Compound Sodium Alginate Double Action Chewable Tablets 4-hour Esophageal PH Study in GERD Patients

Inclusion Criteria:

• meets the diagnostic criteria for GERD with a GERD history of frequent episodes ofGERD-related symptoms during the last 2 months prior to study screening. The patientmust also meet the following criteria:

1. The only or main symptom is heartburn (burning feeling back of breast bone)and/or acid reflux. Symptoms persists or have occurred repeatedly for more than 2 months;

2. As assessed by the Investigator at screening by questioning of the patient, thefrequency of occurrence of heartburn is ≥ 3 days/week and the score of severityof heartburn in general is ≥ moderate within 3 weeks before screening

Exclusion Criteria:

• Patients who have a history of drug, solvent or alcohol abuse (weekly alcohol intake ≥ 140g).

• Patients who have suffered cardiac chest pain within the last year.

• Patients who have suffered a recent, significant unexplained weight loss of morethan 6 kg in the last 6 months.

• Female patients of childbearing potential who, for the duration of the study, areeither unwilling or unable to take adequate contraceptive precautions or areunwilling to be sexually abstinent.

• Pregnancy or lactating mother.

• Patients with a history and/or symptom profile suggestive of the following: anyother gastrointestinal (GI) disease, erosive GERD (Los Angeles [LA] classificationgrades C-D), Barrett's esophagus, acute peptic ulcer and/or ulcer complications,Zollinger-Ellison syndrome, gastric carcinoma, pyloric stenosis, oesophageal orgastric surgery, intestinal obstruction, current pernicious anaemia, indication forH-pylori eradication therapy, known gastrointestinal bleeding (hematochezia orhematemesis) within the last 3 months, and severe diseases of other major bodysystems.

• Patients who are observed at screening to have a hiatus hernia with a diameter whichexceeds 3cm.

• Patients who have taken anti-cholinesterase drugs, traditional Chinese medicines fortreating gastrointestinal disease, ulcerlmin or misoprostol preparations within 7days prior to screening or throughout the study.

• Patients who have taken PPIs during the 10 days prior to screening, prokinetics orH2 antagonists during the 5 days prior to screening or systemicglucocorticosteroids, non-steroidal anti-inflammatory drugs (except for low doseaspirin which can be given for cardioprotection) on more than 3 consecutive days orPPI-based triple or quadruple therapy for eradication of H-pylori during the last 28days.

• Patients taking or requiring to take macrolide antibiotics, such as erythromycin,azithromycin, from the day before screening.

• Patients with difficulty in swallowing.

• Patients with known hypophosphataemia, phenylketonuria or hypercalcaemia.

• Patients with severe constipation, or history of intestinal obstruction.

• In the opinion of the Investigator, patients with damaged heart or kidney functionand patients who require a low sodium diet.