Objective:

Primary objective of the present study was to compare the single dose bioavailability of Torrent's Montelukast Sodium 10 mg tablet and Innovator's(Merck)Singulair 10 mg tablet. Dosing periods were separated by a washout period during fasted study.

Study Design:

Open-Label, Randomised, two Period, two treatment, Crossover, Single-Dose Bioequivalence Study

Inclusion Criteria:

• The volunteers were included in the study based on the following criteria:
• Sex: male.
• Age: 18 - 45 years.
• Volunteer with BMI of 18-27 (inclusive both) kg/m2 with minimum of 50 kg weight.
• Healthy and willing to participate in the study.
• Volunteer willing to adhere to the protocol requirements and to provide written informed consent.
• Non-smokers or smoker who smokes less than 10 cigarettes per day

Exclusion Criteria:

• The volunteers were excluded from the study based on the following criteria:
• Clinically relevant abnormalities in the results of the laboratory screening evaluation.
• Clinically significant abnormal ECG or Chest X-ray.
• Systolic blood pressure less than 100 mm Hg or more than 140 mm Hg and diastolic blood pressure less than 60 mm Hg or more than 90 mm Hg.
• Pulse rate less than 50/minute or more than 100/minute.
• Oral temperature less than 95°P or more than 98.6°P.
• Respiratory rate less than 12/minute or more than 20/minute
• History of allergy to the test drug or any drug chemically similar to the drug under investigation.
• History of alcohol or drug abuse
• Positive breath alcohol test
• Recent history of kidney or liver dysfunction.
• History of consumption of prescribed medication since last 14 days or OTC medication since last 07 days before beginning of the study.
• Volunteers suffering from any chronic illness such as arthritis, asthma etc.
• History of heart failure.
• HIV, HCV, HBsAg positive volunteers.
• Opiate, tetra hydrocannabinol, amphetamine, barbiturates, benzodiazepines, - - - Cocaine positive volunteers based on urine test.
• Volunteers suffering from any psychiatric (acute or chronic) illness requiring medications.
• Administration of any study drug in the period 0 to 3 months before entry to the study.
• History of significant blood loss due to any reason, including blood donation in the past 3 months.
• History of pre-existing bleeding disorder.
• Existence of any surgical or medical condition, which, in the judgment of the chief investigator and/or clinical investigator/physician, might interfere with the absorption, distribution, metabolism or excretion of the drug or likely to compromise the safety of volunteers.
• Inability to communicate or co-operate due to language problem, poor mental development or impaired cerebral function.