Dapagliflozin pharmacokinetics is similar between patients with heart failure with reduced ejection fraction and patients with type 2 diabetes mellitus.

Dapagliflozin was recently approved for use in adults with chronic heart failure with reduced ejection fraction (HFrEF) with/without type 2 diabetes mellitus (T2DM). The objectives of this analysis were to characterize dapagliflozin pharmacokinetics in patients with HFrEF and to compare dapagliflozin systemic exposure between adults with HFrEF with/without T2DM and adults with T2DM. A nonlinear mixed-effects modelling approach was applied; the population-pharmacokinetic model was developed using 9735 dapagliflozin plasma concentrations from 2744 patients. The final two-compartmental model adequately described the observed dapagliflozin concentrations, with a similar estimated apparent clearance compared with a previous estimate in patients with T2DM without HF and in healthy subjects (23.0 [95% CI: 22.6-23.9] L/h vs. 22.9 [95% CI: 22.1-23.7] L/h). The model-predicted median area under the dapagliflozin concentration-time profile was ≤1.2-fold higher in patients with HFrEF vs. those with T2DM without HFrEF, which is not considered clinically relevant. Dapagliflozin exposure was similar between patients with HFrEF with/without T2DM and T2DM patients without HFrEF.

Application of population physiologically based pharmacokinetic modelling to optimize target expression and clearance mechanisms of therapeutic monoclonal antibodies.

AIMS: To use population physiologically based pharmacokinetic (PopPBPK) modelling to optimize target expression, kinetics and clearance of HER1/2 directed therapeutic monoclonal antibodies (mAbs). Thus, to propose a general workflow of PopPBPK modelling and its application in clinical pharmacology. METHODS: Full PBPK model of pertuzumab (PTZ) was developed in patient population using Simcyp V21R1 incorporating mechanistic targeted-mediated drug disposition process by fitting known clinical PK and sparse receptor proteomics data to optimize target expression and kinetics of HER2 receptor. Trastuzumab (TTZ) PBPK modelling was used to validate the optimized HER2 target. Additionally, the simulator was also used to develop a full PBPK model for the HER1-directed mAb cetuximab (CTX) to assess the underlying targeted-mediated drug disposition-independent elimination mechanisms. RESULTS: HER2 final parameterisation coming from the PBPK modelling of PTZ was successfully cross validated through PBPK modelling of TTZ with average fold error (AFE), absolute AFE and percent prediction error values for area under the concentration-time curve (AUC) and maximum plasma concentration (Cmax ) of 1.13, 1.16 and 16, and 1.01, 1.07 and 7, respectively. CTX PBPK model performance was validated after the incorporation of an additional systemic clearance of 0.033 L/h as AFE and absolute AFE showed an acceptable predictive power of AUC and Cmax with percent prediction error of 13% for AUC and 10% for Cmax . CONCLUSIONS: Optimisation of both system and drug related parameters were performed through PBPK modelling to improve model performance of therapeutic mAbs (PTZ, TTZ and CTX). General workflow was proposed to develop and apply PopPBPK to support clinical development of mAbs targeting same receptor.

Common UGT1A9 polymorphisms do not have a clinically meaningful impact on the apparent oral clearance of dapagliflozin in type 2 diabetes mellitus.

Dapagliflozin is an inhibitor of human renal sodium-glucose cotransporter 2 (SGLT2), first approved for the treatment of type 2 diabetes mellitus (T2DM). Dapagliflozin is primarily metabolized by uridine diphosphate glucuronosyltransferase 1A9 (UGT1A9). The effect of UGT1A9 polymorphisms on dapagliflozin apparent oral clearance (CL/F) was studied with dapagliflozin population pharmacokinetic data and UGT1A9 genotype data (I.399C>T, rs2011404, rs6759892, rs7577677, rs4148323, UGT1A9*2 and UGT1A9*3) from a Phase 2 study conducted in subjects with T2DM (n = 187). An analysis of covariance (ANCOVA) model accounting for known covariates influencing dapagliflozin CL/F was applied to these data to quantify the impact of each UGT1A9 polymorphism relative to the wildtype UGT1A9 genotype. The analysis showed that the geometric mean ratios of dapagliflozin CL/F for all of the UGT1A9 polymorphisms studied were within the range of wildtype UGT1A9 CL/F values. Consequently, the polymorphisms of UGT1A9 studied had no clinically meaningful impact on the CL/F of dapagliflozin.

Dapagliflozin and Diuretic Use in Patients With Heart Failure and Reduced Ejection Fraction in DAPA-HF.

BACKGROUND: In the DAPA-HF trial (Dapagliflozin and Prevention of Adverse-Outcomes in Heart Failure), the sodium-glucose cotransporter 2 inhibitor dapagliflozin reduced the risk of worsening heart failure and death in patients with heart failure and reduced ejection fraction. We examined the efficacy and tolerability of dapagliflozin in relation to background diuretic treatment and change in diuretic therapy after randomization to dapagliflozin or placebo. METHODS: We examined the effects of study treatment in the following subgroups: no diuretic and diuretic dose equivalent to furosemide <40, 40, and >40 mg daily at baseline. We examined the primary composite end point of cardiovascular death or a worsening heart failure event and its components, all-cause death and symptoms. RESULTS: Of 4616 analyzable patients, 736 (15.9%) were on no diuretic, 1311 (28.4%) were on <40 mg, 1365 (29.6%) were on 40 mg, and 1204 (26.1%) were taking >40 mg. Compared with placebo, dapagliflozin reduced the risk of the primary end point across each of these subgroups: hazard ratios were 0.57 (95% CI, 0.36-0.92), 0.83 (95% CI, 0.63-1.10), 0.77 (95% CI, 0.60-0.99), and 0.78 (95% CI, 0.63-0.97), respectively (P for interaction=0.61). The hazard ratio in patients taking any diuretic was 0.78 (95% CI, 0.68-0.90). Improvements in symptoms and treatment toleration were consistent across the diuretic subgroups. Diuretic dose did not change in most patients during follow-up, and mean diuretic dose did not differ between the dapagliflozin and placebo groups after randomization. CONCLUSIONS: The efficacy and safety of dapagliflozin were consistent across the diuretic subgroups examined in DAPA-HF. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03036124.

Cardiovascular and renal safety of metformin in patients with diabetes and moderate or severe chronic kidney disease: Observations from the EXSCEL and SAVOR-TIMI 53 cardiovascular outcomes trials.

AIM: To provide evidence on the cardiovascular and renal safety of metformin in chronic kidney disease (CKD) stages 3 to 4. MATERIALS AND METHODS: This post hoc analysis compared participants with an estimated glomerular filtration rate (eGFR) of 15 to 59 mL/min/1.73m2 in the Exenatide Study of Cardiovascular Event Lowering (EXSCEL) and the Saxagliptin and Cardiovascular Outcomes in Patients With Type 2 Diabetes Mellitus (SAVOR-TIMI 53) trials taking metformin, with those not exposed to metformin during these trials, using a propensity-matching approach. Adjusted Cox proportional hazards models were used to assess risk of major adverse cardiovascular events (MACE) and all-cause mortality (ACM). Metformin effect on eGFR slope was calculated using a mixed-model repeated measures analysis, and the number of lactic acidosis events was tabulated. RESULTS: No strong trend for lower metformin doses with lower eGFR values was observed in either the EXSCEL or SAVOR-TIMI 53 trials. In the 1745 metformin-using participants matched to non-metformin users, metformin had neutral effects on MACE (hazard ratio [HR] 0.91, 95% confidence interval [CI] 0.76-1.08; P = 0.28) and ACM (HR 0.86, 95% CI 0.70-1.07; P = 0.18), with no interaction by CKD stage, or with use of exenatide or saxagliptin. An improvement in eGFR slope was observed with metformin in the CKD stage 3B cohort in SAVOR-TIMI 53, but not in other groups. CONCLUSIONS: This analysis of participants with CKD stages 3 to 4 from two cardiovascular outcomes trials supports the cardiorenal safety of metformin, but does not suggest a consistent benefit on MACE, ACM, or eGFR slope across this population.

A model-based approach to investigating the relationship between glucose-insulin dynamics and dapagliflozin treatment effect in patients with type 2 diabetes.

AIMS: To develop a quantitative systems pharmacology model to describe the effect of dapagliflozin (a sodium-glucose co-transporter-2 [SGLT2] inhibitor) on glucose-insulin dynamics in type 2 diabetes mellitus (T2DM) patients, and to identify key determinants of treatment-mediated glycated haemoglobin (HbA1c) reduction. MATERIALS AND METHODS: Glycaemic control during dapagliflozin treatment was mechanistically characterized by integrating components representing dapagliflozin pharmacokinetics (PK), glucose-insulin homeostasis, renal glucose reabsorption, and HbA1c formation. The model was developed using PK variables, glucose, plasma insulin, and urinary glucose excretion (UGE) from a phase IIa dapagliflozin trial in patients with T2DM (NCT00162305). The model was used to predict dapagliflozin-induced HbA1c reduction; model predictions were compared to actual data from phase III trials (NCT00528879, NCT00683878, NCT00680745 and NCT00673231). RESULTS: The integrated glucose-insulin-dapagliflozin model successfully described plasma glucose and insulin levels, as well as UGE in response to oral glucose tolerance tests and meal intake. HbA1c reduction was also well predicted. The results show that dapagliflozin-mediated glycaemic control is anticorrelated to steady-state insulin concentration and insulin sensitivity. CONCLUSIONS: The developed model framework is the first to integrate SGLT2 inhibitor mechanism of action with both short-term glucose-insulin dynamics and long-term glucose control (HbA1c). The results suggest that dapagliflozin treatment is beneficial in patients with inadequate glycaemic control from insulin alone and this benefit increases as insulin control diminishes.

Renal Effects of Dapagliflozin in People with and without Diabetes with Moderate or Severe Renal Dysfunction: Prospective Modeling of an Ongoing Clinical Trial.

Sodium glucose cotransporter 2 inhibitors (SGLT2i) reduce cardiovascular events and onset and progression of renal disease by mechanisms that remain incompletely understood but may include clearance of interstitial congestion and reduced glomerular hydrostatic pressure. The ongoing DAPASALT mechanistic clinical study will evaluate natriuretic, diuretic, plasma/extracellular volume, and blood pressure responses to dapagliflozin in people with type 2 diabetes with normal or impaired renal function (D-PRF and D-IRF, respectively) and in normoglycemic individuals with renal impairment (N-IRF). In this study, a mathematical model of renal physiology, pathophysiology, and pharmacology was used to prospectively predict changes in sodium excretion, blood and interstitial fluid volume (IFV), blood pressure, glomerular filtration rate, and albuminuria in DAPASALT. After validating the model with previous diabetic nephropathy trials, virtual patients were matched to DAPASALT inclusion/exclusion criteria, and the DAPASALT protocol was simulated. Predicted changes in glycosuria, blood pressure, glomerular filtration rate, and albuminuria were consistent with other recent studies in similar populations. Predicted albuminuria reductions were 46% in D-PRF, 34.8% in D-IRF, and 14.2% in N-IRF. The model predicts a similarly large IFV reduction between D-PRF and D-IRF and less, but still substantial, IFV reduction in N-IRF, even though glycosuria is attenuated in groups with impaired renal function. When DAPASALT results become available, comparison with these simulations will provide a basis for evaluating how well we understand the cardiorenal mechanism(s) of SGLT2i. Meanwhile, these simulations link dapagliflozin's renal mechanisms to changes in IFV and renal biomarkers, suggesting that these benefits may extend to those with impaired renal function and individuals without diabetes. SIGNIFICANCE STATEMENT: Mechanisms of SGLT2 inhibitors' cardiorenal benefits remain incompletely understood. We used a mathematical model of renal physiology/pharmacology to prospectively predict responses to dapagliflozin in the ongoing DAPASALT study. Key predictions include similarly large interstitial fluid volume (IFV) reductions between subjects with normal and impaired renal function and less, but still substantial, IFV reduction in those without diabetes, even though glycosuria is attenuated in these groups. Comparing prospective simulations and study results will assess how well we understand the cardiorenal mechanism(s) of SGLT2 inhibitors.

Prediction and validation of exenatide risk marker effects on progression of renal disease: Insights from EXSCEL.

AIM: To assess whether the previously developed multivariable risk prediction framework (PRE score) could predict the renal effects observed in the EXSCEL cardiovascular outcomes trial using short-term changes in cardio-renal risk markers. MATERIALS AND METHODS: Changes from baseline to 6 months in HbA1c, systolic blood pressure (SBP), body mass index (BMI), haemoglobin, total cholesterol, and new micro- or macroalbuminuria were evaluated. The renal outcomes were defined as a composite of a sustained 30% or 40% decline in estimated glomerular filtration rate (eGFR) or end-stage renal disease (ESRD). Relationships between risk markers and long-term renal outcomes were determined in patients with type 2 diabetes from the ALTITUDE study using multivariable Cox regression analysis, and then applied to short-term changes in risk markers observed in EXSCEL to predict the exenatide-induced impact on renal outcomes. RESULTS: Compared with placebo, mean HbA1c, BMI, SBP and total cholesterol were lower at 6 months with exenatide, as was the incidence of new microalbuminuria. The PRE score predicted a relative risk reduction for the 30% eGFR decline + ESRD endpoint of 11.3% (HR 0.89; 95% CI 0.83-0.94), compared with 12.7% (HR 0.87; 0.77-0.99) observed risk reduction. For the 40% eGFR decline + ESRD endpoint, the predicted and observed risk reductions were 11.0% (HR 0.89; 0.82-0.97) and 13.7% (HR 0.86, 0.72-1.04), respectively. CONCLUSIONS: Integrating short-term risk marker changes into a multivariable risk score predicted the magnitude of renal risk reduction observed in EXSCEL.

Effect of once-weekly exenatide on estimated glomerular filtration rate slope depends on baseline renal risk: A post hoc analysis of the EXSCEL trial.

The effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on renal outcomes in patients with type 2 diabetes at high cardiovascular risk are modest or neutral. However, GLP-1RAs may confer clinical benefits in those at high risk of progressive renal function loss. We examined the effects of once-weekly exenatide (EQW) on estimated glomerular filtration rate (eGFR) slope and urinary albumin:creatinine ratio (UACR) as a function of baseline UACR in 3503 EXSCEL participants (23.7%) with eGFR data available and 2828 participants (19.2%) with UACR change data available. EQW improved eGFR slope assessed via mixed model repeated measures, compared with placebo, in participants with baseline UACR >100 mg/g (0.79 mL/min/1.73 m2 /year [95% confidence interval {CI} 0.24-1.34]) and UACR >200 mg/g (1.32 mL/min/1.73 m2 /year [95% CI 0.57-2.06]), but not at lower UACR thresholds. EQW reduced UACR, compared with placebo, assessed via analysis of covariance, consistently across subgroups with baseline UACR >30 mg/g (28.2% reduction), baseline UACR >100 mg (22.5% reduction) and baseline UACR >200 mg (34.5% reduction). This post hoc EXSCEL analysis suggests that EQW reduces UACR, with improvement in eGFR slope specifically in participants with elevated baseline UACR.

Effect of Dapagliflozin on Worsening Heart Failure and Cardiovascular Death in Patients With Heart Failure With and Without Diabetes.

Importance: Additional treatments are needed for heart failure with reduced ejection fraction (HFrEF). Sodium-glucose cotransporter 2 (SGLT2) inhibitors may be an effective treatment for patients with HFrEF, even those without diabetes. Objective: To evaluate the effects of dapagliflozin in patients with HFrEF with and without diabetes. Design, Setting, and Participants: Exploratory analysis of a phase 3 randomized trial conducted at 410 sites in 20 countries. Patients with New York Heart Association classification II to IV with an ejection fraction less than or equal to 40% and elevated plasma N-terminal pro B-type natriuretic peptide were enrolled between February 15, 2017, and August 17, 2018, with final follow-up on June 6, 2019. Interventions: Addition of once-daily 10 mg of dapagliflozin or placebo to recommended therapy. Main Outcomes and Measures: The primary outcome was the composite of an episode of worsening heart failure or cardiovascular death. This outcome was analyzed by baseline diabetes status and, in patients without diabetes, by glycated hemoglobin level less than 5.7% vs greater than or equal to 5.7%. Results: Among 4744 patients randomized (mean age, 66 years; 1109 [23%] women; 2605 [55%] without diabetes), 4742 completed the trial. Among participants without diabetes, the primary outcome occurred in 171 of 1298 (13.2%) in the dapagliflozin group and 231 of 1307 (17.7%) in the placebo group (hazard ratio, 0.73 [95% CI, 0.60-0.88]). In patients with diabetes, the primary outcome occurred in 215 of 1075 (20.0%) in the dapagliflozin group and 271 of 1064 (25.5%) in the placebo group (hazard ratio, 0.75 [95% CI, 0.63-0.90]) (P value for interaction = .80). Among patients without diabetes and a glycated hemoglobin level less than 5.7%, the primary outcome occurred in 53 of 438 patients (12.1%) in the dapagliflozin group and 71 of 419 (16.9%) in the placebo group (hazard ratio, 0.67 [95% CI, 0.47-0.96]). In patients with a glycated hemoglobin of at least 5.7%, the primary outcome occurred in 118 of 860 patients (13.7%) in the dapagliflozin group and 160 of 888 (18.0%) in the placebo group (hazard ratio, 0.74 [95% CI, 0.59-0.94]) (P value for interaction = .72). Volume depletion was reported as an adverse event in 7.3% of patients in the dapagliflozin group and 6.1% in the placebo group among patients without diabetes and in 7.8% of patients in the dapagliflozin group and 7.8% in the placebo group among patients with diabetes. A kidney adverse event was reported in 4.8% of patients in the dapagliflozin group and 6.0% in the placebo group among patients without diabetes and in 8.5% of patients in the dapagliflozin group and 8.7% in the placebo group among patients with diabetes. Conclusions and Relevance: In this exploratory analysis of a randomized trial of patients with HFrEF, dapagliflozin compared with placebo, when added to recommended therapy, significantly reduced the risk of worsening heart failure or cardiovascular death independently of diabetes status. Trial Registration: ClinicalTrials.gov Identifier: NCT03036124.

Effects of exenatide and open-label SGLT2 inhibitor treatment, given in parallel or sequentially, on mortality and cardiovascular and renal outcomes in type 2 diabetes: insights from the EXSCEL trial.

BACKGROUND: Sodium-glucose cotransporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1 RA) improve cardiovascular and renal outcomes in patients with type 2 diabetes through distinct mechanisms. However, evidence on clinical outcomes in patients treated with both GLP-1 RA and SGLT2i is lacking. We aim to provide insight into the effects of open-label SGLT2i use in parallel with or shortly after once-weekly GLP-1 RA exenatide (EQW) on cardiorenal outcomes. METHODS: In the EXSCEL cardiovascular outcomes trial EQW arm, SGLT2i drop-in occurred in 8.7% of participants. These EQW+SGLT2i users were propensity-matched to: (1) placebo-arm participants not taking SGLT2i (n = 572 per group); and to (2) EQW-arm participants not taking SGLT2i (n = 575), based on their last measured characteristics before SGLT2i initiation, and equivalent study visit in comparator groups. Time-to-first major adverse cardiovascular event (MACE) and all-cause mortality (ACM) were compared using Cox regression analyses. eGFR slopes were quantified using mixed model repeated measurement analyses. RESULTS: In adjusted analyses, the risk for MACE with combination EQW+SGLT2i use was numerically lower compared with both placebo (adjusted hazard ratio 0.68, 95% CI 0.39-1.17) and EQW alone (0.85, 0.48-1.49). Risk of ACM was nominally significantly reduced compared with placebo (0.38, 0.16-0.90) and compared with EQW (0.41, 0.17-0.95). Combination EQW+SGLT2i use also nominally significantly improved estimated eGFR slope compared with placebo (+ 1.94, 95% CI 0.94-2.94 mL/min/1.73 m2/year) and EQW alone (+ 2.38, 1.40-3.35 mL/min/1.73 m2/year). CONCLUSIONS: This post hoc analysis supports the hypothesis that combinatorial EQW and SGLT2i therapy may provide benefit on cardiovascular outcomes and mortality. Trial registration Clinicaltrials.gov, Identifying number: NCT01144338, Date of registration: June 15, 2010.

Model-based characterization of the relationship between dapagliflozin systemic exposure and HbA1c response in patients with type 1 diabetes mellitus.

AIMS: To quantitatively describe the relationship between dapagliflozin systemic exposure and HbA1c response among patients with type 1 diabetes mellitus (T1DM) and assess the potential impact of covariate effects. MATERIALS AND METHODS: Individual longitudinal HbA1c data from two phase 3 studies in patients with T1DM (24-week treatment with once-daily dapagliflozin 5 or 10 mg or placebo, with adjustable insulin) were analyzed using a non-linear mixed effect modeling approach. Area under the concentration curve was used to measure dapagliflozin systemic exposure. Baseline HbA1c, estimated glomerular filtration rate, reduction in total insulin dose, baseline glucose concentrations, age, sex, race (Asian vs. non-Asian), and insulin administration method (multiple daily injections vs. insulin pump) were assessed as covariates. RESULTS: A maximum effect (Emax ) model identified a positive exposure-response relationship. Model-predicted placebo-corrected HbA1c reductions after 24 weeks for dapagliflozin 5- and 10-mg doses were - 0.42% [95% confidence interval (CI) -0.47 to -0.36) and - 0.45% (95% CI -0.50 to -0.40), respectively; baseline HbA1c was ~8.4%. This was in good agreement with actual observations from both studies. Baseline HbA1c was a significant covariate: patients with higher baseline HbA1c were predicted to have greater HbA1c reductions. CONCLUSIONS: The relationship between dapagliflozin systemic exposure and HbA1c response was successfully described in patients with T1DM. None of the tested covariates affected the efficacy of dapagliflozin to a clinically relevant extent. Therefore, no dose adjustment of dapagliflozin is required in patients with T1DM based on the tested covariates. ClinicalTrials.gov, NCT02268214; NCT02460978.

Pharmacokinetics and pharmacodynamics of dapagliflozin in combination with insulin in Japanese patients with type 1 diabetes.

AIMS: To assess the pharmacokinetics/pharmacodynamics (PK/PD) of dapagliflozin, a sodium-glucose co-transporter 2 inhibitor that increases urinary glucose excretion (UGE) and its major metabolite, dapagliflozin-3-O-glucuronide (D3OG), in Japanese patients with type 1 diabetes (T1D) and inadequate glycaemic control (HbA1c 7%-10%). MATERIALS AND METHODS: Japanese patients (18-65 years) with inadequately controlled T1D were randomized 1:1:1 to dapagliflozin 5 mg, 10 mg or placebo (n = 14 each) once daily for 7 days, with adjustable insulin. The PK/PD characteristics of dapagliflozin and D3OG were assessed on Day 7. Patients underwent follow-up evaluation on Days 8 and 14. Adverse events (AEs), hypoglycaemic episodes and events of diabetic ketoacidosis (DKA) were recorded over the treatment and follow-up periods. RESULTS: A total of 42 randomized patients received dapagliflozin or placebo. PK variables increased in a dose-dependent manner. D3OG was generated rapidly, with a median time to maximum plasma concentration of 2.0 hours (1.0-3.0). The dapagliflozin dose-UGE relationship was attenuated, with larger insulin dose reductions than anticipated. Mean percent (standard error) changes in total daily insulin dose from baseline to Day 7 were - 36.86% (3.32), -39.13% (2.68) and - 4.97% (5.28) for dapagliflozin 5 mg and 10 mg and for placebo, respectively. No DKA was reported. AEs were consistent with the established dapagliflozin safety profile. There was no increase in hypoglycaemia. CONCLUSIONS: The PK and safety profiles of dapagliflozin in Japanese patients with T1D were consistent with previous studies, but with an unanticipated attenuation of the PD dose-response measured as UGE.

Urinary glucose excretion after dapagliflozin treatment: An exposure-response modelling comparison between Japanese and non-Japanese patients diagnosed with type 1 diabetes mellitus.

AIMS: To assess the dapagliflozin exposure-response relationship in Japanese and non-Japanese patients with type 1 diabetes mellitus (T1DM) and investigate if a dose adjustment is required in Japanese patients. MATERIALS AND METHODS: Data from two clinical studies were used to develop a non-linear mixed effects model describing the relationship between dapagliflozin exposure (area under the concentration curve) and response (24-hour urinary glucose excretion [UGE]) in Japanese and non-Japanese patients with T1DM. The effects of patient-level characteristics (covariates; identified using a stepwise procedure) on response was also assessed. Simulations were performed using median-normalized covariate values. RESULTS: Data from 84 patients were included. Average self-monitored blood glucose (SMBG) at day 7, change from baseline in total insulin dose at day 7, and baseline estimated glomerular filtration rate (eGFR) all had a significant effect on 24-hours UGE, with SMBG being the most influential. Dapagliflozin systemic exposure for matching doses and baseline eGFR was similar between Japanese and non-Japanese patients; however, higher SMBG and a greater reduction in total insulin dose was observed in the Japanese population. When the significant covariates were included, the model fit the data well for both populations, and accurately predicted exposure-response in the Japanese and non-Japanese populations, in agreement with the observed data. CONCLUSIONS: There was no difference in dapagliflozin exposure-response in Japanese and non-Japanese patients with T1DM once differences in renal function, glycaemic control and insulin dose reductions between studies were considered. Therefore, no dose adjustment is recommended in Japanese patients with T1DM.

Effects of the sodium-glucose co-transporter-2 inhibitor dapagliflozin on estimated plasma volume in patients with type 2 diabetes.

AIMS: To compare the effects of the sodium-glucose co-transporter-2 (SGLT2) inhibitor dapagliflozin on estimated (ePV) and measured plasma volume (mPV) and to characterize the effects of dapagliflozin on ePV in a broad population of patients with type 2 diabetes. MATERIALS AND METHODS: The Strauss formula was used to calculate changes in ePV. Change in plasma volume measured with 125 I-human serum albumin (mPV) was compared with change in ePV in 10 patients with type 2 diabetes randomized to dapagliflozin 10 mg/d or placebo. Subsequently, changes in ePV were measured in a pooled database of 13 phase 2b/3 placebo-controlled clinical trials involving 4533 patients with type 2 diabetes who were randomized to dapagliflozin 10 mg daily or matched placebo. RESULTS: The median change in ePV was similar to the median change in mPV (-9.4% and -9.0%) during dapagliflozin treatment. In the pooled analysis of clinical trials, dapagliflozin decreased ePV by 9.6% (95% confidence interval 9.0 to 10.2) compared to placebo after 24 weeks. This effect was consistent in various patient subgroups, including subgroups with or without diuretic use or established cardiovascular disease. CONCLUSIONS: ePV may be used as a proxy to assess changes in plasma volume during dapagliflozin treatment. Dapagliflozin consistently decreased ePV compared to placebo in a broad population of patients with type 2 diabetes.

Comparison of the urinary glucose excretion contributions of SGLT2 and SGLT1: A quantitative systems pharmacology analysis in healthy individuals and patients with type 2 diabetes treated with SGLT2 inhibitors.

AIM: To develop a quantitative drug-disease systems model to investigate the paradox that sodium-glucose co-transporter (SGLT)2 is responsible for >80% of proximal tubule glucose reabsorption, yet SGLT2 inhibitor treatment results in only 30% to 50% less reabsorption in patients with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: A physiologically based four-compartment model of renal glucose filtration, reabsorption and excretion via SGLT1 and SGLT2 was developed as a system of ordinary differential equations using R/IQRtools. SGLT2 inhibitor pharmacokinetics and pharmacodynamics were estimated from published concentration-time profiles in plasma and urine and from urinary glucose excretion (UGE) in healthy people and people with T2DM. RESULTS: The final model showed that higher renal glucose reabsorption in people with T2DM versus healthy people was associated with 54% and 28% greater transporter capacity for SGLT1 and SGLT2, respectively. Additionally, the analysis showed that UGE is highly dependent on mean plasma glucose and estimated glomerular filtration rate (eGFR) and that their consideration is critical for interpreting clinical UGE findings. CONCLUSIONS: Quantitative drug-disease system modelling revealed mechanistic differences in renal glucose reabsorption and UGE between healthy people and those with T2DM, and clearly showed that SGLT2 inhibition significantly increased glucose available to SGLT1 downstream in the tubule. Importantly, we found that the findings of lower than expected UGE with SGLT2 inhibition are explained by the shift to SGLT1, which recovered additional glucose (~30% of total).

Comparison of pharmacokinetics and the exposure-response relationship of dapagliflozin between adolescent/young adult and adult patients with type 1 diabetes mellitus.

AIMS: To quantitatively compare pharmacokinetics (PK) and the exposure-response (ER) relationship of the sodium-glucose cotransporter-2 inhibitor, dapagliflozin, between adolescents/young adults and adults with type 1 diabetes mellitus (T1DM). METHODS: Data from 2 clinical studies for dapagliflozin were analysed using a non-linear mixed-effects approach. The PK and the relationship between dapagliflozin exposure and response (24-hour urinary glucose excretion) were characterized. PK was evaluated using a 2-compartment model with first-order absorption while the exposure response-relationship was analysed using a sigmoidal maximal-effect model. The 24-hour median blood glucose, estimated glomerular filtration rate (eGFR), sex, age and body weight were evaluated as covariates. RESULTS: A 2-compartment model with first order absorption provided a reasonable fit to the dapagliflozin PK data. Body weight was found to be a significant covariate on dapagliflozin exposure. The ER relationship was best described by a sigmoidal maximal effect model with 24-hour median blood glucose and eGFR as significant covariates on maximal effect. In accordance with the observed data, model-predicted urinary glucose excretion response following 10 mg dapagliflozin dose was higher in the study in adolescents/young adults (138.0 g/24 h) compared to adults (70.5 g/24 h) with T1DM. This is linked to higher eGFR and 24-hour median blood glucose in this trial. CONCLUSIONS: Dapagliflozin PK and ER relationship were similar in the 2 analysed studies after accounting for covariate effects. These results suggest that no dose adjustment is required for adolescent patients with T1DM.

Evaluation of renal and cardiovascular protection mechanisms of SGLT2 inhibitors: model-based analysis of clinical data.

The mechanisms of cardiovascular and renal protection observed in clinical trials of sodium-glucose cotransporter 2 (SGLT2) inhibitors (SGLT2i) are incompletely understood and likely multifactorial, including natriuretic, diuretic, and antihypertensive effects, glomerular pressure reduction, and lowering of plasma and interstitial fluid volume. To quantitatively evaluate the contribution of proposed SGLT2i mechanisms of action on changes in renal hemodynamics and volume status, we coupled a mathematical model of renal function and volume homeostasis with clinical data in healthy subjects administered 10 mg of dapagliflozin once daily. The minimum set of mechanisms necessary to reproduce observed clinical responses (urinary sodium and water excretion, serum creatinine and sodium) was determined, and important unobserved physiological variables (glomerular pressure, blood and interstitial fluid volume) were then simulated. We further simulated the response to SGLT2i in diabetic virtual patients with and without renal impairment. Multiple mechanisms were required to explain the observed response: 1) direct inhibition of sodium and glucose reabsorption through SGLT2, 2) SGLT2-driven inhibition of Na+/H+ exchanger 3 sodium reabsorption, and 3) osmotic diuresis coupled with peripheral sodium storage. The model also showed that the consequences of these mechanisms include lowering of glomerular pressure, reduction of blood and interstitial fluid volume, and mild blood pressure reduction, in agreement with clinical observations. The simulations suggest that these effects are more significant in diabetic patients than healthy subjects and that while glucose excretion may diminish with renal impairment, improvements in glomerular pressure and blood volume are not diminished at lower glomerular filtration rate, suggesting that cardiorenal benefits of SGLT2i may be sustained in renally impaired patients.

Why do SGLT2 inhibitors reduce heart failure hospitalization? A differential volume regulation hypothesis.

The effect of a sodium glucose cotransporter 2 inhibitor (SGLT2i) in reducing heart failure hospitalization in the EMPA-REG OUTCOMES trial has raised the possibility of using these agents to treat established heart failure. We hypothesize that osmotic diuresis induced by SGLT2 inhibition, a distinctly different diuretic mechanism than that of other diuretic classes, results in greater electrolyte-free water clearance and, ultimately, in greater fluid clearance from the interstitial fluid (IF) space than from the circulation, potentially resulting in congestion relief with minimal impact on blood volume, arterial filling and organ perfusion. We utilize a mathematical model to illustrate that electrolyte-free water clearance results in a greater reduction in IF volume compared to blood volume, and that this difference may be mediated by peripheral sequestration of osmotically inactive sodium. By coupling the model with data on plasma and urinary sodium and water in healthy subjects who received either the SGLT2i dapagliflozin or loop diuretic bumetanide, we predict that dapagliflozin produces a 2-fold greater reduction in IF volume compared to blood volume, while the reduction in IF volume with bumetanide is only 78% of the reduction in blood volume. Heart failure is characterized by excess fluid accumulation, in both the vascular compartment and interstitial space, yet many heart failure patients have arterial underfilling because of low cardiac output, which may be aggravated by conventional diuretic treatment. Thus, we hypothesize that, by reducing IF volume to a greater extent than blood volume, SGLT2 inhibitors might provide better control of congestion without reducing arterial filling and perfusion.

Exenatide effects on gastric emptying rate and the glucose rate of appearance in plasma: A quantitative assessment using an integrative systems pharmacology model.

This study aimed to quantify the effect of the immediate release (IR) of exenatide, a short-acting glucagon-like peptide-1 (GLP-1) receptor agonist (GLP-1RA), on gastric emptying rate (GER) and the glucose rate of appearance (GluRA), and evaluate the influence of drug characteristics and food-related factors on postprandial plasma glucose (PPG) stabilization under GLP-1RA treatment. A quantitative systems pharmacology (QSP) approach was used, and the proposed model was based on data from published sources including: (1) GLP-1 and exenatide plasma concentration-time profiles; (2) GER estimates under placebo, GLP-1 or exenatide IR dosing; and (3) GluRA measurements upon food intake. According to the model's predictions, the recommended twice-daily 5- and 10-µg exenatide IR treatment is associated with GluRA flattening after morning and evening meals (48%-49%), whereas the midday GluRA peak is affected to a lesser degree (5%-30%) due to lower plasma drug concentrations. This effect was dose-dependent and influenced by food carbohydrate content, but not by the lag time between exenatide injection and meal ingestion. Hence, GER inhibition by exenatide IR represents an important additional mechanism of its effect on PPG.