, respectively; the half-life T1/2 for the same dosages of the drug was 7.84 ± 1.86, 7.56 ± 1.92 and 6.3 ± 2.12 hours, respectively. The maximum concentration of thiozonide after taking the drug thiozoinide by volunteers was Cmax was observed at the level of 1386.89 ± 533.68 ng / ml in the group taking 200 mg of thiozonide per day, 2684.48 ± 712.40 when taking the drug at a dosage of 400 mg and 5558, 99 ± 2143.81 – at a dosage of 600 mg. Conclusion. A linear dependence of the maximum concentration and the area under the pharmacokinetic curve on the dose taken and also the average concentration of thiozonide in the blood plasma of patients with pulmonary tuberculosis with multidrug resistance of the causative agent of the disease was revealed.

Physiologically based pharmacokinetic modeling to predict maternal pharmacokinetics and fetal carbamazepine exposure during pregnancy

Carbamazepine is an antiepileptic drug commonly used in pregnant women, during which the physiological changes may affect its efficacy. The aim of this study was to establish a physiologically based pharmacokinetic (PBPK) model of carbamazepine and its active metabolite carbamazepine-10,11-epoxide, and simulate maternal and fetal pharmacokinetic changes of carbamazepine and carbamazepine-10,11-epoxide in different trimesters and propose dose adjustment. We established pregnancy PBPK models for carbamazepine and carbamazepine-10,11-epoxide in PK-Sim® and Mobi® and validated the models with observed data from clinical reports. The placental transfer parameters obtained using different methods were also imported into the model and compared with the observed data to establish and validate fetal pharmacokinetic curves. The simulated results showed that mean steady-state trough plasma concentration of carbamazepine decreased by 27, 43.1, and 52 % during the first, second, and third trimesters, respectively. Therefore, to achieve an optimum therapeutic concentration, administering at least 1.4, 1.8, and 2.1 times the baseline dose of carbamazepine in the first, second, and third trimesters, respectively can be used as a dose reference. In conclusion, this study established and validated a pregnancy PBPK model of carbamazepine and carbamazepine-10,11-epoxide to assess exposure in pregnant women and fetuses, which provided a reference for the dosage adjustment of carbamazepine during pregnancy.

An analytical approach for on-site analysis of breath samples for Δ9-tetrahydrocannabinol (THC).

Increased acceptance of cannabis containing the psychoactive component, Δ9-tetrahydrocannabinol (THC), raises concerns about the potential for impaired drivers and increased highway accidents. In contrast to the "breathalyzer" test, which is generally accepted for determining the alcohol level in a driver, there is no currently accepted roadside test for THC in a motorist. There is a need for an easily collectible biological sample from a potentially impaired driver coupled with an accurate on-site test to measure the presence and quantity of THC in a driver. A novel breath collection device is described, which includes three separate sample collectors for collecting identical A, B, and C breath samples from a subject. A simple one-step ethanol extraction of the "A" breath collector sample can be analyzed by UHPLC/selected ion monitoring (SIM) liquid chromatography/mass spectrometry (LC/MS) to provide qualitative and quantitative determination of THC in breath sample in less than 4 min for samples collected up to 6 h after smoking a cannabis cigarette. SIM LC/MS bioanalyses employed d3-THC as the stable isotope internal standard fortified in negative control breath samples for quantitation including replicates of six calibrator standards and three quality control (QC) samples. Subsequent confirmation of the same breath sample in the B collectors was then confirmed by a reference lab by LC/MS/MS analysis. Fit-for-purpose bioanalytical validation consistent with pharmaceutical regulated bioanalyses produced pharmacokinetic (PK) curves for the two volunteer cannabis smokers. These results produced PK curves, which showed a rapid increase of THC in the breath of the subjects in the first hour followed by reduced THC levels in the later time points. A simpler single-point calibration curve procedure with calibrators and QC prepared in ethanol provided similar results. Limitations to this approach include the higher cost and operator skill sets for the instrumentation employed and the inability to actually determine driver impairment.

La dosimetrie du 177Lu-PSMA

New metabolic internal radiotherapy treatments, such as 177Lu-PSMA, as well as compliance with regulatory requirements will ultimately lead to the systematic implementation of personalized dosimetry to estimate the absorbed dose to the organs at risk and to the tumors targeted by the treatment. However, several steps are essential before getting started. In this article, we propose to detail them based on our personal experience and data from the literature, highlighting the difficulties relating to their realization. The first of these steps, often minimized, concerns the implementation of all the elements (settings, determination of correction and conversion factors) required to obtain images suitable for quantification on a conventional SPECT-CT camera. We will then detail the difficulties involved in delineating the volumes of the organs and tumors studied, obtaining their pharmacokinetic curves, to finally finish with the determination of the absorbed dose and discuss its limits.

SAT235 An Orally Administered Robotic Pill (RP) Reliably And Safely Delivers the Human Parathyroid Hormone Analog hPTH(1-34) (Teriparatide) With High Bioavailability in Healthy Human Volunteers: A Phase 1 Study

Abstract Disclosure: J.T. Myers: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. A. Dasari: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. A. Battiwala: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. N. Patel: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. A. Toledo Vo: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. A. Yamaguchi: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. K. Horlen: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. L.C. Fung: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. B. Syed: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. S. Nguyen: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. J. Van Dam: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. M. Imran: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. M. Hashim: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. A.K. Dhalla: Employee; Self; Rani Therapeutics. Stock Owner; Self; Rani Therapeutics. Background/Purpose: Teriparatide, an effective osteoanabolic agent, requires a chronic regimen of daily subcutaneous (SC) injections, representing a burden for patients which may interfere with compliance and quality of life. We have developed a novel oral robotic pill (RP) to deliver biotherapeutic agents with bioavailability rivaling or surpassing that of parenteral injections. Here we present data from a Phase 1 study in healthy women volunteers designed to evaluate the safety, tolerability, and pharmacokinetics (PK) of 20- and 80 µg of hPTH (1-34) administered orally via RP (RT-102) at single doses. Methods: The study was approved by the Alfred Health HREC in Australia. Participants received a single dose of either RT-102 at 20 µg (RT-102/20 µg group; N=15) or 80 µg (RT-102/80 µg group; N=14) or a single 20 µg dose of the commercially available teriparatide (Forteo®) via SC injection (SC group; N=10). Fluoroscopic images were taken to track the transit/deployment of RT-102 and confirm excretion of remnants. Drug concentration in serum samples serially collected over 6 hours were measured by a validated ELISA assay. Results: All 29 participants in the RT-102 arms were able to swallow RT-102 and none experienced any adverse events (AEs) upon device deployment. Both doses of RT-102 were safe and well-tolerated with no serious adverse events (SAEs) reported. In the SC group, a total of six drug-related AEs were reported in four participants. There were no AEs reported in the RT-102/20 µg group. Mild and transient AEs attributed to the drug were observed in one participant in the RT-102/80 µg group. No AEs related to the RP were reported. Imaging confirmed excretion of all RP device remnants within an average of 2.7 ± 1.4 days. Based on serum analyses, drug was successfully delivered by RT-102 in 12 of 15 participants in the 20 µg group and in all 14 participants in the 80 µg group. PK analyses indicated that RT-102 delivered drug with more sustained peak concentrations than the SC group. The Cmax of RT-102 was 98 ± 10 pg/mL for the 20 µg dose and 971 ± 223 pg/mL for the 80µg dose compared to 128 ± 20 pg/mL for the 20 µg SC injection group. The Tmax for RT-102 delivery was 68 and 60 min for the 20 µg and 80 µg doses, respectively, compared to 13 min for the SC injection. Based on AUC calculations of the PK curves, the relative bioavailability of RT-102 dose groups was 3- to 4-fold higher compared to the SC injection group. Conclusions: This study provides the first clinical evidence of safe and successful delivery of hPTH (1-34) via an orally administered RP with high reliability and bioavailability. These data suggest that RT-102 can potentially offer an easier and more convenient treatment option to osteoporosis patients, and given the high bioavailability, RT-102 may be effective at doses lower than the currently approved 20 µg SC dose of teriparatide. Presentation: Saturday, June 17, 2023

Pharmacokinetic and pharmacodynamic bioequivalence of Gan & Lee insulin analogues aspart (rapilin®), lispro (prandilin®) and glargine (basalin®) with EU- und US-sourced reference insulins.

For the successful approval and clinical prescription of insulin biosimilars, it is essential to show pharmacokinetic (PK) and pharmacodynamic (PD) bioequivalence to the respective reference products sourced from the European Union and the United States. Three phase 1, randomized, double-blind, three-period crossover trials compared single doses of the proposed biosimilar insulin analogues aspart (GL-Asp, n = 36), lispro (GL-Lis, n = 38) and glargine (GL-Gla, n = 113), all manufactured by Gan & Lee pharmaceuticals, to the respective EU- and US-reference products in healthy male participants (GL-Asp and GL-Lis) or people with type 1 diabetes (GL-Gla). Study participants received 0.2 U/kg (aspart and lispro) or 0.5 U/kg (glargine) of each treatment under automated euglycaemic clamp conditions. The clamp duration was 12 h (aspart and lispro) or 30 h (glargine). Primary PK endpoints were the total area under the PK curves (AUCins.total ) and maximum insulin concentrations (Cins.max ). Primary PD endpoints were the total area under the glucose infusion rate curve (AUCGIR.total ) and maximum glucose infusion rate (GIRmax ). Bioequivalence to both EU- and US-reference products were shown for all three GL insulins. Least squares mean ratios for the primary PK/PD endpoints were close to 100%, and both 90% and 95% confidence intervals were within 80%-125% in all three studies. There were no noticeable differences in the safety profiles between test and reference insulins, and no serious adverse events were reported for the GL insulins. GL-Asp, GL-Lis and GL-Gla are bioequivalent to their EU- and US-reference products.

Comparison of two different integrated method of pharmacokinetics by the integrated pharmacokinetic research of fangji huangqi decoction

Traditional Chinese medicine (TCM) is characterized by its multiple components. The utilization of mathematical statistical methods to integrate the pharmacokinetics of monomer components can provide a comprehensive understanding of the holistic pharmacokinetic process of TCM. Two distinct integrated methods, namely the correlation coefficient method and the AUC-based weight coefficient method, were employed in this study to elucidate and compare their differences in the integrated pharmacokinetic research of Fangji Huangqi decoction (FHD). FHD is commonly used in clinical practice to treat the nephrotic syndrome. Firstly, one-dose FHD was given to doxorubicin-induced nephropathy (DN) rats, and the prototype compounds of FHD and their metabolites in plasma were qualitatively and semi-quantitatively analyzed by UHPLC-MS/MS. Secondly, the efficacy of FHD was quantitatively characterized by the relative distance method based on metabolomics. The correlation coefficients were obtained by analyzing the correlation between efficacy (relative distance values) and the content of compound, and they were subsequently used for the model integration (correlation coefficient method). Thirdly, the effective compounds of FHD treating DN were screened by integrating network pharmacology and molecular docking, and they were used for another integrated pharmacokinetic model by AUD-based weight coefficient method. Finally, the 2 integrated methods and the 2 integrated pharmacokinetic models were compared. In this study, 30 prototype compounds and 41 metabolites of FHD in plasma were identified, and the pharmacokinetic curve of 18 prototype compounds were built. The efficacy of FHD in the treatment of DN has been relatively quantitation. The 2 established integrated pharmacokinetic models of FHD indicated that the correlation coefficient method was the optimal approach for conducting the integrated pharmacokinetic research on the TCM with unknown effective compounds, whereas the AUC-based coefficient method was suitable for the TCM with the clear effective compounds. The integrated pharmacokinetic models indicated that FHD had high bioavailability and an absorption peak at about 6 h after administration, indicating that the 6 h after administration was the critical period of FHD treating DN. This research would be helpful for the pharmacological and pharmacokinetic research of FHD, and provide a method reference for the integrated pharmacokinetic research of TCM.

Bioequivalence study of generic nirmatrelvir in healthy volunteers

Nirmatrelvir is an antiviral drug that, in combination with ritonavir, is an effective agent for the etiotropic therapy of patients with mild to moderate COVID-19.The aim of the study was to evaluate bioequivalence of the generic drug nirmatrelvir Аrpaxel in combination with ritonavir and the original drug Paxlovid, which is a combination of nirmatrelvir/ritonavir, in a single dose administration to healthy volunteers.Materials and methods. This research was an open-label, randomized, two-period crossover bioequivalence study. It included 2 periods, in each of which the volunteers received either a test drug (nirmatrelvir at the dose of 300 mg) in combination with ritonavir (100 mg), or a reference drug (a combination of nirmatrelvir 300 mg and ritonavir 100 mg), given as a single dose. A wash-out period between each of the administrations was 7 days. The blood sampling to determine the concentration of nirmatrelvir was carried out in the range from 0 to 36 h in each of the study periods. A nirmatrelvir concentration was determined by a validated HPLC-MS/MS method with a lower quantitation limit of 10 ng/mL. Bioequivalence was assessed by comparing 90% confidence intervals (CIs) for the ratio of geometric means of AUC(0–16) and Cmax of the test drug and reference drugs with the established equivalence limits of 80.00–125.00%.Results. In the study were included 68 healthy volunteers, 67 participants of which were included in the bioequivalence population. The pharmacokinetic parameters of the drugs were comparable to each other. The 90% confidence interval for the ratio of the geometric mean of the maximum drug concentration in the blood plasma and the area under the pharmacokinetic curve «concentration-time» from zero to the last blood draw within 36 hours of nirmatrelvir was 87.26–100.83 and 93.27–103.74%, which meets the criteria for assessing bioequivalence. The test drugs were well tolerated by the volunteers. The incidence of adverse events was similar for the test and reference drugs. No serious adverse events were recorded during the entire study.Conclusion. As a result of this study, bioequivalence of the test and reference drugs has been established.

Population Pharmacokinetics and Dose Evaluation of Cycloserine among Patients with Multidrug-Resistant Tuberculosis under Standardized Treatment Regimens.

Although cycloserine is a recommended drug for the treatment of multidrug-resistant tuberculosis (MDR-TB) according to World Health Organization (WHO), few studies have reported on pharmacokinetics (PK) and/or pharmacodynamics (PD) data of cycloserine in patients with standardized MDR-TB treatment. This study aimed to estimate the population PK parameters for cycloserine and to identify clinically relevant PK/PD thresholds, as well as to evaluate the current recommended dosage. Data from a large cohort with full PK curves was used to develop a population PK model. This model was used to estimate drug exposure in patients with MDR-TB from a multicentre prospective study in China. The classification and regression tree was used to identify the clinically relevant PK/PD thresholds. Probability of target attainment was analyzed to evaluate the currently recommended dosing strategy. Cycloserine was best described by a two-compartment disposition model. A percentage of time concentration above MICs (T>MIC) of 30% and a ratio of area under drug concentration-time curve (AUC0-24h) over MIC of 36 were the valid predictors for 6-month sputum culture conversion and final treatment outcome. Simulations showed that with WHO-recommended doses (500 mg and 750 mg for patients weighing <45 kg and ≥45 kg), the probability of target attainment exceeded 90% at MIC ≤16 mg/L in MGIT for both T>MIC of 30% and AUC0-24h/MIC of 36. New clinically relevant PK/PD thresholds for cycloserine were identified in patients with standardized MDR-TB treatment. WHO-recommended doses were considered adequate for the MGIT MIC distribution in our cohort of Chinese patients with MDR-TB.