Development and Validation of a Bioanalytical LC-MS/MS Method for Simultaneous Determination of Sirolimus in Porcine Whole Blood and Lung Tissue and Pharmacokinetic Application with Coronary Stents

Core-shell tablets designed for modified and sequential release of ibuprofen and rabeprazole

In this study, core-shell tablets comprising an ibuprofen (IBU) enteric-coated core for modified release and a rabeprazole (RAB) shell for immediate release were developed using wet granulation method. The primary aim was to produce a sequential release of RAB and IBU with pharmacokinetic profiles comparable to those of the respective single tablets, thereby reducing the potential for IBU-associated gastrointestinal (GI) side effects. The composition of the IBU/RAB core-shell tablets was finalized on a comparative basis by evaluating various trial formulations. IBU/RAB core-shell tablets (400/20 mg) were assessed for physicochemical attributes, storage stability, and in vivo pharmacokinetics in beagle dogs. IBU/RAB core-shell tablets showed immediate RAB release (99.5 % in 1 h at pH 1.2) and delayed IBU release (3.4 % and 88 % in the acid and buffer stages, respectively). IBU/RAB core-shell tablets produced either comparable or improved plasma concentrations in dogs (Cmax; 1163.3 vs. 1160.0 ng/mL for RAB and 27,370 vs. 24,170 ng/mL for IBU) compared to those of the respective single tablets. The IBU/RAB core-shell tablets also demonstrated long-term and accelerated storage stability. In conclusion, the core-shell design could be a promising strategy for the co-administration and sequential release of IBU and RAB to relieve inflammatory conditions and reduce GI complications.

Biochanin-A co-crystal formulation improves bioavailability and ameliorates cerulein-induced pancreatitis by attenuating the inflammation

Co-crystallization of a therapeutic ingredient with an appropriate co-former is a powerful technique to augment the physicochemical and pharmacokinetic properties and the effectiveness of Active Pharmaceutical Ingredients (APIs). Biochanin A (BCA), a flavonoid with medicinal potential, is limited by poor solubility and low oral bioavailability. This study aimed to design and develop a novel BCA-nicotinamide cocrystal as BCC to enhance BCA's oral bioavailability and explore its therapeutic potential for ameliorating cerulein-induced acute pancreatitis (CIAP) by elucidating the target identification utilizing tissue/serum metabolite profiles. The cocrystal was designed by the supramolecular synthon approach and characterized by single-crystal X-ray diffraction that confirms a robust three-dimensional hydrogen-bonded network of BCA and Nicotinamide (NCT) in the crystal. FT-IR and DSC were used to analyze the cocrystal's intermolecular interactions and thermal behavior. BCC exhibited enhanced solubility and drug release compared to BCA alone, resulting in enhanced oral bioavailability and pancreatic tissue concentration. Comparing BCC to BCA in the CIAP model, BCC therapy remarkably reduced cerulein-induced pancreatitis, evidenced by significant reductions in inflammation, acinar cell atrophy, and amylase levels in pancreatic tissues. Further, the cocrystal formulation also down-regulated the oxidative stress markers, inflammatory cytokines and macrophage-related proteins. The study has identified distinct metabolomic signatures linked with AP with the help of Orbitrap Exploris mass spectrometry, which could pave the way for creating focused diagnostic tools for a better prognosis. In conclusion, these results offer new insights into exploring mechanistic pathways associated with specific biomarkers and underscore BCC cocrystals as a promising approach to enhance BCA's therapeutic potential.

Preparation and in vivo and ex vivo studies of sirolimus nano-in-situ gel ophthalmic formulation

Sirolimus (SR) is a macrolide with antifungal and antitumor immunosuppressant properties, classified as a selective inhibitor of mammalian target of rapamycin (mTOR). In this study, an ionic in situ gel of SR (SR-SUS-ISG) was formulated using gellan gum, exhibiting stability regardless of temperature and pH variations, causing minimal irritation. Harnessing the physiological conditions of the eye, SR-SUS-ISG underwent gelation upon contact with ions, increasing drug viscosity and prolonging retention on the ocular surface. Concurrently, SR-SUS-ISG displayed favorable shear dilution properties, reducing viscosity at ambient temperature, enhancing fluidity, and facilitating convenient packaging and transport. Biocompatibility assessments on both human corneal epithelial cells and rabbit eyes demonstrated that SR-SUS-ISG could well be tolerated. Pharmacokinetic investigations in rabbit ocular aqueous humor revealed sustained release, improved corneal penetration, and enhanced bioavailability. Additionally, in a rat corneal alkali burn model, SR-SUS-ISG exhibited inhibitory effects on corneal neovascularization, associated with decreased levels of the inflammatory factors VEGF and MMPs. These findings suggested that SR-SUS-ISG held promise as an effective ocular drug delivery system.

Lung microdialysis and in vivo PK/PD integration of cefquinome against Actinobacillus pleuropneumoniae in a porcine experimental lung infection model

This study aim to explore the application of microdialysis in pharmacokinetic (PK) and pharmacodynamic (PD) integration of cefquinome against Actinobacillus pleuropneumoniae in a porcine experimental lung infection model. The model was established via intratracheal inoculation where average bacterial counts (CFU) in the lungs of infected pigs reached 6.57 log10 CFU/g after 3 h. The PK profiles of unbound cefquinome in lung dialysates were determined following intramuscular injection of single doses of 0.125, 0.25, 0.5, 1, 2, and 4 mg/kg. Lung dialysate samples were collected using microdialysis at a flow rate of 1.5 μL/min until 24 h. The PD studies were conducted over 24 h based on 10 intermittent dosing regimens and total daily doses ranged from 0.25 to 4 mg/kg and dosage intervals included 12 and 24 h. The lung tissue was collected after 24 h of treatment and homogenized for bacterial counts. The relationships between PK/PD parameters derived from lung dialysates and drug efficacy were analyzed using an inhibitory sigmoid Emax model. The percentage of time the free drug concentration exceeded the minimum inhibitory concentration (%fT > MIC) was the PK/PD index best describing the antimicrobial activity (R2 = 0.96) in the porcine experimental infection model. The %fT > MIC values required to achieve net bacterial stasis, 1, 2 and 3 log10 CFU/g reductions in the lung were 22.45, 28.86, 37.62, and 56.46%, respectively. Cefquinome exhibited time-dependent characteristics against A. pleuropneumoniae in vivo. These results provide valuable insights into the application of microdialysis in PK/PD integration model studies and optima regimen of cefquinome for the treatment of porcine respiratory diseases caused by A. pleuropneumoniae.

Determination of five mTOR inhibitors in human plasma for hepatocellular carcinoma treatment using QuEChERS-UHPLC-MS/MS

A fast and reliable QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method for pre-processing combined with Ultra - high performance liquid chromatography - tandem mass spectrometry (UHPLC-MS/MS) was established for the analysis of five mammalian rapamycin target protein (mTOR) inhibitors (vistusertib, AZD8055, pictilisib, everolimus, temsirolimus)in human plasma. Extraction was achieved by addition of acetonitrile to the sample followed by anhydrous magnesium sulfate and 30 mg C18 for salting out and purification, respectively. MTOR inhibitors were detected using selective response monitoring (SRM) under positive ion electrospray mode. Vistusertib, AZD8055 and pictilisib showed good linearity with a range of 1-80 ng/ml, Additionally, the concentration of everolimus and temsirolimus was 2.5-200 ng/ml and10-800 ng/ml, respectively. The linear correlation coefficient (R2) of each analysis was ≥ 0.9950. The limit of detection (LOD) and Limit of Quantitation (LOQ) were 0.015-0.75 ng/ml and 1-10 ng/ml, respectively. This method showed a high accuracy with high recovery rate and excellent stability. This method is fast, accurate and reliable, suitable for quantitative detection of mTOR inhibitors in human plasma.

Progressing nanotechnology to improve targeted cancer treatment: overcoming hurdles in its clinical implementation

The use of nanotechnology has the potential to revolutionize the detection and treatment of cancer. Developments in protein engineering and materials science have led to the emergence of new nanoscale targeting techniques, which offer renewed hope for cancer patients. While several nanocarriers for medicinal purposes have been approved for human trials, only a few have been authorized for clinical use in targeting cancer cells. In this review, we analyze some of the authorized formulations and discuss the challenges of translating findings from the lab to the clinic. This study highlights the various nanocarriers and compounds that can be used for selective tumor targeting and the inherent difficulties in cancer therapy. Nanotechnology provides a promising platform for improving cancer detection and treatment in the future, but further research is needed to overcome the current limitations in clinical translation.

Formulation and Evaluation of a Self-Microemulsifying Drug Delivery System of Raloxifene with Improved Solubility and Oral Bioavailability

Poor aqueous solubility and dissolution limit the oral bioavailability of Biopharmaceutics Classification System (BCS) class II drugs. In this study, we aimed to improve the aqueous solubility and oral bioavailability of raloxifene hydrochloride (RLX), a BCS class II drug, using a self-microemulsifying drug delivery system (SMEDDS). Based on the solubilities of RLX, Capryol 90, Tween 80/Labrasol ALF, and polyethylene glycol 400 (PEG-400) were selected as the oil, surfactant mixture, and cosurfactant, respectively. Pseudo-ternary phase diagrams were constructed to determine the optimal composition (Capryol 90/Tween 80/Labrasol ALF/PEG-400 in 150/478.1/159.4/212.5 volume ratio) for RLX-SMEDDS with a small droplet size (147.1 nm) and stable microemulsification (PDI: 0.227). Differential scanning calorimetry and powder X-ray diffraction of lyophilized RLX-SMEDDS revealed the loss of crystallinity, suggesting a molecularly dissolved or amorphous state of RLX in the SMEDDS formulation. Moreover, RLX-SMEDDS exhibited significantly higher saturation solubility and dissolution rate in water, simulated gastric fluid (pH 1.2), and simulated intestinal fluid (pH 6.8) than RLX powder. Additionally, oral administration of RLX-SMEDDS to female rats resulted in 1.94- and 1.80-fold higher area under the curve and maximum plasma concentration, respectively, than the RLX dispersion. Collectively, our findings suggest SMEDDS is a promising oral formulation to enhance the therapeutic efficacy of RLX.

Monitoring of sirolimus in the whole blood samples from pediatric patients with lymphatic anomalies

In recent years, off-label use of sirolimus (SIR) has been gaining attention in the clinical practice. However, since it is critical to achieve and maintain therapeutic blood levels of SIR during treatment, the regular monitoring of this drug in individual patients must be implemented, especially in off-label indications of this drug. In this article, a fast, simple, and reliable analytical method for determining SIR levels in whole blood samples is proposed. Sample preparation based on dispersive liquid-liquid microextraction (DLLME) followed by liquid chromatography-mass spectrometry (LC-MS/MS) was fully optimized toward the analysis of SIR and proposed as a fast, simple, and reliable analytical method for determining the pharmacokinetic profile of SIR in whole-blood samples. In addition, the practical applicability of the proposed DLLME-LC-MS/MS method was evaluated by analyzing the pharmacokinetic profile of SIR in whole blood samples obtained from two pediatric patients suffering from lymphatic anomalies, receiving this drug as off-label clinical indication. The proposed methodology can be successfully applied in routine clinical practice for the fast and precise assessment of SIR levels in biological samples, thus allowing SIR dosages to be adjusted in real time during pharmacotherapy. Moreover, the measured SIR levels in the patients indicate the need for monitoring between doses to ensure the optimal pharmacotherapy of patients.

Simultaneous Determination of Moxifloxacin Hydrochloride and Dexamethasone Sodium Phosphate in Rabbit Ocular Tissues and Plasma by LC-MS/MS: Application for Pharmacokinetics Studies

Treatment of ocular infection involves pharmacotherapy with steroids and antibiotic drops, such as moxifloxacin hydrochloride (MFH) and dexamethasone sodium phosphate (DSP). To characterize the pharmacokinetics of these two compounds, we performed and validated a liquid chromatography-mass spectrometry (LC-MS/MS) method to quantify them in rabbit ocular tissues and plasma. We used protein precipitation to extract the compounds. The analyte and internal standard (IS) were separated using a Shim-pack Scepter C18 column. The mobile phase was composed of 0.1% formic acid water (A) and methanol (B). MFH and DSP were detected using positive ion electrostatic ionization (ESI) in multiple reaction monitoring mode (MRM). The calibration curves for both compounds showed good linearity over concentrations ranging from 0.5 to 200 ng/mL in rabbit ocular tissues and plasma. The lower limit of quantification for both MFH and DSP was 0.5 ng/mL. We validated this method for selectivity, linearity (r2 > 0.99), precision, accuracy, matrix effects, and stability. Thus, we used this method to assess the pharmacokinetic (PK) characteristics of MFH and DSP in rabbit ocular tissues and plasma after single doses. Our results indicate that this method can be used for the simultaneous analysis of moxifloxacin hydrochloride and dexamethasone sodium phosphate in clinical samples.

Comparison of LC-MS/MS and EMIT methods for the precise determination of blood sirolimus in children with vascular anomalies

Sirolimus (SRL) is a mammalian target of rapamycin (mTOR) inhibitor. The whole blood concentration of SRL is routinely monitored to tailor dosage and prevent toxicity. Currently, the enzyme multiplied immunoassay technique (EMIT) is often applied to perform therapeutic drug monitoring (TDM) of SRL, but the cross-reactivity with various metabolites is of great concern. A more specific method is required, such as liquid chromatography–tandem mass spectrometry (LC-MS/MS). However, no study on the method comparison of the EMIT and LC-MS/MS for the measurement of whole blood SRL concentration in children with vascular anomalies has been reported. This study developed a simple and sensitive LC-MS/MS assay for the determination of SRL. Meanwhile, consistency between LC-MS/MS and the EMIT was evaluated by linear regression and Bland–Altman analysis. Whole blood samples were deproteinized with methanol for erythrocyte lysis, and the resulting solution was injected into the LC-MS/MS system using the positive electrospray ionization mode. The multiple reaction monitoring transitions of m/z 931.7 → 864.6 and m/z 934.7 → 864.6 were used for SRL and SRL-d3 as the internal standards, respectively. The analytes were separated on a C18 column with a gradient mobile phase (0.1 mM formic acid and 0.05 mM ammonium acetate in methanol/ultrapure water). Blood samples collected from children with vascular anomalies undergoing SRL therapy were tested by EMIT and by LC-MS/MS. The linear range of LC-MS/MS was 0.500–50.0 ng/ml and that of the EMIT was 3.50–30.0 ng/ml. A significant positive correlation between the two assays was established with a regression equation described as [EMIT] = 1.281 × [LC−MS/MS] + 2.450 (r = 0.8361). Bland–Altman plots showed a mean concentration overestimation of 4.7 ng/ml [95% CI: (−3.1, 12.6)] and a positive bias of 63.1% [95% CI: (−36.1, 162.3)] generated by the EMIT more than that of by LC-MS/MS. In conclusion, the two methods were closely correlated, indicating that switching between the two methods is feasible. Considering the overestimation nature of the EMIT assay, switching from the EMIT to the LC-MS/MS method deserves close attention and necessary re-evaluation for the target therapeutic reference range, may be required when methods are switched within the same clinical laboratory or results are compared between different laboratories.

Matrix-assisted laser desorption/ionization mass spectrometric imaging the spatial distribution of biodegradable vascular stents using a self-made semi-quantitative target plate

In recent years, the development and optimization of biodegradable coronary stents have become the research focus of many medical device manufacturers and scientific research institutions since they can be completely degraded and absorbed, and they restore vascular function. However, there is a lack of in situ quantification of these stents spatially in tissue in vivo. In this study, matrix-assisted laser desorption/ionization (MALDI) Fourier transform ion cyclotron resonance (FT ICR) and time-of-flight (TOF) mass spectrometric imaging (MSI) were used to analyze the time-dependent distributions of a biodegradable vascular scaffold, which consisted of copolymers of lactic acid and glycolic acid (PLGA) and its degradation products in cross-sections and longitudinal sections of blood vessels. The MALDI-MSI methods for analyzing the distribution of PLGA and its derivatives in vivo were established by optimizing the conditions of sample pretreatment and mass spectrometry (MS). In order to semi-quantify the contents of PLGA degradation products in blood vessels, self-made stainless-steel and indium tin oxide (ITO) target plates were developed to compare and establish the standard curves for semi-quantitative analysis. The target plate can be placed on the target carrier of MS simultaneously with the conductive slide, which can simultaneously carry out vapor deposition or spray on the substrate, to ensure the parallelism of the pretreatment experiments between the standards and the actual vascular samples. The proposed method provided a powerful tool for evaluating the distributions and degradation process of biological stent materials in the coronary artery, as well as provided technical support for the research and development of degradable biological stents and product optimization.

Development of an LC-MS/MS Method for ARV-110, a PROTAC Molecule, and Applications to Pharmacokinetic Studies

ARV-110, a novel proteolysis-targeting chimera (PROTAC), has been reported to show satisfactory safety and tolerability for prostate cancer therapy in phase I clinical trials. However, there is a lack of bioanalytical assays for ARV-110 determination in biological samples. In this study, we developed and validated an LC-MS/MS method for the quantitation of ARV-110 in rat and mouse plasma and applied it to pharmacokinetic studies. ARV-110 and pomalidomide (internal standard) were extracted from the plasma samples using the protein precipitation method. Sample separation was performed using a C18 column and a mobile phase of 0.1% formic acid in distilled water–0.1% formic acid in acetonitrile (30:70, v/v). Multiple reaction monitoring was used to quantify ARV-110 and pomalidomide with ion transitions at m/z 813.4 → 452.2 and 273.8 → 201.0, respectively. The developed method showed good linearity in the concentration range of 2–3000 ng/mL with acceptable accuracy, precision, matrix effect, process efficiency, and recovery. ARV-110 was stable in rat and mouse plasma under long-term storage, three freeze-thaw cycles, and in an autosampler, but unstable at room temperature and 37 °C. Furthermore, the elimination of ARV-110 via phase 1 metabolism in rat, mouse, and human hepatic microsomes was shown to be unlikely. Application of the developed method to pharmacokinetic studies revealed that the oral bioavailability of ARV-110 in rats and mice was moderate (23.83% and 37.89%, respectively). These pharmacokinetic findings are beneficial for future preclinical and clinical studies of ARV-110 and/or other PROTACs.

Effects of 1α,25-dihydroxyvitamin D3 on the pharmacokinetics and biodistribution of ergothioneine, an endogenous organic cation/carnitine transporter 1 substrate, in rats

Purpose

This study aimed to investigate the effects of 1α,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) on the expression levels of organic cation/carnitine transporter 1 (OCTN1) as well as the pharmacokinetics and biodistribution of ergothioneine, an OCTN1 substrate, in rats.

Methods

Rats pretreated with 1,25(OH)₂D₃ (2.56 nmol/kg/day) for four days were administered ergothioneine (2 mg/kg) intravenously. The expression levels of rat OCTN1 (rOCTN1) in organs were determined using real-time quantitative polymerase chain reaction. Ergothioneine levels in plasma, urine, and organs (with and without intravenous injection of exogenous ergothioneine) were determined using liquid chromatography-tandem mass spectrometry.

Results

1,25(OH)₂D₃ pretreatment resulted in a significant decrease in rOCTN1 mRNA expression levels in the kidney and brain, a significant increase in basal plasma levels of ergothioneine (from 48 h), and a significant decrease in the tissue-plasma partition coefficient (K_p) in all tissues (except the heart and lungs) and the basal urine levels of ergothioneine. After intravenous administration, the pharmacokinetic profiles of ergothioneine were consistent with the basal levels of endogenous ergothioneine, with an increase in AUC_∞ by 85%, a significant decrease in total clearance by 49%, and a decrease in V_ss by 32% in 1,25(OH)₂D₃-treated rats. The K_p value and urinary recovery of ergothioneine also decreased in the 1,25(OH)₂D₃-treated group.

Conclusion

This study showed the effects of 1,25(OH)₂D₃ on the expression and function of rOCTN1 by investigating the interaction between 1,25(OH)₂D₃ and ergothioneine. Dose adjustment and possible changes in bioavailability should be considered before the co-administration of vitamin D or its active forms and OCTN1 substrates.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40005-022-00563-1.

TNBC: Potential Targeting of Multiple Receptors for a Therapeutic Breakthrough, Nanomedicine, and Immunotherapy

Triple-negative breast cancer (TNBC) is a heterogeneous, recurring cancer associated with a high rate of metastasis, poor prognosis, and lack of therapeutic targets. Although target-based therapeutic options are approved for other cancers, only limited therapeutic options are available for TNBC. Cell signaling and receptor-specific targets are reportedly effective in patients with TNBC under specific clinical conditions. However, most of these cancers are unresponsive, and there is a requirement for more effective treatment modalities. Further, there is a lack of effective biomarkers that can distinguish TNBC from other BC subtypes. ER, PR, and HER2 help identify TNBC and are widely used to identify patients who are most likely to respond to diverse therapeutic strategies. In this review, we discuss the possible treatment options for TNBC based on its inherent subtype receptors and pathways, such as p53 signaling, AKT signaling, cell cycle regulation, DNA damage, and programmed cell death, which play essential roles at multiple stages of TNBC development. We focus on poly-ADP ribose polymerase 1, androgen receptor, vascular endothelial growth factor receptor, and epidermal growth factor receptor as well as the application of nanomedicine and immunotherapy in TNBC and discuss their potential applications in drug development for TNBC.