The global pharmaceutical market increasingly depends on the interchangeability of branded and generic drug products to improve healthcare accessibility and reduce treatment costs. To ensure therapeutic consistency, generic medicines are required to demonstrate pharmaceutical and therapeutic equivalence to their branded counterparts through stringent regulatory evaluation procedures. Among these procedures, dissolution testing serves as a critical surrogate indicator of in vivo drug performance and plays a central role in assessing product quality, bioavailability, and bioequivalence. The Biopharmaceutics Classification System (BCS)-based biowaiver approach has emerged as a scientifically justified strategy that permits the waiver of costly and ethically demanding in vivo bioequivalence studies by relying primarily on in vitro dissolution data, provided specific regulatory criteria are fulfilled. This review critically evaluates published scientific evidence concerning the comparative dissolution behavior of branded and generic oral solid dosage forms, with particular emphasis on the application of BCS-based biowaiver principles under WHO, FDA, EMA, and ICH regulatory frameworks. Comparative dissolution studies indicate that although many generic products demonstrate dissolution profiles comparable to innovator products, variations may occur due to differences in excipient composition, manufacturing processes, particle size distribution, and polymorphic characteristics of the active pharmaceutical ingredient. The similarity factor (f2) remains the most widely accepted regulatory tool for dissolution profile comparison despite recognized statistical limitations. BCS Class I and III drugs continue to be the primary candidates for biowaiver approval, while selected Class II drugs may qualify under specific conditions. Overall, BCS-based biowaiver approaches represent a scientifically reliable, economically beneficial, and ethically sound alternative to in vivo bioequivalence studies when applied using validated dissolution methodologies and harmonized regulatory standards.

Keywords: Biowaiver; Dissolution profile; Generic drugs; Branded drugs; BCS classification; Similarity factor (f2); In vitro dissolution; Pharmaceutical equivalence; Biopharmaceutics Classification System; Therapeutic equivalence.