Basic information about Bioequivalence study of pharmaceutical products are given below as per USFDA/EMEA/CANADA/WHO - 


Covered topic: Fasting & Fed study

1. Recommended study:

Fasting study

(also Fed study if required.)


A fast means that no food or solids are to be consumed, although alcohol‐free, xanthine‐free and flavonoid‐free clear fluids are permissible the night prior to the study.


> overnight fasting (10 hours at least)

> Take TP & RP with 240 ml / 8 ounces of water

> no food - at least 4 hours post dose

> Water can be allowed as desired except for 1 hr before and after drug administration.

> One hour after drug administration xanthine free and flavonoid free fluids are permitted.

> Subjects should receive standardized meals scheduled at the same time in each period of the study.

> abstain from alcohol 24 hour before study to last sample collection.

> When comparing the performance of two orally disintegrating dosage forms that are intended to be taken without water, the comparative bioavailability study should be designed to challenge the formulation under the most discriminatory conditions. For such dosage formulations, water should not be administered from one hour prior to dosing, concurrent with dosing and up to one hour post dosing.



Fed Study

Take the meal ‌> having greatest effects on GI physiology > so that systemic drug availability is maximally affected.

= high-fat

= high-calorie


An example of test meal:

> two eggs fried in butter,

> two strips of bacon,

> two slices of toast with butter,

> four ounces /120 gm of hash brown potatoes and

> eight ounces/ 240 ml of whole milk.


> overnight fast (10 hours at least)

> recommended meal 30 minutes prior to drug administration

> Study subjects should eat this meal in 30 minutes or less; however, the drug product should be administered 30 minutes after start of the meal.

> Drug + 240 mL (8 fluid ounces) of water.

> no food - at least 4 hours post dose .

> Water can be allowed as desired except for 1 hr before and after drug administration.

> Subjects should receive standardized meals scheduled at the same time in each period of the study.

> abstain from alcohol 24 hour before study to last sample collection


Posture and physical activity

Subjects should not be allowed to recline until at least two hours after drug ingestion.

Physical activity and posture should be standardized as much as possible to limit effects on gastrointestinal blood flow and motility.


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