The purpose of this study is to determine the efficacy and safety of dexlansoprazole compared to placebo in relief of daytime and nighttime heartburn over 4 weeks in Chinese participants with symptomatic non-erosive Gastroesophageal Reflux Disease (GERD).

The drug being tested in this study is called dexlansoprazole. Dexlansoprazole is being tested to treat heartburn in people who have non-erosive gastroesophageal reflux disease (GERD). This study will look at heartburn relief in people who take dexlansoprazole.

The study will enroll approximately 200 participants. Participants will be randomly assigned to one of the two treatment groups with 1:1 ratio -which will remain undisclosed to the participant and study doctor during the study (unless there is an urgent medical need):

• Dexlansoprazole 30 mg
• Placebo (dummy inactive pill) - this is a capsule that looks like the study drug but has no active ingredient.

All participants will be asked to take one capsule at the same time each day throughout the study, and will be asked to record any time they have heartburn symptoms in a diary.

This multi-center trial will be conducted in China. The overall time to participate in this study is up to 7 weeks. Participants will make 4 visits to the clinic, and will be contacted by telephone 5 to 10 days after the last dose of study drug for a follow-up assessment.

Inclusion Criteria:

1. Participants identifying their main symptom as a burning feeling in the mid-epigastric area and/or chest area (that is, heartburn).
2. Must have a history of symptomatic GERD for 6 months or longer prior to Screening with GERD symptoms that were responsive to acid-suppressive therapy.
3. Must have episodes of heartburn for 4 or more days during the 7 days prior to Day -1 as recorded in the eDiary.

Exclusion Criteria:

1. Has a history of cancer (except basal cell carcinoma of the skin), that has not been in remission for at least 5 years prior to Screening.
2. Has a known history of Barrett's esophagus with dysplastic changes or any changes suspicious Barrett's seen during screening endoscopy.
3. Participant developed acute upper gastrointestinal bleeding, gastric ulcer (a mucosal defect with white coating) or duodenal ulcer (a mucosal defect with white coating), within 30 days before the start of the Screening Visit (with the possible inclusion of those with gastric or duodenal erosion). The participant requires chronic use (greater than [>] 12 doses per month) of nonsteroidal anti-inflammatory drugs (NSAIDs) including cyclooxygenase-2 (COX-2) NSAIDs within 30 days prior to the Screening Period and throughout the study.
4. Has comorbidities that could affect the esophagus (eosinophilic esophagitis, esophageal varices, scleroderma, viral or fungal infection, esophageal strictures); a history of radiotherapy or cryotherapy of the esophagus; and a history of corrosive or physiochemical injury (with the possible inclusion in the study of those with Schatzki's ring).
5. Has a history of surgical procedures that may affect the esophagus (example, fundoplication and mechanical dilatation for esophageal strictures) or a history of gastric or duodenal surgery other than endoscopic removal of benign polyps.
6. Has erosive esophagitis (EE) as shown by endoscopy, during the Screening Period.
7. Is known to have acquired immunodeficiency syndrome (AIDS) or hepatitis, including hepatitis virus carriers: (that is, hepatitis B surface antigen HBs-antigen (HBsAg) positive or hepatitis C virus (HCV)-antibody positive).
8. Has current or historical evidence of Zollinger-Ellison syndrome or a history of gastric acid hypersecretion.
9. Is scheduled for surgery that requires hospitalization or requires surgical treatment during his/her participation in the study.
10. Has donated or lost >300 milliliter (mL) blood volume, undergone plasmapheresis, or has had a transfusion of any blood product within 90 days prior to the first dose of study drug.
11. Has a history of alcohol abuse (defined as any illicit drug use), or drug addiction in the 12 months prior to Screening.
12. Participant with positive serology result of Helicobacter pylori (H. pylori) that needs eradication therapy during the study participation period as anticipated by the investigator.

Takeda makes patient-level, de-identified data sets and associated documents available after applicable marketing approvals and commercial availability have been received, an opportunity for the primary publication of the research has been allowed, and other criteria have been met as set forth in Takeda's Data Sharing Policy (see www.TakedaClinicalTrials.com/Approach for details). To obtain access, researchers must submit a legitimate academic research proposal for adjudication by an independent review panel, who will review the scientific merit of the research and the requestor's qualifications and conflict of interest that can result in potential bias. Once approved, qualified researchers who sign a data sharing agreement are provided access to these data in a secure research environment.