A Study to Evaluate the Efficacy and Safety of Vonoprazan Compared to Placebo in Participants With Symptomatic Non-Erosive Gastroesophageal Reflux Disease
CompletedPhase 2Results postedLast updated 4 January 2023
What this trial tests
Phase 2 trial testing Vonoprazan in Non-Erosive Gastro-Esophageal Reflux Disease in 458 participants. Completed in 17 January 2022.
18 and older, any sex, with Non-Erosive Gastro-Esophageal Reflux Disease or Heartburn. Patients with the condition only — healthy volunteers not accepted.
Results — posted to ClinicalTrials.gov
Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.
Percentage of Evaluable Heartburn Episodes Completely Relieved Within 3 Hours and With No Further Heartburn Reported for 24 Hours After Taking Study DrugPrimary· On-Demand Treatment Period: Day 1 to Day 42
An evaluable heartburn episode was an episode for which study drug was taken and for which the participant completed at least one entry in the heartburn episode diary.
For a heartburn episode to be considered completely relieved, a participant must not have taken rescue antacid within 3 hours of taking study drug. For sustained relief, complete relief must have been accompanied by 24 hours without another heartburn episode after taking study drug.
Group
Value
95% CI
Vonoprazan 10 mg: On-Demand Treatment Period
56.0
Vonoprazan 20 mg: On-Demand Treatment Period
60.6
Vonoprazan 40 mg: On-Demand Treatment Period
70.0
Placebo: On-Demand Treatment Period
27.3
Percentage of Evaluable Heartburn Episodes Completely Relieved Within 3 Hours After Taking Study DrugSecondary· On-Demand Treatment Period: Day 1 to Day 42
An evaluable heartburn episode was an episode for which study drug was taken and for which the participant completed at least one entry in the heartburn episode diary.
For a heartburn episode to be considered completely relieved, a participant must not have taken rescue antacid within 3 hours of taking study drug.
Group
Value
95% CI
Vonoprazan 10 mg: On-Demand Treatment Period
72.1
Vonoprazan 20 mg: On-Demand Treatment Period
65.7
Vonoprazan 40 mg: On-Demand Treatment Period
79.6
Placebo: On-Demand Treatment Period
41.9
Percentage of Evaluable Heartburn Episodes for Each Participant That Are Completely Relieved Within 3 Hours and With No Further Heartburn Reported for 24 Hours After Taking Study DrugSecondary· On-Demand Treatment Period: Day 1 to Day 42
An evaluable heartburn episode was an episode for which study drug was taken and for which the participant completed at least one entry in the heartburn episode diary.
For a heartburn episode to be considered completely relieved, a participant must not have taken rescue antacid within 3 hours of taking study drug. For sustained relief, complete relief must have been accompanied by 24 hours without another heartburn episode after taking study drug.
Group
Value
95% CI
Vonoprazan 10 mg: On-Demand Treatment Period
60.08
± 38.452
Vonoprazan 20 mg: On-Demand Treatment Period
60.78
± 37.458
Vonoprazan 40 mg: On-Demand Treatment Period
71.99
± 28.894
Placebo: On-Demand Treatment Period
47.77
± 40.998
Mean Number of Tablets of Rescue Antacid Taken Per Day Over the On-Demand Treatment PeriodSecondary· On-Demand Treatment Period: Day 1 to Day 42
Group
Value
95% CI
Vonoprazan 10 mg: On-Demand Treatment Period
0.1
± 0.21
Vonoprazan 20 mg: On-Demand Treatment Period
0.2
± 0.29
Vonoprazan 40 mg: On-Demand Treatment Period
0.1
± 0.26
Placebo: On-Demand Treatment Period
0.5
± 0.87
Percentage of Participants With Complete Relief of Heartburn Within 3 Hours After the First Episode and With No Further Heartburn Reported for 24 Hours After Taking Study DrugSecondary· On-Demand Treatment Period: Day 1 to Day 42
An evaluable heartburn episode was an episode for which study drug was taken and for which the participant completed at least one entry in the heartburn episode diary.
For a heartburn episode to be considered completely relieved, a participant must not have taken rescue antacid within 3 hours of taking study drug. For sustained relief, complete relief must have been accompanied by 24 hours without another heartburn episode after taking study drug.
Group
Value
95% CI
Vonoprazan 10 mg: On-Demand Treatment Period
56.5
Vonoprazan 20 mg: On-Demand Treatment Period
61.9
Vonoprazan 40 mg: On-Demand Treatment Period
62.8
Placebo: On-Demand Treatment Period
60.5
Percentage of Days Study Drug Was Taken Over the On-Demand Treatment PeriodSecondary· On-Demand Treatment Period: Day 1 to Day 42
Group
Value
95% CI
Vonoprazan 10 mg: On-Demand Treatment Period
21.93
± 19.241
Vonoprazan 20 mg: On-Demand Treatment Period
20.75
± 16.950
Vonoprazan 40 mg: On-Demand Treatment Period
21.01
± 17.302
Placebo: On-Demand Treatment Period
22.15
± 23.266
Percentage of 24-Hour Heartburn-Free Days Over the On-Demand Treatment PeriodSecondary· On-Demand Treatment Period: Day 1 to Day 42
A 24-hour heartburn-free day was defined as a day having no heartburn among all diary entries for that day. The percentage of 24-hour heartburn-free days was calculated using all days with at least 1 evening or morning diary entry during the treatment period of this phase.
Group
Value
95% CI
Vonoprazan 10 mg: On-Demand Treatment Period
74.95
± 21.410
Vonoprazan 20 mg: On-Demand Treatment Period
73.57
± 21.465
Vonoprazan 40 mg: On-Demand Treatment Period
74.01
± 22.277
Placebo: On-Demand Treatment Period
71.22
± 28.867
Adverse events — posted to ClinicalTrials.gov
Time frame: Run-In Period: Day 1 to Day 28; On-Demand Treatment: Day 1 to Day 49.
Reporting threshold: 2%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
The primary objectives of this study are to assess the efficacy of vonoprazan (10 mg, 20 mg, and 40 mg On-Demand) compared to placebo (On-Demand) in relief of episodic heartburn over 6 weeks in participants with symptomatic non-erosive gastroesophageal reflux disease (NERD), and to assess the safety of vonoprazan (10 mg, 20 mg, and 40 mg On-Demand) compared to placebo (On-Demand) in participants with symptomatic NERD.
Publications & conference data
1 peer-reviewed publication reference this trial (live from Europe PMC):
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NCT06955520 — Vonaprazan Versus Esomeprazole for Healing of LA Grade B or Higher Esophagitis After POEM
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· recruiting
NCT07068607 — Efficacy Comparison of Vonoprazan Combined With Different Antibiotics in Dual Therapy for Helicobacter Pylori Eradicatio
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NCT07242456 — Head-to-head Study of Tegoprazan 50 mg BID Plus Amoxicillin 1 g TID vs. Vonoprazan 20 mg BID Plus Amoxicillin 1 g TID fo
· Phase 2, PHASE3
· recruiting
NCT06811207 — Comparison of the Efficacies of Two Novel Dose Dual Therapies in the First-line Helicobacter Pylori Eradication
· Phase 3
· unknown
Other recruiting trials for Non-Erosive Gastro-Esophageal Reflux Disease
Currently open trials in the same condition.
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Trials by the same sponsor.
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Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Phathom Pharmaceuticals, Inc.
Last refreshed: 4 January 2023
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT04799158.