Impact of CYP3A5 genotype on tolvaptan pharmacokinetics and their relationships with endogenous markers of CYP3A activity and serum sodium level in heart failure patients

Characterization of plasma vonoprazan and CYP3A activity using its endogenous marker and genetic variants in patients with digestive system disorders

Factors that determine clinical responses to vonoprazan remain unknown. This study aimed to characterize plasma vonoprazan and CYP3A activity using its endogenous marker and genetic variants in patients with digestive system disorders. Fifty-three patients who were receiving vonoprazan for at least 3 days were enrolled. Blood samples for determination of plasma vonoprazan and its metabolite (ODA-VP) were obtained. Plasma 4β-hydroxycholesterol (4β-OHC), CYP3A5 and ABCB1 genotypes, and plasma gastrin were determined. CYP3A recognition for vonoprazan was evaluated using recombinant CYP3A proteins. Plasma vonoprazan levels exhibited a large interindividual variation. The absolute plasma concentration of vonoprazan was correlated with its dose-normalized value, and had a positive correlation with the inverse value of its metabolic ratio. A negative correlation was observed between plasma vonoprazan and 4β-OHC levels. The metabolic ratio of vonoprazan was positively correlated with the plasma 4β-OHC level. Genetic variants of CYP3A5 and ABCB1 were not associated with the plasma concentration of vonoprazan and its metabolic ratio. Possible saturated metabolism of vonoprazan to its major metabolite was observed at a therapeutic dose. Although the CYP3A5 genotype did not alter plasma vonoprazan, CYP3A activity based on plasma 4β-OHC partially explained the variation in plasma vonoprazan in patients with digestive system disorders.

Effect of vitamin D supplements on left ventricular ejection fraction in patients with heart failure: A systematic review and meta-analysis of randomized controlled trials

Cardiovascular diseases (CVD) are the most common cause of death worldwide. Among CVDs, heart failure (HF) is known to be the most common cause of hospitalization in patients over 65. Despite all proposed treatments for CVDs, mortality and morbidity still remain high. There are controversial reports available on vitamin D efficacy in patients with HF. In this systematic review and meta-analysis, we aimed to investigate whether vitamin D is effective at enhancing ejection fraction (EF) in patients with HF. We performed a systematic search across different databases (PubMed, SCOPUS, Web of Science, EMBASE, SciELO and Google Scholar) up to 1 Jan 2020 without any language or location limitations. Our suggested Population/Intervention/Comparison/Outcome/Type of study (PICOT) was P: patients with HF, I: vitamin D, C: placebo or no treatment, O: EF and T: clinical trials. To achieve the highest sensitivity, only keywords associate with P and I were selected for the search query. A total number of 5397 primary studies were found, of which 13 were elected for data synthesis. Clinical trials were published and available since 2005 up to 2019 and a total number of 1215 patients were included. Our results showed that vitamin D can significantly enhance left ventricular EF in HF patients by 3.304% (95% confidence interval [CI] 0.954, 5.654, p=0.006). Based on our observations, we conclude that before conducting a large number of high quality clinical trials and further meta-analysis, vitamin D should be prescribed to all patients with HF.

Effect of vitamin D supplements on left ventricular ejection fraction in patients with heart failure: A systematic review and meta-analysis of randomized controlled trials

Cardiovascular diseases (CVD) are the most common cause of death worldwide. Among CVDs, heart failure (HF) is known to be the most common cause of hospitalization in patients over 65. Despite all proposed treatments for CVDs, mortality and morbidity still remain high. There are controversial reports available on vitamin D efficacy in patients with HF. In this systematic review and meta-analysis, we aimed to investigate whether vitamin D is effective at enhancing ejection fraction (EF) in patients with HF. We performed a systematic search across different databases (PubMed, SCOPUS, Web of Science, EMBASE, SciELO and Google Scholar) up to 1 Jan 2020 without any language or location limitations. Our suggested Population/Intervention/Comparison/Outcome/Type of study (PICOT) was P: patients with HF, I: vitamin D, C: placebo or no treatment, O: EF and T: clinical trials. To achieve the highest sensitivity, only keywords associate with P and I were selected for the search query. A total number of 5397 primary studies were found, of which 13 were elected for data synthesis. Clinical trials were published and available since 2005 up to 2019 and a total number of 1215 patients were included. Our results showed that vitamin D can significantly enhance left ventricular EF in HF patients by 3.304% (95% confidence interval [CI] 0.954, 5.654, p=0.006). Based on our observations, we conclude that before conducting a large number of high quality clinical trials and further meta-analysis, vitamin D should be prescribed to all patients with HF.

Sources of Interindividual Variability

The efficacy, safety, and tolerability of drugs are dependent on numerous factors that influence their disposition. A dose that is efficacious and safe for one individual may result in sub-therapeutic or toxic blood concentrations in others. A significant source of this variability in drug response is drug metabolism, where differences in presystemic and systemic biotransformation efficiency result in variable degrees of systemic exposure (e.g., AUC, C_max, and/or C_min) following administration of a fixed dose.Interindividual differences in drug biotransformation have been studied extensively. It is recognized that both intrinsic factors (e.g., genetics, age, sex, and disease states) and extrinsic factors (e.g., diet , chemical exposures from the environment, and the microbiome) play a significant role. For drug-metabolizing enzymes, genetic variation can result in the complete absence or enhanced expression of a functional enzyme. In addition, upregulation and downregulation of gene expression, in response to an altered cellular environment, can achieve the same range of metabolic function (phenotype), but often in a less predictable and time-dependent manner. Understanding the mechanistic basis for variability in drug disposition and response is essential if we are to move beyond the era of empirical, trial-and-error dose selection and into an age of personalized medicine that will improve outcomes in maintaining health and treating disease.