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Nipocalimab Phase 3 Dose Selection for Severe Hemolytic Disease of the Fetus and Newborn.

Nipocalimab, a neonatal Fc receptor (FcRn) blocker, is under evaluation for severe hemolytic disease of the fetus and newborn (HDFN). In the Phase 2 UNITY trial, weekly intravenous antenatal treatment with nipocalimab at dose regimens of 30 and 45 mg/kg prevented fetal anemia requiring intrauterine transfusion (IUT) in 54% of high-risk pregnancies and delayed the need for IUTs versus their previous pregnancies in the remaining 46% of pregnancies. This analysis aimed to select a weekly dose regimen of nipocalimab for the Phase 3 study in severe HDFN (NCT05912517) that maintains FcRn blockade throughout antenatal treatment, including with an unplanned dosing delay of up to 3 days. Observed pharmacokinetic/pharmacodynamic (PK/PD) data from UNITY (i.e., nipocalimab concentrations, FcRn occupancy, and serum IgG) were analyzed using a model-based approach. A PK/PD model originally developed in nonpregnant participants was updated to incorporate gestational weight gain. Nipocalimab PK and FcRn occupancy were described by a two-compartment model with nonlinear, dose-dependent PK, which captured longitudinal PK, FcRn occupancy, and IgG profiles during dosing and return toward baseline postpartum after discontinuation. Both 30 and 45 mg/kg achieved ∼80%-85% reductions in maternal IgG; however, 30 mg/kg showed greater variability in predose trough concentrations, increasing the risk of falling below concentrations required for full FcRn occupancy across antenatal treatment. Simulations incorporating PK/PD variability indicated that 45 mg/kg weekly per current weight maintained full FcRn occupancy in >95% of pregnant individuals, even with dosing delays up to 3 days. Exploratory exposure-response analyses supported 45 mg/kg for the Phase 3 HDFN study.

Humans

Pharmacokinetic and Pharmacodynamic Bio-Similarity of ADL-018 to Innovator Omalizumab: A Randomized Study in Healthy Adults.

Bioequivalence and safety of ADL-018, an omalizumab biosimilar, were compared with United States-licensed omalizumab (US-OMA) and European Union-approved omalizumab (EU-OMA), both approved for allergies. Healthy adults were randomized (1:1:1) to receive a dose of ADL-018, US-OMA, or EU-OMA (150 mg/mL). Pharmacokinetic (PK) parameters, including AUC(0-last), AUC(0-∞), and Cmax, were considered equivalent if 90% CIs of geometric mean ratios (GMRs) were within predefined equivalence margin (0.80-1.25) using ANCOVA model. Other PK parameters, pharmacodynamics (PD) (free/total immunoglobulin E [IgE]), immunogenicity, and safety were compared. Overall, 306 participants (n = 102 per arm) were dosed; 287 completed the study. Equivalence of primary PK parameters was confirmed for pairwise comparisons, with 90% CIs within the predefined margin (GMRs of ADL-018 vs US-OMA: AUC(0-last)-1.08, AUC(0-∞)-1.07, Cmax-1.05; GMRs of ADL-018 vs EU-OMA: AUC(0-last)-1.06, AUC(0-∞)-1.06, Cmax - 1.05; and GMRs of US-OMA vs EU-OMA: AUC(0-last)-0.99, AUC(0-∞)-0.99, Cmax-1.00). PK/PD parameters were comparable across arms. Increase in total IgE (AUEC ∼30,000 to 35,000 h IU/mL) and decrease in free IgE (AUEC ∼29,000 to 35,000 h IU/mL) were comparable across arms. Similar incidence of adverse events across arms (treatment-emergent adverse events: ADL-018, n = 6; US-OMA, n = 5; EU-OMA, n = 4) was observed. ADL-018 demonstrated PK/PD equivalence and comparable safety profile to reference omalizumab.

Humans

A First-in-Japanese Phase 1, Double-Blind, Placebo-Controlled, Parallel-Cohort Study of Sefaxersen, an Antisense Oligonucleotide Targeting Complement Factor B, in Healthy Participants.

Increased activity in the complement alternative pathway (AP) plays a key role in diseases such as IgA nephropathy (IgAN). This first-in-Japanese double-blind Phase 1 study investigated the pharmacokinetics (PK), pharmacodynamics (PD), safety, and tolerability of sefaxersen (RO7434656), an antisense oligonucleotide targeting complement factor B messenger RNA. Healthy participants were randomized equally into four cohorts: placebo or sefaxersen 20, 40, or 70 mg. The PK, PD, and safety endpoints were monitored throughout the study and during the 90-day follow-up period. All 24 participants completed the study, with no new safety signals or clinically meaningful changes in blood chemistry, electrocardiogram, or vital signs observed. Plasma sefaxersen concentration demonstrated a biphasic PK profile, characterized by an initial rapid decline followed by a slow elimination. Sefaxersen decreased PD markers related to the complement AP selectively, without affecting the classical pathway, in a dose-dependent manner, and the PD effects persisted over 2 to 3 months. Sefaxersen was well tolerated by healthy Japanese participants, with a manageable safety profile. These findings support the inclusion of Japanese patients with IgAN in the global Phase 3 study (IMAGINATION, NCT05797610).

Humans

Validated UPLC-MS/MS quantification and intracellular PK-PD Modeling of periplocin-related cardiac glycosides in H/R-injured H9c2 cells.

Reliable intracellular quantification is essential for characterizing the target-site disposition and exposure-response relationships of bioactive natural products. In this study, an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the simultaneous determination of periplocin and four related cardiac glycoside metabolites in H9c2 cell lysates. Acceptable linearity, precision, recovery, and stability were achieved for intracellular quantification. Cells were treated with each compound at 50 μM, and intracellular concentrations and cell viability were monitored over 48 h. In hypoxia/reoxygenation (H/R) -injured cells, the time to maximum intracellular concentration was shortened for all five compounds, indicating altered cellular disposition under injury conditions. Cell viability was improved by all compounds during the observation period. Pharmacokinetic-pharmacodynamic (PK-PD) integration was performed using a sigmoid Emax model, and acceptable model fits were obtained, with Akaike information criterion (AIC) values ranging from 79.22 to 130.46. Low apparent EC50 values were estimated under this single-dose design, whereas the estimated Ke0 values suggested delayed equilibration with the effect compartment. These findings indicate that sustained cytoprotective responses can be produced by periplocin and related metabolic markers in injured cardiomyocytes. This intracellular bioanalytical strategy provides a quantitative approach for linking cellular exposure to pharmacodynamic response and may support further evaluation of periplocin-related cardiac glycosides.

Tandem Mass Spectrometry

Safety, tolerability, pharmacokinetics, and pharmacodynamics of oral JMKX003002 in Chinese healthy participants: a randomized, double-blind, placebo-controlled, single- and multiple-ascending dose, and food-effect phase I clinical trial.

OBJECTIVE: To evaluate the safety, tolerability, pharmacokinetics (PK), and pharma-codynamics (PD) of the sodium-hydrogen exchanger 3 (NHE3) inhibitor JMKX003002 in Chinese healthy participants. PATIENTS AND METHODS: This phase I, randomized, double-blind, placebo-controlled study included a single-ascending dose (SAD) study with seven cohorts (1 mg [n = 4] and 5, 20, 50, 75, 100, or 125 mg [n = 8]), a food-effect (FE) study with six sequence groups (25 mg twice daily, n = 4), and a multiple-ascending dose (MAD) study with two cohorts (10 mg or 20 mg twice daily, n = 10). RESULTS: JMKX003002 was well-tolerated, with mostly mild treatment-related adverse events. One Grade 3 diarrhoea occurred in each of the 50 mg and 125 mg groups. No serious adverse events were reported, and no participants discontinued or withdrew due to treatment-emergent adverse events. Most plasma samples were below the limit of quantification (0.2 ng/mL), with only transient detection of low concentrations, indicating low systemic exposure. JMKX003002 was primarily excreted in stool (79.9% recovered) and was undetectable in urine. The PD results consistently showed decreased urinary sodium and phosphorus, along with increased stool sodium and phosphorus, compared to baseline across all three studies. One day after discontinuation, stool sodium and phosphorus remained elevated relative to baseline in the MAD study. Mixed-effects model analysis in the FE study demonstrated significant food effect on stool sodium and phosphorus excretion. CONCLUSION: JMKX003002 exhibited favorable safety and tolerability with minimal systemic exposure. It effectively increased sodium and phosphorus excretion in stool. These promising findings warrant further investigation of JMKX003002 to evaluate its clinical benefits. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2300070473). Registered on April 13, 2023; prospectively registered.

Adult

Safety, pharmacokinetics and pharmacodynamics of TQC3721, an innovative, dual PDE3 and PDE4 inhibitor, in healthy subjects and patients with chronic obstructive pulmonary disease: Randomised, double-blind, placebo-controlled phase I and IIa clinical trials.

BACKGROUND AND PURPOSE: TQC3721 is a novel inhaled dual phosphodiesterase (PDE3/4) inhibitor designed to provide bronchodilation and anti-inflammatory effects for chronic obstructive pulmonary disease (COPD). EXPERIMENTAL APPROACH: First-in-human randomised, double-blind, placebo-controlled phase I (SAD: 0.2 to 24 mg single dose; MAD: 12 mg once daily (QD) for 7 days in healthy subjects) and phase IIa studies (0.75 to 6 mg once or twice daily for 4 weeks in moderate-to-severe patients with COPD) were conducted. Primary outcomes included safety, pharmacokinetics (PKs) and pharmacodynamics (PDs), change from baseline of forced expiratory volume in the first second [FEV1], and FEV1 at 12 and 24 h post-dose on days 1 and 28. KEY RESULTS: TQC3721 was rapidly absorbed (median Tmax of 0.25 to 0.5 h), mainly by pulmonary absorption rather than gastrointestinal absorption, along with low systemic exposure and lack of significant accumulation. TQC3721 demonstrated favourable safety profiles in healthy subjects and patients with COPD. In patients with COPD, TQC3721 produced rapid and outstanding bronchodilation effect sustained over 12 h post-administration, with FEV1 peaking at approximately 2 h post-dose and returning to baseline levels by 12 h, which supports a twice-daily dosing regimen for the future, and peak FEV₁ improvements ranging from 186 to 272 ml across dose groups after 4 weeks of treatment. Moreover, twice-daily 3 and 6 mg regimens were recommended for further clinical study. CONCLUSIONS AND IMPLICATIONS: Pharmacokinetic features, significant bronchodilation effects and overall favourable safety characteristics support further clinical development of TQC3721 as a potential dual-mechanism therapy for COPD.

Adult

Phase 1 Study Evaluating Gefurulimab Pharmacokinetics and Safety Following Delivery Via Autoinjector or Prefilled Syringe With Needle Safety Device in Healthy Adults.

PURPOSE: Gefurulimab, a novel dual-binding nanobody targeting complement component 5 (C5), is in clinical development for anti-acetylcholine receptor antibody-positive generalized myasthenia gravis. Gefurulimab has a low molecular weight, enabling subcutaneous (SC) self-administration by autoinjector (AI) or prefilled syringe with needle safety device (PFS-SD). We compared gefurulimab pharmacokinetic (PK) exposure and safety in healthy adults following a single SC dose administered by AI versus PFS-SD. METHODS: In this phase 1, open-label, randomized, parallel-group study (NCT06208488), healthy participants aged 18 to 65 years were stratified by weight and randomized equally to 1 of 6 combination groups of device and injection site (abdomen/thigh/upper arm). Participants received a single SC dose of gefurulimab on day 1 and were assessed throughout the 92-day evaluation period. Primary endpoints were PK parameters for each device: maximum observed concentration (Cmax) and area under the serum concentration-time curve (AUCinf, AUClast). PK across injection sites, pharmacodynamics, safety, immunogenicity, and device performance were also assessed. FINDINGS: Overall, 175 participants were randomized: AI (n = 87), PFS-SD (n = 88). Geometric least squares mean ratios (90% CI) comparing AI/PFS-SD for Cmax, AUCinf, and AUClast were 97.6% (94.5-100.8), 99.6% (96.1-103.3), and 98.8% (95.2‒102.6), respectively. Secondary analyses found no meaningful differences in PK parameters across injection sites. Serum-free C5 concentrations over time, treatment-emergent adverse event (TEAE) profiles, and antidrug antibody responses were similar between cohorts. Most TEAEs were mild; none led to study discontinuation. IMPLICATIONS: SC administration of gefurulimab by AI and PFS-SD was well tolerated with comparable exposure, meeting bioequivalence criteria.

Humans

Safety, Pharmacokinetics, and Pharmacodynamics of Single-Dose Programmed Cell Death Protein 1 Inhibitor, Budigalimab, in People With HIV-1 With Antiretroviral Therapy-Suppressed Viral Load.

BACKGROUND: Blockade of inhibitory immune checkpoint receptor programmed cell death protein 1 (PD-1) on target immune cells is associated with improved HIV-specific immune function and activation of latent HIV. This randomized, placebo-controlled, Phase 1b study assessed low doses of investigational anti-PD-1 monoclonal antibody, budigalimab, for safety, tolerability, pharmacokinetics, and pharmacodynamics in people with HIV (PWH) on antiretroviral therapy. METHODS: Participants received single doses of budigalimab 10 mg subcutaneous (SC), 20 mg SC, 10 mg intravenous (IV), or placebo (n = 8 per arm) and were followed for 24 weeks. RESULTS: Of 32 randomized participants, 22 reported adverse event(s) (AE); most (n = 19) were grade ≤2 and no grade ≥4 AE or treatment-related serious AE. Two participants reported a non-treatment-related grade 3 AE (placebo, n = 1 pneumonia; 10 mg IV, n = 1 elevated aspartate aminotransferase). One reversible immune-related AE (grade 2 lichenoid keratosis) was reported (20 mg SC). Geometric mean maximum serum concentrations were 0.37, 1.57, and 3.2 µg/mL with 10 mg SC, 20 mg SC, and 10 mg IV, respectively. Drug exposure with 20 versus 10 mg SC dosing was more than dose proportional and less variable. Subcutaneous bioavailability was approximately 53%-62%. The PD-1 receptor saturation was ≥95% in most participants (median duration: 20 mg SC, 42 days; 10 mg SC, 14 days; 10 mg IV, 35 days). CONCLUSIONS: Findings suggest an acceptable safety profile for single-dose budigalimab in PWH, with a favorable pharmacokinetic profile for 20 mg SC and 10 mg IV. Further evaluation as a potential component of an HIV treatment is underway.

Humans

A phase I clinical study of the safety, tolerability, pharmacokinetics and pharmacodynamics of SHR-2106, an anti-CD40 antibody, following single intravenous or subcutaneous administration in healthy participants.

BACKGROUND: SHR-2106 is a humanized IgG1 monoclonal antibody that blocks CD40-CD40L interactions and has demonstrated immunosuppressive activity and graft-prolonging effects in preclinical studies. This first-in-human Phase I study evaluated the safety, pharmacokinetics, pharmacodynamics, and immunogenicity of single intravenous or subcutaneous doses of SHR-2106 in healthy adults. METHODS: This randomized, double-blind, placebo-controlled Phase I study enrolled healthy participants. Fifty-one participants were enrolled in seven cohorts and received five intravenous doses (50-1200 mg) or two subcutaneous doses (300 and 600 mg). Safety, serum pharmacokinetics, CD40 occupancy on B cells, and anti-drug antibodies were assessed using standard clinical and bioanalytical methods. RESULTS: SHR-2106 demonstrated a favorable safety and tolerability profile, and most treatment-emergent adverse events were mild to moderate laboratory abnormalities with incidence rates comparable to placebo. SHR-2106 exhibited nonlinear pharmacokinetics consistent with target-mediated drug disposition, with a dose-dependent increase in geometric mean terminal half-life following intravenous administration (1.83-10.7 days). Absolute bioavailability after subcutaneous administration was approximately 60%. CD40 occupancy exceeded 80% within 24 h at all doses, with saturation duration increasing from 7 to 70 days across the intravenous dose range and remaining comparable between routes at matched doses. Anti-drug antibody incidence decreased with increasing intravenous dose and did not significantly affect pharmacokinetics or pharmacodynamics. CONCLUSION: SHR-2106 was well tolerated and achieved rapid and sustained CD40 engagement, supporting dose and route selection for Phase II studies.

Humans

A New Highly Concentrated Insulin Aspart AT278 (500 U/mL) Demonstrates Ultra-Rapid Pharmacokinetic and Pharmacodynamic Properties in Type 2 Diabetes Regardless of BMI.

AIMS: To evaluate the pharmacokinetics, pharmacodynamics, and safety of a novel U500 insulin aspart formulation (AT278 [500&#x2009;U/mL]; AT278-U500) compared with standard concentration insulin aspart (InsAsp [100&#x2009;U/mL]; InsAsp-U100) and U500 human regular insulin (HumIns [500&#x2009;IU/mL]; HumIns-U500). MATERIALS AND METHODS: This single-centre, randomised, double-blind crossover 12-h euglycaemic clamp study was conducted in 41 overweight and obese people with type 2 diabetes (BMI 25.0-38.7&#x2009;kg/m2) receiving a single subcutaneous dose (0.5&#x2009;U/kg) of AT278-U500 and InsAsp-U100. HumIns-U500 was consecutively studied open label in a 24-h clamp. RESULTS: AT278-U500 exhibited a significantly faster insulin absorption than InsAsp-U100 and HumIns-U500 (t Early50%Cmax: 9&#x2009;min vs. 35&#x2009;min vs. 55&#x2009;min), leading to a significantly higher glucose-lowering effect within the first hour (AUCGIR,0-60min) compared with both InsAsp-U100 (treatment ratio 2.02 [95% CI 1.64; 2.50]) and HumIns-U500 (3.91 [2.89; 5.27]). When divided by median BMI (29.7&#x2009;kg/m2), AUCGIR,0-60min was significantly higher with AT278-U500 in both the low-BMI and high-BMI subgroup compared to InsAsp-U100. Linear regression showed a significant inverse relationship between BMI and AUCGIR,0-60min for InsAsp-U100 (slope -0.142, p&#x2009;<&#x2009;0.0001), whereas AT278-U500 showed no such relationship. Overall insulin exposure was similar for AT278-U500 and InsAsp-U100, while overall glucose-lowering effect was comparable across all three treatments. CONCLUSIONS: AT278-U500 maintains its ultra-rapid onset characteristics independent of BMI, representing the first ultra-rapid U500 option for prandial dosing in insulin-resistant people with type 2 diabetes requiring high-dose therapy. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT05754424.

Humans

Clinical pharmacokinetics of afatinib: A systematic review.

BACKGROUND: Afatinib is commonly used in the treatment of non-small cell lung cancer (NSCLC). This systematic review summarizes clinical pharmacokinetics (PK) evidence focusing on the effect of disease state and drug interactions on afatinib exposure. METHODS: Google Scholar, Science Direct, PubMed, and the Cochrane library were searched for human studies reporting the clinical PK of afatinib. The search yielded 24 articles that met the predefined inclusion criteria. RESULTS: Afatinib exposure increased slightly more than dose proportionally, with higher doses producing greater AUC0-24 and Cmax values. The apparent oral clearance reported after administration of the oral solution was lower than that observed following tablet administration. The Cmax of afatinib increases by 38.5% after coadministration with ritonavir and exposure decreases 34.3% with rifampicin. The Cmax decreases 31.45% when given with pemetrexed. Both the AUC0-24 and Cmax increase in NSCLC and tumor state. The AUC0-24 of afatinib is 2.61 folds higher following multiple oral doses among patients with solid tumors. Afatinib exposure is 22.1 % higher in renal impaired patients than in healthy controls. In grade 2 diarrhea, the AUC0-24 of afatinib is 83.93% higher as than in grade 0-1 diarrhea in solid tumor patients. CONCLUSION: This systematic review provides an updated synthesis of clinical PK evidence on afatinib. Afatinib exposure is influenced by dose, repeated administration, renal impairment, diarrhea associated toxicity, and P-glycoprotein mediated drug interactions. These findings may support individualized dosing, toxicity-guided dose adjustment, and future development of PK models for afatinib.

Humans

Comparative efficacy and safety of pharmacokinetically guided and body surface area-based 5-fluorouracil dosing in colorectal cancer: a systematic review and meta-analysis.

BACKGROUND: Body surface area (BSA)-based 5-fluorouracil (5-FU) dosing remains the standard in colorectal cancer despite substantial interpatient pharmacokinetic variability, which may lead to underexposure, treatment failure, or severe toxicity. This systematic review and meta-analysis evaluated whether pharmacokinetically guided 5-FU dosing improves efficacy and safety compared with conventional BSA-based dosing. METHODS: PubMed/MEDLINE, Embase, and Scopus databases were searched from inception to the final search date. The search identified 1,802 records: PubMed/MEDLINE, 47; Embase, 118; and Scopus, 1,637 records. Comparative randomized and non-randomized studies evaluating pharmacokinetically guided, area under the curve-guided, or therapeutic drug monitoring-based 5-FU dosing versus BSA-based dosing in colorectal cancer were included. Random-effects models were employed. The risk of bias was assessed using RoB 2 and ROBINS-I, and the certainty of evidence was evaluated using GRADE. RESULTS: Five studies comprising 809 unique patients were included. Across the primary severe-toxicity analysis, the pooled denominator was 1,338 reported observations, including 625 in the PK-guided 5-FU dosing arm and 713 in the BSA-based 5-FU dosing arm, because one study reported severe toxicity by treatment cycle rather than by patient. PK-guided dosing was associated with lower severe or grade&#x2009;&#x2265;&#x2009;3 toxicity (RR 0.50, 95% CI 0.33-0.76; P&#x2009;=&#x2009;0.001; I&#xb2;=79%). PK-guided dosing was also associated with a higher objective response rate (RR 1.50, 95% CI 1.24-1.80; P&#x2009;<&#x2009;0.0001) and disease control rate (RR 1.18, 95% CI 1.07-1.30; P&#x2009;=&#x2009;0.001). Severe diarrhea was reduced (RR 0.33, 95% CI 0.18-0.62; P&#x2009;=&#x2009;0.0006), whereas mucositis, neutropenia/leukopenia, and hand-foot syndrome were not significantly different between dosing strategies. CONCLUSION: PK-guided 5-FU dosing was associated with lower severe toxicity and diarrhea and higher objective response and disease-control rates than conventional BSA-based dosing. However, the evidence was derived from a small and clinically heterogeneous group of studies, and progression-free or overall-survival benefits could not be established. The findings apply predominantly to metastatic colorectal cancer treated with infusional 5-FU within FOLFOX- or FOLFIRI-based regimens. CLINICAL TRIAL REGISTRATION: Not applicable. This study was a systematic review and metaanalysis, and not a clinical trial.

Humans

A prospective pharmacokinetic interaction study between rifampicin and fusidic acid for the treatment of staphylococcal infections.

OBJECTIVE: Fusidic acid with rifampicin is used for the treatment of severe staphylococcal infection, particularly prosthetic joint infections. Previous studies using twice daily fusidic acid showed rifampicin increases fusidic acid clearance, potentially causing sub-therapeutic concentrations. It is uncertain whether this occurs with three-times daily dosing. This study sought to re-evaluate this potential drug-drug interaction. METHODS: In this prospective, open-label drug-drug interaction population pharmacokinetic (PK) study, participants were randomized to receive fusidic acid or rifampicin for 24&#x2005;hours, followed by combination therapy for the duration of treatment. Drug concentration assays used liquid-chromatography mass spectroscopy on dried blood spots. Population PK models were built for fusidic acid, rifampicin and 25-desacetyl rifampicin. RESULTS: Ten participants were recruited. Inter-individual variability for both absorption (98.1%) and clearance (77.8%) were high for fusidic acid. A population pharmacokinetic model for fusidic acid revealed that early autoinhibition dominated over later rifampicin-mediated induction, resulting in a net decrease in fusidic acid clearance. The mean fusidic acid area under the curve during each dosing interval (AUC&#x3c4;) at steady state was 1.76-fold [0.049, 34.918] higher relative to Day 1, despite high uncertainty.Large inter-individual (110%) variability in absorption was observed for rifampicin. There was no apparent effect on rifampicin metabolism by fusidic acid co-administration, however, fusidic acid decreased clearance of 25-desacetyl rifampicin. CONCLUSION: In patients treated with fusidic acid three times daily in combination with rifampicin, autoinhibition potentially counteracted rifampicin induction such that fusidic acid concentrations were not reduced. Rifampicin clearance was not affected by fusidic acid, but 25-desacetyl rifampicin clearance was decreased. There was large inter-individual variability in the observed concentrations and final parameter estimates.

Fusidic Acid

Optimizing Initial Dosing for Tacrolimus and Mycophenolate in Living Donor Liver Transplantation: A Systematic Critical Review.

BACKGROUND: The pharmacokinetics (PK) of immunosuppressive agents in living donor liver transplantation (LDLT) recipients are expected to differ from those in deceased donor liver transplantation (DDLT) recipients because of the smaller initial liver volume transplanted and pathophysiological changes during liver regeneration. Consequently, the hepatic metabolism, CYP enzyme activity, and glucuronidation may be reduced. The PK of tacrolimus (metabolized by CYP3A5) and mycophenolate (metabolized through glucuronidation) are expected to be affected early post-LDLT. However, the initial dosing recommendations for post-LDLT remain unclear. PURPOSE: This study aimed to recommend initial dosing approaches for tacrolimus and mycophenolate in LDLT recipients based on available PK data in humans. METHODS: A PubMed search was conducted in March 2025 to identify studies investigating the PK data of immediate-release tacrolimus and mycophenolate in pediatric or adult LDLT recipients. RESULTS: After screening, 8 and 8 articles on tacrolimus and mycophenolates, respectively, met the review criteria. The current literature suggests that LDLT recipients require lower tacrolimus doses than DDLT recipients, particularly in the early post-transplant period. In addition, CYP3A5 polymorphisms in both donors and recipients contribute to interindividual variability in tacrolimus exposure, further complicating tacrolimus management. Studies on mycophenolate use in LDLT recipients are limited, with insufficient evidence to support dose reduction. CONCLUSIONS: Reducing the initial tacrolimus dose in LDLT recipients by 30%-50% compared with that in DDLT recipients would be reasonable while maintaining the same initial dose of mycophenolate between LDLT and DDLT recipients.

Humans

A Phase I Study Assessing the Safety, Tolerability, and Pharmacokinetics of Yinfenidone: A Novel, Potent Drug for Idiopathic Pulmonary Fibrosis Treatment in Healthy Chinese Subjects.

PURPOSE: Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease with a median survival of only 2-3 years after diagnosis. Yinfenidone (HEC585) possesses the potential to inhibit the proliferation of pulmonary fibroblasts, making it a promising candidate for the treatment of IPF. This study assessed the safety, tolerability, pharmacokinetics, and metabolic profile of Yinfenidone hydrochloride capsule in healthy Chinese subjects. METHODS: This single-center, randomized, double-blind, placebo-controlled, single ascending-dose trial included seven dose groups(20, 50, 100, 200, 400, 600, and 800 mg). Each group enrolled8 healthy subjects: 6 received Yinfenidone hydrochloride capsules and 2 received matching placebo under fasting conditions. Serial pharmacokinetic (PK) blood samples were collected pre-dose and post-dose, liquid chromatography-tandem mass spectrometry was used to analyze the plasma concentrations of Yinfenidone. Additionally, metabolic biotransformation of Yinfenidone in plasma were conducted in the 100 mg dose group. Safety and tolerability endpoints were monitored via physical examinations, vital signs measurements, clinical laboratory tests, 12-lead electrocardiography (ECG), and adverse events (AEs) documentation throughout the trial. FINDINGS: Yinfenidone was rapidly absorbed, with a median maximum plasma concentration (Tmax) of 1.8-3.0 hours, and had a mean half-life (t1/2) ranging from 31.9 to 62.0 hours. Within the 20-100 mg dose range, systemic drug exposure generally increased with ascending dose, above 100 mg, exposure increased less than proportionally to dose. Metabolite profiling in the 100 mg group revealed that the parentcompound predominated in plasma, with metabolic pathways including mono-oxygenation and N-dealkylation. All reported AEswere mild, classified as Common Terminology Criteria for Adverse Events (CTCAE) version 4.03 grade 1. No serious AEs observed; no subject discontinued the trial due to AEs. Single oral doses of 20-800 mg Yinfenidone hydrochloride capsules administered under fasting conditions demonstrated favorable safety and tolerability profiles in healthy Chinese subjects. IMPLICATIONS: Yinfenidone exhibited rapid absorption (median Tmax, 1.8-3.0 hours) and a long terminal t1/2 ranging from 31.9 to 62.0 hours in this single ascending-dose study, indicating that Yinfenidone can be taken once a day in subsequent clinical studies. Yinfenidone mainly exists in human plasma as the original drug and is metabolized through a variety of metabolic pathways. The AEs observed with Yinfenidone in this study, such as diarrhea, nausea, and dizziness, were similar to those reported with pirfenidone. Overall, Yinfenidone demonstrated a favorable safety and tolerability profile in this cohort of healthy subjects.

Adult

Intramuscular patient-derived xenografts achieve high engraftment rates in gastric cancer: implications for pharmacodynamic testing and genomic biomarker discovery.

BACKGROUND: Gastric cancer (GC) exhibits marked inter-patient heterogeneity, limiting empirical chemotherapy efficacy. Patient-derived xenograft (PDX) models preserve the molecular features of parental tumors and can serve as pharmacodynamic surrogates, but conventional subcutaneous PDX suffers from low engraftment rates. This study evaluated an optimized intramuscular PDX platform for individualized drug testing in GC and applied whole exome sequencing (WES) for biomarker identification (Clinical trial registry: ChiCTR-OOC-17012731). MATERIALS AND METHODS: Ninety-eight treatment-naive GC patients were enrolled between April 2018 and December 2020. Fresh tumor tissues were engrafted into NCG mice by intramuscular transplantation. Drug efficacy was evaluated using tumor cell necrosis rate and Ki-67 expression. WES was performed on 32 engrafted tumorgrafts to characterize driver mutations in fast- and slow-growing subgroups. RESULTS: An engraftment rate of 71.7% (43/60) was achieved, substantially exceeding rates reported in prior studies. Clinical characteristics were independent of engraftment success and outgrowth time (all p&#x2009;>&#x2009;0.05). Fast- and slow-growing tumorgrafts diverged in frequently altered genes: KMT2C, APOB, CDK12 and MSH2 predominated in fast-growing grafts, whereas TP53, CHD3 and TET2 were enriched in slow-growing grafts. Slow-growing tumorgrafts correlated with longer progression-free survival (p&#x2009;=&#x2009;0.02). PDX-guided treatment was associated with improved prognosis. CONCLUSIONS: Intramuscular transplantation into NCG mice yields high engraftment rates for GC PDX. PDX-guided chemotherapy selection is associated with favorable outcomes. Driver mutation divergence between fast- and slow-growing tumorgrafts provides candidate prognostic biomarkers.

Animals

Comparative Bioavailability of Trimodal (CTx-1301) Versus Bimodal Dexmethylphenidate Modified-Release Formulations in Adults with Attention-Deficit/Hyperactivity Disorder: A Randomized, Single-Dose, Crossover Study.

BACKGROUND AND OBJECTIVES: Attention-deficit/hyperactivity disorder (ADHD) is a chronic neurodevelopmental disorder that often requires sustained symptom control throughout the day. Although bimodal extended-release dexmethylphenidate (d-MPH XR) formulations provide initial and intermediate drug release, they may not consistently maintain therapeutic exposure into the late afternoon and evening. Trimodal formulations with an additional delayed release component may extend drug exposure later in the day, although this remains to be established. To explore differences in pharmacokinetic (PK) profiles between trimodal (CTx-1301) and bimodal delivery of d-MPH XR, a comparative bioavailability study was conducted at the highest and lowest doses for both formulations. METHODS: In this randomized, 4-period, crossover study, adults with ADHD received single doses of CTx-1301 (50 mg and 6.25 mg) and d-MPH XR (40 mg and 5 mg). Comparative bioavailability was assessed through adjusted geometric mean ratios for exposure parameters (maximum observed plasma concentration [Cmax], area under plasma concentration-time curve to last measurable concentration [AUClast] and extrapolated to infinity [AUC0-inf]), with a prespecified bioequivalence range of 0.80 to 1.25. Secondary endpoints included partial AUCs and safety assessments. RESULTS: The study population (N&#xa0;=&#xa0;45) was predominantly male (88.9%) and White (55.6%), with mean age of 29.6&#xa0;&#xb1;&#xa0;8.01 years. Adjusted geometric mean ratios comparing the primary exposure parameters (Cmax, AUClast, and AUC0-inf) for CTx-1301 versus d-MPH XR were within the bioequivalence range (0.80-1.25) at both the high and low doses. The CTx-1301-to-d-MPH XR partial AUC ratios were within the bioequivalence range from 0 to 9 hours post-dose. At later intervals (AUC9-12 and AUC12-16), adjusted geometric mean ratios exceeded the upper bioequivalence threshold, consistent with the expected contribution of the third medication release component. Dose proportionality was observed between the two CTx-1301 doses and two d-MPH XR formulations. CTx-1301 was generally well tolerated. The most commonly reported adverse events included tachycardia, insomnia, headache, nausea, and euphoric mood. The incidence of treatment-emergent adverse events was numerically lower with CTx-1301 than with d-MPH XR; however, no statistical analysis was performed. CONCLUSIONS: Key exposure parameters including Cmax, AUClast, and AUC0-inf for trimodal CTx-1301 were statistically bioequivalent to bimodal d-MPH XR. Interval&#x2011;specific PK analyses demonstrated higher exposure with CTx&#x2011;1301 during later post-dose intervals (9-16 h), consistent with the formulation's third release component. However, the clinical relevance of these PK differences requires further evaluation. CTx-1301 demonstrated dose proportionality and was well tolerated at high and low doses. REGISTRATION: ClinicalTrials.gov, NCT04138498; 19 September 2019.

Humans

The effect of metformin on the pharmacokinetics of rifampicin, isoniazid, and pyrazinamide in adults with tuberculosis.

Metformin is under investigation as adjunctive host-directed therapy for tuberculosis (TB), which might interact with first-line TB treatment. We used population pharmacokinetic modeling to assess whether metformin alters first-line TB-drug pharmacokinetics in HIV/TB-coinfected adults without diabetes. Rifampicin, isoniazid, and pyrazinamide pharmacokinetics were investigated in participants from a randomized clinical trial of adjunctive metformin (500 mg twice daily to week 12) in adults starting HIV-associated TB treatment. Antiretroviral therapy (ART)-na&#xef;ve participants initiated dolutegravir-based ART within 8 weeks. Intensive and semi-intensive sampling was conducted at week 5; concentration-time data were analyzed using non-linear mixed-effects modeling. Data from 78 individuals (43 receiving metformin, median weight 60.8 kg, 62.8% male, 79.5% on ART) were analyzed. Rifampicin and pyrazinamide were described by one-compartment models with linear elimination; typical clearances were 15.8 L/h (95% CI: 13.5-18.7) and 3.88 L/h (95% CI: 3.54-4.08), respectively. Isoniazid followed a two-compartment model with a mixture model for acetylator status; clearance was 10.5 L/h (95% CI: 9.44-11.9) in slow acetylators and 28.8 L/h (95% CI: 25.6-31.0) in fast/intermediate acetylators. Metformin reduced isoniazid bioavailability by 15.6% (95% CI: 4.45-26.4%, P < 0.009) and rifampicin bioavailability by 24.0% (95% CI: 7.83-36.3%, P < 0.007), decreasing the area under the curve from 0 to 24 h from 18.2 to 15.6 mg&#xb7;h/L and from 35.9 to 27.1 mg&#xb7;h/L, respectively. No significant effect on pyrazinamide was detected. We found that non-diabetic patients on metformin had lower isoniazid and rifampicin bioavailability. Lowered rifampicin exposure might be clinically relevant; simulations suggest that this could be offset by a single 150 mg rifampicin dose.CLINICAL TRIALSThis study is registered with ClinicalTrials.gov as NCT04930744.

Humans