Pharmacokinetics of Daprodustat and Metabolites in Individuals with Normal and Impaired Hepatic Function.

Daprodustat is a hypoxia-inducible factor-prolyl hydroxylase inhibitor in development for treatment of anemia of chronic kidney disease. We evaluated the role of hepatic impairment on daprodustat pharmacokinetics, pharmacodynamics, and tolerability. Participants with mild (Child-Pugh Class A, score 5-6) and moderate (Child-Pugh Class B, score 7-9) hepatic impairment and matched healthy controls were administered single 6-mg doses of daprodustat. Exposure parameters were determined for daprodustat and its six metabolites. Comparisons resulted in 1.5- and 2.0-fold higher daprodustat Cmax and area under the curve (AUC) exposures in participants with mild and moderate hepatic impairment, respectively, versus controls; Cmax in mild hepatic impairment was comparable to controls. Similarly, aligned with parent drug, unbound daprodustat Cmax and AUC exposures increased 1.6- to 2.3-fold in hepatic-impaired participants versus controls, and metabolite exposures were 1.2- to 2.0-fold higher in participants with hepatic impairment. Erythropoeitin (EPO) baseline-corrected AUC exposures were between 0.3-fold lower and 2.2-fold higher in matched controls versus hepatic-impaired participants. No serious or study drug-related adverse events were reported. Daprodustat exposure was increased in participants with moderate and mild hepatic impairment compared with matched controls; however, no meaningful differences in EPO were observed and no new safety concerns were identified (ClinicalTrials.gov: NCT03223337).

Efficacy and safety of an albiglutide liquid formulation compared with the lyophilized formulation: A 26-week randomized, double-blind, repeat-dose study in patients with type 2 diabetes mellitus.

AIMS: Compare the efficacy and safety of albiglutide from a ready-to-use, single-dose, auto-injector system with the lyophilized product in patients with type 2 diabetes mellitus (T2DM). METHODS: In this phase 3 study, 308 patients between 18 and 80 years with T2DM and experiencing inadequate glycemic control on their current regimen of diet/exercise alone or in combination with metformin were randomized 1:1 to weekly injections for 26 weeks with an active albiglutide auto-injector and placebo lyophilized dual-chamber cartridge (DCC) pen injector (n = 154) or active albiglutide lyophilized DCC pen injector and placebo liquid auto-injector (n = 154). Participants received liquid or lyophilized albiglutide 30 mg for 4 weeks, and then 50 mg for the remaining 22 weeks. Change in HbA1c and fasting plasma glucose (FPG), pharmacokinetics, and safety were assessed. RESULTS: In the albiglutide liquid and lyophilized drug product groups, 55.6% (85/153) and 45.5% of patients (70/154) had a baseline HbA1c ≥ 8.0%, respectively. The model-adjusted least squares (LS) mean change in HbA1c from baseline at week 26 was -1.1% (95% CI: -1.3, -1.0) and -1.2% (95% CI: -1.3, -1.0; noninferiority P = 0.0002) in the albiglutide liquid and lyophilized product groups, respectively. Similarly, the model-adjusted LS mean change in FPG from baseline at week 26 in the albiglutide liquid and lyophilized product groups was -2.2 (95% CI: -2.6, -1.8) mmol/L and -1.9 (95% CI: -2.3, -1.5) mmol/L, respectively. No new safety concerns were identified. CONCLUSION: Change from baseline in HbA1c for albiglutide liquid was noninferior to lyophilized drug product in patients with T2DM.

A Randomized, Double-Blind, Single-Dose, Crossover Study to Demonstrate the Bioequivalence of 2 Formulations of Albiglutide in Healthy Adult Participants.

Albiglutide, developed for treatment of type 2 diabetes mellitus, is provided in a dual-chamber cartridge (DCC) single-dose pen-injector containing lyophilized drug that must be reconstituted with diluent prior to use. A liquid formulation of albiglutide has been developed that does not require mixing. In this 2-period, randomized, crossover, double-blind, phase I study (NCT02660736) in 59 healthy volunteers, pharmacokinetic parameters were determined and the bioequivalence of the 2 formulations was assessed. Participants received injections from each type of pen-injector, one containing albiglutide 50 mg and one containing placebo, followed by an 8-week washout period between regimens: albiglutide 50-mg liquid formulation from an auto-injector and lyophilized placebo from a DCC pen-injector (Regimen A), or placebo liquid from an auto-injector and lyophilized albiglutide 50 mg from a DCC pen-injector (Regimen B). Geometric mean total exposures (area under the drug concentration-time curve [AUC](0-t) [1345.4 vs 1426.9 (µg · h/mL)], AUC(0-∞) [1376.2 vs 1454.6 (µg · h/mL)], and maximum concentration of drug in blood plasma [4968.5 vs 5314.7 ng/mL]) were comparable between Regimens A and B. Ratios of geometric least square means (90% confidence interval) were 95.3% (89.49-101.52) for AUC(0-∞) , 95.1% (89.12-101.49) for AUC(0-t) , and 93.2% (86.76-100.17) for maximum concentration of drug in blood plasma, falling within the 90% confidence interval of 0.80 to 1.25 for bioequivalence. No new safety concerns were observed.

Effect of Albiglutide on Cholecystokinin-Induced Gallbladder Emptying in Healthy Individuals: A Randomized Crossover Study.

The glucagon-like peptide-1 (GLP-1) receptor agonists (RAs) exenatide and lixisenatide reduce cholecystokinin (CCK)-induced gallbladder emptying in healthy subjects. It is unknown if all GLP-1 RAs share this effect; therefore, the effect of the GLP-1 RA albiglutide on gallbladder function was assessed. In this randomized, double-blind, 2-way crossover study, a single dose of subcutaneous albiglutide 50 mg or placebo was administered to 17 healthy subjects, and CCK-induced gallbladder contractility was measured by ultrasonography. CCK (0.003 µg/kg) was infused intravenously over 50 minutes on study day 4 (3 days after dosing, to coincide with albiglutide's expected time to maximum concentration). Gallbladder volume, ejection fraction, and the main pancreatic and common bile-duct diameters were measured before, during, and following CCK infusion. Gallbladder volume was significantly greater in the albiglutide vs placebo groups before, during, and after CCK infusion, and the mean difference from placebo increased numerically during CCK infusion. The area under the volume-effect curve was significantly greater with albiglutide (P = .029). Starting at the 30-minute CCK infusion time point, the gallbladder ejection fraction was significantly lower with albiglutide than placebo. Changes in pancreatic duct diameter and common bile-duct diameter were not significantly different between albiglutide and placebo. Similar incidences of adverse events were observed between the albiglutide and placebo treatment periods. No new albiglutide safety signals were detected, and no serious adverse events were reported. In conclusion, similar to other GLP-1 RAs, albiglutide decreased CCK-induced gallbladder emptying compared with placebo in healthy individuals. Clinical implications of the gallbladder effects are unclear at this time.

Platelet aggregation unchanged by lipoprotein-associated phospholipase A2 inhibition: results from an in vitro study and two randomized phase I trials.

BACKGROUND: We explored the theorized upregulation of platelet-activating factor (PAF)- mediated biologic responses following lipoprotein-associated phospholipase A2 (Lp-PLA2) inhibition using human platelet aggregation studies in an in vitro experiment and in 2 clinical trials. METHODS AND RESULTS: Full platelet aggregation concentration response curves were generated in vitro to several platelet agonists in human plasma samples pretreated with rilapladib (selective Lp-PLA2 inhibitor) or vehicle. This was followed by a randomized, double-blind crossover study in healthy adult men (n = 26) employing a single-agonist dose assay of platelet aggregation, after treatment of subjects with 250 mg oral rilapladib or placebo once daily for 14 days. This study was followed by a second randomized, double-blind parallel-group trial in healthy adult men (n = 58) also treated with 250 mg oral rilapladib or placebo once daily for 14 days using a full range of 10 collagen concentrations (0-10 µg/ml) for characterizing EC50 values for platelet aggregation for each subject. Both clinical studies were conducted at the GlaxoSmithKline Medicines Research Unit in the Prince of Wales Hospital, Sydney, Australia. EC50 values derived from multiple agonist concentrations were compared and no pro-aggregant signals were observed during exposure to rilapladib in any of these platelet studies, despite Lp-PLA2 inhibition exceeding 90%. An increase in collagen-mediated aggregation was observed 3 weeks post drug termination in the crossover study (15.4% vs baseline; 95% confidence interval [CI], 3.9-27.0), which was not observed during the treatment phase and was not observed in the parallel-group study employing a more robust EC50 examination. CONCLUSIONS: Lp-PLA2 inhibition does not enhance platelet aggregation. TRIAL REGISTRATION: 1) Study 1: ClinicalTrials.gov NCT01745458 2) Study 2: ClinicalTrials.gov NCT00387257.

Evaluation of vardenafil and sildenafil on cardiac repolarization.

This novel study evaluated the effects of vardenafil and sildenafil on QT and corrected QT (QTc) duration using a model that minimizes experimental error to obtain the most accurate assessment of observed QTc effects. A placebo-controlled and positive-controlled, period-balanced, double-blinded, 6-way crossover study evaluated therapeutic and supratherapeutic oral doses of vardenafil (10 and 80 mg, respectively) and sildenafil (50 and 400 mg, respectively), therapeutic doses of moxifloxacin (400 mg), and a placebo in 58 healthy men (mean age 53 years), with dosing every 3 days. Six replicate, 12-lead, digital electrocardiograms (ECGs) were recorded at 3 time points before and 5 time points after dosing to cover the time course of maximum exposure to study drugs and their metabolites. An independent laboratory blindly analyzed approximately 17,000 ECGs. For the placebo, mean change in QTcF (Fridericia) duration 1 hour after dose (approximate Tmax of vardenafil and sildenafil) was 0 ms (+/-0.7 SD). QT/QTc variability was small across regimens, indicating statistically powerful results. Moxifloxacin demonstrated an expected 8-ms mean change and was the only drug to prolong absolute QT. Placebo-corrected mean changes in QTcF duration (90% confidence interval) at 1 hour after dose were 8 ms (range 6 to 9) for vardenafil 10 mg and 6 ms (range 5 to 8) for sildenafil 50 mg. QTci (linear and nonlinear per patient) yielded similar trends: 4 ms (range 3 to 6) for vardenafil 10 mg and 4 ms (range 2 to 5) for sildenafil 50 mg. Dose response demonstrated very shallow QTc relations for study drugs. Therapeutic and supratherapeutic doses produced only small increases in the QTcF interval, which were considered to be clinically irrelevant. This well-controlled, statistically powerful study in middle-aged men demonstrated that vardenafil and sildenafil produced no increase of absolute QT and only similar, small increases of the QTc interval, with a shallow dose-response curve. The study design and conduct may serve as a guide for future QT assessment of new drugs.