Antiplatelet and myocardial protective effect of Shexiang Tongxin Dropping Pill in patients undergoing percutaneous coronary intervention: A randomized controlled trial.

BACKGROUND: High on-clopidogrel platelet reactivity could be partially explained by loss-of-function alleles of CYP2C19, the enzyme that converts clopidogrel into its active form. Shexiang Tongxin Dropping Pill (STDP) is a traditional Chinese medicine to treat angina pectoris. STDP has been shown to improve blood flow in patients with slow coronary flow and attenuate atherosclerosis in apolipoprotein E-deficient mice. However, whether STDP can affect platelet function remains unknown. OBJECTIVE: The purpose of this study is to examine the potential effects of STDP on platelet function in patients undergoing percutaneous coronary intervention (PCI) for unstable angina. The interaction between the effects of STDP with polymorphisms of CYP2C19 was also investigated. DESIGN, PARTICIPANTS AND INTERVENTION: This was a single-center, randomized controlled trial in patients undergoing elective PCI for unstable angina. Eligible subjects were randomized to receive STDP (210 mg per day) plus dual antiplatelet therapy (DAPT) with clopidogrel and aspirin or DAPT alone. MAIN OUTCOME MEASURES: The primary outcome was platelet function, reflected by adenosine diphosphate (ADP)-induced platelet aggregation and platelet microparticles (PMPs). The secondary outcomes were major adverse cardiovascular events (MACEs) including recurrent ischemia or myocardial infarction, repeat PCI and cardiac death; blood biomarkers for myocardial injury including creatine kinase-MB isoenzyme (CK-MB) and high-sensitive troponin I (hsTnI); and biomarkers for inflammation including intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), monocyte chemoattractant protein-1 (MCP-1) and galectin-3. RESULTS: A total of 118 subjects (mean age: [66.8 ± 8.9] years; male: 59.8%) were included into analysis: 58 in the control group and 60 in the STDP group. CYP2C19 genotype distribution was comparable between the 2 groups. In comparison to the control group, the STDP group had significantly lower CK-MB (P < 0.05) but similar hsTnI (P > 0.05) at 24 h after PCI, lower ICAM-1, VCAM-1, MCP-1 and galectin-3 at 3 months (all P < 0.05) but not at 7 days after PCI (P > 0.05). At 3 months, the STDP group had lower PMP number ([42.9 ± 37.3] vs. [67.8 ± 53.1] counts/µL in the control group, P = 0.05). Subgroup analysis showed that STDP increased percentage inhibition of ADP-induced platelet aggregation only in slow metabolizers (66.0% ± 20.8% in STDP group vs. 36.0% ± 28.1% in the control group, P < 0.05), but not in intermediate or fast metabolizers. The rate of MACEs during the 3-month follow-up did not differ between the two groups. CONCLUSION: STDP produced antiplatelet, anti-inflammatory and cardioprotective effects. Subgroup analysis indicated that STDP inhibited residual platelet reactivity in slow metabolizers only. TRIAL REGISTRATION: This study was registered on www.chictr.org.cn: ChiCTR-IPR-16009785.

Antiplatelet and myocardial protective effect of Shexiang Tongxin Dropping Pill in patients undergoing percutaneous coronary intervention: A randomized controlled trial / 中西医结合学报

BACKGROUND@#High on-clopidogrel platelet reactivity could be partially explained by loss-of-function alleles of CYP2C19, the enzyme that converts clopidogrel into its active form. Shexiang Tongxin Dropping Pill (STDP) is a traditional Chinese medicine to treat angina pectoris. STDP has been shown to improve blood flow in patients with slow coronary flow and attenuate atherosclerosis in apolipoprotein E-deficient mice. However, whether STDP can affect platelet function remains unknown.@*OBJECTIVE@#The purpose of this study is to examine the potential effects of STDP on platelet function in patients undergoing percutaneous coronary intervention (PCI) for unstable angina. The interaction between the effects of STDP with polymorphisms of CYP2C19 was also investigated.@*DESIGN, PARTICIPANTS AND INTERVENTION@#This was a single-center, randomized controlled trial in patients undergoing elective PCI for unstable angina. Eligible subjects were randomized to receive STDP (210 mg per day) plus dual antiplatelet therapy (DAPT) with clopidogrel and aspirin or DAPT alone.@*MAIN OUTCOME MEASURES@#The primary outcome was platelet function, reflected by adenosine diphosphate (ADP)-induced platelet aggregation and platelet microparticles (PMPs). The secondary outcomes were major adverse cardiovascular events (MACEs) including recurrent ischemia or myocardial infarction, repeat PCI and cardiac death; blood biomarkers for myocardial injury including creatine kinase-MB isoenzyme (CK-MB) and high-sensitive troponin I (hsTnI); and biomarkers for inflammation including intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), monocyte chemoattractant protein-1 (MCP-1) and galectin-3.@*RESULTS@#A total of 118 subjects (mean age: [66.8 ± 8.9] years; male: 59.8%) were included into analysis: 58 in the control group and 60 in the STDP group. CYP2C19 genotype distribution was comparable between the 2 groups. In comparison to the control group, the STDP group had significantly lower CK-MB (P < 0.05) but similar hsTnI (P > 0.05) at 24 h after PCI, lower ICAM-1, VCAM-1, MCP-1 and galectin-3 at 3 months (all P < 0.05) but not at 7 days after PCI (P > 0.05). At 3 months, the STDP group had lower PMP number ([42.9 ± 37.3] vs. [67.8 ± 53.1] counts/μL in the control group, P = 0.05). Subgroup analysis showed that STDP increased percentage inhibition of ADP-induced platelet aggregation only in slow metabolizers (66.0% ± 20.8% in STDP group vs. 36.0% ± 28.1% in the control group, P < 0.05), but not in intermediate or fast metabolizers. The rate of MACEs during the 3-month follow-up did not differ between the two groups.@*CONCLUSION@#STDP produced antiplatelet, anti-inflammatory and cardioprotective effects. Subgroup analysis indicated that STDP inhibited residual platelet reactivity in slow metabolizers only.@*TRIAL REGISTRATION@#This study was registered on www.chictr.org.cn: ChiCTR-IPR-16009785.

Implications of Cannabidiol in Pharmacogenomic-Based Drug Interactions with CYP2C19 Substrates.

This is a patient case exploring the importance of evaluating herbal and dietary supplements and how they may impact drug-drug and drug-gene implications based on pharmacogenomics test results. Even though herbal supplements are considered natural by many patients, which is often the reason for starting them, herbal supplements may still be metabolized by the same pathways as other medications, potentially contributing to drug-drug, drug-herb, and drug-gene interactions, and therefore, potentially impacting a patient's response to medications.

In vitro effects of 95% khat ethanol extract (KEE) on human recombinant cytochrome P450 (CYP)1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2 and CYP3A5.

OBJECTIVES: Khat, a natural amphetamine-like psychostimulant plant, are widely consumed globally. Concurrent intake of khat and xenobiotics may lead to herb-drug interactions and adverse drug reactions (ADRs). This study is a continuation of our previous study, targeted to evaluate the in vitro inhibitory effects of khat ethanol extract (KEE) on human cytochrome (CYP) 1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2, and CYP3A5, major human drug metabolizing enzymes. METHODS: In vitro fluorescence enzyme assays were employed to assess CYPs inhibition with the presence and absence of various KEE concentrations. RESULTS: KEE reversibly inhibited CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2 and CYP3A5 but not CYP1A2 with IC50 values of 25.5, 99, 4.5, 21, 27, 17, and 10 µg/mL respectively. No irreversible inhibition of KEE on all the eight CYPs were identified. The Ki values of CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2 and CYP3A5 were 20.9, 85, 4.8, 18.3, 59.3, 3, and 21.7 µg/mL, respectively. KEE inhibited CYP2B6 via competitive or mixed inhibition; CYP2E1 via un-competitive or mixed inhibition; while CYP2A6, CYP2C8, CYP2C19, CYP2J2 and CYP3A5 via non-competitive or mixed inhibition. CONCLUSIONS: Caution should be taken by khat users who are on medications metabolized by CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2, and CYP3A5.

CYP2C19 is involved in the effect of Wuzhi tablet (Schisandra sphenanthera extract) and its constituents on the pharmacokinetics of intravenous voriconazole.

The co-administration of voriconazole (VCZ) and Wuzhi tablet (WZ) is frequently prescribed for solid organ transplantation patients in China. However, the pharmacokinetic interactions between VCZ and WZ as well as its bioactive constituents, such as schisandrin A and schisandrol B, remain unknown. Therefore, the effects of WZ and the two lignans on the metabolism of VCZ and the potential role of cytochromeP450 (CYP450), especially cytochrome P450 2C19 (CYP2C19), were investigated. The results showed that WZ extensively inhibited the activities of CYP1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, and 3A4. Noteworthy, 2.5 mg/mL WZ almost completely inhibited the activity of 2C19, and the inhibition ratio reached 78.6±3% and 63.5±4.6% for schisandrin A and schisandrol B at concentrations 100 µM, respectively. In addition, rats were treated with a single or consecutive 14 day oral dose of WZ (250 mg/kg), schisandrol B (10 mg/kg) and schisandrin A (10 mg/ kg). In rats treated with WZ, the AUC0-∞ value for intravenous VCZ dosing was increased by 80.2% (single dose, p < 0.05) and 66.4% (dosage for 14 day, p < 0.05) and the Cmax was increased by 10.5% (p < 0.05) and (20.6%, p < 0.05), respectively, much greater than that when VCZ (28 mg/kg) was given alone. Unexpectedly, the AUC and Cmax values after schisandrol B and schisandrin A treatment were significantly increased. However, the mRNA expression of liver CYP2C19 and the protein expression of liver CYP2C19 were surprisingly increased after treatment with WZ, schisandrol B and schisandrin A in rats. Therefore, attention should be paid to when WZ and VCZ are administered concomitantly, as dosage adjustment might become necessary. Further clinical study is warranted to validate the interaction between WZ and VCZ.

Effect of High-Dose Esomeprazole on CYP1A2, CYP2C19, and CYP3A4 Activities in Humans: Evidence for Substantial and Long-lasting Inhibition of CYP2C19.

In vitro, esomeprazole is a time-dependent inhibitor of CYP2C19. Additionally, racemic omeprazole induces CYP1A2 and omeprazole and its metabolites inhibit CYP3A4 in vitro. In this 5-phase study, 10 healthy volunteers ingested 20 mg pantoprazole, 0.5 mg midazolam, and 50 mg caffeine as respective index substrates for CYP2C19, 3A4, and 1A2 before and 1, 25, 49 (pantoprazole only), and 73 hours after an 8-day pretreatment with 80 mg esomeprazole twice daily. The area under the plasma concentration-time curve (AUC) of R-pantoprazole increased 4.92-fold (90% confidence interval (CI) 3.55-6.82), 2.31-fold (90% CI 1.85-2.88), and 1.33-fold (90% CI 1.06-1.68) at the 1-hour, 25-hour, and 73-hour phases, respectively, consistent with a substantial and persistent inhibition of CYP2C19. The AUC of midazolam increased up to 1.44-fold (90% CI 1.22-1.72) and the paraxanthine/caffeine metabolic ratio up to 1.19-fold (90% CI 1.04-1.36), when the index substrates were taken 1 hour after esomeprazole. Based on the recovery of R-pantoprazole oral clearance, the turnover half-life of CYP2C19 was estimated to average 53 hours. Pharmacokinetic simulation based on the observed concentrations of esomeprazole and its metabolites as well as their published CYP2C19 inhibitory constants was well in line with the observed changes in R-pantoprazole pharmacokinetics during the course of the study. Extrapolations assuming linear pharmacokinetics of esomeprazole suggested weak to moderate inhibition at 20 and 40 mg twice daily dosing. In conclusion, high-dose esomeprazole can cause strong inhibition of CYP2C19, but only weakly inhibits CYP3A4 and leads to minor induction of CYP1A2. The enzymatic activity of CYP2C19 recovers gradually in ~ 3-4 days after discontinuation of esomeprazole treatment.

[Efficacy of H. pylori eradication depending on genetic polymorphism of CYP2C19, MDR1 and IL-1ß].

AIM: To evaluate an association of genetic polymorphisms CYP2C19, MDR1, and IL-1ß on the eradication rate by 10-day modified therapy in patients with H. pylori - associated diseases. MATERIALS AND METHODS: In this study was conducted a prospective, randomized trial, included 89 patients with H. pylori - associated diseases. They were divided into 2 groups depending on therapy: clarithromycin 500 mg, b.i.d., amoxicillin 1000 mg, b.i.d., bismuth subcitrate 240 mg, b.i.d. rabeprazole 20 mg or 40 mg, b.i.d. for 10 days. All subjects underwent pharmacogenetic testing of CYP2C19, MDR1, and IL-1ß. RESULTS AND DISCUSSION: Per - protocol (PP) eradication rates in group with rabeprazole 40 mg were 97.6% (41/42; 95% CI 87.7-99.6), in group with rabeprazole 20 mg were 82.1% (32/39; 95% CI 67.3-91.0). Intention - to - treat analysis in group with rabeprazole 40 mg eradication rates were 89.1% (41/46; 95% CI 77.0-95.3), in group with standard dose rabeprazole - 74.4% (32/43; 95% CI 59.8-85.1). No significant differences in eradication rates between the groups of ultrarapid, rapid, normal and intermediate CYP2C19 metabolizers (PP: 93.5%/90.3%/84.6% respectively; χ2=0.87, p=0.65). Eradication rates in group with IL-1ß CC genotype there was no difference among the IL-1ß CT and TT genotype groups (PP: 92.9%/85.7%/94.7% respectively; χ2=1.34; p=0.51). The cure rate among MDR1 TT genotype was significantly lower than among subjects in the MDR1 CC/CT genotype groups (PP: 76.2% vs 96.3%: χ2=5.04; p=0.025; OR=8.13). CONCLUSION: Ten - day modified triple therapy with high dose rabeprazole significantly high eradication rates in patients with H. pylori - associated diseases. Independent factor for treatment failure is MDR1 CC/CT genotype status.

Clinical application and importance of one-step human CYP2C19 genotype detection.

BACKGROUND: To directly achieve cytochrome P450 2C19 gene ( CYP2C19) classification using one-step real-time fluorescent PCR detection and to verify the capabilities of this method with nucleic acid extracted from whole blood samples. METHODS: A human CYP2C19 genotyping kit based on one-step real-time fluorescent PCR detection was used to analyze whole blood or genomic DNA samples. This method was compared with pyrosequencing and another quantitative (q)PCR kit for its accuracy, repeatability, detection range analysis, sensitivity, specificity, and anti-interference analysis. RESULTS: The one-step real-time PCR method achieved a 100% accuracy rate compared with pyrosequencing and the other qPCR kit. When detecting different concentrations of known genes, concentrations of each sample ranging from 0.2 to 125 ng/µL could be correctly detected. The genotypes of samples treated with anticoagulants, including EDTA and sodium citrate, and chyle blood samples could be correctly detected. CONCLUSION: The one-step detection method demonstrated high accuracy and a wide detection range. It also had high levels of repeatability, sensitivity, and specificity for the assessment of genomic DNA test samples.

Pharmacogenetic variants and vitamin K deficiency: a risk factor or trigger for fibrosing interstitial pneumonias?

PURPOSE OF REVIEW: Fibrosing interstitial pneumonias are associated with various stages of fibrosis. The cause of this group of syndromes remains largely unknown. For most of these diseases, a genetic basis, environmental factors and certain triggers have been suggested as possible risk factors. Various studies have found an association between genetic polymorphisms, or the presence of certain variant alleles, and the occurrence and/or progression of interstitial pneumonias of unknown origin. An acute exacerbation of idiopathic pulmonary fibrosis shows characteristics of diffuse alveolar haemorrhage (DAH). DAH can be aggravated by vitamin K deficiency. This review deals with pharmacogenetic factors underlying interindividual differences of vitamin K status in patients with interstitial pneumonias and the possibilities for a personalized approach to patient management. RECENT FINDINGS: DAH has been associated with the presence of variant alleles in vitamin K epoxide reductase complex 1, cytochrome P450 (CYP)2C9 and CYP2C19 genes. Vitamin K deficiency has been associated with an increased risk for the development of DAH and progression and/or deterioration of interstitial pneumonias. This is in line with plausible pathophysiological mechanisms. However, clinical use should be confirmed. SUMMARY: DAH has been associated with vitamin K deficiency and suggested as potential trigger of fibrosing interstitial pneumonias. Information on genetic variation might benefit ongoing/new clinical trials, design of which should reflect needs to address relevance of testing gene variants. Whether vitamin K supplementation may prevent exacerbations or progression of interstitial pneumonias needs to be explored in future studies.

Optimization of Voriconazole Therapy for the Treatment of Invasive Fungal Infections in Adults.

Therapeutic concentrations of voriconazole in invasive fungal infections (IFIs) are ensured using a drug monitoring approach, which relies on attainment of steady-state pharmacokinetics. For voriconazole, time to reach steady state can vary from 5-7 days, not optimal for critically ill patients. We developed a population pharmacokinetic/pharmacodynamic model-based approach to predict doses that can maximize the net benefit (probability of efficacy-probability of adverse events) and ensure therapeutic concentrations, early on during treatment. The label-recommended 200 mg voriconazole dose resulted in attainment of targeted concentrations in ≥80% patients in the case of Candida spp. infections, as compared to only 40-50% patients, with net benefit ranging from 5.8-61.8%, in the case of Aspergillus spp. infections. Voriconazole doses of 300-600 mg were found to maximize the net benefit up to 51-66.7%, depending on the clinical phenotype (due to CYP2C19 status and pantoprazole use) of the patient and type of Aspergillus infection.

Cerium dioxide-doped carboxyl fullerene as novel nanoprobe and catalyst in electrochemical biosensor for amperometric detection of the CYP2C19*2 allele in human serum.

The disposition dose of clopidogrel is different in CYP2C19*2 gene carriers and non-carriers. High-dose clopidogrel has been recommended to overcome a low-responsiveness to clopidogrel in patients with the CYP2C19*2 gene. To guide the choice of clopidogrel dosage and catalyse a development in the field of personalized therapy, we developed an ultrasensitive electrochemical biosensor to detect CYP2C19*2 gene. We constructed a novel assay based on cerium dioxide (CeO2)-functionalized carboxyl fullerene (c-C60) supported by Pt nanoparticles (c-C60/CeO2/PtNPs) for signal amplification. Au nanoparticles @ Fe-MIL-88NH2 (AuNPs@Fe-MOFs) were synthesized by one-step method as the support platform to enhance the conductivity and immobilize more biotin-modified capture probe (bio-CP) through the superior affinity and specificity between streptavidin and biotin. c-C60/CeO2/PtNPs were labeled with signal probe to form the signal label. After the sandwich reaction of CYP2C19*2 gene between capture probe and the signal label, a distinguishing electrochemical signal from the catalysis of H2O2 by signal label would be observed. Amperometry was applied to record electrochemical signals. Under optimized conditions, the approach showed a good linear dependence between current and the logarithm of CYP2C19*2 gene concentrations in the range of 1 fM to 50nM with a low detection limit of 0.33fM (S/N = 3). The proposed method showed good specificity to target DNA compared with possible interfering substances. More importantly, the fabricated biosensor achieved accurate quantitative detection of CYP2C19*2 gene in human serum samples demonstrated by excellent correlations with standard DNA sequencing and provided a promising strategy for electrochemical biosensor detection of other gene mutations.

CYP450 Genotype/Phenotype Concordance in Mexican Amerindian Indigenous Populations-Where to from Here for Global Precision Medicine?

Global precision medicine demands characterization of drug metabolism and phenotype variation in diverse populations, including the indigenous societies. A related question is the extent to which CYP450 drug metabolizing enzyme genotype and phenotype data are concordant and whether they can be used interchangeably. These issues are increasingly debated as precision medicine continues to expand as a popular research topic worldwide. We report here the first study in clinically relevant CYP450 drug metabolism phenotypes and genotypes in Mexican Amerindian indigenous subjects. In a large sample of 450 unrelated and medication free Mexican Amerindian indigenous healthy persons from four Mexican states (Chihuahua, Durango, Nayarit, and Sonora), we performed multiplexed phenotyping for the CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 drug metabolizing enzymes using the CEIBA cocktail and genotyped the same pathways for functional polymorphic variation. Remarkable interindividual variability was found for the actual drug metabolizing capacity of all the enzymes analyzed, and, more specifically, the metabolic ratios calculated were significantly different across individuals with different number of active alleles for CYP2C9, CYP2C19, and CYP2D6. The drug metabolizing capacity "predicted" from the genotype determined was not in accordance with the actual capacity "measured" by phenotyping in several individuals for CYP2C9, CYP2C19, and CYP2D6. Consequently, a more extensive genotyping of the main CYP enzymes, including rare variants, together with the analysis of the actual drug metabolizing capacity using an appropriate phenotyping approach will add valuable information for accurate drug metabolism studies, especially useful in understudied populations such as Mexican Amerindians. In sum, this study demonstrates that current personalized medicine strategies based on "predicted" phenotype from genotyping of alleles with high frequency in European populations are not adequate for Mestizos and Native American populations.

Effects of Dual-Dose Clopidogrel, Clopidogrel Combined with Tongxinluo Capsule, and Ticagrelor on Patients with Coronary Heart Disease and CYP2C19*2 Gene Mutation After Percutaneous Coronary Interventions (PCI).

BACKGROUND In recent years, genetic factors have attracted research interest as important predisposing factors for cardiovascular susceptibility. This study aimed to investigate the influences of dual-dose clopidogrel, clopidogrel combined with tongxinluo, and ticagrelor on the platelet activity and MACE events of patients with CYP2C19*2 gene function deficiency and poor clopidogrel response after PCI. MATERIAL AND METHODS We selected 458 patients with coronary heart disease undergoing PCI, and the genotype of CYP2C19*2 was detected by TaqMan real-time PCR. We finally enrolled 212 patients and divided them into 4 groups: a standard anti-platelet group of 46 patients, a clopidogrel double-dose group of 50 cases, a clopidogrel combined with tongxinluo group of 59 cases, and a ticagrelor group of 57. The platelet inhibition rate was detected by TEG. We analyzed and compared differences in platelet activity and the occurrence of MACE events in these 4 groups at different follow-up times. RESULTS The results showed that inhibition of platelet aggregation was better in the double-dose clopidogrel group, the clopidogrel combined with tongxinluo group, and the ticagrelor group than in the regular-dose clopidogrel group, and ticagrelor was the best. We also found that the total incidence of MACE was much lower in the double-dose clopidogrel group, the clopidogrel combined with tongxinluo group, and the ticagrelor group, while the incidence of hemorrhage in the ticagrelor group was higher. CONCLUSIONS Adjusting the dose or combining with other drugs improves the efficacy of anti-platelet therapy and reduces the incidence of ischemic events after PCI.

The Use of Human Liver Cell Model and Cytochrome P450 Substrate-Inhibitor Panel for Studies of Dasatinib and Warfarin Interactions.

The possibility of interactions between warfarin and dasatinib and their interactions with other drugs metabolized by cytochrome P450 isoform CYP3A4 was demonstrated using a previously created cytochrome P450 substrate-inhibitor panel for preclinical in vitro studies of drug biotransformation on a 3D histotypical microfluidic cell model of human liver (liver-on-a-chip technology). Dasatinib and warfarin are inhibitors of CYP2C19 isoform and hence, can interfere the drugs metabolized by this isoform. Our findings are in line with the data obtained on primary culture of human hepatocytes and suggest that the model can be used in preclinical in vitro studies of drugs.

Rifabutin-based Fourth and Fifth-line Rescue Therapy in Patients with for Helicobacter pylori Eradication Failure.

BACKGROUND/AIMS: Optimized regimen has not yet been established for failures of multiple Helicobacter pylori (H. pylori) eradication. Hence, we aimed to evaluate the efficacy of rifabutin-based rescue therapy, at least after three eradication failures. METHODS: Twelve patients, who failed in the treatment for H. pylori eradication at least three times, were consecutively enrolled between 2007 and 2015 at Seoul National University Bundang Hospital. The rifabutin-based rescue regimen was consisted of proton pump inhibitor (PPI), rifabutin (150 mg b.i.d.), and amoxicillin (1 g b.i.d.), given for 7 or 14 days. MIC concentration test by the agar dilution method was performed on six patients prior to rifabutin-based rescue therapy. RESULTS: One patient did not take this regimen, and per-protocol (PP) analysis was performed in 11 patients. The overall eradication rate by intention-to-treat and PP analysis with rifabutin-based rescue therapy was 50.0% (6/12 patients) and 54.5% (6/11 patients), respectively. There was no difference of the eradication rate depending on the underlying disease, smoking, alcohol, number of previous eradication failures, and CYP2C19 genotype. All of the six patients were susceptible to rifabutin, but only three of them succeeded in eradicating with H. pylori. Side effects occurred in two patients (18.2%), and compliance was 90.9%. CONCLUSIONS: Even the eradication rate of rifabutin-based rescue therapy was not very good. Rifabutin-based rescue therapy could be considered as a rescue therapy, perhaps as the fourth or the fifth-line treatment option. No correlation of rifabutin sensitivity with eradication success rate of H. pylori suggests that frequent administration of high dose PPI and amoxicillin might be important.

[Correlation between CYP2C19 Gene Polymorphism with Clopidogrel Resistance and Distribution of Chinese Medicine Syndrome in 229 Acute Coronary Syndrome Patients].

Objective To observe correlation between CYP2C19 *2/CYP2C19 *3 gene polymorphism with clopidogrel resistance and distribution of Chinese medicine ( CM) syndrome in acute coronary syndrome (ACS) population. Methods Peripheral blood was collected from 229 ACS patients from June 2014 to March 2015. DNAs were extracted, amplified, and sequenced. Correlations between CYP2C19 *2/CYP2Cl9 *3 gene polymorphisms and clopidogrel resistance/distribution of CM syndrome were analyzed. Gene frequency and allele frequency were tested using gene counting and one-sample K-S test. Correlation between gene types and distribution of CM syndrome was tested by Pearson corre- lation test. Results (1) The CYP2C19 *2 polymorphism distribution: CYP2C19 *2(A/A) (mutant homozygous) 12 cases (5. 2%) ; CYP2C19 * 2 ( G/A ) ( mutant heterozygote ) 93 cases (40. 6%), and CYP2C19 *2 (G/G) (normal homozygous) 124 cases (54. 2%). The mutant allele frequency was 0. 255. (2) The CYP2C19 *3 polymorphism distribution: CYP2C19 *3 (A/A) 0 case (0) ; CYP2C19 *3 (G/A) 26 cases (11. 4%), and CYP2C19 *3 (G/G) 203 cases (88. 6%). The mutant allele frequency was 0. 056. (3) Correlation between CYP2C19 gene polymorphism and clopidogrel resistance: Clopidogrel resistance was more liable to occur in mutant homozygous than in mutant heterozygote and normal homozygous (R =0. 30, P <0. 01). Clopidogrel resistance was more liable to occur in mutant heterozygote than in normal homozygous (R =0. 34, P <0. 01). (4) Among the 229 patients, the CM syndrome distribution were distributed as follows. Blockage of Xin vessels syndrome (BXVS, 33 cases, 14. 41%) ; qi deficiency blood stasis syndrome (QDBSS, 51 cases, 22. 27%) ; qi stagnation blood stasis syndrome (QSBSS, 92 cases, 40.18%) ; phlegm obstructing Xin vessel syndrome (POXVS, 17 cases, 7. 42%) ; yin-cold coag- ulation syndrome (YCCS, 8 cases, 3. 49%) ; qi-yin deficiency syndrome (QYDS, 13 cases, 5.68%) ; Xin-Shen yin deficiency syndrome (XSYDS, 5 cases, 2.18%), yang and qi deficiency syndrome (YQDS, 10 cases, 4. 37%). (5) CYP2C19 *2 gene type was significantly correlated with syndrome typing of CM (R =0. 26, P <0. 01). Mutant homozygous and most mutant heterozygote patients were syndrome typed as QDBSS. Conclusions The polymorphism of CYP2C19 was closely correlated with clopidogrel resist- ance in 229 ACS patients. Its occurrence rate was correlated with CYP2C19 *2/CYP2C19 *3 gene muta- tion frequency. Blood stasis syndrome ( QSBSS, QDBSS, BXVS) were main syndromes of ACS. Be- sides, QSBSS was obviously higher than the rest syndrome types. The polymorphism of CYP2C19 * 2 was correlated with syndrome typing of CM. CYP2C19 *2 gene defect mostly existed in QSBSS.

CYP2C19 LOF and GOF-Guided Antiplatelet Therapy in Patients with Acute Coronary Syndrome: A Cost-Effectiveness Analysis.

PURPOSE: This study aimed to examine the cost-effectiveness of CYP2C19 loss-of-function and gain-of-function allele guided (LOF/GOF-guided) antiplatelet therapy in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). METHODS: A life-long decision-analytic model was designed to simulate outcomes of three strategies: universal clopidogrel (75 mg daily), universal alternative P2Y12 inhibitor (prasugrel 10 mg daily or ticagrelor 90 mg twice daily), and LOF/GOF-guided therapy (LOF/GOF allele carriers receiving alternative P2Y12 inhibitor, wild-type patients receiving clopidogrel). Model outcomes included clinical event rates, quality-adjusted life-years (QALYs) gained and direct medical costs from perspective of US healthcare provider. RESULTS: Base-case analysis found nonfatal myocardial infarction (5.62%) and stent thrombosis (1.2%) to be the lowest in universal alternative P2Y12 inhibitor arm, whereas nonfatal stroke (0.72%), cardiovascular death (2.42%), and major bleeding (2.73%) were lowest in LOF/GOF-guided group. LOF/GOF-guided arm gained the highest QALYs (7.5301 QALYs) at lowest life-long cost (USD 76,450). One-way sensitivity analysis showed base-case results were subject to the hazard ratio of cardiovascular death in carriers versus non-carriers of LOF allele and hazard ratio of cardiovascular death in non-carriers of LOF allele versus general patients. In probabilistic sensitivity analysis of 10,000 Monte Carlo simulations, LOF/GOF-guided therapy, universal alternative P2Y12 inhibitor, and universal clopidogrel were the preferred strategy (willingness-to-pay threshold = 50,000 USD/QALY) in 99.07%, 0.04%, and 0.89% of time, respectively. CONCLUSIONS: Using both CYP2C19 GOF and LOF alleles to select antiplatelet therapy appears to be the preferred antiplatelet strategy over universal clopidogrel and universal alternative P2Y12 inhibitor therapy for ACS patients with PCI.

Up-Regulation of CYP2C19 Expression by BuChang NaoXinTong via PXR Activation in HepG2 Cells.

BACKGROUND: Cytochrome P450 2C19 (CYP2C19) is an important drug-metabolizing enzyme (DME), which is responsible for the biotransformation of several kinds of drugs such as proton pump inhibitors, platelet aggregation inhibitors and antidepressants. Previous studies showed that Buchang NaoXinTong capsules (NXT) increased the CYP2C19 metabolic activity in vitro and enhanced the antiplatelet effect of clopidogrel in vivo. However, the underlying molecular mechanism remained unclear. In the present study, we examined whether Pregnane X receptor (PXR) plays a role in NXT-mediated regulation of CYP2C19 expression. METHODS: We applied luciferase assays, real-time quantitative PCR (qPCR), Western blotting and cell-based analysis of metabolic activity experiments to investigate the NXT regulatory effects on the CYP2C19 promoter activity, the mRNA/ protein expression and the metabolic activity. RESULTS: Our results demonstrated that NXT significantly increased the CYP2C19 promoter activity when co-transfected with PXR in HepG2 cells. Mutations in PXR responsive element abolished the NXT inductive effects on the CYP2C19 promoter transcription. Additionally, NXT incubation (150 and 250µg/mL) also markedly up-regulated endogenous CYP2C19 mRNA and protein levels in PXR-transfected HepG2 cells. Correspondingly, NXT leaded to a significant enhancement of the CYP2C19 catalytic activity in PXR-transfected HepG2 cells. CONCLUSION: In summary, this is the first study to suggest that NXT could induce CYP2C19 expression via PXR activation.

Antibiotic resistance and CYP2C19 polymorphisms affect the efficacy of concomitant therapies for Helicobacter pylori infection: an open-label, randomized, single-centre clinical trial.

OBJECTIVES: We evaluate the efficacy of concomitant therapy for Helicobacter pylori infection and the associated factors that influence it in China, where it has not previously been investigated. METHODS: In this prospective study, 374 consecutive patients with H. pylori infection were randomly assigned to 10 day regimens of concomitant therapy with different proton pump inhibitors: esomeprazole (20 mg)/omeprazole (20 mg), amoxicillin (1000 mg), clarithromycin (500 mg) and metronidazole (400 mg). All drugs were administered twice daily. A [(13)C]urea breath test was performed at least 4 weeks after the completion of treatment. Gene polymorphisms and antimicrobial susceptibility were determined. RESULTS: A total of 374 patients with active, uncomplicated duodenal ulcer disease were enrolled in the study (187 cases in each group). The overall eradication rate resulting from concomitant therapy was 90.7% (PP) and 86.1% (ITT) and the eradication rate was significantly higher in the group that received an esomeprazole-based regimen compared with the group that received an omeprazole-based regimen [95.4% versus 86.0%, respectively, P = 0.003 (PP) and 89.8% versus 82.4%, P = 0.036 (ITT), respectively]. Moreover, the omeprazole-based regimen was an independent risk factor for treatment failure (P = 0.039), as were CYP2C19 extensive metabolizer (P = 0.005), clarithromycin (P = 0.000) and metronidazole resistance (P = 0.000). In addition, CYP2C19 polymorphisms and antibiotic resistance had a synergistic effect on eradication rates. The majority of side effects were mild and none was serious. CONCLUSIONS: The 10 day concomitant therapy yielded an eradication rate of nearly 90%. Antibiotic resistance, CYP2C19 polymorphisms and their interactions were closely associated with regimen efficacy.

Levofloxacin, bismuth, amoxicillin and esomeprazole as second-line Helicobacter pylori therapy after failure of non-bismuth quadruple therapy.

BACKGROUND: The best rescue therapy for Helicobacter pylori (H. pylori) infection following failure of non-bismuth quadruple therapy (NBQT) remains unanswered. AIMS: To determine the efficacy, safety and compliance of levofloxacin, bismuth, amoxicillin and esomeprazole (LBAE) regimen following failure of NBQT. METHODS: 132 patients with H. pylori infection refractory to first-line NBQT received LBAE regimen (levofloxacin 500mg once/day, bismuth potassium citrate 220mg twice/day, amoxicillin 1000mg twice/day and esomeprazole 20mg twice/day for 14 days). Gastric mucosal biopsy was obtained for H. pylori culture, antimicrobial sensitivity test and cytochrome P450 isoenzyme 2C19 polymorphism analysis. RESULTS: LBAE therapy achieved eradication rates of 73.5% [95% confidence intervals (CI) 65.9-81.1%] in intention-to-treat and 78.5% (71.1-85.9%) in per-protocol analyses in patients with high antibiotic resistance (amoxicillin 8.3%, clarithromycin 55.6%, metronidazole 73.6% and levofloxacin 36.1%). Adverse effects were found in 19.2% and compliance in 96.1% of the treated patients. Multivariate analyses identified levofloxacin resistance [odds ratio (OR) 7.183, 95% CI 1.616-31.914, P=0.010] and history of quinolone intake (4.844, 1.174-19.983, P=0.029) as independent predictors of treatment failure. The eradication rate of patients with dual amoxicillin and levofloxacin resistance was significantly decreased (33.3%, P=0.006). CONCLUSIONS: In populations with high levofloxacin resistance, 14-day second-line LBAE regimen resulted in an unsatisfactory efficacy in patients resistant to NBQT despite good safety and compliance.