Vonoprazan, a novel potassium-competitive acid blocker, as a component of first-line and second-line triple therapy for Helicobacter pylori eradication: a phase III, randomised, double-blind study.

OBJECTIVE: The objective of this study was to assess the efficacy, safety and tolerability of vonoprazan, a novel potassium-competitive acid blocker, as a component of Helicobacter pylori eradication therapy. DESIGN: A randomised, double-blind, multicentre, parallel-group study was conducted to verify the non-inferiority of vonoprazan 20 mg to lansoprazole 30 mg as part of first-line triple therapy (with amoxicillin 750 mg and clarithromycin 200 or 400 mg) in H pylori-positive patients with gastric or duodenal ulcer history. The first 50 patients failing first-line therapy with good compliance also received second-line vonoprazan-based triple therapy (with amoxicillin 750 mg and metronidazole 250 mg) as an open-label treatment. RESULTS: Of the 650 subjects randomly allocated to either first-line triple therapy, 641 subjects completed first-line therapy and 50 subjects completed second-line therapy. The first-line eradication rate (primary end point) was 92.6% (95% CI 89.2% to 95.2%) with vonoprazan versus 75.9% (95% CI 70.9% to 80.5%) with lansoprazole, with the difference being 16.7% (95% CI 11.2% to 22.1%) in favour of vonoprazan, thus confirming the non-inferiority of vonoprazan (p<0.0001). The second-line eradication rate (secondary end point) was also high (98.0%; 95% CI 89.4% to 99.9%) in those who received second-line therapy (n=50). Both first-line triple therapies were well tolerated with no notable differences. Second-line triple therapy was also well tolerated. CONCLUSION: Vonoprazan is effective as part of first-line triple therapy and as part of second-line triple therapy in H pylori-positive patients with a history of gastric or duodenal ulcer. TRIAL REGISTRATION NUMBER: NCT01505127.

Evaluation of the Efficacy and Safety of Vonoprazan in Patients with Nonerosive Gastroesophageal Reflux Disease: A Phase III, Randomized, Double-Blind, Placebo-Controlled, Multicenter Study.

BACKGROUND: For many patients, current treatments do not adequately resolve heartburn in nonerosive reflux disease (NERD). OBJECTIVE: To compare vonoprazan and placebo with respect to the frequency and severity of heartburn in patients with NERD. METHODS: This Phase III, double-blind, placebo-controlled, parallel-group, multicenter study included patients in Japan aged ≥20 years with Grade N or M NERD and recurrent acid reflux symptoms. Patients were blinded and randomized 1:1:1 to receive placebo or vonoprazan 10 mg or 20 mg. The primary efficacy outcome was the proportion of days without heartburn measured by patient scores during the 4-week treatment period. RESULTS: Eight hundred twenty-seven patients were randomized (placebo: n = 278, vonoprazan 10 mg: n = 278, and vonoprazan 20 mg: n = 271). Median proportion of days without heartburn was 7.4% (placebo), 10.3% (vonoprazan 10 mg), and 12.0% (vonoprazan 20 mg). Proportion of days without heartburn was not statistically significant between the vonoprazan and placebo groups (P = 0.2310 [10 mg] and P = 0.0504 [20 mg]). Mean severity of heartburn was significantly higher with placebo (median score = 1.070) than with vonoprazan 10 mg (median score = 0.990; P = 0.0440) and 20 mg (median score = 0.960; P = 0.0139). Patients whose symptoms improved at Week 2 experienced significantly increased proportion of days without heartburn and reduced mean severity of heartburn at Week 4 with vonoprazan compared with placebo (proportion of days without heartburn: P = 0.0004 [10 mg] and P = 0.0001 [20 mg] and mean severity: P < 0.0001 [10 mg] and P < 0.0001 [20 mg]). A significant difference in median proportion of days without heartburn was observed for vonoprazan 20 mg compared with placebo in patients with Grade M NERD. Incidence of treatment-emergent adverse events was 32.7% (placebo), 27.7% (vonoprazan 10 mg), and 28.0% (vonoprazan 20 mg). CONCLUSIONS: Vonoprazan at doses of 10 mg and 20 mg are not superior to placebo with respect to proportion of days without heartburn, whereas the mean severity of heartburn is lower with vonoprazan compared with placebo in patients with NERD. ClinicalTrials.gov identifier: NCT01474369.

A randomized, double-blind study to evaluate the acid-inhibitory effect of vonoprazan (20 mg and 40 mg) in patients with proton-pump inhibitor-resistant erosive esophagitis.

BACKGROUND: Standard treatment for patients with erosive esophagitis (EE) is proton-pump inhibitors (PPIs), but some patients are resistant to PPIs. We aimed to evaluate the acid-inhibitory effects and efficacy of a novel potassium-competitive acid blocker (vonoprazan) in patients with PPI-resistant EE. METHODS: This randomized, double-blind, multicenter study of vonoprazan evaluated gastric and esophageal pH over a 24-hour period as the primary endpoint and EE healing rate as the secondary endpoint. Following a 7 to 14-day run-in period (lansoprazole 30 mg treatment), patients with endoscopically confirmed PPI-resistant EE received vonoprazan 20 mg or 40 mg for 8 weeks. RESULTS: Patients were randomized to receive vonoprazan 20 mg (n = 9) or 40 mg (n = 10). Over a 24-hour period; both groups showed a significant increase from baseline in the percentage of time gastric pH ≥ 4, referred to as pH 4 holding time ratio (HTR): an increase from 73.21% to 96.46% in the 20 mg group, and from 69.97% to 100.00% in the 40 mg group. Increases from baseline in esophageal pH 4 HTRs were not significant. The 40 mg group showed greater increases in gastric and esophageal pH 4 HTRs compared with the 20 mg group, but differences between groups were not significant. After 8 weeks' treatment, the healing rate in subjects with baseline EE grades A-D was 60.0% (3/5 patients) in the 20 mg group and 71.4% (5/7 patients) in the 40 mg group. Vonoprazan was generally well tolerated. One patient (40 mg group) experienced four treatment-emergent adverse events (TEAEs) (unrelated to study drug), leading to study discontinuation. CONCLUSIONS: Vonoprazan 20 mg and 40 mg effectively inhibited gastric acid secretion over a 24-hour period with significantly increased gastric pH 4 HTR, and resulted in an EE healing rate > 60.0% in this study. Vonoprazan treatment may be valuable for patients with PPI-resistant EE.

Pharmacokinetic Drug-Drug Interactions Between Vonoprazan and Low-Dose Aspirin or Nonsteroidal Anti-inflammatory Drugs: A Phase 2, Open-Label, Study in Healthy Japanese Men.

BACKGROUND: Gastroprotective agents are recommended for patients receiving low-dose aspirin (LDA) or nonsteroidal anti-inflammatory drugs (NSAIDs). Vonoprazan is a potassium-competitive acid blocker recently approved for the prevention of peptic ulcer recurrence in patients receiving LDA or NSAIDs. METHODS: This phase 2, open-label, single-center study in healthy Japanese males evaluated drug-drug interactions between vonoprazan 40 mg and LDA (100 mg) or NSAIDs [loxoprofen sodium (60 mg), diclofenac sodium (25 mg), or meloxicam (10 mg)] and vice versa. Subjects were allocated to one of eight cohorts and received their orally administered treatment regimen (to assess the effect of vonoprazan vs. NSAID or LDA, or vice versa) once daily. Endpoints were the pharmacokinetics of plasma concentrations of the study drugs alone and in combination (primary), safety (secondary), and vonoprazan effects on aspirin-mediated inhibition of platelet-aggregation. RESULTS: Of 109 subjects screened, 64 were assigned to one of eight cohorts (n = 8 per cohort) and received treatment, one subject discontinued due to a treatment-emergent adverse event (TEAE), and 63 completed the study. There were few differences in the pharmacokinetics of vonoprazan when administered with LDA or NSAIDs, and few differences in the pharmacokinetics of LDA or NSAIDs when administered with vonoprazan. The differences were small and not clinically meaningful. Inhibition of arachidonic-induced platelet aggregation by LDA was not influenced by vonoprazan. Six patients experienced a TEAE, all were mild and were deemed unrelated to study drugs. One subject withdrew due to infection (tonsillitis). CONCLUSIONS: No clinically meaningful drug-drug interactions were observed and vonoprazan was well tolerated when administered with LDA or NSAIDs. STUDY REGISTRATION: JapicCTI-153100.

Pharmacokinetics and Safety of Triple Therapy with Vonoprazan, Amoxicillin, and Clarithromycin or Metronidazole: A Phase 1, Open-Label, Randomized, Crossover Study.

INTRODUCTION: Vonoprazan (TAK-438) is a novel potassium-competitive acid blocker that inhibits gastric H(+), K(+)-ATPase. The objectives of this study were to evaluate the influence of triple therapy with vonoprazan-amoxicillin-clarithromycin or vonoprazan-amoxicillin-metronidazole on the pharmacokinetics of each component of the triple therapies (primary) and to evaluate the safety and tolerability of vonoprazan-based triple therapies (secondary) in healthy adults. METHODS: In this single-center, phase 1, open-label, randomized, four-way crossover study, Helicobacter pylori-negative, healthy Japanese male subjects were randomly assigned to 1 of 4 treatment sequences in two cohorts (12 subjects per cohort). Each treatment sequence comprised four treatment periods separated by a washout period of 7 or 14 days. Pharmacokinetic parameters for vonoprazan, amoxicillin, clarithromycin and metronidazole in single therapy or triple therapies were assessed. All adverse events were recorded. RESULTS: Compared with single therapy, triple therapy with vonoprazan-amoxicillin-clarithromycin increased the area under the plasma concentration-time curve from time 0-12 h (AUC0-12) and maximum plasma concentration (C max) of plasma vonoprazan free base by 1.846- and 1.868-fold, respectively, and increased the AUC0-12 and C max of plasma clarithromycin by 1.450- and 1.635-fold, respectively. Triple therapy with vonoprazan-amoxicillin-metronidazole had no influence on the pharmacokinetics of vonoprazan or metronidazole. The pharmacokinetics of amoxicillin was not influenced by vonoprazan-based triple therapies. Seven adverse events were reported. Two subjects discontinued because of an adverse event (rash, liver function test abnormal); both events were considered to be study drug-related. CONCLUSION: In healthy Japanese male subjects, triple therapy with vonoprazan-amoxicillin-clarithromycin increased vonoprazan and clarithromycin exposure. The safety and tolerability profile of triple therapy with vonoprazan-amoxicillin-clarithromycin or vonoprazan-amoxicillin-metronidazole was favorable in this population. FUNDING: Takeda Pharmaceutical Company Ltd. TRIAL REGISTRATION: JapicCTI-153102.