Pharmacokinetics, Safety, and Tolerability of Vonoprazan- or Esomeprazole-Based Bismuth-Containing Quadruple Therapy: A Phase 1, Double-Blind, Parallel-Group Study in Adults with Helicobacter pylori Infection in China.

Quadruple therapy comprising 2 antibiotics, a proton pump inhibitor, and bismuth, is recommended for Helicobacter pylori eradication in China. This Phase 1, double-blind, parallel-group study aimed to evaluate the pharmacokinetics, safety, and tolerability of bismuth-containing vonoprazan- or esomeprazole-based quadruple therapy in H. pylori-positive healthy subjects at a single site in China. Quadruple therapy comprising vonoprazan 20 mg or esomeprazole 20 mg with bismuth potassium citrate 600 mg (equivalent to bismuth 220 mg), clarithromycin 500 mg, and amoxicillin 1000 mg was administered twice daily for 2 weeks. Forty-four subjects were enrolled, 22 each in the vonoprazan (mean age, 34.5 years; men, 63.6%) and esomeprazole (mean age, 31.6 years; men, 59.1%) groups. Day 14 bismuth plasma pharmacokinetic parameters area under the plasma concentration-time curve during a dosing interval (geometric mean ratio, 1.07 [90% confidence interval, 0.82-1.40]) and maximum observed plasma concentration (geometric mean ratio, 1.30 [90% confidence interval, 0.94-1.81]) were similar between the treatment groups. At Day 42 follow-up, 100% and 94.4% of subjects were H. pylori negative in the vonoprazan and esomeprazole groups, respectively. The incidence of treatment-emergent adverse events was similar between the groups, with no serious adverse events. No new safety concerns were identified. In conclusion, vonoprazan had no significant effect on plasma bismuth exposure compared with esomeprazole.

Randomized clinical trial: A double-blind, proof-of-concept, phase 2 study evaluating the efficacy and safety of vonoprazan 20 or 40 mg versus esomeprazole 40 mg in patients with symptomatic gastro-esophageal reflux disease and partial response to a healing dose of a proton-pump inhibitor.

BACKGROUND: Proton-pump inhibitors (PPIs) are cornerstone treatments for gastro-esophageal reflux disease (GERD); however, evidence suggests that most patients exhibit partial response to PPIs, suggesting the need for novel therapies that can provide an improved and sustained increase in gastric pH. AIMS: This study aimed to determine the effect of vonoprazan, a novel, orally active small-molecule potassium-competitive acid blocker, versus esomeprazole, a PPI, in preventing heartburn symptoms over a 4-week treatment period in patients with GERD and a partial response to esomeprazole treatment. METHODS: This randomized, double-blind, proof-of-concept, phase 2 clinical trial was conducted between 2016 and 2018 at 39 sites across Europe and designed to evaluate the efficacy and safety of vonoprazan 20 mg once daily (q.d.) and 40 mg q.d. versus esomeprazole 40 mg q.d. after 1:1:1 randomization of symptomatic patients with GERD and a partial response to a healing dose of esomeprazole. RESULTS: Overall, 256 eligible patients (female, 59.4%; mean age, 52.6 years) received vonoprazan 20 mg (n = 85), vonoprazan 40 mg (n = 85), or esomeprazole 40 mg (n = 86); mean (SD) percentages of heartburn-free 24-h periods during double-blind treatment were 36.7% (33.4%), 36.5% (35.6%), and 38.4% (34.8%), respectively, with no intergroup statistical significance. Vonoprazan exposure increased proportionally from the 20-mg to 40-mg dose (mean Cmax : 23.3 ng/ml to 47.1 ng/ml, respectively). Most treatment-emergent adverse events were mild, with no deaths reported. CONCLUSIONS: No statistically significant difference in efficacy and safety was observed among treatment groups, and vonoprazan was well tolerated. The trial is registered with the National Board of Health (EudraCT: 2015-001154-14) database.

The Effect of Hepatic Impairment on the Pharmacokinetics of Intravenously Administered Felcisetrag (TAK-954).

Felcisetrag (formerly known as TAK-954) is a selective serotonin receptor agonist under investigation for use in patients with postoperative gastrointestinal dysfunction. The safety, tolerability, and pharmacokinetics (PK) of intravenous (i.v.) felcisetrag have been studied, but little is known about the effect of hepatic impairment on the PK of the drug. This phase 1, non-randomized, open-label study compared the PK of a single 60-minute i.v. infusion of felcisetrag between healthy individuals (n = 8) and patients with moderate (n = 10) or severe (n = 7) hepatic impairment. The primary study end points were the total and free maximum observed plasma concentration of felcisetrag at the end of infusion (Cmax ), area under the concentration-time curve (AUC) from time 0 to the time of the last quantifiable concentration (AUClast ), and AUC from time 0 to infinity (AUCinf ). Concentration-time profiles of felcisetrag were similarly shaped between groups but revealed lower concentrations of total plasma felcisetrag with increasing severity of hepatic impairment, whereas concentrations of free felcisetrag increased. The ratios of AUClast and AUCinf for patients with severe hepatic impairment were up to 29.3% lower for total felcisetrag and up to 29.2% higher for free felcisetrag than found in healthy individuals (P < .05). Infusions were well tolerated with no discontinuations, severe adverse events, or deaths during the study. Overall, the effect of hepatic impairment on exposure to felcisetrag was minimal, suggesting that dose adjustment may be unnecessary in patients with hepatic impairment.

Clinical and Nonclinical Disposition and In Vitro Drug-Drug Interaction Potential of Felcisetrag, a Highly Selective and Potent 5-HT4 Receptor Agonist.

BACKGROUND AND OBJECTIVE: Felcisetrag (previously TAK-954 or TD-8954) is a highly selective and potent 5-HT4 receptor agonist in clinical development for prophylaxis and treatment of postoperative gastrointestinal dysfunction (POGD). The rat, dog, and human absorption, distribution, metabolism, and excretion (ADME) properties of felcisetrag were investigated. METHODS: The metabolism and victim and perpetrator drug interaction potentials towards cytochrome P450s (CYP) and transporters were determined using in vitro models. The excretion, metabolite profile, and pharmacokinetics were determined during unlabeled and radiolabeled ADME studies in rat and dog for comparison with human. Due to a low clinical dose (0.5 mg) and radioactivity (~ 1.5 µCi), a combination of liquid scintillation counting and accelerator mass spectrometry was used for analysis of samples in this study. RESULTS: The ADME properties, including metabolite profile, for felcisetrag are generally conserved across species. Felcisetrag is primarily cleared through renal excretion (0.443) and metabolism in humans (0.420), with intact parent as the predominant species in circulation. There are multiple metabolites, each representing < 10% of the circulating radioactivity, confirming no metabolites in safety testing (MIST) liabilities. Metabolites were also detected in animals. The potential for major CYP- and transporter-based drug-drug interaction (DDI) of felcisetrag as a victim or perpetrator is considered to be low. CONCLUSIONS: Felcisetrag is primarily cleared in humans through renal excretion. Although the metabolism of felcisetrag is primarily through CYP3A, the potential for clinically relevant DDI as a victim is significantly reduced as metabolism plays a minor role in the overall clearance.

Characterizing Effects of Antidiabetic Drugs on Heart Rate, Systolic and Diastolic Blood Pressure.

A model-based meta-analysis was performed with reported data from obese subjects and patients with type 2 diabetes (T2DM) to characterize the effects of dipeptidyl peptidase 4 (DPP4) inhibitors, gastric inhibitory polypeptides (GIPs), glucagon-like peptide-1 (GLP1), and dual GIP/GLP1 agonists, or a combination of these antidiabetic drugs (ADs) on heart rate (HR), diastolic blood pressure (DBP), and systolic blood pressure (SBP). A systematic literature search and review after the Cochrane method identified sources for investigational and approved ADs resulted in a comprehensive database with data from 178 clinical studies in obese subjects and patients with T2DM. Results indicated that there were AD class-dependent effects on HR and SBP, whereas no clear AD-related effects on DBP were found. All AD classes, except for DPP4 inhibitors, increased HR. The largest increase of 12 bpm was seen with GLP1 receptor agonists. All AD classes appeared to decrease SBP. DPP4 inhibitors were associated with a marginal decrease of ~ 1 mmHg, whereas GLP1 and GIP/GLP1 dual agonists exhibited the largest decrease of ~ 3 mmHg in SBP. AD-related effects were similar in obese subjects and patients with T2DM. In conclusion, there are clinically relevant AD-related effects on both HR and SBP, but not on DBP. DPP4 inhibitors are associated with the smallest (if at all) effects on HR and SBP, whereas GLP1 inhibitors exhibited the largest effects on these two cardiovascular end points. Additional studies are warranted to further investigate how AD-related SBP decreases combined with HR increases affect long-term cardiovascular mortality.

Collaborations between Clinical Pharmacologists in Japan and in the United States - Report from the IQ CPLG and JPMA CPTF Meeting in Tokyo, Japan.

The International Consortium for Innovation and Quality in Pharmaceutical Development (IQ) Clinical Pharmacology Leadership Group (CPLG) held its first meeting of Japan-based representatives at Astellas Pharma headquarters in Tokyo on October 1, 2019. The meeting was also attended by Japan Pharmaceutical Manufactures Association (JPMA) Clinical Pharmacology Task Force (CPTF) members. Overall, nearly 30 clinical pharmacologists representing 14 companies attended the event. The meeting met its goal of enhancing mutual understanding of each organization's activities. In a number of break-out sessions, participants identified scientific topics for potential future collaboration between JPMA CPTF and IQ CPLG.

In Vitro Assessment of Potential for CYP-Inhibition-Based Drug-Drug Interaction Between Vonoprazan and Clopidogrel.

BACKGROUND AND OBJECTIVES: It was recently proposed that CYP-mediated drug-drug interactions (DDIs) of vonoprazan with clopidogrel and prasugrel can attenuate the antiplatelet actions of the latter two drugs. Clopidogrel is metabolized to the pharmacologically active metabolite H4 and its isomers by multiple CYPs, including CYP2C19 and CYP3A4. Therefore, to investigate the possibility of CYP-based DDIs, in vitro metabolic inhibition studies using CYP probe substrates or radiolabeled clopidogrel and human liver microsomes (HLMs) were conducted in this work. METHODS: Reversible inhibition studies focusing on the effects of vonoprazan on CYP marker activities and the formation of the [14C]clopidogrel metabolite H4 were conducted with and without pre-incubation using HLMs. Time-dependent inhibition (TDI) kinetics were also measured. RESULTS: It was found that vonoprazan is not a significant direct inhibitor of any CYP isoforms (IC50 ≥ 16 µM), but shows the potential for TDI of CYP2B6, CYP2C19, and CYP3A4/5. This TDI was weaker than the inhibition induced by the corresponding reference inhibitors ticlopidine, esomeprazole, and verapamil, based on the measured potencies (kinact/KI ratio and the R2 value). In a more direct in vitro experiment, vonoprazan levels of up to 10 µM (a 100-fold higher concentration than the plasma Cmax of 75.9 nM after taking 20 mg once daily for 7 days) did not suppress the formation of the active metabolite H4 or other oxidative metabolites of [14C]clopidogrel in a reversible or time-dependent manner. Additionally, an assessment of clinical trials and post-marketing data suggested no evidence of a DDI between vonoprazan and clopidogrel. CONCLUSIONS: The body of evidence shows that the pharmacodynamic DDI reported between vonoprazan and clopidogrel is unlikely to be caused by the inhibition of CYP2B6, CYP2C19, or CYP3A4/5 by vonoprazan.

Application of pharmacometric approaches to evaluate effect of weight and renal function on pharmacokinetics of alogliptin.

AIMS: The aims of the study were to characterize the pharmacokinetics (PK) of alogliptin in healthy and type 2 diabetes mellitus (T2DM) subjects using a population PK approach and to assess the influence of various covariates on alogliptin exposure. METHODS: Plasma concentration data collected from two phase 1 studies and one phase 3 study following administration of alogliptin (12.5-400 mg) were used for the PK model development. One- and two-compartment models were evaluated as base structural PK models. The impact of selected covariates was assessed using stepwise forward selection and backward elimination procedures. The predictability and robustness of the final model was evaluated using visual predictive check and bootstrap analyses. The final model was used to perform simulations and guide appropriate dose adjustments. RESULTS: A two-compartment model with first-order absorption and elimination best described the alogliptin concentration vs. time profiles. Creatinine clearance and weight had a statistically significant effect on the oral clearance (CL/F) of alogliptin. The model predicted a lower CL/F (17%, 35%, 80%) and a higher systemic exposure (56%, 89%, 339%) for subjects with mild, moderate and severe renal impairment, respectively, compared with healthy subjects. Effect of weight on CL/F was not considered clinically relevant. Simulations at different doses of alogliptin support the approved doses of 12.5 mg and 6.25 mg for patients with moderate and severe renal impairment, respectively. CONCLUSIONS: The PK of alogliptin was well characterized by the model. The analysis suggested an alogliptin dose adjustment for subjects with moderate-to-severe renal impairment and no dose adjustments based on weight.

Effects of Peginesatide Injection on QTc Interval in Healthy Adults.

A single-dose, randomized, double-blind, placebo- and positive-controlled, three-period crossover study was conducted to evaluate the effect of peginesatide injection on QT interval in healthy adults. Subjects received single doses of placebo, peginesatide injection 0.1 mg/kg intravenous, or moxifloxacin 400 mg during three treatment periods, separated by 14-day washout intervals. ECG recordings and blood samples for peginesatide and moxifloxacin plasma concentrations were collected prior to dosing and through 22 hours postdose. QT intervals were measured with a high resolution manual on-screen caliper method. The study endpoint was the mean difference between peginesatide and placebo in baseline-adjusted corrected QT interval (ddQTc). The maximum upper bound of the one-sided 95% CI was 2.2 milliseconds at 0.75 hours for Fridericia-corrected ddQTc (ddQTcF) and 2.2 milliseconds at 0.25 hours for individual corrected ddQTcI. The linear relationship between ddQTcF and peginesatide concentrations was essentially flat and not statistically significant [slope = 0.001, P = 0.126, 90% CI: (<-0.0005, 0.002)]. Using this model, the projected ddQTcF effect at the observed mean peak plasma concentration is estimated to be 0.9 milliseconds, 90% CI: (-2.0, 0.3 milliseconds). There were no peginesatide-related effects on heart rate, PR interval, or QRS interval. Thus, there is no anticipated cardiovascular effect of peginesatide injection 0.1 mg/kg in patients.