Effect of Azithromycin on Oesophageal Hypomotility

Inclusion Criteria: 1. Healthy subjects: 1. Written ICF signed voluntarily before the first trial-related activity. 2. Subjects male and female within age range of 18-70 years old (extremes included) 3. BMI \<35 2. Patients group: 1. Written ICF signed voluntarily before the first trial-related activity. 2. Patients male and female, aged 18-70 3. Been diagnosed with severe oesophageal hypomotility based on Chicago classification 2011 4. Must have moderate or severe reflux symptoms and/ or dysphagia, with at least one of these symptoms of moderate severity or worse, and at a minimum average frequency of three days a week during the two weeks prior to the study date 5. If the subject is a woman of childbearing potential, she 1. must have a negative urine pregnancy test before the start of treatment (minimum β-Human Chorionic Gonadotropin \[HCG\] sensitivity of 25 mIU/ml), and 2. must agree to either use an effective form of birth control (i.e., stabilized on oral contraceptives for at least 1 month or using implanted, transdermal or injected contraceptive hormones, an intra-uterine device, or continuous abstinence from heterosexual sexual contact), or a combination of a barrier method and a spermicidal agent (i.e., cervical cap and spermicidal agent, condom and spermicidal agent, or diaphragm and spermicidal agent), Exclusion Criteria: * Healthy subjects: 1. Any incidental abnormal oesophageal motility finding 2. History of gastrointestinal symptoms, gastrointestinal tract surgery or other recent abdominal operation within last 3 months. 3. Major psychiatric, neurological, respiratory, liver, haemorrhagic and cardiac disorders, malignancies 4. Pregnancy and no wheat allergy * Patients: 1. Subjects with a documented history of long segment (\>3 cm) Barrett's oesophagus. 2. Subjects with documented or suspected large (\> 3 cm) hiatus hernia. 3. Subjects with fundoplication, endoscopic anti-reflux procedure or major prior GI surgery. 4. Subjects with structural abnormalities of oesophagus (ie. Rings and webs, scleroderma) 5. Severe oesophageal motility disorders other than oesophageal hypomotility (e.g., achalasia, nutcracker oesophagus). 6. Subjects who suffer from frequent vomiting (\>1/week) 7. Current diagnosis of co-existing psychiatric disease (including alcohol or drug abuse); controlled depression and anxiety are allowed, when treated with at most 8. Allergy to prokinetic medicine (AZI), gluten or egg, allergy to latex (reflux monitoring catheter has cross reaction with latex) 9. Patients with concomitant prohibited medications, unless willing or able to withdraw from these medications 10. Use of prohibited co-medication less than 7 days before the start of the study 11. Any condition that, in the opinion of the Investigator, would complicate or compromise the trial (e.g., human immunodeficiency virus \[HIV\] infection, gastroduodenal ulcer) or the well-being of the subject, or evidence of any clinically relevant pathology that could interfere with trial results or put subject safety at risk. 12. Participation in an investigational drug trial in 30 days prior to enrolment. 13. Pregnant or breast-feeding subjects.