Fasting Bioequivalence Study of 2 Metformin 500 mg Prolonged Release Tablets in 44 Healthy Male and Female Volunteers

Inclusion Criteria: * Healthy males and non-pregnant and no breast-feeding females (must have a negative pregnansy test result prior to dosing). Caucasian race. * Non-smoker or past-smoker (who has stopped smoking at least 6 months before the first dosing). * Body Mass Index (BMI) 18.5 to 30.0 kg/m2, inclusive and body weight between 50 kg and 100 kg (on the day of screening). * Subject was available for the whole study and has provided his/her written informed consent. * Subjects in good health, as determined by screening medical history, physical examination, vital signs assessments (pulse rate, systolic and diastolic blood pressure, and body temperature) and 12-lead ECG. Minor deviations outside the reference ranges were acceptable, if deemed not clinically significant by the Investigator. * All laboratory screening results within the normal range. Minor deviations outside the reference ranges were acceptable, if deemed not clinically significant by the Clinical Investigator. * Acceptance of use of contraceptive measures during the whole study by both female and male subjects. Exclusion Criteria: * Known cardiovascular disease, history of hypotension. * Factors in the subject's history that may predispose to ketoacidosis (including pancreatic insulin deficiency, history of pancreatitis, caloric restriction disorders, restricted food intake, alcohol abuse). * Gastrointestinal, renal or hepatic diseases and/or pathological findings present or in history, which might interfere with the drug pharmacokinetics. * Glucose level out of the limit 3.3 mmol/L - 5.5 mmol/Lat screening, as determined by screening clinical laboratory evaluations. * Previous liver disease or clinically significant elevations in serum transaminases at the screening. * Acute or chronic diseases and/or clinical finding which may interfere with the aims of the study or with the drug's safety, tolerability, bioavailability and/or pharmacokinetics of the IMP. * History of kidney disease and with impaired renal function. * History of severe allergy or allergic reactions to the study IMP, its excipients or related drugs. * Clinically significant illness within 28 days before the first dosing, including major surgery. * Any significant clinical abnormality including Hepatitis B surface antigen (HBsAg), hepatitis C virus (HCV), and / or (human immunodeficiency virus) HIV. (On screening). * Positive result of blood pregnancy test at screening or positive urine pregnancy test at check-in or breast-feeding or lack of results of pregnancy test. * Positive results of drugs of abuse in urine at screening and at check-in. * Positive result of alcohol breath test at screening and at check-in. * Positive result of urine cotinine test at screening and at check-in. * Serious mental disease and/or inability to cooperate with clinical team. * Sitting blood pressure after a minimum of 5 minutes of rest is out of the range of 90-140 mmHg for systolic blood pressure (BP) and/or 60-90 mmHg for diastolic BP and/or heart rate out of the range of 50-100 bpm during the screening procedure. * Body ear temperature is out of the range of 35.7 - 37.3°C at screening and at check-in. * Orthostatic hypotension during the screening procedure. * Drug, alcohol (of ≥ 40 g per day pure ethanol), solvents or caffeine abuse. * Use of organ-toxic drugs or systemic drugs known to substantially alter liver metabolism within 90 days before the first dosing. * Use of any prescription medication for a period of 28 days before the first dosing. * Use of any OTC (over-the-counter) medication including vitamins, herbal medications and food supplements less than 14 days before the first dosing. * Getting a tattoo, body piercing or any cosmetic treatment involving skin piercing within 90 days before the screening unless evaluated by Investigator as non-significant for inclusion in the study. * Donation or loss of at least 500 mL of blood within 90 days or donation of plasma or platelets within 14 days before the first dosing. * Anemia, haemoglobin below 120 g/L for women and 130 g/L for men at screening. * Less than 30 days between exit procedure in previous study and the first dosing in in this study.