The study is a prospective, adaptive, multicenter, randomized, double-blind, Sham-controlled study, to evaluate the efficacy and safety of the Vibrant Capsule in relieving constipation in subjects with functional constipation.

Two arms will be assessed:

• Vibrant Capsule administered 5 times per week
• Sham Capsule administered 5 times per week

The study is a prospective, adaptive, multicenter, randomized, double-blind, Sham-controlled study, to evaluate the efficacy and safety of the Vibrant Capsule in relieving constipation in subjects with functional constipation.

Two arms will be assessed:

• Vibrant Capsule administered 5 times per week
• Sham Capsule administered 5 times per week

Subjects will follow a 2 weeks baseline period and then take the Vibrant Capsule for a treatment period of 8 weeks.

Data reporting will be done on an electronic Case Report Form (eCRF) and an eDiary.

Subjects will be asked to refrain from taking any medication or supplement to relieve their constipation, during the entire study period.

After the 14 days of run-in period, the subjects will return and eligibility will be re-assessed. Subjects will be trained on how to use the base unit and will swallow the first capsule on site the day of baseline visit. They will activate and ingest the rest of the capsules at home by themselves, using the base unit.

Subjects will be instructed to complete a simple subject eDiary each day throughout the duration of the study. A final visit will take place at the end of the 8 week treatment period.

Subjects will receive phone calls at least once a week and subject compliance will be monitored during the 8 weeks of the study.

Inclusion Criteria:

1. Subjects aged 22 years and older
2. Subjects with Chronic Idiopathic Constipation (CIC) according to Rome III criteria and who have not experienced relief of their symptoms from available therapies
3. Subjects with an average of <3 Spontaneous Bowel Movements (SBM) per week and ≥1 SBM per week
4. Normal colonoscopy performed within 10 years prior to study participation, unless the subjects are <50 years old and without alarm signs and/or symptoms
5. Subject signed the Informed Consent Form (ICF)
6. Female subjects must have a negative pregnancy test

Exclusion Criteria:

1. History of complicated/obstructive diverticular disease

2. History of intestinal or colonic obstruction, or suspected intestinal obstruction.

3. History of significant gastrointestinal disorder, including any form of inflammatory bowel disease or gastrointestinal malignancy (celiac disease is accepted if the subject has been treated and is in remission)

4. History of gastroparesis

5. Use of any of the following medications:

   • Medications that may affect intestinal motility, prokinetics, anti-depressants, anti-Parkinsonian medications, opiates, opioids, calcium-channel blockers, aluminum/magnesium hydroxide
   • With the exception of antidepressants, thyroid or hormonal replacement therapy, when the subject has been on a stable dose for at least 3 months prior to enrollment.

6. Clinical evidence of significant respiratory, cardiovascular, renal, hepatic, biliary, endocrine, psychiatric or neurologic disease.

7. Presence of cardiac pacemaker or gastric electrical stimulator.

8. History of, or current eating disorders, such as anorexia, bulimia, or compulsory overeating.

9. Diagnosis of mega-rectum or colon, congenital anorectal malformation, clinically significant rectocele, history of intestinal resection (with an exception for appendectomy, cholecystectomy and inguinal hernia repair), history of bariatric surgery or evidence of any structural abnormality of the gastrointestinal tract that might affect transit

10. History of Zenker's diverticulum, dysphagia, Barrett's esophagus, esophageal stricture or achalasia

11. Chronic use of non-steroidal anti-inflammatory drugs (NSAIDs)

12. Subjects with pelvic floor dysfunction/defecatory disorder

13. Participation in another clinical study within one month prior to screening.

14. Women who are pregnant or lactating

Data from this study will be presented in future Vibrantgastro publications.

8 weeks