Physiologically based pharmacokinetic model analysis of the inhibitory effect of vonoprazan on the metabolic activation of proguanil.

We previously reported that repeated oral administration of vonoprazan (VPZ) followed by oral administration of proguanil (PG) in healthy adults increased blood concentration of PG and decreased blood concentration of its metabolite cycloguanil (CG) compared with administration of PG alone. In this study, we investigated whether this interaction can be quantitatively explained by VPZ inhibition of PG metabolism. In an in vitro study using human liver microsomes, VPZ inhibited CG formation from PG in a concentration-dependent manner, and the inhibition was enhanced depending on preincubation time. Then, a physiologically based pharmacokinetic (PBPK) model analysis was performed incorporating the obtained inhibition parameters. By fitting the blood concentration profiles of VPZ and PG/CG after VPZ and PG were orally administered alone to our PBPK model, parameters were obtained which can reproduce their concentration profiles. In contrast, when the VPZ inhibition parameters for CG formation from the in vitro study were incorporated, the predicted blood PG and CG concentrations were unchanged; the apparent dissociation constant had to be set to about 1/23 of the obtained in vitro value to reproduce the observed interaction. Further comprehensive evaluation is required, including the possibility that mechanisms other than metabolic inhibition may be involved.

[Assessment of Chemotherapy-Induced Adverse Events Using a Sharing System of Patient-Reported Information via a Touch Panel].

Screening for total pain and sharing of patient information including adverse events for patients receiving chemotherapy by medical staff is needed in clinical practice. We introduced a sharing system for patient-oriented outcome sheets via a touch panel at an outpatient chemotherapy clinic. This study aimed to assess whether the system contributes to the improved management of treatment-related adverse events. We retrospectively analyzed data from a total of 215 patients at Ehime University Hospital using their electronic medical records from April to August 2015. Forty of these patients had received interventions relating to treatment-related adverse events. The proportion of a total number of interventions before and after the sharing system was 42/282(14.9%)and 45/215(20.9%), respectively. The proportion of a total number of interventions at the first course of outpatient chemotherapy also increased from 9/40(22.5%)to 14/40(35%)compared with before the sharing system. The purpose of interventions were for insomnia, anorexia, and cancer-related pain, etc., listed in order of degree of frequency. These results suggest that a sharing system of patient-reported interview sheets contributes to tracking treatment -related adverse events and aids in ensuring interventions can be efficiently performed by multidisciplinary team members.

Preventive effect of pre-warming, hot compress, and pH adjustment in oxaliplatin-induced venous pain.

Background Venous pain induced by peripheral intravenous administration of oxaliplatin remains clinically unresolved. Objective The aim of this study was to determine the efficacy of comprehensive intervention care for venous pain in colorectal cancer patients receiving oxaliplatin. Setting A Japanese tertiary hospital. Method We treated all outpatients after April 2012 with comprehensive intervention care including pre-warming of the oxaliplatin solution, use of a hot compress, and pH adjustment by combination with dexamethasone. We retrospectively reviewed the electronic medical records from colorectal cancer patients who had received oxaliplatin via a peripheral vein between December 2009 and June 2014. Main outcome measures The primary endpoint of this study was the incidence of venous pain at the administration site during oxaliplatin infusion, according to injection site reaction grade ≥ 2. Results We evaluated 271 treatment courses in 59 patients. Venous pain occurred in 42 courses (15.5%) among 26 patients. Multivariate logistic regression analysis revealed that female gender and body mass index ≥ 25 kg/m2 were significantly associated with an increased risk of venous pain during all courses (adjusted odds ratio [OR]: 3.18, 95% confidence interval [CI] 1.35-7.92; P < 0.01; and adjusted OR: 3.37, 95% CI 1.26-9.40; P = 0.02, respectively), whereas comprehensive intervention care were significantly associated with reduced risk of venous pain during all courses (adjusted OR: 0.10, 95% CI 0.02-0.44; P < 0.01). Conclusion Comprehensive intervention care is a clinical treatment option for oxaliplatin-induced peripheral venous pain in patients with colorectal cancer, especially females with obesity.

High Ferritin Level and Malnutrition Predict High Risk of Infection-Related Hospitalization in Incident Dialysis Patients: A Japanese Prospective Cohort Study.

AIMS: The aim of the study was to clarify the relationship between serum ferritin and infectious risks. METHODS: We evaluated all hospital admissions due to infections, clinical biomarkers and nutrition status in 129 incident Japanese dialysis patients during a median follow-up of 38 months. RESULTS: Kaplan-Meier analysis revealed that the period without infections requiring hospitalization was significantly shorter in ferritin > median (82.0 ng/ml) group than in the ferritin < median group (log-rank test 4.44, p = 0.035). High ferritin was associated with significantly increased relative risk of hospitalization for infection (Cox hazard model 1.52, 95% CI 1.06-2.17). The number of hospitalization days was gradually longer in patients with high ferritin levels and malnutrition. CONCLUSION: Although serum ferritin levels were low, and doses of iron administered to dialysis patients in Japan are generally lower than in Western countries, an elevated ferritin level was associated with increased risk of infection, particularly in patients with poor nutritional status.

[Risk Factors for Oxaliplatin-Induced Phlebitis and Venous Pain, and Evaluation of the Preventive Effect of Preheating with a Hot Compress for Administration of Oxaliplatin].

Venous pain induced by oxaliplatin(L-OHP)is a clinical issue related to adherence to the Cape OX regimen. To prevent LOHP- induced venous pain, we provided nursing care to outpatients who were administered a preheated L -OHP diluted solution using a hot compress. We retrospectively evaluated the risk factors for colorectal cancer patients who had L -OHP induced phlebitis and venous pain. Furthermore, the preventive effect of nursing care was compared between inpatients and outpatients from January 2010 to March 2012. At the L-OHP administration site, any symptoms were defined as phlebitis, whereas pain was defined as venous pain. A total of 132 treatment courses among 31 patients were evaluated. Multivariate logistic regression analysis revealed that both phlebitis and venous pain were significantly more common in female patients (adjusted odds ratio, 2.357; 95%CI: 1.053-5.418; and adjusted odds ratio, 5.754; 95%CI: 2.119-18.567, respectively). The prevalence of phlebitis and venous pain did not differ between inpatients and outpatients (phlebitis, 61.3% vs 67.7%; venous pain, 29.0%vs 19.4%). These results suggest that administration of L-OHP via a central venous route should be considered in female patients.