The concepts such as Bioavailability (BA) and Bioequivalence (BE) play a crucial role in determining the dosage levels of new drugs to the clinical trial participants. This is a major part of the clinical research studies as the whole trial processes are completely dependent on the effectiveness of newly developed drugs. Thus, the clinical research course is the perfect starting for interested students to get in-detailed concepts of each clinical processes.


Bioavailability is the relative quantity of a drug with respect to an administered dosage and the rate of dosage with intent to enter in systemic circulation. Drug bioavailability is determined by measuring the concentrations of the active ingredient (API) and its metabolites in plasma or serum. The API concentration also influences active component release from therapeutic molecules, as well as absorption, circulation, metabolism, and elimination.

Whereas Bioequivalence means when taken at the same molar dose, a drug product's extent and rate of absorption are not statistically very different from those of the reference product. These studies are carried out to evaluate the efficacy of a novel medication product that may contain a number of different diluents or inactive chemicals. Drug bioequivalence is assessed by determining if different formulations allow the same amount of active component and effectiveness in the body.

Relevance of BA/BE studies

Drug Development

Various therapeutic compounds are evaluated for bioavailability during the drug discovery process. Low bioavailability can be detrimental for a variety of reasons. Compounds having limited bioavailability may not reach therapeutic levels in systemic circulation or may need a very large dose, which may be costly or hazardous. These chemicals may require further chemical modifications to increase bioavailability. During drug discovery, these difficulties are examined, and the molecule with the best bioavailability and therapeutic value is chosen for future development. The observation of drugs over the patients on basis of their effects or adverse effects comes in pharmacovigilance. Furthermore, these concepts are focused in detail in the pharmacovigilance course.

When it comes to the development of new drugs, it is always a mandatory task of clinical trial regulators to introduce the regulation and protocols related to the patient and drug safety. This helps in steering clear of any adverse events in the possible future situations. Thus a regulatory affairs course allows individuals to learn about the in-field protocols that facilitate the safety of drugs and patients.

Preclinical Research

The researchers rigorously adhere to preclinical bioavailability and bioequivalence study requirements, resulting in secure execution and meaningful data acquisition. After preclinical testing, the most safe and effective medication candidates are chosen for future development.

Clinical Research

When a drug candidate enters the clinical phase, a suitable formulation with the highest bioavailability is created. Because the initial research must begin with a low dose level, tablets are manufactured with only the low dose levels. Higher dosages are provided and shown to be safe as the trial develops. At this point, the medicine must be reformulated with a greater API content. To claim that these many tablets of the lower dose are bioequivalent to a single tablet of the higher dose, the FDA requires bioequivalence studies to be completed.


Incorporation of BA/BE studies into clinical research is detrimental as it provides a base for further exploration in medicine. This could be mastered by taking up professional courses that cover all the topics of clinical research and help students gain perceptive insights.