OBJECTIVE: Over the past decade, catfish farming has increased in Southeast Asia. However, there has been no existing for pharmacokinetic data in the hybrid catfish (Clarias macrocephalus x C. gariepinus).
OBJECTIVE: This study was designed to evaluate the pharmacokinetic characteristics of oxytetracycline (OTC) in the hybrid catfish, following single intravascular (IV) or oral (PO) administration at a single dosage of 50 mg/kg body weight (BW).
METHODS: In total, 140 catfish (each about 100-120 g BW) were divided into two groups (n = 70). Blood samples (0.6-0.8 mL) were collected from ventral caudal vein at pre-assigned times up to 144 h (sparse samples design). OTC plasma concentrations were analyzed using high-performance liquid chromatography-photodiode array detector.
RESULTS: The pharmacokinetic parameter of OTC was evaluated using a non-compartment model. OTC plasma concentrations were detectable for up to 144 and 120 h after IV and PO, respectively. The elimination half-life value of OTC was long with slow clearance after IV administration in hybrid catfish. The average maximum concentration value of OTC was 2.72 µg/mL with a time at the maximum concentration of 8 h. The absolute PO bioavailability was low (2.47%).
CONCLUSIONS: These results showed that PO administration of OTC at a dosage of 50 mg/kg BW was unlikely to be effective for clinical use in catfish. The pharmacodynamic properties and clinical efficacy of OTC after multiple medicated feed are warranted.

Cumulative evidence from several pre-clinical studies suggests that restoration of plasma DNase activity in a thrombo-inflammatory state may improve clinical outcomes. Following injury, hyperactivated immune cells release large amounts of granular proteins together with DNA, which often accumulate in the surrounding environment in so-called neutrophil extracellular traps (NETs). Degradation of excess NETs by systemic DNase administration offers a promising therapeutic approach to ameliorate inflammation and dissolve intravascular clots. In order to expand the therapeutic utility of human DNase I, a variant of the enzyme was developed that has both a prolonged systemic half-life and a higher catalytic activity compared to Dornase alfa (Pulmozyme®), the recombinant form of DNase I approved for inhaled therapy of cystic fibrosis. The hyperactive enzyme was \"PASylated\" by genetic fusion with a strongly hydrophilic and biodegradable PAS-polypeptide to increase its hydrodynamic volume and retard kidney filtration. A stable TurboCell™ CHO-K1-based cell line was generated which is suitable for the future production of PASylated DNase I according to good manufacturing practice (GMP). Furthermore, a robust bioprocess strategy was devised and an effective downstream process was developed. The final protein product is characterized by excellent purity, favorable physicochemical properties, a 14-fold higher DNA-degrading activity than Dornase alfa and a sustained pharmacokinetic profile, with a 22-fold slower clearance in rats.

This study aimed to assess the safety, pharmacokinetics, and food impact on sudapyridine (WX-081), a novel drug designed to inhibit mycobacterium ATP synthase, with clinical applications for drug-resistant tuberculosis (TB) treatment. The research comprised two arms: a single ascending dose (SAD) arm (30 to 600 mg, N = 52) and a multiple ascending dose (MAD) arm (200 to 400 mg, N = 30). The influence of food was evaluated using a 400 mg dose within an SAD cohort. Plasma concentrations of WX-081 and M3 (main metabolite of WX-081) were analyzed using a validated liquid-chromatography tandem mass spectrometry method. In the SAD arm, mean residence time (MRT0-t), terminal half-life, and clearance of WX-081 ranged from 18.87 to 52.8 h, 31.39 to 236.57 h, and 6.4 to 80.34 L/h, respectively. The area under the curve from time zero to the last measurable timepoint (AUC0-t) of WX-081 showed dose-proportional increases in the SAD arm. The disparity between fasted and fed states of WX-081 was significant (p < 0.05), with fed dosing resulting in a 984.07% higher AUC0-t and 961.55% higher maximum plasma concentration. In both the SAD and MAD arms, one case each exhibited a 1 degree atrioventricular block. No QTc elongation was observed, and adverse events were not dose-dependent. Favorable exposure, tolerability, safety, and an extended MRT0-t suggest that WX-081 holds promise as a phase II development candidate for drug-resistant TB treatment.

This bioequivalence research aims to evaluate the relative bioavailability and pharmacokinetic characteristics of ethinyl estradiol and drospirenone in the test preparation in comparison to the reference preparation during fasting conditions. A liquid chromatography method with tandem mass spectrometry was used to determine the concentrations of drospirenone and ethinyl estradiol in plasma. The pharmacokinetic parameters that were analyzed were the maximum plasma concentration (Cmax), time to achieve Cmax (tmax), elimination half life, and area under the concentration time curve of plasma (AUC0-t, AUC0-∞ for ethinyl estradiol, and AUC0-72h for drospirenone). Both the AUC and Cmax parameters were determined to be between 80.00% and 125.00% (90% confidence intervals), which is the acceptable range. Based on the study findings, it was concluded that the test formulation, which includes 3 mg of drospirenone and 0.03 mg of ethinyl estradiol, demonstrated bioequivalence when compared to the reference formulation.

Peptide drugs are becoming star drug agents with high efficiency and selectivity which open up new therapeutic avenues for various diseases. However, the sensitivity to hydrolase and the relatively short half-life have severely hindered their development. In this study, a new generation artificial intelligence-based system for accurate prediction of peptide half-life was proposed, which realized the half-life prediction of both natural and modified peptides and successfully bridged the evaluation possibility between two important species (human, mouse) and two organs (blood, intestine). To achieve this, enzymatic cleavage descriptors were integrated with traditional peptide descriptors to construct a better representation. Then, robust models with accurate performance were established by comparing traditional machine learning and transfer learning, systematically. Results indicated that enzymatic cleavage features could certainly enhance model performance. The deep learning model integrating transfer learning significantly improved predictive accuracy, achieving remarkable R2 values: 0.84 for natural peptides and 0.90 for modified peptides in human blood, 0.984 for natural peptides and 0.93 for modified peptides in mouse blood, and 0.94 for modified peptides in mouse intestine on the test set, respectively. These models not only successfully composed the above-mentioned system but also improved by approximately 15% in terms of correlation compared to related works. This study is expected to provide powerful solutions for peptide half-life evaluation and boost peptide drug development.

Insulin icodec is a once-weekly insulin analogue that has a long half-life of approximately 7 days, making it suitable for once weekly dosing. The Insulin icodec molecule was developed based on the hypothesis that lowering insulin receptor affinity and introducing a strong albumin-binding moiety would result in a long insulin half-life, provided that non-receptor-mediated clearance is diminished. Here, we report an insulin clearance mechanism, resulting in the splitting of insulin molecules into its A-chain and B-chain by a thiol-disulphide exchange reaction. Even though the substitutions in insulin icodec significantly stabilise insulin against such degradation, some free B-chain is observed in plasma samples from minipigs and people with type 2 diabetes. In summary, we identify thiol-disulphide exchange reactions to be an important insulin clearance mechanism and find that stabilising insulin icodec towards this reaction significantly contributes to its long pharmacokinetic/pharmacodynamic profile.

The residue characteristics, processing effects of washing and drying, and dietary risks of chlorantraniliprole (CAP) and flubendiamide (FBD) to Koreans were investigated using Aster scaber in a greenhouse. Following foliar application, the initial FBD residues were 3-10 times higher than those of CAP. However, the biological half-lives were similar at 6.0-8.3 and 6.8-9.9 days for CAP and FBD, respectively. The pre-harvest residue limits (PHRLs) 7 days before harvest, derived from the dissipation rates and maximum residue limits, were 12.2 and 33.2 mg/kg for CAP and FBD, respectively. For the removal of CAP and FBD from A. scaber, washing with a neutral detergent was more effective than running under or dipping in tap water (86.5 % and 66.2 %, respectively). Processing factors in fields I and II were 2.6 and 5.1 for CAP and 2.0 and 5.7 for FBD, respectively. Drying removal efficiencies in fields I and II averaged 46.4 % and 52.3 % for CAP and 48.4 % and 49.2 % for FBD, respectively. Chronic health risk assessments indicated that dietary exposure to CAP and FBD is acceptable for Korean health.

This study assessed the pharmacokinetics (PKs) and pharmacodynamics (PDs) of two antihypertensive drugs, nifedipine and captopril, by exploring their main (blood pressure [BP]) and secondary effects (heart rate [HR] and QT interval [QT]) in spontaneously hypertensive rats. This study aimed to assess the relationship between PKs and PDs. Using these PD parameters, BP, HR, and QT during coadministration were estimated. The coadministration of nifedipine and captopril resulted in an increase in nifedipine\'s total body clearance (CLtot) and a reduction in its mean residence time (MRT) with an increase in the terminal elimination half-life (t1/2) and volume of distribution at steady state (Vdss) of captopril. However, no significant PK interactions were observed. During monotherapy, BP reduced rapidly following nifedipine infusion. Subsequently, despite the increase in nifedipine plasma concentration, BP recovered, likely because of homeostasis. Similar results were observed with coadministration. Subsequently, BP demonstrated a sustained reduction that was greater than or equal to the additive effect estimated from each PK. Captopril exhibited a minimal effect on HR, except for a transient increase observed immediately after starting infusion, consistent with observations during coadministration. Subsequently, the HR reduction was nearly equal to that calculated from the nifedipine PK. QT prolongation was more rapid with captopril than with nifedipine. Although QT prolongation during the initial 60 min of coadministration was approximately the sum of both effects, the recovery period to baseline QT was faster than that in the simulation.

Obstructive hypertrophic cardiomyopathy (oHCM) is a subtype of HCM characterized by left ventricular outflow tract obstruction resulting from cardiac muscle hypertrophy and anatomic alterations in the mitral valve and apparatus. Mavacamten, a cardiac myosin inhibitor metabolized primarily by CYP2C19 in the liver, is the first and only targeted medication approved for the treatment of symptomatic New York Heart Association (NYHA) class II-III oHCM. Previous pharmacokinetic (PK) results of mavacamten in healthy Caucasian, Japanese, and Asian participants demonstrated that mavacamten exposure was affected by CYP2C19 metabolism status. This open-label, parallel-group, phase I trial aimed to determine the PK and safety of mavacamten in healthy Chinese participants with different CYP2C19 genotypes. The primary outcome was to define the PK of mavacamten in healthy Chinese participants; the secondary outcome was to examine safety and tolerability. After a single oral dose of 15 or 25 mg mavacamten in fasted healthy adult Chinese individuals, Cmax was reached within a median Tmax of 0.6-1.5 h, indicating rapid absorption. Inter-individual variability was moderate, and individuals carrying non-functional CYP2C19 alleles (*2/*2, *3/*3, or *2/*3) exhibited longer half-life and increased total exposure. After stratification of CYP2C19 genotypes, total mavacamten exposures were similar among different ethnic groups when compared with prior PK studies. No significant adverse events were observed in this study. Single oral administration of mavacamten at 15 mg was well tolerated across all CYP2C19 genotypes, and 25 mg dose was well tolerated in healthy participants with CYP2C19 genotypes UM/RM/NM. The PK profile of mavacamten in the healthy Chinese population was consistent with that in other healthy populations.

OBJECTIVE: Randomised, double-blind, crossover trial to confirm bioequivalence of somapacitan, a long-acting growth hormone (GH), in 5 mg/1.5 mL and 10 mg/1.5 mL strengths in equimolar doses.
METHODS: Healthy participants were randomised (1:1:1) to subcutaneous somapacitan treatment in one dosing period with 5 mg/1.5 mL and two periods with 10 mg/1.5 mL. Eligibility criteria included age 18-45 years and body mass index 18.5-24.9 kg/m2. Exclusion criteria included history of GH deficiency, previous GH treatment, weight > 100.0 kg and participation in any clinical trial of an investigational medicinal product within 45 days or five times the half-life of the previous investigational product before screening. Area under the curve from time 0 until last quantifiable observation (AUC0-t), maximum serum concentration (Cmax), time to Cmax and terminal half-life of somapacitan and safety were assessed.
RESULTS: In total, 33 participants were randomised. For AUC0-t, estimated treatment ratio (ETR) (5 mg/1.5 mL versus 10 mg/1.5 mL) was 0.95 (90% confidence interval [CI] 0.89-1.01). Point estimate and 90% CIs were within the acceptance range (0.80-1.25). For Cmax, ETR was 0.77 (90% CI 0.68-0.89). Point estimate and 90% CIs were outside the acceptance range (0.80-1.25). Mean insulin-like growth factor-I (IGF-I) and IGF-I standard deviation score concentration-time curves for each strength were almost identical. No new safety issues were identified.
CONCLUSIONS: Bioequivalence criterion for somapacitan 5 mg/1.5 mL and 10 mg/1.5 mL was met for AUC0-t but not for Cmax. The two strengths had equivalent IGF-I responses.
BACKGROUND: ClinicalTrials.gov, NCT03905850 (3 April 2019).
Somapacitan is a long-acting growth hormone used to treat people with growth hormone deficiency. Somapacitan is injected under the skin with an injection pen. The dose is based on a person’s body weight and how they respond to treatment. We compared two strengths of injection pen, containing either 5 or 10 mg of somapacitan per 1.5 mL. For both strengths, participants were given the same dose. We wanted to understand whether the body absorbs these different strengths into the bloodstream in the same way. We also measured levels of insulin-like growth factor-I (IGF-I), a hormone formed when growth hormone is present in the blood, to see the effect of different strengths of somapacitan on the body. In our study, 33 healthy adults received one round of injection using the somapacitan 5 mg pen and two rounds using the somapacitan 10 mg pen, all at least 3 weeks apart. We found no differences in the amount of somapacitan being absorbed into the bloodstream, nor how fast it was absorbed. The peak amount of somapacitan in the bloodstream was higher in people using the 10 mg pen. There were no differences in IGF-I levels following use of either injection pen. Overall, our results show both strengths of somapacitan lead to similar responses in the body. Having different strength options could allow doctors to adjust the dose of somapacitan more easily, depending on a patient’s response to treatment.