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Published on: December 17, 2021
Development of a novel osmotically driven drug delivery system for weakly basic drugs
1Pharmaceutical Development, Bayer Schering Pharma AG, Berlin, Germany.
Summary
Controlled release pellets for SAG/ZK were developed to achieve pH-independent drug release. Incorporating osmotically active ingredients into the pellet core enabled pH-independent, osmotically driven drug release.
Area of Science:
- Pharmaceutical Sciences
- Drug Delivery Systems
Background:
- SAG/ZK drug substance exhibits a short biological half-life and pH-dependent solubility due to its weakly basic nature.
- Developing a controlled release (cr) formulation for SAG/ZK with pH-independent drug release is crucial for consistent therapeutic outcomes.
Purpose of the Study:
- To develop a multiple-unit pellet formulation for SAG/ZK with pH-independent drug release.
- To investigate the effect of osmotically active additives on drug release mechanisms.
Main Methods:
- Pellets were prepared using extrusion/spheronization with a 60% drug load.
- Pellets were coated with an extended-release polyvinyl acetate/polyvinyl pyrrolidone dispersion (Kollidon SR 30 D).
- A second enteric coating layer of methacrylic acid and ethyl acrylate copolymer (Kollicoat MAE 30 DP) was applied, with varying inclusion of osmotically active agents (sodium chloride, potassium chloride, sucrose).
Main Results:
- Initial extended-release coated pellets showed pH-dependent drug release.
- The addition of an enteric coat alone did not achieve pH-independent release and reversed the pH-dependency.
- Pellets containing osmotically active ingredients demonstrated increased fluid imbibing, pore formation, and significantly increased drug release rates.
- pH-independent, osmotically driven SAG/ZK release was achieved from double-layered pellets with osmotically active ingredients.
Conclusions:
- Incorporating osmotically active ingredients into the pellet core is essential for achieving pH-independent drug release from double-layered controlled-release pellets.
- Osmotically driven release mechanisms can overcome pH-dependent solubility issues for weakly basic drugs like SAG/ZK.
- The developed formulation offers a promising approach for consistent drug delivery of SAG/ZK, independent of gastrointestinal pH.
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