Xiaoni Liu

Characterization of Renal Glucose Reabsorption in Response to Dapagliflozin in Healthy Subjects and Subjects With Type 2 Diabetes

OBJECTIVE To examine the effect of dapagliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor, on the major components of renal glucose reabsorption (decreased maximum renal glucose reabsorptive capacity [TmG], increased splay, and reduced threshold), using the pancreatic/stepped hyperglycemic clamp (SHC) technique. RESEARCH DESIGN AND METHODS Subjects with type 2 diabetes (n = 12) and matched healthy subjects (n = 12) underwent pancreatic/SHC (plasma glucose range 5.5–30.5 mmol/L) at baseline and after 7 days of dapagliflozin treatment. A pharmacodynamic model was developed to describe the major components of renal glucose reabsorption for both groups and then used to estimate these parameters from individual glucose titration curves. RESULTS At baseline, type 2 diabetic subjects had elevated TmG, splay, and threshold compared with controls. Dapagliflozin treatment reduced the TmG and splay in both groups. However, the most significant effect of dapagliflozin was a reduction of the renal threshold for glucose excretion in type 2 diabetic and control subjects. CONCLUSIONS The SGLT2 inhibitor dapagliflozin improves glycemic control in diabetic patients by reducing the TmG and threshold at which glucose is excreted in the urine.

Lack of pharmacokinetic interaction between dapagliflozin, a novel sodium–glucose transporter 2 inhibitor, and metformin, pioglitazone, glimepiride or sitagliptin in healthy subjects

Aims: Dapagliflozin increases urinary glucose excretion by selectively inhibiting renal sodium–glucose transporter 2, an insulin‐independent mechanism of action that may be complementary to that of other oral antidiabetes drugs. The current studies assessed the potential for pharmacokinetic (PK) interaction between dapagliflozin and pioglitazone, metformin, glimepiride or sitagliptin in healthy subjects following single‐dose administration.

Pharmacokinetics and pharmacodynamics of dapagliflozin, a novel selective inhibitor of sodium–glucose co-transporter type 2, in Japanese subjects without and with type 2 diabetes mellitus

Aims: Dapagliflozin, a selective, orally active inhibitor of the renal sodium–glucose co‐transporter type 2 (SGLT2) is in development for the treatment of type 2 diabetes mellitus (T2DM). Here, the pharmacokinetics (PK) and pharmacodynamics (PD) of dapagliflozin were evaluated in healthy Japanese subjects and in Japanese subjects with T2DM.

The influence of kidney function on dapagliflozin exposure, metabolism and pharmacodynamics in healthy subjects and in patients with type 2 diabetes mellitus

AIM(S) This study assessed the effect of differences in renal function on the pharmacokinetics and pharmacodynamics of dapagliflozin, a renal sodium glucose co-transporter-2 (SGLT2) inhibitor for the treatment of type 2 diabetes mellitus (T2DM). METHODS A single 50 mg dose of dapagliflozin was used to assess pharmacokinetics and pharmacodynamics in five groups: healthy non-diabetic subjects; patients with T2DM and normal kidney function and patients with T2DM and mild, moderate or severe renal impairment based on estimated creatinine clearance. Subsequently, 20 mg once daily multiple doses of dapagliflozin were evaluated in the patients with T2DM. Formation rates of dapagliflozin 3-O-glucuronide (D3OG), an inactive metabolite, were evaluated using human isolated kidney and liver microsomes. RESULTS Plasma concentrations of dapagliflozin and D3OG were incrementally increased with declining kidney function. Steady-state Cmax for dapagliflozin were 4%, 6% and 9% higher and for D3OG were 20%, 37% and 52% higher in patients with mild, moderate and severe renal impairment, respectively, compared with normal function. AUC(0,τ) was likewise higher. D3OG formation in kidney microsomes was three-fold higher than in liver microsomes and 109-fold higher than in intestine microsomes. Compared with patients with normal renal function, pharmacodynamic effects were attenuated with renal impairment. Steady-state renal glucose clearance was reduced by 42%, 83% and 84% in patients with mild, moderate or severe renal impairment, respectively. CONCLUSIONS These results indicate that both kidney and liver significantly contribute to dapagliflozin metabolism, resulting in higher systemic exposure with declining kidney function. Dapagliflozin pharmacodynamics in diabetic subjects with moderate to severe renal impairment are consistent with the observation of reduced efficacy in this patient population.

Lack of Pharmacokinetic Interactions Between Dapagliflozin and Simvastatin, Valsartan, Warfarin, or Digoxin

IntroductionCoronary heart disease, stroke, and peripheral vascular disease are the most common causes of mortality in patients with type 2 diabetes mellitus (T2DM). The aim of these studies was to assess the potential for pharmacokinetic interaction between dapagliflozin, a sodium glucose co-transporter-2 inhibitor being developed for the treatment of T2DM, and four medications commonly prescribed in patients with T2DM and cardiovascular disease: simvastatin, valsartan, warfarin, and digoxin.MethodsPotential pharmacokinetic interactions between 20 mg dapagliflozin, 40 mg simvastatin, or 320 mg valsartan were assessed in an openlabel, randomized, five-period, five-treatment, unbalanced crossover study in 24 healthy subjects. In a second study, the effects of steadystate dapagliflozin on the pharmacokinetics of 25 mg warfarin or 0.25 mg digoxin were assessed in an open-label, randomized, two-period, two-treatment crossover study in 30 healthy subjects divided into two cohorts. The potential pharmacodynamic interaction between dapagliflozin and warfarin was also evaluated.ResultsAll treatments were well tolerated. Neither simvastatin nor valsartan had any clinically meaningful effect on the pharmacokinetics of dapagliflozin. Dapagliflozin increased the area under the curve for simvastatin, simvastatin acid, and valsartan by approximately 19%, 30%, and 6%, respectively, and decreased the maximum observed plasma concentration of valsartan by approximately 6%. These effects were not considered clinically meaningful. In addition, dapagliflozin had no effect on the pharmacokinetics of either digoxin or warfarin. The pharmacodynamics of warfarin were also unaffected by dapagliflozin.ConclusionIn these studies the co-administration of dapagliflozin and simvastatin, valsartan, warfarin, or digoxin was well tolerated without clinically meaningful drug-drug interaction.

Influence of hepatic impairment on the pharmacokinetics and safety profile of dapagliflozin: an open-label, parallel-group, single-dose study.

BACKGROUND Dapagliflozin, a selective inhibitor of renal sodium glucose co-transporter 2, is under development for the treatment of type 2 diabetes mellitus. Dapagliflozin elimination is primarily via glucuronidation to an inactive metabolite, dapagliflozin 3-O-glucuronide. Pharmacokinetic studies are recommended in subjects with impaired hepatic function if hepatic metabolism accounts for a substantial portion of the absorbed drug. OBJECTIVE The purpose of our study was to compare the pharmacokinetics of dapagliflozin in patients with mild, moderate, or severe hepatic impairment (HI) with healthy subjects. METHODS This was an open-label, parallel-group study in male or female patients with mild, moderate, or severe HI (6 per group according to Child-Pugh classification) and in 6 healthy control subjects. The control subjects were matched to the combined HI group for age (±10 years), weight (±20%), sex, and smoking status, with no deviations from normal in medical history, physical examination, ECG, or laboratory determinations. All participants received a single 10-mg oral dose of dapagliflozin, and the pharmacokinetics of dapagliflozin and dapagliflozin 3-O-glucuronide were characterized. Dapagliflozin tolerability was also assessed throughout the study. RESULTS Demographic characteristics and baseline physical measurements (weight, height, and body mass index) were similar among the 18 patients in the HI groups (58-126 kg; 151.2-190.0 cm, and 31.5-37.7 kg/m(2), respectively) and the healthy subject group (65.0-102.6 kg; 166.0-184.0 cm, and 23.3-34.3 kg/m(2), respectively). In those with mild, moderate, or severe HI, dapagliflozin mean C(max) values were 12% lower and 12% and 40% higher than healthy subjects, respectively. Mean dapagliflozin AUC(0-∞) values were 3%, 36%, and 67% higher compared with healthy subjects, respectively. Dapagliflozin 3-O-glucuronide mean C(max) values were 4% and 58% higher and 14% lower in those with mild, moderate, or severe HI compared with healthy subjects, respectively, and mean dapagliflozin 3-O-glucuronide AUC(0-∞) values were 6%, 100%, and 30% higher compared with healthy subjects, respectively. These values were highly dependent on the calculated creatinine clearance of each group. All adverse events were mild or moderate, with no imbalance in frequency between groups. CONCLUSIONS Compared with healthy subjects, systemic exposure to dapagliflozin in subjects with HI was correlated with the degree of HI. Single 10-mg doses of dapagliflozin were generally well tolerated by participants in this study. Due to the higher dapagliflozin exposures in patients with severe HI, the benefit:risk ratio should be individually assessed because the long-term safety profile and efficacy of dapagliflozin have not been specifically studied in this population.

Effects of rifampin and mefenamic acid on the pharmacokinetics and pharmacodynamics of dapagliflozin

Dapagliflozin is a selective sodium glucose cotransporter 2 (SGLT2) inhibitor that decreases serum glucose by reducing renal glucose reabsorption, thereby promoting urinary glucose excretion. Dapagliflozin is primarily metabolized via the uridine diphosphate‐glucuronosyltransferase (UGT)1A9 pathway to its major inactive metabolite, dapagliflozin 3‐O‐glucuronide. The aim of this study was to evaluate the potential for drug‐drug interaction between dapagliflozin and two potential UGT1A9 modulators.

Effect of a high-fat meal on the pharmacokinetics of dapagliflozin, a selective SGLT2 inhibitor, in healthy subjects

Dapagliflozin is a potent and selective inhibitor of sodium–glucose co‐transporter type 2 that is being developed for the treatment of type 2 diabetes mellitus. This open‐label, randomized, two‐period, two‐treatment (single doses of 10‐mg dapagliflozin fasted or fed), crossover study was conducted to evaluate the effect of a high‐fat meal on the pharmacokinetics of dapagliflozin in 14 healthy subjects. Compared to the fasted state, a high‐fat meal decreased mean dapagliflozin maximum plasma concentrations (Cmax) by 31%, increased the time to Cmax (Tmax) by 1 h, but did not affect overall dapagliflozin systemic exposure [area under the plasma concentration‐time curve (AUC)]. As the cumulative (daily) amount of glucose excreted in the urine induced by dapagliflozin is dependent upon dapagliflozin AUC, the effect of food on dapagliflozin Cmax is unlikely to have a clinically meaningful effect on dapagliflozins efficacy. On the basis of these findings, dapagliflozin can be administered without regard to meals.

Pharmacokinetic and Pharmacodynamic Properties of Single- and Multiple-Dose of Dapagliflozin, a Selective Inhibitor of SGLT2, in Healthy Chinese Subjects

BACKGROUND Dapagliflozin, a selective, orally active, renal sodium glucose cotransporter 2 (SGLT2) 2 inhibitor, is under investigation as a treatment of type 2 diabetes mellitus (T2DM). Dapagliflozin reduces hyperglycemia by inhibiting renal glucose reabsorption and dose-dependently increasing urinary glucose excretion, independent of insulin secretion or action. OBJECTIVES These studies assessed the single- and multiple-dose pharmacokinetic and pharmaco dynamic properties of dapagliflozin and its major inactive metabolite, dapagliflozin 3-O-glucuronide (D3OG), in healthy subjects residing in China. METHODS In 2 identically designed, open-label, single- and multiple-dose studies (n = 14 for both studies), healthy Chinese subjects were administered oral dapagliflozin 5 or 10 mg. In both studies, subjects received a single dose on day 1 (single-dose administration period) followed by 6 once-daily doses on days 5 to 10 (multiple-dose administration period). Pharmacokinetic parameters (plasma and urinary dapagliflozin and D3OG), pharmacodynamic response (urinary glucose excretion), and tolerability were assessed. RESULTS Fourteen subjects completed the dapagliflozin 5-mg study, and 13 completed the dapagliflozin 10-mg study. Baseline characteristics were balanced across the two studies: 9 versus 10 men; mean age, 27.1 versus 28.9 years; mean weight, 62.8 versus 62.2 kg; and mean body mass index, 23.0 versus 22.2 kg/m(2) in the dapagliflozin 5- and 10-mg studies, respectively. In both doses, dapagliflozin was rapidly absorbed (T(max), ≤1.5 h), accumulation (defined as the geometric mean ratio of AUC(τ) at day 10 to AUC(τ) at day 1) after multiple dosing was minimal (<1.13 fold), and elimination half-life was 10 to 12 h. D3OG showed a slightly longer median Tmax (≤2 h) but a similar plasma concentration-time profile and half-life compared with dapagliflozin. The majority of D3OG (up to 69.7% of the dapagliflozin dose) was excreted in urine, while ≤1.9% of dapagliflozin was excreted unchanged in urine. Over a 24-hour period and at steady state (day 10), urinary glucose excretion values were 28.1 and 41.1 g with dapagliflozin 5 and 10 mg, respectively. Dapagliflozin was generally well tolerated; one dapagliflozin 10 mg-treated subject discontinued the study because of a serious adverse event (bronchitis) considered by the investigator as unrelated to dapagliflozin dosing. CONCLUSIONS Pharmacokinetic and pharmacodynamic characteristics following single- and multiple-dose dapagliflozin 5 and 10 mg oral administration in healthy Chinese subjects were as predicted from previous studies and were similar to findings observed in non-Chinese healthy subjects. Dapagliflozin dosing was well tolerated. The clinically recommended dapagliflozin dose of 10 mg once daily is expected to be appropriate in patients of Chinese ethnicity; results from an efficacy and tolerability study in Chinese patients with T2DM are awaited.

Bioequivalence, Food Effect, and Steady-State Assessment of Dapagliflozin/Metformin Extended-release Fixed-dose Combination Tablets Relative to Single-component Dapagliflozin and Metformin Extended-release Tablets in Healthy Subjects.

PURPOSE Simplification of therapeutic regimens for patients with type 2 diabetes mellitus can provide convenience that leads to improved compliance. Dapagliflozin/metformin extended-release (XR) fixed-dose combination (FDC) tablets offer the convenience of once-daily dosing. Two pharmacokinetic (PK) studies were conducted to establish bioequivalence for 2 doses of dapagliflozin/metformin XR FDC versus the same dosage of the individual component (IC) tablets in healthy adults. METHODS Two open-label, randomized, 4-period, 4-arm crossover studies were conducted to assess the bioequivalence and PK properties of dapagliflozin and metformin FDCs in healthy subjects under fed and fasting conditions. Participants received single oral doses or once-daily dosing of dapagliflozin/metformin XR (5 mg/500 mg [study 1] or 10 mg/1000 mg [study 2]) for 4 days in an FDC formulation or corresponding strengths of IC tablets. FINDINGS For both of the studies, dapagliflozin and metformin 5 mg/500 mg or 10 mg/1000 mg FDC tablets were bioequivalent to the respective IC tablets. The 90% CIs of the ratio of the adjusted geometric means for all key PK parameters (Cmax, AUC0-T, and AUC0-∞) were contained within the predefined 0.80 to 1.25 range to conclude bioequivalence for both dapagliflozin and metformin. Once-daily dosing to steady state of each FDC tablet had no effect on the PK properties of dapagliflozin or metformin. When the FDCs were administered with a light-fat meal, there was no effect on metformin PK values and only a modest, nonclinically meaningful effect on dapagliflozin PK values. There were no safety or tolerability concerns. IMPLICATIONS Bioequivalence of the FDCs of dapagliflozin/metformin XR and the ICs was established, and no safety issues of clinical concern were raised.