Efficacy and safety of tenofovir alafenamide in patients with chronic hepatitis B exhibiting suboptimal response to entecavir.

BACKGROUND: Entecavir (ETV) is a potent and safe antiviral agent for patients with chronic hepatitis B (CHB); however, some patients may exhibit suboptimal response or resistance to ETV. Tenofovir alafenamide (TAF) is a novel tenofovir prodrug with improved pharmacokinetics and reduced renal and bone toxicity compared with tenofovir disoproxil fumarate. AIM: To evaluate the efficacy and safety of switching from ETV to TAF in patients with CHB exhibiting suboptimal response to ETV. METHODS: A total of 60 patients with CHB who had been treated with ETV for at least 12 mo and had persistent or recurrent viremia [Hepatitis B virus (HBV) DNA ≥ 20 IU/mL] or partial virologic response (HBV DNA < 20 IU/mL, but detectable) were enrolled in the study. The patients were randomly assigned to either continue ETV (0.5 mg) daily or switch to TAF (25 mg) daily for 48 wk. The primary endpoint was the proportion of patients who achieved a virologic response (HBV DNA level < 20 IU/mL) at week 48. Secondary endpoints included changes in serum alanine aminotransferase (ALT), hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), and anti-HBe levels, and renal and bone safety parameters. RESULTS: At week 48, the proportion of patients who achieved a virologic response was significantly higher in the TAF group than in the ETV group (93.3% vs 66.7%, P = 0.012). The mean reduction in HBV DNA from baseline was also significantly greater in the TAF group than in the ETV group (-3.8 vs -2.4 Log10 IU/mL, P < 0.001). The rates of ALT normalization, HBeAg loss, HBeAg seroconversion, and HBsAg loss were not found to significantly differ between the two groups. None of the patients developed genotypic resistance to ETV or TAF. Both drugs were well tolerated, with no serious adverse events or discontinuations caused by adverse events. No significant changes were observed in the estimated glomerular filtration rate, serum creatinine level, or urine protein-to-creatinine ratio in either group. The TAF group had a significantly lower decrease in bone mineral density at the lumbar spine and hip than the ETV group (-0.8% vs -2.1%, P = 0.004; -0.6% vs -1.8%, P = 0.007, respectively). CONCLUSION: Switching from ETV to TAF is effective and safe for patients with CHB exhibiting a suboptimal response to ETV and may prevent further viral resistance and reduce renal and bone toxicity.

Two Approaches for Evaluating the Effects of Galangin on the Activities and mRNA Expression of Seven CYP450.

Galangin is a marker compound of honey and Alpinia officinarum Hance that exhibits great potential for anti-microbial, anti-diabetic, anti-obesity, anti-tumour and anti-inflammatory applications. Galangin is frequently consumed in combination with common clinical drugs. Here, we evaluated the effects of galangin on cytochrome P450 (CYP)-mediated metabolism, using two different approaches, to predict drug⁻drug interactions. Male Sprague Dawley rats were administered galangin daily for 8 weeks. A "cocktail-probes" approach was employed to evaluate the activities of different CYP450 enzymes. Blood samples of seven probe drugs were analysed using liquid chromatography-tandem mass spectrometry in positive and negative electrospray-ionisation modes. Pharmacokinetic parameters were calculated to identify statistical differences. CYP mRNA-expression levels were investigated in real-time quantitative polymerase chain reaction experiments. The galangin-treated group showed significantly decreased AUC0⁻∞ and Cmax values for CYP1A2, and CYP2B3. The galangin-treated group showed significantly increased AUC0⁻∞ and Cmax values for CYP2C13 and CYP3A1. No significant influences were observed in the pharmacokinetic profiles of CYP2C11, CYP2D4 and CYP2E1. The mRNA-expression results were consistent with the pharmacokinetic results. Thus, CYP450 enzyme activities may be altered by long-term galangin administration, suggesting galangin to be a promising candidate molecule for enhancing oral drug bioavailability and chemoprevention and reversing multidrug resistance.

Insulin-like growth factor binding protein-related protein 1 contributes to hepatic fibrogenesis.

OBJECTIVE: The aim of this study was to investigate the role of insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) in the development of hepatic fibrogenesis in experimental disease models and human liver samples. METHODS: Cellular distribution patterns of IGFBP-rP1 were assessed by immunohistochemistry in fibrotic and cirrhotic human liver specimens. Gene silencing of IGFBP-rP1 was performed on cultured hepatic stellate cells (HSCs) by small interfering RNA (siRNA), and the silencing effect was determined by quantitative real-time polymerase chain reaction (PCR) and Western blot. We also determined the effects of siRNA-mediated gene silencing of IGFBP-rP1 on the production of extracellular matrix (ECM) components by Western blot. The expression of ECM components and transforming growth factor (TGF)-ß1 was studied by immunohistochemistry and Western blot in C57BL/6 wild-type mice treated with recombinant IGFBP-rP1 (rIGFBP-rP1). RESULTS: Expression of IGFBP-rP1 was significantly elevated in fibrotic and cirrhotic human liver specimens, and this increase was positively correlated with the number of collagen fibers observed. siRNA-mediated gene silencing of IGFBP-rP1 resulted in significantly decreased levels of collagen I and fibronectin in HSCs. Moreover, IGFBP-rP1 overexpression significantly increased the production of collagen, fibronectin and TGF-ß1 in rIGFBP-rP1-treated mice. CONCLUSIONS: IGFBP-rP1 contributes to the development of liver fibrosis and may be a novel molecule involved in the progression of hepatic fibrogenesis.

[The diagnostic value of multichannel intraluminal esophageal impedance and pH monitoring in gastroesophageal reflux-related cough].

OBJECTIVE: To evaluate the diagnostic value and limitation of multichannel intraluminal esophageal impedance and pH (MII-pH) monitoring on the diagnosis of gastroesophageal reflux-related chronic cough (GERC). METHODS: The patients with suspicious GERC consecutively referred to our respiratory clinic between May 2010 and July 2011 underwent a MII-pH monitoring, and received anti-reflux drug therapy, irrespective of the laboratory findings. Chronic cough due to gastroesophageal reflux was determined when there was a favorable response to anti-reflux therapy. Then, the sensitivity, specificity, false positive and negative rate, total consistence, positively and negatively predictive value, the area under the curve of ROC and the Kappa value of the laboratory investigation were calculated for the diagnosis of GERC. RESULTS: During the research period, 56 patients completed MII-pH monitoring. Among them, the abnormal reflux was found in 35 patients, and GERC was finally confirmed in 30 patients (85.7%) including 25 patients (83.3%) due to acid reflux and 5 patients (16.7%) due to non-acid reflux. In the remaining 21 patients with normal reflux episodes, 6 patients (28.6%) could be explained by non-acid reflux for their cough because of a relatively predominant weakly acid reflux and favorable response to empirical anti-reflux therapy. For the diagnosis of GERC, MII-pH monitoring had the sensitivity of 83.3%, the specificity of 75.0%, false positive rate of 25.0%, false negative rate of 16.7%, total consistence of 80.4%, positive predictive value of 85.7%, negative predictive value of 71.4%, the area under the curve of ROC of 0.792 and Kappa value of 0.577 respectively. CONCLUSION: MII-pH is a sensitive and reliable tool for the diagnosis of GERC due to its ability to detect both acid and non-acid reflux.

Discrepancy between presumptive and definite causes of chronic cough.

BACKGROUND: The current diagnostic algorithms for chronic cough require the establishment of the primary presumptive causes followed by the confirmation of diagnosis with the specific therapies. The aim of the study was to investigate the discrepancy between presumptive and definite causes and its clinical implication. METHODS: A total of 109 patients with chronic cough underwent laboratory investigations to identify the cause of cough; including sinus computerized tomography (if needed), histamine bronchial provocation, induced sputum cytology and 24-hour esophageal pH or multi-channel intraluminal impedance combined with pH monitoring. The presumptive causes were confirmed by treating them sequentially. The difference between presumptive and definite causes of chronic cough was compared. RESULTS: Single cause was more frequent in the definite diagnosis than in the presumptive diagnosis (78.9% vs. 54.1%, χ(2) = 15.01, P = 0.0001). In contrast, multiple causes were significantly fewer in definite diagnosis than in the presumptive diagnosis (15.6% vs. 37.6%, χ(2) = 13.53, P = 0.0002). There was a discrepancy between definite and presumptive causes in 30 patients (27.5%). Compared with the presumptive causes, definite upper airway cough syndrome (24.8% vs. 11.9%, χ(2) = 6.0, P = 0.01) and gastroesophageal reflux disease (6.4% vs. 0, χ(2) = 7.23, P = 0.007) was more frequent as a single cause of chronic cough while cough variant asthma plus gastroesophageal reflux disease (3.7% vs. 11.9%, χ(2) = 5.17, P = 0.02) and upper airway cough syndrome plus nonasthmatic eosinophilic bronchitis (0 vs. 9.2%, χ(2) = 10.48, P = 0.001) were fewer as multiple causes of chronic cough. CONCLUSIONS: A discrepancy was common between presumptive and definite causes of chronic cough. To treat presumptive causes sequentially may be a suitable solution for avoidance of erroneous multiple causes and possible over-treatment.