A generic drug is a copy of an already approved brand-name drug (reference medicinal product) whose patent protection has expired. It contains the same active ingredient in the same dosage and pharmaceutical form and is equivalent to the original product in terms of its quality, safety, and efficacy.
The crucial advantage for generic drug manufacturers is that they do not have to repeat extensive preclinical and clinical studies (Phase I-III) to re-demonstrate the safety and efficacy of the active ingredient. Instead, they must prove in a bioequivalence study that their product exhibits the same bioavailability in the human body as the reference medicinal product. If this proof is successful, the generic drug can be brought to market at a significantly lower price, as the high research and development costs are eliminated. CROs play an important role in conducting these critical bioequivalence studies.