Pharmacogenomic study of gemcitabine efficacy in patients with metastatic pancreatic cancer: A multicenter, prospective, observational cohort study (GENESECT study).

BACKGROUND: Genetic polymorphisms of molecules are known to cause individual differences in the therapeutic efficacy of anticancer drugs. However, to date, germline mutations (but not somatic mutations) for anticancer drugs have not been adequately studied. The objective of this study was to investigate the association between germline polymorphisms of gemcitabine metabolic and transporter genes with carbohydrate antigen 19-9 (CA 19-9) response (decrease ≥50% from the pretreatment level at 8 weeks) and overall survival (OS) in patients with metastatic pancreatic cancer who receive gemcitabine-based chemotherapy. METHODS: This multicenter, prospective, observational study enrolled patients with metastatic pancreatic cancer patients who were receiving gemcitabine monotherapy or gemcitabine plus nanoparticle albumin-bound paclitaxel combination chemotherapy. Thirteen polymorphisms that may be involved in gemcitabine responsiveness were genotyped, and univariate and multivariate logistic regression analyses were used to determine the association of these genotypes with CA 19-9 response and OS. The significance level was set at 5%. RESULTS: In total, 180 patients from 11 hospitals in Japan were registered, and 159 patients whose CA 19-9 response could be assessed were included in the final analysis. Patients who had a CA 19-9 response had significantly longer OS (372 vs. 241 days; p = .007). RRM1 2464A>G and RRM2 175T>G polymorphisms suggested a weak association with CA 19-9 response and OS, but it was not statistically significant. COX-2 -765G>C polymorphism did not significantly correlate with CA 19-9 response but was significantly associated with OS (hazard ratio, 2.031; p = .019). CONCLUSIONS: Genetic polymorphisms from the pharmacokinetics of gemcitabine did not indicate a significant association with efficacy, but COX-2 polymorphisms involved in tumor cell proliferation might affect OS.

A multicenter phase II trial of the triplet antiemetic therapy with palonosetron, aprepitant, and olanzapine for a cisplatin-containing regimen. - PATROL-I.

Dexamethasone is one of the key antiemetic agents and is widely used even now. However, dexamethasone has been associated with several adverse reactions even after short-term administration. Therefore, developing a steroid-free antiemetic regimen is an important issue to consider. Thus, the purpose of this study was to investigate the efficacy and safety of palonosetron, aprepitant, and olanzapine in a multi-institutional phase II study. Chemotherapy-naive patients scheduled to receive cisplatin were enrolled and evaluated for the occurrence of chemotherapy-induced nausea and vomiting during 120 h after chemotherapy. The primary endpoint of the study was total control (TC) in the overall phase. The key secondary endpoint was complete response (CR), which was assessed in the acute, delayed, and overall phase, respectively. Adverse events were evaluated according to the Common Terminology Criteria for Adverse Events. Eighty-five patients were enrolled from 8 centers in Japan, of which 83 were evaluable for analyses. The percentage of patients who achieved TC during the overall phase was 31.3%. CR was achieved in 61.4%, 84.3%, and 65.1% of patients during the overall, acute, and delayed phases, respectively. The most frequently reported adverse event was anorexia. The primary endpoint was below the threshold and we could not find benefit in the dexamethasone-free regimen, but CR during the overall phase was similar to that of the conventional three-drug regimen. This antiemetic regimen without dexamethasone might be an option for patients for whom corticosteroids should not be an active application.

Chemotherapy-induced neutropenia as a prognostic factor in patients with extensive-stage small cell lung cancer.

PURPOSE: Chemotherapy-induced neutropenia (CIN) is a dose-limiting factor for cytotoxic chemotherapy, but recently, it was suggested that CIN contributes to prolonged survival. In this study, we examined the association between severe CIN and survival and determined whether CIN affected survival in patients with extensive-stage small cell lung cancer (ES-SCLC). METHODS: The medical records from 214 patients with ES-SCLC treated with etoposide or irinotecan in combination with cisplatin (EP/IP) between 2012 and 2016 were collected and retrospectively analyzed. Landmark analysis was performed at the end of cycle 4, and the relationship between severe CIN and survival was determined by a log-rank test. In addition, a multivariate analysis using the COX proportional hazard model was performed to identify independent predictive factors. The Landmark analysis included 102 patients in the IP group and 47 patients in the EP group. RESULTS: No significant difference was found between grades 0-3 and grade 4 neutropenia and overall survival (OS) in the EP group (P = 0.57). Contrariwise, for the IP patients, the median OS was 444 days for grades 0-3 and 633 days for grade 4 neutropenia, which was significantly longer for patients who developed grade 4 neutropenia (P = 0.03). Multivariate analysis adjusted for potential factors revealed that the development of grade 4 CIN was identified as a significant predictor of longer OS (hazard ratio [HR], 0.50; 95% confidence interval (CI), 0.28-0.87, P = 0.015). CONCLUSION: The results indicated that the development of severe CIN with IP therapy is associated with prolonged OS.

Relevance of pharmacogenetic polymorphisms with response to docetaxel, cisplatin, and 5-fluorouracil chemotherapy in esophageal cancer.

PURPOSE: Docetaxel, cisplatin, and 5-fluorouracil (DCF) have high response rates, but severe neutropenia is frequently observed. The occurrence of neutropenia is associated with high histological response in solid tumors, and it might be associated with tumor shrinkage after DCF therapy. This study aimed to determine the genetic polymorphisms involved in the clinical response to preoperative DCF therapy in esophageal cancer patients. METHODS: We included 56 patients with measurable lesions who received preoperative DCF therapy for esophageal cancer. Twenty-one genetic polymorphisms were analyzed, and univariate logistic regression analysis was used to evaluate the association between genetic polymorphisms and tumor shrinkage. A multivariate logistic regression analysis adjusted for T category and tumor location and a univariate analysis for potential genetic factors with P values < 0.05 were performed to explore the predictive factors and to estimate odds ratios and their 95% confidence intervals. RESULTS: No patient achieved a complete response, whereas 20 patients achieved a partial response, 31 patients had stable disease, and 5 patients had progressive disease. Although no association was found between pharmacokinetic-related gene polymorphisms, XRCC3 rs17997944 was extracted as the only genetic factor that affected tumor shrinkage (P = 0.033) by univariate analysis. The multivariate analysis adjusted for T category and tumor site also showed that XRCC3 rs1799794: AA was a predictive factor that affected tumor shrinkage (odds ratio, 0.243; 95% confidence interval, 0.065-0.914; P = 0.036). CONLUSIONS: XRCC3 rs1799794, which is involved in homologous recombination, is a genetic factor that affects clinical responses to DCF therapy.

Circulating microRNA-15b-5p as a biomarker for asthma-COPD overlap.

BACKGROUND: It remains unclear how to characterize different subtypes of asthma and chronic obstructive pulmonary disease (COPD). We previously described serum periostin and chitinase-3-like protein 1 (YKL-40) as useful markers for asthma-COPD overlap (ACO). MicroRNAs (miRNAs) are now recognized as markers for identifying the pathophysiological features in several diseases. This study aimed to identify circulating miRNAs that could discriminate patients with ACO from patients with asthma or COPD. METHODS: This study included two independent cohorts. First, we screened 84 miRNAs for expression levels in patients with ACO (n = 6) or asthma (n = 6) using a quantitative real-time PCR array. The miRNAs showing at least a 2-fold difference in the discovery phase were analyzed in 30 patients each with asthma, COPD, or ACO in the replication phase. The diagnostic accuracy was evaluated using the area under the receiver operating characteristic curve (AUROC). RESULTS: Nine miRNAs were identified in the discovery phase. Five of these miRNAs (miR-148a-3p, miR-15b-5p, miR-223-3p, miR-23a-3p, and miR-26b-5p) had lower levels in ACO patients and could discriminate between ACO patients and patients with either asthma or COPD. miR-15b-5p was the most accurate miRNA for the discrimination of patients with ACO (AUROC, 0.71). Moreover, the combined assessment of miR-15b-5p, serum periostin, and YKL-40 (AUROC, 0.80) improved diagnostic accuracy for ACO compared with the combined model of periostin and YKL-40 (AUROC, 0.69). CONCLUSIONS: Circulating miR-15b-5p is a potential marker for identifying patients with ACO. By elucidating the molecular pathways controlled by miRNAs, we may better understand the pathophysiology of ACO.

CYP2C9, VKORC1, and CYP4F2 polymorphisms and pediatric warfarin maintenance dose: a systematic review and meta-analysis.

Studies on the effect of cytochrome P450 2C9 (CYP2C9), vitamin K epoxide reductase complex subunit 1 (VKORC1), and cytochrome P450 4F2 (CYP4F2) polymorphisms on warfarin maintenance dose in children are conflicting. We conducted a systematic review and meta-analysis to evaluate the effect of these polymorphisms on warfarin maintenance dose in children. We searched relevant literature using the MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trial libraries without any language restrictions from their inception to 23 July 2017. Dose differences are expressed as standardized mean difference (SMD) or mean difference (MD) with 95% confidence intervals (CI). This review was registered in the PROSPERO prospective register of systematic reviews (CRD42015016172). We included a total of nine studies (745 participants) in the meta-analysis. Patients with CYP2C9 *1/*2, *1/*3, *2/*2, *2/*3, or *3/*3 required a lower warfarin maintenance dose compared with patients with CYP2C9 *1/*1 (SMD = -0.610, 95% CI: -0.802 to -0.419, I2 = 0%). Patients with VKORC1-1639GA or AA required a lower warfarin maintenance dose compared with patients with VKORC1-1639GG (SMD = -0.666, 95% CI: -0.887 to -0.445, I2 = 33%). However, no associations were observed between CYP4F2 polymorphisms and warfarin maintenance dose (MD = 0.005 mg/kg/day, 95% CI: -0.006 to 0.015, I2 = 0%). These results were not affected by a sensitivity analysis. Our meta-analysis provides evidence that CYP2C9 and VKORC1 variant statuses affect warfarin maintenance dose in children, but not CYP4F2.

A Reversed-Phase Mode LC-MS/MS Method Using a Polysaccharide Chiral Selector for Simultaneous Quantitation of Each Enantiomer of Tramadol and its Metabolites in Human Plasma and Evaluation of CYP-Mediated Stereoselective Demethylation.

BACKGROUND: The enantiomeric pharmacokinetics and metabolism of tramadol and its metabolites have not fully been understood. This study aimed to develop a reversed-phase mode liquid chromatography coupled to a tandem mass spectrometry method for the enantiomeric quantitation of tramadol and its metabolites in human plasma and to evaluate the stereoselective demethylation. METHODS: Racemic tramadol and its metabolites in plasma specimens were separated using a chiral selector coated with cellulose tris(3,5-dimethylphenylcarbamate) on silica gel under a reversed-phase mode. The mass spectrometer ran in the positive ion multiple-reaction monitoring mode. This method was performed to quantify plasma samples from 20 cancer patients treated with oral tramadol. The stereoselective demethylation was evaluated using recombinant cytochrome P450 (CYP) enzymes. RESULTS: The calibration curves of (+)- and (-)-tramadol, (+)- and (-)-O-desmethyltramadol (ODT), and (+)- and (-)-N-desmethyltramadol (NDT) were linear over the plasma concentration ranges of 6.25-800, 1.25-160, and 3.13-400 ng/mL for the respective enantiomers. In the present method, the intra- and inter-day accuracies and imprecisions were 94.2%-108.3% and 0.5%-6.0% for all analytes. The plasma concentrations of (+)-tramadol and NDT were higher than those of (-)-enantiomers. In contrast, no differences were observed between the plasma concentrations of (+)- and (-)-ODT. In the demethylation assay, the O-demethylations of tramadol and NDT by CYP2D6 were (-)-form-selective. CONCLUSIONS: The present method can be useful in the enantiomeric evaluation of tramadol and its metabolites in human plasma. Although CYP2D6 contributed to the stereoselective demethylation of tramadol, remarkable differences between (+)- and (-)-ODT were not observed in the plasma of the cancer patients.

Risk factors associated with chemotherapy-induced nausea and vomiting in the triplet antiemetic regimen including palonosetron or granisetron for cisplatin-based chemotherapy: analysis of a randomized, double-blind controlled trial.

PURPOSE: The triplet antiemetic regimen is recommended for cisplatin-based highly emetogenic chemotherapy, in the current guidelines for antiemetic prophylaxis. Although risk factors related to chemotherapy-induced nausea and vomiting (CINV) have been identified by several prior studies, there are only few studies evaluating risk factors associated with the prophylactic triplet antiemetic therapy, particularly in palonosetron use. The present study aimed to reveal the risk factors related to CINV development in patients receiving cisplatin and to compare CINV risk factors between palonosetron and granisetron use. METHODS: In total, 825 patients in a phase III trial receiving palonosetron with graniestron were evaluated. Multivariate logistic regression models were used to predict risk factors associated with CINV development. Additionally, risk factors associated with CINV development were separately evaluated in each treatment group. RESULTS: Multivariate analysis of the entire study group revealed that sex, age, cisplatin dose, and granisetron use were significant and independent factors affecting CINV development in the overall phase. Similarly, sex and age were risk factors for CINV in both treatment groups. Kaplan-Meier curves classified by each treatment group showed no significant difference between the groups among patients without any risk factors for CINV (P = 0.353). Conversely, complete response rates for patients with at least one risk factor were higher in patients receiving palonosetron (P = 0.049). CONCLUSIONS: This analysis revealed the importance of previously reported CINV risk factors when using triplet antiemetics. Palonosetron might be preferred for patients with at least one risk factor.

Comparison of the Association between Circulating Vitamin D3 Levels and Clinical Outcomes in Patients with Asthma and Chronic Obstructive Pulmonary Disease: A Prospective Observational Study.

Vitamin D has an immune-modulating effect, related to the pathophysiology of asthma and chronic obstructive pulmonary disease (COPD). However, few studies have focused on the difference between patients with asthma and COPD in the association of circulating vitamin D levels with clinical outcomes. We sought to investigate the associations of circulating vitamin D levels with health-related QOL (HR-QOL), severity, and exacerbations. Subjects included 152 asthma patients and 50 COPD patients. We measured plasma concentrations of 25-hydroxyvitamin D3 [25(OH)D3]. HR-QOL was assessed using the EuroQoL 5-Dimension (EQ-5D) and the 12-item Short Form Health Survey (SF-12) scales. Exacerbations were recorded during a one-year follow-up. Associations between plasma 25 (OH)D3 concentrations and outcome variables were evaluated using linear regression. Plasma concentrations of 25(OH)D3 were positively associated with the EQ-5D index value and the SF-12 physical component score in patients with asthma; however, such associations were not observed in patients with COPD. A significant association between severity and plasma concentrations of 25(OH)D3 was found only in patients with COPD. The hazard ratios (95% confidence interval) of plasma 25(OH)D3 concentrations (per 1 ng/mL decrease) for time to first exacerbation was 1.38 (1.10-1.75; p = 0.006) and 0.95 (0.87-1.03; p = 0.179) in patients with COPD and asthma, respectively. Lower concentrations of plasma 25(OH)D3 contributed to lower HR-QOL in patients with asthma, and were associated with severity and risk of future exacerbations in patients with COPD.

Impact of Gene Expression Associated with Glucocorticoid-Induced Transcript 1 (GLCCI1) on Severe Asthma and Future Exacerbation.

Genetic variations in glucocorticoid-induced transcript 1 (GLCCI1) have been associated with the response to corticosteroid treatment. However, the associations of GLCCI1 polymorphisms or gene expression with the prognosis of asthma and pathophysiological factors related to steroid insensitivity remain unclear. We sought to investigate the associations of GLCCI1, nuclear factor (erythroid-derived 2)-like 2 (Nrf2), and histone deacetylase 2 (HDAC2) mRNA expression levels and the GLCCI1 rs37973 polymorphism with asthma severity and future exacerbation in patients with asthma. Subjects included 25 patients with severe asthma and 127 patients with nonsevere asthma. mRNA expression levels in peripheral blood mononuclear cells were measured and evaluated as predictors of severe asthma using receiver operating characteristic (ROC) analysis. The hazard ratios of the mRNA expression levels for time to first exacerbation in the 1-year follow-up period were calculated. GLCCI1, Nrf2, and HDAC2 mRNA expression levels were significantly lower in patients with severe asthma than in patients with nonsevere asthma and could predict severe asthma with an area under the ROC curve of 0.68, 0.71, and 0.65, respectively. In contrast, no relationship was found between the GLCCI1 rs37973 polymorphism and severe asthma. The hazard ratios for asthma exacerbation in patients with low GLCCI1, Nrf2, and HDAC2 mRNA expression levels were 3.24 (95% confidence interval, 1.42-7.40), 3.13 (1.37-7.16), and 2.98 (1.22-7.25), respectively. Patients with severe asthma could be distinguished by lower GLCCI1, Nrf2, and HDAC2 mRNA levels in peripheral blood cells, and all of these gene signatures could predict future asthma exacerbations.

Anti-Idiotype DNA Aptamer Affinity Purification⁻High-Temperature Reversed-Phase Liquid Chromatography: A Simple, Accurate, and Selective Bioanalysis of Bevacizumab.

This study presents a simple, accurate, and selective bioanalytical method of bevacizumab detection from plasma samples based on aptamer affinity purification⁻high-temperature reversed-phased liquid chromatography (HT-RPLC) with fluorescence detection. Bevacizumab in plasma samples was purified using magnetic beads immobilized with an anti-idiotype DNA aptamer for bevacizumab. The purified bevacizumab was separated with HT-RPLC and detected with its native fluorescence. Using aptamer affinity beads, bevacizumab was selectively purified and detected as a single peak in the chromatogram. HT-RPLC achieved good separation for bevacizumab with a sharp peak within 10 min. The calibration curves of the two monoclonal antibodies ranged from 1 to 50 µg/mL and showed good correlation coefficients (r² > 0.999). The limit of detection (LOD) and lower limit of quantification (LLOQ) values for bevacizumab were 0.15 and 0.51 µg/mL, respectively. The proposed method was successfully applied to the bioanalysis of the plasma samples obtained from the patients with lung cancer and may be extended to plan optimal therapeutic programs and for the evaluation of biological equivalencies in the development of biosimilars.

Validation of a Nomogram for Achieving Target Trough Concentration of Vancomycin: Accuracy in Patients With Augmented Renal Function.

BACKGROUND: Adjustment of initial vancomycin (VCM) dosage has been recommended on the basis of the renal function nomogram in therapeutic drug monitoring guidelines in Japan. However, this nomogram has not been clinically validated, and few studies have focused on its usefulness in patients with risk of augmented renal function. Therefore, this study aimed to evaluate the validity of the VCM nomogram and the association between patient conditions related to augmented renal function and its accuracy. METHODS: In this retrospective study, we screened data of 398 patients who received VCM and had estimated glomerular filtration rates ≥30 mL·min·1.73 m. Patients who met nomogram dosing criteria were categorized into a nomogram group, and the associations of age, renal function, and individual conditions such as febrile neutropenia, solid tumor, blood cancer, and brain injury with subtherapeutic concentrations (<10.0 mcg/mL) of VCM were evaluated. RESULTS: In total, 177 patients were categorized into the nomogram group, and 83 (47%), 81 (46%), and 13 patients (7%) had VCM trough concentrations of 10-20, <10, and >20 mcg/mL, respectively. Age <50 years was only significantly associated with subtherapeutic trough concentrations. Specific conditions of patients such as febrile neutropenia, solid tumor, and blood cancer were associated with elevated VCM clearance; however, there was no decline in trough VCM concentrations regardless of the presence of the specific conditions. CONCLUSIONS: The Japanese VCM dosing nomogram was effective in minimizing the number of instances of supratherapeutic VCM serum concentrations; however, it lacked accuracy in achieving target trough concentrations. The accuracy of the nomogram could be enhanced by categorizing patients according to age. Nevertheless, this study provides novel evidence of the usefulness of this nomogram in avoiding subtherapeutic concentrations of VCM in patients with risk factors for augmented renal clearance.

Genetic risk factors for chemotherapy-induced nausea and vomiting in patients with cancer receiving cisplatin-based chemotherapy.

PURPOSE: Younger age and female sex have already been well-known risk factors for chemotherapy-induced nausea and vomiting (CINV), and 30-50% of cancer patients still suffer from CINV. Genetic polymorphisms are suggested to influence antiemetic treatment response. METHODS: This study included a subset of patients previously enrolled in a randomised controlled trial; 156 patients were evaluated. This study aimed to evaluate the role of pharmacogenomic polymorphisms relevant to antiemetic response in patients with cancer receiving cisplatin-based chemotherapy. The study's efficacy endpoint was the proportion of patients with complete response (CR). The study endpoint was evaluated separately in the acute (CR0-24) and delayed (CR24-120) phases. Thirteen polymorphisms were genotyped, and the association of these genotypes with the efficacy of prophylactic antiemetics was then investigated. Confounding variables for the CR were identified using stepwise multivariate logistic regression analysis. Age and sex were included as independent variables by the forced-entry method, and the stepwise method was used to select the pharmacogenomic factors for inclusion as independent variables. RESULTS: Multivariate logistic regression analysis revealed that the ERCC1 8092AA (odds ratio [OR] = 11.25; 95% confidence interval [CI] 1.74-72.71; p = 0.011) and female sex (OR = 3.63; 95% CI 1.14-11.58; p = 0.029) were significant predictors of CR0-24. No significant association of CR24-120 with pharmacogenomic polymorphisms was found via multivariate logistic regression analysis. CONCLUSIONS: ERCC1 polymorphism influenced the extent of CINV control in patients receiving cisplatin-based chemotherapy. TRIAL REGISTRATION: Clinical trial information: UMIN 000009335.

Chemotherapy-induced neutropenia as a prognostic factor in patients with metastatic pancreatic cancer treated with gemcitabine.

PURPOSE: Chemotherapy-induced neutropenia (CIN) is a common side effect of chemotherapy and an important dose-limiting factor. However, an association between CIN development and longer survival was recently reported in several solid cancers. In the present study, we aimed to assess whether CIN could be a prognostic factor and clarify other prognostic factors for patients with metastatic pancreatic cancer. METHODS: We retrospectively analyzed the medical records of 84 patients who received gemcitabine monotherapy as first-line chemotherapy for metastatic pancreatic cancer to assess whether CIN could be a prognostic factor. Potential prognostic factors of survival were examined by univariate and multivariate analyses using the log-rank test and Cox proportional hazard model, respectively. RESULTS: Median survival time was 170 days [95% confidence interval (CI), 147-193] in patients without CIN (grade 0), 301 days (95% CI, 152-450) in patients with grade 1-2 CIN, and 406 days (95% CI, 271-541) in patients with grade 3 CIN. The multivariate analysis revealed that a pretreatment C-reactive protein level of <0.50 mg/dL [hazard ratio (HR), 0.534; 95% CI, 0.323-0.758, P = 0.015] and grade 3 CIN (HR, 0.447; 95% CI, 0.228-0.875, P = 0.019) were independent favorable prognostic factors in patients with metastatic pancreatic cancer treated with gemcitabine. CONCLUSIONS: Neutropenia during chemotherapy was associated with increased survival of patients with metastatic pancreatic cancer. Monitoring of CIN could be used to predict treatment responsiveness.

Augmented Renal Clearance in Patients With Febrile Neutropenia is Associated With Increased Risk for Subtherapeutic Concentrations of Vancomycin.

BACKGROUND: Augmented renal clearance (ARC) has frequently been observed in critically ill patients. The risk factors for ARC in patients, including those in the general ward, and their influences on vancomycin (VCM) treatment remain unclear. The aims of this study were to investigate the risk factors for ARC and to evaluate the influence of ARC on the pharmacokinetic parameters of VCM. METHODS: This study included a total of 292 patients with VCM treatment who had normal serum creatinine concentrations. ARC was defined by an estimated creatinine clearance ≥130 mL·min·1.73 m. The risk factors for ARC were determined with stepwise logistic regression analysis. The pharmacokinetic parameters of VCM were estimated through the Bayesian method using a 2-compartment model. RESULTS: ARC was observed in 48 patients (16.4%). Age ≤65 years [odds ratio (OR): 5.77; 95% CI: 2.89-11.97; P < 0.0001], brain injury (OR: 5.11; 95% CI: 1.49-17.57; P = 0.0086), febrile neutropenia (OR: 2.76; 95% CI: 1.11-6.67; P = 0.0254), and a mean volume of infusion fluid ≥1500 mL/d (OR: 2.53; 95% CI: 1.27-5.16; P = 0.0091) were independent risk factors for the occurrence of ARC. The patients with ARC exhibited higher VCM clearance values than the non-ARC patients. The median trough serum concentrations of VCM were 7.4 (interquartile range: 5.2-11.6) mcg/mL in the ARC patients and 12.2 (8.9-16.3) mcg/mL in the non-ARC patients (P < 0.0001). Subtherapeutic trough concentrations of VCM (<10.0 mcg/mL) were found in 68.8% of the ARC patients and in 32.8% of the non-ARC patients (P < 0.0001). CONCLUSIONS: This observational study investigated the influence of febrile neutropenia on the emergency of ARC for the first time. ARC was strongly associated with VCM pharmacokinetics, and two-thirds of the ARC patients had subtherapeutic VCM concentrations. In patients with ARC, individualized dosing regimens are required to achieve the target trough concentration.

Augmented Renal Clearance in Pediatric Patients With Febrile Neutropenia Associated With Vancomycin Clearance.

BACKGROUND: Vancomycin (VCM) dosage optimization in the early stages of therapy is required to achieve target trough serum concentrations, particularly in critically ill patients. Augmented renal clearance (ARC), commonly characterized by an enhanced renal clearance, has been associated with subtherapeutic concentrations of antibiotics. The aim of this study was to investigate the risk factors including febrile neutropenia for both ARC and VCM clearance in Japanese pediatric patients. METHODS: A total of 109 pediatric patients with normal renal function were included in this observational study. From VCM serum concentrations, individual VCM clearance was estimated by the Bayesian method using a 1-compartment model. Patients were classified on the basis of the presence of febrile neutropenia, cancer, trauma, systemic inflammatory response syndrome, and surgical operation. Risk factors for ARC, as defined by estimated glomerular filtration rate (eGFR) above median value (≥160 mL·min·1.73 m), were evaluated. RESULTS: Febrile neutropenia was only an independent risk factor for ARC (odds ratio, 5.86; 95% confidence interval, 1.98-21.66, P = 0.0030), which was the result of a stepwise multivariate logistic regression analysis. Although univariate analysis demonstrated a significant association of febrile neutropenia with VCM clearance, the significant independent factors of VCM clearance were age and eGFR but not febrile neutropenia, as estimated by the stepwise multivariate linear regression analysis. CONCLUSIONS: This observational study concluded that febrile neutropenia, a significant risk factor for ARC, indirectly influenced VCM clearance towing to an elevated eGFR. Cancer, trauma, systemic inflammatory response syndrome, and surgical operation were not significantly associated with ARC; however, more studies are needed to validate this observation. Adjustment of the initial dosage of VCM is required for achieving optimal therapeutic concentrations in pediatric patients with febrile neutropenia.

Risk factors for hypernatremia in patients with short- and long-term tolvaptan treatment.

PURPOSE: The long-term efficacy of tolvaptan, a vasopressin V2 receptor antagonist, has been reported. However, the safety of long-term treatment remains to be fully elucidated. We assessed the safety profile of tolvaptan with respect to hypernatremia. METHODS: This retrospective study included 371 patients treated with tolvaptan. Risk factors for hypernatremia (serum sodium concentration ≥147 mEq/L) were determined. RESULTS: Hypernatremia occurred in 95 patients (25.6 %), of whom 71 (19.1 %) developed hypernatremia within 7 days of tolvaptan treatment (early onset). Stepwise logistic regression analysis demonstrated that baseline serum sodium ≥140 mEq/L, an initial tolvaptan dosage >7.5 mg, and a BUN/serum creatinine ratio ≥20 were independent risk factors for early onset of hypernatremia. Tolvaptan was prescribed for more than 7 days to 233 patients, of whom 123 were administrated tolvaptan for more than 1 month. Hypernatremia occurred in 24 of these patients (10.3 %) (late onset). Predictive factors for late onset of hypernatremia were an average daily dosage of tolvaptan >7.5 mg and age ≥75 years. CONCLUSIONS: A daily dosage of 7.5 mg or less was recommended to prevent hypernatremia in short- as well as long-term tolvaptan treatment, and mainly elderly patients were at risk for hypernatremia.

Factors that influence the pharmacokinetics of lamotrigine in Japanese patients with epilepsy.

PURPOSE: Lamotrigine (LTG) is used to treat epilepsy. The variability of LTG pharmacokinetics among individuals may be attributed to polymorphisms in the genes of uridine diphosphate glucuronosyltransferases (UGTs) 1A4 and UGT2B7 and/or combination with other drugs. In this study, we evaluated the association between LTG concentrations and patient characteristics such as genetic polymorphisms and the co-administration of antiepileptic drugs. METHODS: We recruited 122 patients with epilepsy. LTG concentrations were measured in blood samples from each patient under steady-state condition. We assessed the influence of multiple factors on LTG concentrations and derived a formula for predicting LTG concentrations using multiple linear regression analysis. RESULTS: We derived a formula to predict LTG concentrations that considers the daily dose of LTG, body weight, valproic acid concentration, phenytoin co-administration, and the co-administration of phenobarbital and/or carbamazepine as well as UGT1A4 142T>G and UGT2B7 -161C>T polymorphisms (adjusted coefficients of determination R (2) = 0.734). Furthermore, we used this formula to reveal a strong positive correlation between measured and predicted LTG concentrations (r (2) = 0.76, p < 0.001). CONCLUSION: We derived a formula that will be useful in clinical practice for predicting LTG concentrations in patients with epilepsy.

Influence of Genetic Polymorphisms and Concomitant Anxiolytic Doses on Antidepressant Maintenance Doses in Japanese Patients with Depression.

To prevent recurrent depression, patients should ideally continue treatment for >6 months with the antidepressant dose that effectively suppressed acute depressive symptoms. However, there are inter-individual differences in the antidepressant doses required to achieve response and maintenance. Therefore, this study was conducted to examine the role of clinical features, including genetic polymorphisms, on the antidepressant dose required for maintenance therapy in 82 Japanese patients with depression. We calculated the antidepressant dose using the imipramine equivalent scale and the dose of concomitant anxiolytics and hypnotics using the diazepam equivalent scale. The 82 participants were classified into two groups based on the median imipramine equivalent dose, and we examined the influence of patient characteristics and the presence of genetic polymorphisms of brain-derived neurotropic factor (BDNF; rs6265) and cyclic adenosine monophosphate responsive element-binding protein 1 (CREB1; rs2253306, rs4675690, rs769963) on the antidepressant maintenance dose. Using a multivariate logistic regression analysis, we found that the concomitant diazepam equivalent dose and presence of the CREB1 rs4675690 polymorphism were significantly associated with the antidepressant maintenance dose. We concluded that these factors influenced the antidepressant dose in maintenance therapy among Japanese patients with depression. However, further research is required in large cohorts.