Biopharmaceutics Classification System Redefining BSC Solubility Class Boundary

Biopharmaceutics Classification System Redefining BSC Solubility Class Boundary 

Solubility, dissolution rate, and intestinal permeability, are the major bio-pharmaceutic factors that affect the rate and extent of absorption of an oral drug product. Particularly for water insoluble drugs that have generally high membrane permeability (BCS Class II), dissolution, and dose are the most critical factors affecting the rate and the extent of oral absorption. 

Class Permeability Solubility IVIV correlation expectation 

Class I High High IVIV correlation not expected if dissolution is rapid. Gastric emptying is rate determining. 

Class II Low High IVIV correlation expected if in vitro dissolution rate is similar to in vivo dissolution rate (unless dose is very high). 

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