Effects of UGT1A1 Polymorphism, Gender and Triglyceride on the Pharmacokinetics of Telmisartan in Chinese Patients with Hypertension: A Population Pharmacokinetic Analysis

Genetic evaluation in indeterminate acute liver failure: A post hoc analysis

BACKGROUND AND STUDY AIMS

There are limited data regarding indeterminate acute liver failure (ALF). The study aims to perform a post hoc analysis using genetic methods for the ALF cases with indeterminate etiology.

PATIENTS AND METHODS

Stored blood samples from these patients with indeterminate ALF were collected. Whole-exome sequencing (WES) was used to evaluate the pathogenesis of indeterminate ALF.

RESULTS

A total of 16 samples from 11 adult patients and 5 pediatric patients with indeterminate ALF were available. Among the adult patients, one female patient was identified with two heterozygous variants (c.2333G > T (p.Arg778Leu) and c.2310C > G (p.Leu770 = )) in the adenosine triphosphatase copper-transporting beta (ATP7B) gene, and two male patients were found to harbor heterozygous and homozygous variants (c.686C > A (p.Pro229Gln) plus homozygousvariantA(TA)6TAAinsTA (-), andc.1456 T > G (p.Tyr486Asp) plus c.211G > A (p.Gly71Arg)) in the uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) gene. For the pediatric patients, single heterozygous variant (c.2890C > T (p.Arg964Cys)) in the polymerase gamma (POLG) gene was found in 1 male child, and two heterozygous variants (c.1909A > G (p.Lys637Glu) and c.3646G > A (p.Val1216Ile)) in the tetratricopeptide repeat domain 37 (TTC37) gene were found in 1 female child. No variants clinically associated with known liver diseases were revealed in the remaining patients.

CONCLUSION

These results expand the knowledge of ALF with indeterminate etiology. WES is helpful to reveal possible candidate genes for indeterminate ALF, but incomplete consistency between the genotype and phenotype in some cases still challenge the accurate diagnosis.

Transporter and metabolizer gene polymorphisms affect fluoroquinolone pharmacokinetic parameters

Tuberculosis (TB) is an infectious disease that occurs globally. Treatment of TB has been hindered by problems with multidrug-resistant strains (MDR-TB). Fluoroquinolones are one of the main drugs used for the treatment of MDR-TB. The success of therapy can be influenced by genetic factors and their impact on pharmacokinetic parameters. This review was conducted by searching the PubMed database with keywords polymorphism and fluoroquinolones. The presence of gene polymorphisms, including UGT1A1, UGT1A9, SLCO1B1, and ABCB1, can affect fluoroquinolones pharmacokinetic parameters such as area under the curve (AUC), creatinine clearance (C_Cr), maximum plasma concentration (C_max), half-life (t_1/2) and peak time (t_max) of fluoroquinolones.

Polymorphisms contribute to differences in the effect of rocuronium in Chinese patients

Rocuronium is widely utilized in clinical general anaesthesia, and individual differences in pharmacology and clearance have been observed. Two hundred thirty-six Chinese patients undergoing selective thyroid/breast mass resection were studied. Total intravenous anaesthesia was induced with a single dose of propofol (2 mg·kg^-1 ), sufentanil (0.5 μg·kg^-1 ), and rocuronium (0.6 mg·kg^-1 ) and maintained with propofol (3-5 mg·kg^-1 ·h^-1 ) and remifentanil (0.2-0.4 μg·kg^-1 ·min^-1 ). Intubation conditions and a train-of-four index of patients were utilized to assess the effects and duration of rocuronium. The data from 228 patients were analysed and reported. Genotypes NR1I2 rs2472677 C > T, NR1I2 rs6785049 G > A, SLCO1B1 rs4363657 T > C, SLCO1A2 rs4762699 T > C, and UGT1A1 rs4148323 G > A contributed to individual variation in rocuronium. Of the clinical variables tested, age, BMI, total dose of propofol, NR1I2 rs2472677, and SLCO1A2 rs4762699 correlated significantly (P < 0.05 for all) with the clinical duration or total clinical action time of rocuronium in a multiple linear regression model. No significant interactions were observed in intubation conditions. Genetic variations in NR1I2 rs2472677, NR1I2 rs6785049, SLCO1B1 rs4363657, SLCO1A2 rs4762699, and UGT1A1 rs4148323 were related to extensive interindividual variability in the clinical duration and total clinical action time of rocuronium.

Population Pharmacokinetics Modelling and Simulation of Mitotane in Patients with Adrenocortical Carcinoma: An Individualized Dose Regimen to Target All Patients at Three Months?

Mitotane is the most effective agent in post-operative treatment of adrenocortical carcinoma. In adults, the starting dose is 2–3 g/day and should be slightly increased to reach the therapeutic index of 14–20 mg/L. This study developed a population PK model for mitotane and to simulate recommended/high dosing regimens. We retrospectively analyzed the data files of 38 patients with 503 plasma concentrations for the pharmacokinetic analysis. Monolix version 2019R1 was used for non-linear mixed-effects modelling. Monte Carlo simulations were performed to evaluate the probability of target attainment (PTA ≥ 14 mg/L) at one month and at three months. Mitotane concentration data were best described by a linear one-compartment model. The estimated PK parameters (between-subject variability) were: 8900 L (90.4%) for central volume of distribution (V) and 70 L·h⁻¹ (29.3%) for clearance (Cl). HDL, Triglyceride (Tg) and a latent covariate were found to influence Cl. The PTA at three months for 3, 6, 9, and 12 g per day was 10%, 55%, 76%, and 85%, respectively. For a loading dose of 15 g/day for one month then 5 g/day, the PTA in the first and third months was 57 and 69%, respectively. This is the first PKpop model of mitotane highlighting the effect of HDL and Tg covariates on the clearance as well as a subpopulation of ultrafast metabolizer. The simulations suggest that recommended dose regimens are not enough to target the therapeutic threshold in the third month.