The objective of this study is to compare the relative bioavailability of metformin HC1 750 mg extended-release tablets (Ranbaxy) with that of Glucophage® XR 750 mg tablets (Bristol Myers Squibb) in healthy, adult, subjects under fasting conditions.

This study was randomised, two-treatment, two-period, two-sequence, single-dose, crossover bioavailability study planned on 60 healthy, adult, subjects under fasting conditions. 60 subjects were enrolled and 55 subjects completed all the periods of the study. Both periods were separated by a washout period of fourteen days A total of Sixty (60) subjects were enrolled in this study; 55 completed the study.

• Experimental: metformin HC1 750 mg extended-release tablets
• Experimental: Glucophage® XR 750 mg tablets

Inclusion Criteria:

1. All subjects selected for this study will be at least 18 years of age.
2. Each subject shall be given a general physical examination within 28 days of initiation of the study. Such examination includes, but is not limited to, blood pressure, general observations, and history.
3. Each female subject will be given a serum pregnancy test as part of the pre-study screening process. At the end of the study, the subjects will have an exit evaluation consisting of interim history, global evaluation, and clinical laboratory measurements.
4. Adequate blood and urine samples should be obtained within 28 days before beginning of the first period and at the end of the trial for clinical laboratory measurements.
5. Clinical laboratory measurements will include the hematology, clinical chemistry, urine analysis, HIV screening, Hepatitis B & C, drugs of abuse scan

Exclusion Criteria:

1. Subjects with a significant recent history of chronic alcohol consumption or drug addiction (past two years), or serious gastrointestinal, renal, hepatic or cardio- vascular disease, tuberculosis, epilepsy, asthma (past five years), diabetes, psychosis or glaucoma will not be eligible for this study.
2. Subjects whose clinical laboratory test values are outside the reference range may be retested at the discretion of the clinical investigator. If the clinical values are outside the range on retesting, the subject will not be eligible to participate in the study unless the clinical investigator deems the result to not be significant.
3. Subjects who have a history of allergic responses to the class of drug being tested will be excluded from the study
4. All subjects will have urine staples assayed for the presence of drugs of abuse as per of the clinical laboratory screening procedures and at each dosing period check-in. Subjects found to have urine concentrations of any of the tested drugs will not be allowed to participate.
5. Subjects should not have donated blood and/or plasma for at least thirty (30) days prior to the first dosing of the study.
6. Subjects who have taken any investigational drug within thirty (30) days prior to the first dosing of the study will not be allowed to participate
7. Female subjects who are pregnant, breast-feeding, or who are likely to become pregnant during the study will not be allowed to participate. Female subjects of child bearing potential must either abstain from sexual intercourse or use a reliable barrier method (e.g. condom) of contraception during the course of the study (first dosing until last blood collation) or they will not be allowed to participate. Female subjects who have used hormones or contraceptives within 14 days of dosing or implanted or injected hormone contraceptives within 180 days of dosing will not be allowed to participate.

All female subjects will be screened for pregnancy at check-in each study period. Subjects with positive or inconclusive results will be withdrawn from the study