Patient description: The patient is a 57-year-old man with abdominal pain and vomiting. The pain started gradually about 20 hours ago in the epigastric and periumbilical regions, radiating to his back. He drinks around 60 units of alcohol per week and smokes 22 cigarettes per day. He is healthy with no history of allergies or using any medications. His family history is positive for type 2 diabetes (his father and sister). He lives alone and has no children. The abdomen is tender and soft. His bowel sounds are normal. His heart rate is 115/min and blood pressure 110/75 mmHg. The lab results are remarkable for leukocytosis (19.5), urea of 8.5, high CRP (145), high amylase (1200) and Glc level of 15. Cross-sectional imaging was negative for obstructive pancreatitis.

Clinical trial eligibility criteria: eligible ages (years): 18.0-75.0,  Renal Disease, End Stage Healthy Subjects 1. Age 18 to 75 years of age at time of signing ICF. 2. Body mass index (BMI) between 18 and 38 kg/m2. 3. Must be willing and able to communicate and participate in the whole study. 4. Must provide written informed consent. 5. Must agree to use an adequate method of contraception 6. Healthy as defined by The absence of clinically significant illness and surgery within 4 weeks prior to dosing. Subjects vomiting within 24 hours pre-dose will be carefully evaluated for upcoming illness/disease. pre-dosing is at the discretion of the Principal Investigator The absence of clinically significant history of neurological, endocrine, cardiovascular, pulmonary, hematological, immunologic, psychiatric, gastrointestinal, renal, hepatic (including cholecystectomy), and metabolic disease The absence of clinically significant history of lactic acidosis and severe hepatomegaly with steatosis The absence of history of suicidal tendency, disposition to seizures, state of confusion, or clinically relevant psychiatric diseases. 7. Normal renal function, i.e., eGFR or creatinine clearance ≥ 90 mL/min/1.73 m2 as calculated using the MDRD4 or Cockcroft-Gault equation; at the Principal Investigator's discretion, 24 hour creatinine clearance may be conducted to determine renal function. 8. Matched to subjects with severe renal impairment for gender, age (± 10 years), and BMI (± 15%) to the extent possible. Renal Impaired Subjects 1. Age 18 to 75 years of age at time of signing ICF. 2. Body mass index (BMI) between 18 and 38 kg/m2. 3. Must be willing and able to communicate and participate in the whole study. 4. Must provide written informed consent. 5. Must agree to use an adequate method of contraception 6. A diagnosis of renal impairment that has been stable, without significant change in overall disease status in the 3 months prior to screening as determined by the Principal Investigator, with no requirement for dialysis, and an eGFR at screening < 30 mL/min/1.73 m2 calculated using the MDRD4 equation  Healthy Subjects 1. Subjects who have received any IMP in a clinical research study within the 30 days prior to IMP administration on this study. 2. Subjects who are study site, CRO or sponsor employees, or immediate family members of a study site, CRO or sponsor employee. 3. Subjects who have previously been enrolled in this study. 4. Women who are pregnant or breastfeeding. 5. Subjects who have received amisulpride for any indication within the 30 days prior to dosing. 6. Allergy to amisulpride or any of the excipients of amisulpride. 7. History of any drug or alcohol abuse in the 2 years prior to screening. 8. Regular alcohol consumption >21 units per week in the 6 months prior to screening. 9. Subjects who do not have suitable veins for multiple venepunctures/cannulation as assessed by the investigator at screening. 10. History of epilepsy in the 5years prior toscreening. 11. History of clinically significant syncope. 12. Family history of sudden death. 13. Family history of premature cardiovascular death. 14. Clinically significant history or family history of congenital long QT syndrome (e.g. Romano-Ward syndrome, Jervell and Lange-Nielson syndrome) or Brugada's syndrome. 15. History of clinically significant arrhythmias or ischaemic heart disease (especially ventricular arrhythmias, atrial fibrillation (AF), recent conversion from AF or coronary spasm). 16. Conditions predisposing the volunteer to electrolyte imbalances (e.g. altered nutritional states, chronic vomiting, anorexia nervosa, bulimia nervosa). 17. Clinically significant abnormal biochemistry,haematology or urinalysis at screening as judged by the investigator 18. Positive drugs of abuse test result 19. Positive hepatitis B surface antigen (HBsAg), hepatitis C virus antibody (HCV Ab) or human immunodeficiency virus (HIV) results at screening. 20. Donation of plasma within 7 days prior to dosing. Donation or loss of blood (excluding volume drawn at screening or menses) of 50 mL to 499 mL of blood within 30 days, or more than 499 mL within 56 days prior to the dosing. 21. Subjects who are taking, or have taken, any prescribed or over-the-counter drug (other than 2,000 mg per day acetaminophen) or herbal remedies in the 14 days before IMP administration 22. Administration of a biological product in the context of a clinical research study within 90 days prior to dosing, or concomitant participation in an investigational study involving no drug or device administration. 23. Failure to satisfy the investigator of fitness to participate for any other reason Renal Impaired Subjects 1. Subjects who have received any IMP in a clinical research study within the 30 days prior to IMP administration on this study. 2. Subjects who are study site, CRO or sponsor employees, or immediate family members of a study site, CRO or sponsor employee. 3. Subjects who have previously been enrolled in this study. 4. Women who are pregnant or breastfeeding. 5. Subjects who have received amisulpride for any indication within the 30 days prior to dosing. 6. Allergy to amisulpride or any of the excipients of amisulpride. 7. History of any drug or alcohol abuse in the 2 years prior to screening. 8. Regular alcohol consumption >21 units per week in the 6 months prior to screening. 9. Subjects who do not have suitable veins for multiple venepunctures/cannulation as assessed by the investigator at screening. 10. History of epilepsy in the 5years prior to screening. 11. History of clinically significant syncope. 12. Family history of sudden death. 13. Family history of premature cardiovascular death. 14. Clinically significant history or family history of congenital long QT syndrome (e.g. Romano-Ward syndrome, Jervell and Lange-Nielson syndrome) or Brugada's syndrome. 15. History of clinically significant arrhythmias or unstable ischaemic heart disease (especially ventricular arrhythmias, atrial fibrillation (AF), recent conversion from AF or coronary spasm). 16. Positive drugs of abuse test result, unless caused by a documented prescription drug. 17. Positive hepatitis B surface antigen (HBsAg), hepatitis C virus antibody (HCV Ab) or human immunodeficiency virus (HIV) results at screening. 18. Donation of plasma within 7 days prior to dosing. Donation or loss of blood (excluding volume drawn at screening or menses) of 50 mL to 499 mL of blood within 30 days, or more than 499 mL within 56 days prior to the dosing. 19. Administration of a biological product in the context of a clinical research study within 90 days prior to dosing, or concomitant participation in an investigational study involving no drug or device administration. 20. Failure to satisfy the investigator of fitness to participate for any other reason