Evodiamine and rutaecarpine from Tetradium ruticarpum in the treatment of liver diseases.

BACKGROUND: Liver is the pivotal organ responsible for plasma protein production, biliary secretion, xenobiotic elimination, glucose and lipid homeostasis. Dysregulation of these functions usually leads to liver diseases and further related complications. The incidence of liver diseases is increasing worldwide, with high morbidity and mortality when at advanced stages, and has become significant public health concern and substential economic burden. Thus, novel therapeutic strategies for managing liver diseases progression are urgently required. T. ruticarpum is one of the most famous and frequently used herbal medicine and has been prescribed in traditional Chinese medicine (TCM) formulas for the treatment of various ailments, including liver diseases. A considerable amount of bioactive ingredients have been isolated and identified from the roots of T. ruticarpum, including alkaloids, saponins, phenols, volatile oils and other compounds. Among these compounds, evodiamine (EVO) and rutaecarpine (RUT) are believed to be the most bioactive compounds. PURPOSE: To summarize recent findings regarding to the metabolism, pharmacological/toxicological effects of EVO and RUT and to highlight the potential therapeutic effects of them against liver diseases. METHODS: Online academic databases (including PubMed, Google Scholar, Web of Science and CNKI) were searched using search terms of "T. ruticarpum", "Wu Zhu Yu", "evodiamine", "rutaecarpine", "liver" and combinations to include published studies of EVO and RUT primarily from 2004-2019. Several critical previous studies beyond this period were also included. RESULTS: Evodiamine (EVO) and rutaecarpine (RUT) are believed to be the most bioactive alkaloids in T. ruticarpum, having anti-inflammation, anti-fibrosis, anti-lipotoxicity, anti-cancer activities, and thus having potential to improve liver disorders. In the current review, we comprehensively summarized recent progresses in the studies of EVO- and RUT-mediated promising hepatoprotective effects and also provide novel insights regarding the potential use of EVO and RUT as therapeutic options for the treatment of liver diseases. CONCLUSION: With further in-depth pharmacology and pharmacokinetic studies, we believe that natural products in T. ruticarpum and their derivatives will become promising medicines with improved clinical efficacy for the treatment of liver diseases in the immediate future.

A phase III randomized, multicentre, double blind, active controlled trial to compare the efficacy and safety of two different anagrelide formulations in patients with essential thrombocythaemia - the TEAM-ET 2·0 trial.

Anagrelide is an established treatment option for essential thrombocythaemia (ET). A prolonged release formulation was developed with the aim of reducing dosing frequency and improving tolerability, without diminishing efficacy. This multicentre, randomized, double blind, active-controlled, non-inferiority trial investigated the efficacy, safety and tolerability of anagrelide prolonged release (A-PR) over a reference product in high-risk ET patients, either anagrelide-naïve or -experienced. In a 6 to 12-week titration period the individual dose for the consecutive 4-week maintenance period was identified. The primary endpoint was the mean platelet count during the maintenance period (3 consecutive measurements, day 0, 14, 28). Of 112 included patients 106 were randomized. The mean screening platelet counts were 822 × 109 /l (95% confidence interval (CI) 707-936 × 109 /l) and 797 × 109 /l (95% CI 708-883 × 109 /l) for A-PR and the reference product, respectively. Both treatments effectively reduced platelet counts, to mean 281 × 109 /l for A-PR (95% CI 254-311) and 305 × 109 /l (95% CI 276-337) for the reference product (P < 0·0001, for non-inferiority). Safety and tolerability were comparable between both drugs. The novel prolonged-release formulation was equally effective and well tolerated compared to the reference product. A-PR provides a more convenient dosing schedule and will offer an alternative to licensed immediate-release anagrelide formulations.

In vivo and in vitro metabolism and pharmacokinetics of cholinesterase inhibitor deoxyvasicine from aerial parts of Peganum harmala Linn in rats via UPLC-ESI-QTOF-MS and UPLC-ESI-MS/MS.

ETHNOPHARMACOLOGICAL RELEVANCE: Aerial parts of Peganum harmala Linn are a Uighur traditional medicinal herb in China used to treat amnesia, bronchial asthma, and cough. Deoxyvasicine (DVAS), a potent cholinesterase inhibitor exhibiting anti-senile dementia activity, is one of the chief active ingredients in aerial parts of P. harmala and plays a key role in mediating the pharmacological effects of P. harmala. However, the metabolic profiling and in vivo pharmacokinetic characteristics of DVAS still remain unknown. AIM OF THE STUDY: The aim of this present study was to investigate the metabolism and pharmacokinetic properties of DVAS in rats by using ultra-performance liquid chromatography combined with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-QTOF-MS) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-ESI-MS/MS) method. MATERIALS AND METHODS: The metabolic profiling of DVAS was evaluated in vitro and in vivo by rat liver microsomes (RLMs) incubation and by rat bio-specimens, such as urine, feces, plasma, and bile, after the oral administration of 45 mg/kg DVAS. An efficient and sensitive UPLC-ESI-MS/MS method was developed and validated to simultaneously determine DVAS and its major four metabolites, namely, vasicine, deoxyvasicinone, vasicinone, and 1,2,3,9-tetrahydropyrrolo[2,1-b]quinazolin-3-ß-D-glucuronide in rat plasma. For pharmacokinetic studies, 32 Sprague-Dawley rats were randomly divided into four groups, namely, intravenous dosage group (2 mg/kg DVAS) and three oral dosage groups (5, 15, and 45 mg/kg DVAS). In addition, the activity of the components in plasma after intravenous administration of DVAS was evaluated by in vitro anti-butyrylcholinesterase (BChE) assays. RESULTS: A total of 23 metabolites were found in RLMs, plasma, urine, feces, and bile by UPLC-ESI-QTOF-MS. The metabolic pathway of DVAS in vivo and in vitro mainly involved hydroxylation, dehydrogenation, acetylation, methylation, glucuronidation, and O-sulphate conjugation, and the C-3 and C-9 sites were the main metabolic soft spots. All 23 metabolites were detected in the urine sample, and 13, 8, 22, and 6 metabolites were identified from rat feces, plasma, bile, and RLMs, respectively. The standard curves of DVAS and four metabolites in rat plasma showed good linearity in the concentration range of 0.82-524.00 ng/mL with acceptable selectivity, precision, accuracy, recovery, and stability. DVAS exhibited linear dose-proportional pharmacokinetics at doses of 5, 15, and 45 mg/kg after oral administration, and the average oral absolute bioavailability of DVAS was 47.46%. The in vitro anti-BChE assays implied that the inhibitive activities were mainly due to the different concentrations of prototype DVAS. CONCLUSIONS: DVAS can be rapidly absorbed and excreted by blood, and it is also extensively metabolized in vivo, and the anti-BChE activity in blood is mainly attributed to DVAS. These findings can lay a foundation for new drug development for DVAS.

Alterations of Gefitinib Pharmacokinetics by Co-administration of Herbal Medications in Rats.

OBJECTIVE: To evaluate the potential pharmacokinetic interactions of the anticancer agent gefitinib (Iressa®) and the oriental medications Guipi Decoction (, GPD, Guibi-tang in Korean) and Bawu Decoction (, BWD, Palmul-tang in Korean). METHODS: Methylcellulose (MC, control), GPD (1,200 mg/kg), or BWD (6,000 mg/kg) was orally administered to rats either as a single dose or multiple doses prior to gefitinib administration. To examine the effects of a single dose of the herbal medicines, gefitinib (10 mg/kg) was orally administered after 5 min or 1 h of MC or the herbal medicine pretreatments. To examine the effects of the multiple doses of the herbal medicines, gefitinib (10 mg/kg) was orally administered following 7 consecutive days of the administration of MC or each herbal medicine. The plasma concentrations of gefitinib were determined with liquid chromatography-tandem mass spectrometry assay. The plasma concentration-time profiles of gefitinib were analyzed with a noncompartmental analysis. RESULTS: Gefitinib was rapidly absorbed and showed a monoexponential decline with an elimination half-life of 3.7-4.1 h. The pharmacokinetics of gefitinib was not affected by GPD pretreatment. However, a significantly lower maximum plasma concentration (Cmax, P<0.05) and area under the curve (P<0.05), and a delayed time to reach Cmax (Tmax, P<0.01) were observed in both single- and multipledose BWD-pretreated rats compared with the control rats. CONCLUSIONS: BWD and not GPD might delay and interfere with gefitinib absorption. Further evaluations of the clinical significance of these findings are needed.

Pharmacokinetics of intravenous pan-class I phosphatidylinositol 3-kinase (PI3K) inhibitor [14C]copanlisib (BAY 80-6946) in a mass balance study in healthy male volunteers.

PURPOSE: To determine the pharmacokinetics of radiolabeled copanlisib (BAY 80-6946) in healthy male volunteers and to investigate the disposition and biotransformation of copanlisib. METHODS: A single dose of 12 mg copanlisib containing 2.76 MBq [14C]copanlisib was administered as a 1-h intravenous infusion to 6 volunteers with subsequent sampling up to 34 days. Blood, plasma, urine and feces were collected to monitor total radioactivity, parent compound and metabolites. RESULTS: Copanlisib treatment was well tolerated. Copanlisib was rapidly distributed throughout the body with a volume distribution of 1870 L and an elimination half-life of 52.1-h (range 40.4-67.5-h). Copanlisib was the predominant component in human plasma (84% of total radioactivity AUC) and the morpholinone metabolite M1 was the only circulating metabolite (about 5%). Excretion of drug-derived radioactivity based on all 6 subjects was 86% of the dose within a collection interval of 20-34 days with 64% excreted into feces as major route of elimination and 22% into urine. Unchanged copanlisib was the main component excreted into urine (15% of dose) and feces (30% of dose). Excreted metabolites (41% of dose) of copanlisib resulted from oxidative biotransformation. CONCLUSIONS: Copanlisib was eliminated predominantly in the feces compared to urine as well as by hepatic biotransformation, suggesting that the clearance of copanlisib would more likely be affected by hepatic impairment than by renal dysfunction. The dual mode of elimination via unchanged excretion of copanlisib and oxidative metabolism decreases the risk of clinically relevant PK-related drug-drug interactions.

A study of peritoneal metastatic xenograft model of colorectal cancer in the treatment of hyperthermic intraperitoneal chemotherapy with Raltitrexed.

Peritoneal metastasis of colorectal cancer is one of the most incident and fateful diseases among relapse cases. It shows a certain resistance to systemic chemotherapy. The perfusion system in clinic is complex and hard to be used in fundamental researches. This study aims at evaluating the effect of an improved hyperthermic intraperitoneal chemotherapy with Raltitrexed used in tumor-bearing mice with peritoneal metastatic colorectal carcinoma. The results showed that no severe adverse effect was observed. All control animals developed extensive peritoneal and mesenteric metastatic nodes. Tumor sites in the treatment groups were reduced significantly. The administration dose of Raltitrexed influenced concentration in systemic blood and peritoneal tissues. Temperature promoted the intracellular absorption of Raltitrexed significantly. Our findings reveal that hyperthermic intraperitoneal chemotherapy is an efficient therapy in treating peritoneal metastatic carcinoma in nude mice. It can effectively reduce the extension of carcinoma cells from macro and micro examination. The combination of hyperthermia and Raltitrexed resulted in an improved therapeutic effect on animal models.

UPLC-ESI-MS/MS study of the effect of green tea extract on the oral bioavailability of erlotinib and lapatinib in rats: Potential risk of pharmacokinetic interaction.

Green tea (GT) is one of the most consumed beverages worldwide. Tyrosine kinase inhibitors (TKIs) belong to the oral targeted therapy that gained much interest in oncology practice, among which are erlotinib (ERL) and lapatinib (LAP). Since green tea polyphenols (GTP) are known to be inhibitors of receptor tyrosine kinases, GTE could likely potentiate the anticancer effect of TKIs, but with a possibility of pharmacokinetic (PK) interaction with co-administered TKIs. In this study, the effect of GTE on the PK of ERL/LAP in rats was studied. UPLC-ESI-MS/MS method has been developed and validated for the quantification of ERL and LAP in rat plasma, using gefitinib (GEF) as the internal standard. Plasma samples were treated extensively by protein precipitation (PPT) followed by solid phase extraction (SPE) using octadecyl C 18/14% cartridges. Chromatographic analysis was carried out on Acquity UPLC BEH™ C18 column with a mobile phase consisting of water: acetonitrile (20: 80, v/v), each with 0.15% formic acid. Quantification was performed in the positive electrospray ionization (ESI+) mode with multiple reaction monitoring (MRM) of the transitions m/z 394.29→278.19 (ERL), m/z 581.07→365.13 (LAP), and m/z 447.08→128.21 (GEF). The method was fully validated as per the FDA guidelines showing linearity over the range of 0.4-1000 (ERL) and 0.6-1000 (LAP) ng/mL with very low lower limit of quantification (LLOQ) of 0.4 and 0.6ng/mL for ERL and LAP, respectively. The applicability of the method was extended to perform a comparative study of the PK of ERL/LAP following short-term and long-term administration of GTE, compared with their single oral administration. The results revealed that a significant reduction in the oral bioavailability was recorded with both ERL and LAP following the ingestion of GTE particularly for short-term administration. A reduction in Cmax (AUC) by 67.60% (69.50%) and 70.20% (73.96%), was recorded with short-term administration of GTE, compared with only 16.03% (21.09%) and 13.53% (22.12%) reduction for ERL and LAP, respectively, with long-term administration. Thus patients taking TKIs should preferably avoid drinking GT or ingesting GTE capsules during the period of treatment with TKIs.

Detection and characterization of the metabolites of rutaecarpine in rats based on ultra-high-performance liquid chromatography with linear ion trap-Orbitrap mass spectrometer.

CONTEXT: Rutaecarpine is an active indoloquinazoline alkaloid ingredient originating from Evodia rutaecarpa (Wu-zhu-yu in Chinese), which possesses a variety of effects. However, its metabolism has not been investigated thoroughly yet. OBJECTIVE: This study develops a highly sensitive and effective method for detection and characterization of the metabolites of rutaecarpine in Sprague-Dawley (SD) rats. MATERIALS AND METHODS: In this study, an efficient method was developed using ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometer (UHPLC-LTQ-Orbitrap MS) to detect the metabolism profile of rutaecarpine in rat plasma. First, a blood sample (1 mL) was withdrawn 2 h after oral administration of rutaecarpine in SD rats (50 mg/kg). Second, the blood was centrifuged at 4000 rpm for 10 min and pretreated by solid-phase extraction method. Third, 2 µL of the plasma was injected into UHPLC-LTQ-Orbitrap MS for analysis. Finally, the metabolites of rutaecarpine were tentatively identified based on accurate mass measurements, fragmentation patterns and chromatographic retention times. RESULTS: A total of 16 metabolites (four new metabolites, viz., dihydroxylation and sulphate conjugation products of rutaecarpine (M8-M11)) as well as parent drug itself, including three phase I and 12 phase II metabolites were detected and identified in rat plasma. Hydroxylation, sulphate conjugation and glucuronidation were confirmed as the primary metabolic pathways for rutaecarpine in rat plasma. DISCUSSION AND CONCLUSION: These results provide an insight into the metabolism of rutaecarpine and also can give strong indications on the effective forms of rutaecarpine in vivo.

Colossolactone H, a new Ganoderma triterpenoid exhibits cytotoxicity and potentiates drug efficacy of gefitinib in lung cancer.

Three pentacyclic triterpene dilactones were isolated from the fruiting bodies of Ganoderma colossum, a medicinal mushroom. Colossolactone H (colo H) as a new compound and the most cytotoxic among the isolates was studied for its anticancer mechanism and the potential use in cancer therapy. Gene expression profiling analysis indicated that treatment of lung cancer cells with colo H caused upregulation of 252 genes and downregulation of 398 genes. Gene ontology enrichment analysis indicated that the downregulated genes were the most significantly enriched in cell cycle progression, and the upregulated genes were significantly enriched in metabolic process, cellular response to stimulus, and oxidation reduction. Accordingly, colo H was found to halt cell growth and induce cell apoptosis via the elevation of cellular reactive oxygen species to cause DNA damage and the increase of tumor suppressor p53 protein. These events facilitate additive cytotoxicity of colo H and gefitinib for gefitinib-resistant H1650 lung cancer cells. Furthermore, combination of colo H and gefitinib effectively inhibited the growth of tumor xenografts in athymic mice. In addition to the efficacy in adjunctive cancer therapy, we have also demonstrated the isolation of colo H from cultivated G. colossum. Thus it is feasible to use colo H or Ganoderma colossum for cancer therapy.

Caco-2 Permeability Studies and In Vitro hERG Liability Assessment of Tryptanthrin and Indolinone.

Tryptanthrin and (E,Z)-3-(4-hydroxy-3,5-dimethoxybenzylidene)indolinone (indolinone) were recently isolated from Isatis tinctoria as potent anti-inflammatory and antiallergic alkaloids, and shown to inhibit COX-2, 5-LOX catalyzed leukotriene synthesis, and mast cell degranulation at low µM to nM concentrations. To assess their suitability for oral administration, we screened the compounds in an in vitro intestinal permeability assay using human colonic adenocarcinoma cells. For exact quantification of the compounds, validated UPLC-MS/MS methods were used. Tryptanthrin displayed high permeability (apparent permeability coefficient > 32.0 × 10(-6) cm/s) across the cell monolayer. The efflux ratio below 2 (< 1.12) and unchanged apparent permeability coefficient values in the presence of the P-glycoprotein inhibitor verapamil (50 µM) indicated that tryptanthrin was not involved in P-glycoprotein interactions. For indolinone, a low recovery was found in the human colon adenocarcinoma cell assay. High-resolution mass spectrometry pointed to extensive phase II metabolism of indolinone (sulfation and glucuronidation). Possible cardiotoxic liability of the compounds was assessed in vitro by measurement of an inhibitory effect on human ether-a-go-go-related gene tail currents in stably transfected HEK 293 cells using the patch clamp technique. Low human ether-a-go-go-related gene inhibition was found for tryptanthrin (IC50 > 10 µM) and indolinone (IC50 of 24.96 µM). The analysis of compounds using various in silico methods confirmed favorable pharmacokinetic properties, as well as a slight inhibition of the human ether-a-go-go-related gene potassium channel at micromolar concentrations.

Pharmacokinetics and In Vitro Blood-Brain Barrier Screening of the Plant-Derived Alkaloid Tryptanthrin.

The indolo[2,1-b]quinazoline alkaloid tryptanthrin was previously identified as a potent anti-inflammatory compound with a unique pharmacological profile. It is a potent inhibitor of cyclooxygenase-2, 5-lipooxygenase-catalyzed leukotriene synthesis, and nitric oxide production catalyzed by the inducible nitric oxide synthase. To characterize the pharmacokinetic properties of tryptanthrin, we performed a pilot in vivo study in male Sprague-Dawley rats (2 mg/kg bw i. v.). Moreover, the ability of tryptanthrin to cross the blood-brain barrier was evaluated in three in vitro human and animal blood-brain barrier models. Bioanalytical UPLC-MS/MS methods used were validated according to current international guidelines. A half-life of 40.63 ± 6.66 min and a clearance of 1.00 ± 0.36 L/h/kg were found in the in vivo pharmacokinetic study. In vitro data obtained with the two primary animal blood-brain barrier models showed a good correlation with an immortalized human monoculture blood-brain barrier model (hBMEC cell line), and were indicative of a high blood-brain barrier permeation potential of tryptanthrin. These findings were corroborated by the in silico prediction of blood-brain barrier penetration. P-glycoprotein interaction of tryptanthrin was assessed by calculation of the efflux ratio in bidirectional permeability assays. An efflux ratio below 2 indicated that tryptanthrin is not subjected to active efflux.

Mechanism-based inhibition of CYPs and RMs-induced hepatoxicity by rutaecarpine.

1. Rutaecarpine, a quinolone alkaloid isolated from the unripe fruit of Evodia rutaecarpa, is one of the main active components used in a variety of clinical applications, including the treatment of hypertension and arrhythmia. However, its hepatotoxicity has also been reported in recent years. 2. Reactive metabolites (RMs) play a vital role in drug-induced liver injury. Rutaecarpine has a secondary amine structure that may be activated to RMs. The aim of the study was to investigate the inhibition of rutaecarpine on CYPs and explore the possible relationship between RMs and potential hepatotoxicity. 3. A cell counting kit-8 cytotoxicity assay indicated that rutaecarpine can decrease the primary rat hepatocyte viability, increase lactate dehydrogenase and reactive oxygen species, reduce JC-1, and cause cell stress and membrane damage. The indexes were significantly restored by adding ABT, an inhibitor of CYPs. A cocktail assay showed that CYP1A2, CYP2C9, CYP2C19, CYP2E1 and CYP3A4 can be inhibited by rutaecarpine in human liver microsomes. The IC50 values of CYP1A2 with and without NADPH were 2.2 and 7.4 µM, respectively, which presented a 3.3 shift. The results from a metabolic assay indicated that three mono-hydroxylated metabolites and two di-hydroxylated metabolites were identified and two GSH conjugates were also trapped. 4. Rutaecarpine can inhibit the activities of CYPs and exhibit a potential mechanism-based inhibition on CYP1A2. RMs may cause herb-drug interactions, providing important information for predicting drug-induced hepatotoxicity.

[Pharmacokinetics behavior of raltitrexed in rats after repeatedly injected with Huangqi injection].

In this study, the variation of pharmacokinetics behavior of raltitrexed (RTX) in rats after repeatedly injected with Huangqi injection was investigated. Twelve SD rats were divided into two groups: the multidose group and the RTX group. Rats in multidose group were iv. injected with Huangqi injection (dose of 1.575 mL x kg(-1)) everyday at 8 am for a week, and had free accesses for food and water. The rats were fasted for food but not water since 8 h before the eighth day. At the eighth morning, firstly, rats were injected with Huangqi injection (dose of 1.575 mL x kg(-1)), and 5 min later, were injected with RTX (dose of 0.467 mg x kg(-1)); rats in RTX group were not disposed in the previous seven days, also had free accesses for food and water, and were iv. injected with raltitrexed at the same time as Multidose group at the eighth day morning. Rat plasma was collected at different time and processed with methanol to precipitate the protein before HPLC assays. The pharmacokinetics parameters for two groups were calculated by software 3P97. Through the observation of drug concentration in plasma and time curve, we found that at almost every time point the concentration of RTX in plasma in multidose group was lower than the RTX group. When comparing the pharmacokinetics parameters between the multidose group and the RTX group, the average of AUC(0-t) and half-life(t1/2) of multidose group were decreased from 56 080 microg x min x L(-1) and 15.07 min to 35 834 microg x min x L(-1) and 8.95 min, respectively, while the clearance (CL) was increased from 0.51 to 0.83 mL x h(-1). Therefore, it could be deduced that repeatedly injected with AR injection may influence the renal excretion and glycometabolism of RTX, thus change pharmacokinetics behavior of raltitrexed in rats plasma. This result may give us a hint to prudantly manage the drug combination of RTX and Huangqi injection.

Distribution study of tryptanthrin in rat tissues by HPLC and its relationship with meridian tropism of indigo naturalis in traditional Chinese medicine.

The aim of the present study is to characterize the distribution of tryptanthrin (TRYP) in rat tissues following oral administration at a dose of 100 mg/kg and its relationship with meridian tropism (MT) of indigo naturalis (IN) in traditional Chinese medicine (TCM). For quantitative analysis in biological samples, a sensitive, inexpensive and accurate high-performance liquid chromatographic method was developed and validated with 2-hydroxy acetophenone as internal standard, a Shimadzu C18 column and water-acetonitrile (55:45, v/v) as mobile phase. Acceptable intra-day and inter-day precision at high, medium and low concentration was acquired with RSD ranging from 0.87 to 5.22% and from 1.25 to 6.47%, respectively. Good assay and extraction recoveries were obtained with a single and relatively fast step to precipitate protein. The extraction recovery of TRYP ranged from 87.5 to 94.5 %. TRYP concentration was highest in the liver and remained for a much longer time than in other tissues. It could also be detected in kidney, lung, heart and spleen, but not in brain under the experimental conditions. The results confirmed the traditional knowledge of TCM that MT of IN belongs to the liver meridians and demonstrated that TRYP is one of the active constituents of the MT of IN.

Preclinical pharmacokinetics and disposition of a novel selective VEGFR inhibitor fruquintinib (HMPL-013) and the prediction of its human pharmacokinetics.

PURPOSE: This study evaluated the preclinical pharmacokinetics (PK) and disposition of fruquintinib (HMPL-013), a small molecule vascular endothelial growth factor receptors inhibitor. METHODS: In vitro and in vivo PK/ADME assays were conducted. Allometry and PK modeling/simulation were conducted to predict human PK parameters and the time course profiles. RESULTS: HMPL-013 has high permeability without efflux. It shows moderate oral bioavailability of 42-53 % and Tmax < 4 h in mouse, rat, dog and monkey, with exposure-dose linearity proved in rats and dogs. No significant food effect is on dog PK. HMPL-013 has moderately high tissue distribution. It majorly distributes in gastrointestinal tract, liver, kidney, adrenal and adipose. The plasma protein binding fraction is 88-95 % in mouse, rat, dog and human, invariable up to 10 µM. The in vivo clearance of HMPL-013 is low, consistent with the in vitro scaling. Three major oxidative metabolites were identified in liver microsomes of mouse, rat, dog, monkey and human. Dog is mostly similar to human regarding in vitro metabolism. Demethylation, hydroxylation and sequential glucuronidation are the major in vivo metabolic reactions. Direct urinary and biliary excretion of HMPL-013 is negligible. Metabolizing to M1 (demethylation), sequentially glucuronidating, followed by biliary excretion, and to a less extent, by urinary excretion, are important elimination pathways for HMPL-013 in rats. HMPL-013 has low risk of drug-drug interaction. It is predicted to have favorable human PK properties and low efficacious dose. CONCLUSION: HMPL-013 demonstrates good preclinical PK and enables successful human PK and dose projection. It is valuable for further clinical development.

Vandetanib for the treatment of thyroid cancer: an update.

INTRODUCTION: Medullary thyroid carcinoma (MTC) is a rare endocrine malignancy accounting for a significant percentage of thyroid cancer-related fatal events. Traditional treatment modalities used in the other types of thyroid carcinomas have been proved largely ineffective in advanced MTC. Better understanding of the molecular pathways implicated in the pathogenesis of MTC has led to the development of new drugs, which are implicated in the disruption of these molecular cascades. AREAS COVERED: This review provides the latest information regarding vandetanib , a new tyrosine kinase inhibitor mainly in the treatment of MTC. A collection of available data was conducted using the PubMed database as well as the ClinicalTrials.gov website, searching for vandetanib and thyroid cancer. EXPERT OPINION: Vandetanib targets multiple cell-signaling pathways involved in the molecular pathogenesis of thyroid cancer, namely vascular endothelial growth factor receptor-2, epidermal growth factor receptor and rearranged during transfection receptor. It is an effective approach in treating advanced MTC. However, treatment toxicity issues, as well as individual patient parameters, including disease burden and progression, should be taken into consideration before initiating vandetanib treatment.

Marsdenia tenacissima extract inhibits gefitinib metabolism in vitro by interfering with human hepatic CYP3A4 and CYP2D6 enzymes.

ETHNOPHARMACOLOGICAL RELEVANCE: The stem of Marsdenia tenacissima (Roxb.) Wight et Arn. is mainly produced in Yunnan China and has long been used as a medicine to treat cancer in China. Xiao-Ai-Ping injection, the water-soluble part of the stem of Marsdenia tenacissima, is administrated as an anti-cancer agent in clinics for decades. Our previous study showed that Marsdenia tenacissima extract (MTE) restored gefitinib sensitivity in gefitinib-resistant non-small cell lung cancer (NSCLC) cells, but the mechanism involved is unknown. Gefitinib undergoes hepatic metabolism predominantly through human cytochrome P450 (CYP) 3A4 and CYP2D6 enzymes. This study aims to evaluate whether MTE interferes with gefitinib metabolism via human hepatic P450 enzymes. MATERIAL AND METHODS: A cocktail-substrate assay was used to test the effect of MTE on major CYP enzyme activities by incubation of pooled human liver microsomes with specific substrate probes of CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 in the absence and presence of MTE. Recombinant human CYP450 enzymes were used to predict in vitro gefitinib metabolic clearance in the absence and presence of MTE. The metabolites of the substrate probes and gefitinib were detected by high-performance liquid chromatographic tandem mass spectrometry (HPLC-MS/MS). Human hepatoma HepG2 cells were used to investigate the effect of gefitinib alone or in combination with MTE on CYP3A4 and CYP2D6 mRNA and protein expression. RESULTS: The cocktail-substrate assay showed that MTE inhibited CYP450 activities in human liver microsomes with the inhibition rate of 3A4>2C9>2C19>1A2>2D6. The co-administration of MTE with gefitinib significantly decreased the in vitro intrinsic clearance (Clint) of gefitinib by 2.6 and 4.0-fold for CYP2D6 and CYP3A4, respectively, but did not affect other CYP450s. CYP2D6 and CYP3A4 mRNA and protein expression in human hepatoma HepG2 cells were greatly reduced in the combined gefitinib and MTE treatment. CONCLUSION: We demonstrate that MTE inhibits gefitinib metabolism by interfering with CYP3A4 and CYP2D6. Meanwhile, MTE combined with gefitinib down-regulates the mRNA and protein expression of CYP3A4 and CYP2D6 in the HepG2 cells. Thus, these data suggest that MTE is a promising herbal medicine to enhance gefitinib efficacy through improving its metabolic stability.

BAY 80-6946 is a highly selective intravenous PI3K inhibitor with potent p110α and p110δ activities in tumor cell lines and xenograft models.

Because of the complexity derived from the existence of various phosphoinositide 3-kinase (PI3K) isoforms and their differential roles in cancers, development of PI3K inhibitors with differential pharmacologic and pharmacokinetic profiles would allow best exploration in different indications, combinations, and dosing regimens. Here, we report BAY 80-6946, a highly selective and potent pan-class I PI3K inhibitor with sub-nanomolar IC50s against PI3Kα and PI3Kδ. BAY 80-6946 exhibited preferential inhibition (about 10-fold) of AKT phosphorylation by PI3Kα compared with PI3Kß in cells. BAY 80-6946 showed superior antitumor activity (>40-fold) in PIK3CA mutant and/or HER2 overexpression as compared with HER2-negative and wild-type PIK3CA breast cancer cell lines. In addition, BAY 80-6946 revealed potent activity to induce apoptosis in a subset of tumor cells with aberrant activation of PI3K as a single agent. In vivo, single intravenous administration of BAY 80-6946 exhibited higher exposure and prolonged inhibition of pAKT levels in tumors versus plasma. BAY 80-6946 is efficacious in tumors with activated PI3K when dosed either continuously or intermittently. Thus, BAY 80-6946 induced 100% complete tumor regression when dosed as a single agent every second day in rats bearing HER2-amplified and PIK3CA-mutated KPL4 breast tumors. In combination with paclitaxel, weekly dosing of BAY 80-6946 is sufficient to reach sustained response in all animals bearing patient-derived non-small cell lung cancer xenografts, despite a short plasma elimination half-life (1 hour) in mice. Thus, BAY 80-6946 is a promising agent with differential pharmacologic and pharmacokinetic properties for the treatment of PI3K-dependent human tumors.

[Pharmacokinetics behavior of raltitrexed in rats after single injected with astragali radix].

To study pharmacokinetics behavior of Raltitrexed (RTX) after single injected with Radix Astragali (RA); twelve rats were divided into two groups: RTX (administrated iv. of raltitrexed); RTX with RA (administrated iv. of raltitrexed after single iv. dose of 3. 15 g x kg(-1)), rat plasma was collected and processed before HPLC assays; The established HPLC method was rapid, specific and precise. Between RTX and RTX with RA groups, half-life (t1/2), AUC(0-t) and CL showed no statistically significant differences; RA co-administration did not affect the pharmacokinetics of raltitrexed.

The role of afatinib in the management of non-small cell lung carcinoma.

INTRODUCTION: Despite initial patient benefit, drug resistance to first-generation EGFR tyrosine kinase inhibitors (TKIs) is inevitable. One of the key mechanisms responsible for the development of acquired drug resistance is the secondary T790M missense mutation in exon 20 of the EGFR kinase domain. Afatinib is an ATP-competitive small molecule inhibitor that potently and irreversibly inhibits EGFR and mutated EGFR including the T790M variant, as well as other members of the ErbB family in preclinical studies. AREAS COVERED: The authors describe the rationale and provide the preclinical background to afatinib and its potential as a NSCLC therapy. Specifically, the authors detail the drug's pharmaco-kinetic profile and review its clinical efficacy and toxicity profile. EXPERT OPINION: Afatinib is an effective treatment option for therapy-naive advanced NSCLC harboring an activating EGFR mutation. Furthermore, it is also of potential benefit to patients with acquired resistance to EGFR kinase inhibitors. In the future, the authors envision the clinical development of third-generation EGFR mutation-specific inhibitors in NSCLC, which may potentially spare normal tissue toxicity. Nevertheless, afatinib currently represents a bona fide treatment option in the NSCLC therapeutic armamentarium.