Velusetrag for the Treatment of Chronic Intestinal Pseudo-Obstruction (CIPO).

Inclusion Criteria: * Subjects with history of chronic idiopathic intestinal pseudo-obstruction or CIPO secondary to neurodegenerative or demyelinating disease. * Subjects with estimated oral caloric intake of at least 30% of the daily age- and sex-recommended caloric intake. * Subjects with at least 2 out of 4 CIPO gastrointestinal symptoms each of the 2 with a score ≥3 (on a 0 to 4 scale) at Day -1 * Subjects accepting to provide and legally capable of providing free and informed consent to all procedures included in the protocol. * All sexually active male participants who are partner of women of childbearing potential must use condom during intercourse until the 90th day after the end of the entire study. * Female participants are eligible if they are: i) of non-childbearing potential or ii) of childbearing potential with a negative pregnancy test result at screening and randomization AND agreeing to use a highly effective method of contraception (i.e., with failure rate of less than 1% per year) until the end of the entire study. Exclusion Criteria: * Subjects with primary CIPO or CIPO secondary to other known endocrine/metabolic, autoimmune diseases and neurologic conditions other than neurodegenerative or demyelinating diseases. * Subjects with conditions characterized by mechanical intestinal obstruction. * Nasogastric tube, gastrostomy tube, or jejunostomy feeding tube in place at randomization or planned throughout the duration of the study, or artificial food need scale stage 3. * Presence of untreated clinically relevant thyroid dysfunction or known thyroid dysfunction not well controlled by treatment deemed clinically significant by the Investigator. * Subjects with history of diabetes at screening. * Clinically significant ECG abnormalities at screening and randomization. * Screening ECG with a QTcF \>450 msec in males or \>470 msec in females or family history of sudden cardiac death. * Subjects requiring a low galactose diet. * Hypersensitivity or documented intolerance to lactulose, lactose or any excipient of the lactulose preparation to be used for L-BT. * History of sensitivity to velusetrag, or any of the velusetrag or placebo excipients. * Use of scopolamine or erythromycin within 2 weeks prior to screening and/or planned throughout the duration of the study. * Use of 5-HT4 receptor agonists within 5 days prior to randomization and/or planned throughout the duration of the study * Use of opioids within 8 weeks from screening and/or planned throughout the duration of the study. * Received strong cytochrome P450-isozyme 3A4 (CYP3A4) inhibitors within 2 weeks prior to screening and/or planned throughout the duration of the study. * Received strong P-glycoprotein (P-gp) transporter inhibitors within 2 weeks prior to Screening and/or planned throughout the duration of the study. * Received strong breast cancer resistance protein transporter inhibitors within 2 weeks prior to screening and/or planned throughout the duration of the study. * Current swab-positive or suspected (under investigation) COVID-19 infection. * Cancer (excluding non-melanoma skin cancer) and/or need of any anti-cancer treatment (also including radiotherapy) within the last 5 years. * Severe kidney impairment. * Aspartate aminotransferase (AST) or alanine transaminase (ALT) levels \>2.5 times the upper limit of normal (ULN); bilirubin (unless deemed to be due to Gilbert's Syndrome) or alkaline phosphatase (ALP) \>1.5 times ULN. * Severe hepatic impairment defined as Child-Pugh C. * History of any of the following cardiac disorders: i) torsade de pointes, ventricular tachycardia, ventricular fibrillation; ii) previous myocardial infarction, unstable angina pectoris, acute coronary syndrome, coronary artery or cerebral revascularization procedure or stroke within the previous 18 months; iii) angina pectoris class 2-4 during the last 12 months prior to screening; iv) congestive heart failure NYHA class III-IV during the last 18 months prior to screening. * History of any alcohol or drug abuse or dependence within the last year (Investigator's judgement). * Any current significant health condition that in the Investigator's judgement may: i) jeopardize the patient's safe participation in the trial or ii) make unlikely the patient's completion of the study or iii) make unlikely the patient's compliance with the study procedures. * Pregnant or breastfeeding woman. * Use of any experimental drug within 12 weeks prior to screening