Bioequivalence Study Comparing Rifampicin In A Fixed-Dose Combination (Rifampicin+Isoniazid, Myrin© 2) And The Reference Drug (Rifampicin, Rimactane®)

This study is done to demonstrate bioequivalence of rifampicin component in Myrin© 2 Fixed-Dose Combination Tablet (each contains 75 mg isoniazid and 150 mg rifampicin, Pfizer Inc) with equivalent dose of the reference Rimactane® capsule (each contains 300 mg rifampicin, Novartis Sandoz) in healthy Filipino male subjects. This study also aims to determine the safety and tolerability of Myrin© 2 tablets and Rimactane® capsules in these subjects.


Eligibility Criteria:
Inclusion Criteria:

* Healthy male subjects between the ages of 18 and 55 years, inclusive.
* Body Mass Index (BMI) of 17.5 to 30.5 kg/m2; and a total body weight \>50 kg (110 lbs).
* An informed consent document signed and dated by the subject.
* Subjects willing and able to comply with scheduled visits, treatment plan, laboratory tests, and other study procedures.

Exclusion Criteria:

* Evidence or history of clinically significant hematological, renal, endocrine, pulmonary, gastrointestinal, cardiovascular, hepatic, psychiatric, neurologic, or allergic disease (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at time of dosing).
* Any condition possibly affecting drug absorption (e.g., gastrectomy).
* A positive urine drug screen.
* History of regular alcohol consumption exceeding 21 drinks/week (1 drink = 5 ounces (150 ml) of wine or 12 ounces (360 ml) of beer or 1.5 ounces (45 ml) of hard liquor) within 6 months of screening.
* Treatment with an investigational drug within 3 months (or as determined by the local requirement, whichever is longer) or 5 half-lives preceding the first dose of study medication.
* 12-lead ECG demonstrating QTc \>450 msec at screening. If QTc exceeds 450 msec, the ECG should be repeated two more times and the average of the three QTc values should be used to determine the subject's eligibility.
* History of previous treatment for TB or is suspected of suffering from TB.
* Use of prescription or nonprescription drugs and dietary supplements within 7 days or 5 half-lives (whichever is longer) prior to the first dose of study medication. Herbal medication, herbal supplements and hormone replacement therapy must be discontinued 28 days prior to the first dose of study medication. As an exception, acetaminophen / paracetamol may be used at doses of less than 1 g/day. Limited use of non-prescription medications that are not believed to affect subject safety or the overall results of the study may be permitted on a case-by-case basis following approval by the sponsor.
* Blood donation of approximately 1 pint (500 ml) within 56 days prior to dosing.
* A history of hypersensitivity to any of the study medications or related substances, or to any of the ingredients used in the study drug formulations.
* Unwilling or unable to comply with the Lifestyle guidelines described in this protocol.
* Other severe acute or chronic medical or psychiatric condition or laboratory abnormality that may increase the risk associated with study participation or investigational product administration or may interfere with the interpretation of study results and, in the judgment of the investigator, would make the subject inappropriate for entry into this study.
* Recent history of diarrhea (2 weeks).
* Recent use of oral (2 weeks) or IV (2-3 months) antibiotics to assure normal bowel flora at study start.