A Stratified Analysis of Supersaturation and Precipitation Effects Based on the Refined Developability Classification System (Rdcs).

Supersaturation and precipitation within the gastrointestinal tract can influence oral absorption of active pharmaceutical ingredients (APIs). Supersaturation of weakly basic APIs upon transfer from the stomach into the small intestine may enhance their absorption, while salt forms of poorly soluble weak acids may generate supersaturated solutions in both stomach and intestine. Likewise, APIs with solubility-limited absorption may be developed as enabling formulations intended to produce supersaturated solutions of the API in the gut. Integrating the supersaturation/precipitation characteristics of the API into the biopharmaceutical risk classification enables comprehensive mapping of potential developability risks and guides formulation selection towards optimizing oral bioavailability (BA). The refined Developability Classification System (rDCS) provides an approach for this purpose. In this work, the rDCS strategy is revisited and a stratified approach integrating the in vitro supersaturation and precipitation behavior of APIs and their formulations is proposed.