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Optimizing the Growth of Endothiapepsin Crystals for Serial Crystallography Experiments
Published on: February 4, 2021
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Accelerated stability modeling of recrystallization from amorphous solid Dispersions: A Griseofulvin/HPMC-AS case
Ariana Sheng-Chu Leon1, Kenneth C Waterman2, Guanhua Wang1
1Level 2, Block C3, Maple Science Park, Qixia District, Nanjing 210048 China.
International Journal of Pharmaceutics
|May 3, 2024
Summary
Predicting recrystallization in amorphous solid dispersions (ASDs) is crucial for drug stability. This study uses an accelerated stability assessment program (ASAP) to accurately model shelf-life and prevent drug crystallization.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
- Physical Chemistry
Background:
- Amorphous solid dispersions (ASDs) enhance oral bioavailability of poorly water-soluble drugs.
- Predicting ASD crystallization during storage is vital but challenging due to quantification limits and complex kinetics.
- Current methods for predicting ASD stability are time-consuming and have limited accuracy.
Purpose of the Study:
- To develop and validate a predictive shelf-life model for amorphous solid dispersions (ASDs) using an accelerated stability assessment program (ASAP).
- To improve the accuracy of predicting ASD crystallization levels by employing advanced kinetic modeling techniques.
- To establish a reliable method for assessing the long-term stability of ASDs under various stress conditions.
Main Methods:
- Preparation of a model amorphous solid dispersion (ASD) using spray drying (griseofulvin and HPMC-AS-LF).
- Application of the accelerated stability assessment program (ASAP) with isoconversion and modified Arrhenius approach below the glass transition temperature (Tg).
- Development and utilization of a sensitive X-ray powder diffraction (XRPD) method for crystal content quantification in stressed ASD samples.
Main Results:
- The ASAPprime® modeling showed good agreement with long-term (40°C/75%RH) crystallinity levels.
- Developed XRPD method provided sensitive quantification of crystal content in stressed ASDs.
- Accelerated stability studies demonstrated potential for improving ASD shelf-life prediction accuracy.
Conclusions:
- The accelerated stability assessment program (ASAP) effectively predicts crystallization in amorphous solid dispersions (ASDs).
- This approach enhances the accuracy of shelf-life predictions for ASDs, crucial for drug product development.
- The study supports the use of ASAP for reliable and efficient stability assessment of amorphous solid dispersions.
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