Bioequivalence Study of of Metformin HCl From Gleptomet 50/1000 mg F.C.Tablets (EVA Pharma, Egypt) and Janumet 50/1000 mg F.C.Tablets (Merck Sharp & Dohme, The Netherlands)

Inclusion Criteria: 1. Healthy male or female, age 18 to 55 years, inclusive. 2. Body weight within 15% of normal range (18.5-30.0) according to the accepted normal values for body mass index (BMI). 3. Medical demographics without evidence of clinically significant deviation from normal medical condition, eg.: no history of heart, liver, kidney, gastrointestinal, nervous system, or metabolic abnormalities. 4. Results of clinical laboratory test are within the normal range or with a deviation that is not considered clinically significant by principal investigator. 5. Females should be on a suitable birth control method. 6. Fully informed subjects that consented to participate in the study. Exclusion Criteria: 1. Subjects with known allergy to the products tested. 2. Subjects who meet any of the contraindications to the administration of Sitagliptin and/or Metformin HCl. 3. Subjects who are going to get an injection of dye or contrast agents for an x-ray procedure. 4. Subject does not agree not to consume any medication or food which may affect CYP3A4 enzyme at least one week prior to first study drug administration until donating the last sample of the study. 5. Subjects that do not agree not to consume alcohol-containing beverages and foods for 1 week before dosing and throughout the period of sample collection. 6. Heavy smokers. 7. Female subjects who were pregnant or nursing. 8. Acute infection within one week preceding first study drug administration. 9. History of drug or alcohol abuse. 10. Subject does not comply with the stated instruction of not taking any prescription or non-prescription drugs within two weeks before first study drug administration and until the end of the study. 11. Subject is on a special diet (for example subject is vegetarian). 12. Subject does not agree not to consume any beverages or foods containing methyl-xanthenes e.g. caffeine (coffee, tea, cola, chocolate etc.) 48 hours prior to the study administration of either study period until donating the last sample in each respective period. 13. Subject does not agree not to consume any beverages or foods containing grapefruit 7 days prior to first study drug administration until the end of the study. 14. Subject has a family history of severe diseases which have direct impact on the study. 15. Participation in a bioequivalence study or in a clinical study within the last 60 days, before first study drug administration. 16. Subject intends to be hospitalized within 3 months after first study drug administration. 17. Subjects who have blood donated or lost more than 500 mL blood within 3 months prior to the study.