Dabigatran (DAB) is an orally administered thrombin inhibitor. Both DAB and its main metabolite dabigatran acylglucuronide (DABG) have established anticoagulant effects. Here, we aimed to compare the relative anticoagulant effects of DABG and DAB in humans. Anticoagulant effects of DAB and DABG were measured in vitro using a thrombin generation assay. Additionally, their effects on other coagulation assays including PT, aPTT, TT, and fibrinogen were compared. Both DAB and DABG showed inhibitory effects on thrombin generation in a dose-dependent manner, but DABG exhibited a weaker inhibitory effect than that of DAB. The IC50 values of DAB and DABG on thrombin generation AUC were 134.1 ng/mL and 281.9 ng/mL, respectively. DABG also exhibited weaker anticoagulant effects than DAB on PT, aPTT, and TT. The results of the present study indicate that the anticoagulant effect of DABG, a main active DAB metabolite, is weaker than that of DAB.

This study aimed to evaluate whether the single nucleotide polymorphisms of ATP-binding cassette subfamily G member 2 (ABCG2) and solute carrier family 2 member 9 (SLC2A9) affect individual blood uric acid levels using pyrosequencing. ABCG2 (rs2231142, rs72552713, rs2231137), SLC2A9 (rs3734553, rs3733591, rs16890979), and individual uric acid levels were prospectively analyzed in 250 healthy young Korean male participants. Prominent differences in uric acid levels of the alleles were observed in the SLC2A9 rs3733591 polymorphism: wild-type (AA) vs. heterozygote (AG), 0.7 mg/dL (p < 0.0001); AA vs. mutant type (GG), 1.32 mg/dL (p < 0.0001); and AG vs. GG, 0.62 mg/dL (p < 0.01). In ABCG2 single nucleotide polymorphisms (SNPs), the statistically significant differences in uric acid levels were only found in rs2231142 between CC vs. AA (1.06 mg/dL; p < 0.001), and CC vs. CA (0.59 mg/dL; p < 0.01). Serum uric acid levels based on the ABCG2 and SLC2A9 diplotype groups were also compared. The uric acid levels were the lowest in the CC/AA diplotype and highest in the AA/AG diplotype. In addition, the SNP SLC2A9 rs3733591 tended to increase the uric acid levels when the ABCG2 rs2231142 haplotypes were fixed. In conclusion, both the ABCG2 rs2231142 and SLC2A9 rs3733591 polymorphisms may additively elevate blood uric acid levels.

Higher risk of major hemorrhage associated with concomitant use of dabigatran and simvastatin compared to other statins was previously reported with a suggestion of P-glycoprotein-mediated interaction. The aim of this study was to evaluate the effects of simvastatin on pharmacokinetics and anticoagulant effects of dabigatran, a direct oral anticoagulant. A total of 12 healthy subjects were enrolled in an open-label, two-period, single sequence study. Subjects were given 150 mg of dabigatran etexilate followed by 40 mg of once-daily simvastatin for seven days. Dabigatran etexilate was administered with simvastatin on the seventh day of simvastatin administration. Blood samples for pharmacokinetic and pharmacodynamic analyses were obtained until 24 h post-dose of dabigatran etexilate with or without co-administration of simvastatin. Pharmacokinetic parameters were derived from noncompartmental analysis for dabigatran etexilate, dabigatran, and dabigatran acylglucuronide. When simvastatin was co-administered, geometric mean ratios of area under time-concentration curves for dabigatran etexilate, dabigatran, and dabigatran acylglucuronide were 1.47, 1.21, and 1.57, respectively, compared to when dabigatran etexilate was administered alone. Thrombin generation assay and coagulation assay showed similar profiles between before and after co-administration of simvastatin. This study provides evidence that simvastatin treatment plays a minor role in modulating pharmacokinetics and anticoagulant effects of dabigatran etexilate.

There is a large variability in individual responses to atorvastatin administration. This study assessed the pharmacogenetic effects of solute carrier organic anion transporter family member 1B1 (SLCO1B1, c.388A>G and c.521T>C) and cytochrome P450 3A5 (CYP3A5, CYP3A5*3) genetic polymorphisms on the pharmacokinetics of atorvastatin and its active metabolite, 2-hydroxy (2-OH) atorvastatin, in 46 individuals who were administered a clinically used single oral dosage of 80 mg. The Cmax and AUC of atorvastatin in CYP3A5*3/*3 carriers were 2.6- and 2.8-fold higher, respectively, than those in CYP3A5*1/*1 carriers, and similar results were observed for 2-OH atorvastatin pharmacokinetics. SLCO1B1 c.521T>C also increased the AUC of atorvastatin and 2-OH atorvastatin. The AUC ratio of atorvastatin and 2-OH atorvastatin were not affected by SLCO1B1 c.388A>G or c.521T>C, whereas CYP3A5*3 reduced the AUC ratio. In an analysis evaluating the simultaneous effect of the SLCO1B1 c.521T>C and CYP3A5*3 polymorphisms, SLCO1B1 c.521TT/CYP3A5*1/*1 carriers showed lower Cmax and AUC values for atorvastatin and 2-OH atorvastatin than in individuals with the SLCO1B1 c.521T>C and/or CYP3A5*3 genotypes. Among the participants with the SLCO1B1 c.521TT genotype, the CYP3A5*3 carriers had a higher systemic exposure to atorvastatin and 2-OH atorvastatin than the CYP3A5*1/*1 carriers. Thus, SLCO1B1 c.521T>C and CYP3A5*3 polymorphisms affect the pharmacokinetics of atorvastatin and 2-OH atorvastatin.

Dapagliflozin, a selective sodium–glucose co-transporter-2 inhibitor, and linagliptin, a competitive, reversible dipeptidyl peptidase-4 inhibitor, are commonly prescribed antidiabetic medications in general clinics. Since there are several merits to combining them in a fixed-dose combination product, this study investigated the pharmacokinetic equivalence between the individual component (IC) and fixed-combination drug product (FCDP) forms of dapagliflozin and linagliptin. A randomized, open-label, single-dose crossover study was conducted. All participants (n = 48) were randomly allocated to group A (period 1: ICs, period 2: FCDP) or group B (period 1: FCDP, period 2: ICs), and each group received either a single dose of IN-C009 (FCDP) or single doses of both dapagliflozin and linagliptin. There was no statistically significant difference found between the pharmacokinetic variables of FCDP and IC. The values of estimated geometric mean ratios and the 90% confidence interval for both maximum concentration and area under the plasma drug concentration–time curve were within the range of 0.8–1.25 for both dapagliflozin and linagliptin. The results of the clinical study demonstrated comparable pharmacokinetic characteristics between IC and FCDP forms of dapagliflozin and linagliptin. The combined use of dapagliflozin and linagliptin was safe and tolerable in both formulations.