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Published on: July 28, 2023
Adaptive perfusion: An in vitro release test (IVRT) for complex drug products
Deval Patel1, Ying Zhang2, Yixuan Dong3
1Office of Testing and Research, Office of Pharmaceutical Quality, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD 20993, USA; Office of Quality Surveillance, Office of Pharmaceutical Quality, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD 20993, USA.
A novel adaptive perfusion method, a type of tangential flow filtration (TFF), accurately measures drug release rates from complex drug products. This advanced technique offers faster and more comprehensive drug release analysis compared to traditional methods.
Area of Science:
- Pharmaceutical Sciences
- Biophysical Chemistry
Background:
- Drug release testing is crucial for complex formulations like emulsions, suspensions, liposomes, and drug-protein complexes.
- Conventional methods like dialysis can be slow and limited by diffusion rates, hindering accurate characterization of drug release kinetics.
Purpose of the Study:
- To develop and validate an adaptive perfusion method for precise measurement of drug release from particulate drug products.
- To compare the efficacy of adaptive perfusion against conventional dialysis methods for drug release analysis.
Main Methods:
- Developed an adaptive perfusion system utilizing tangential flow filtration (TFF) with pre-conditioned filters.
- Employed size-based separation to simultaneously analyze released and remaining drug.
- Varied filter molecular weight cutoff, feed flow rate, and back-pressure to optimize release measurement.
Main Results:
- Adaptive perfusion successfully discriminated drug release profiles across various formulations (solution, micelles, nanoemulsions of different globule sizes).
- Achieved significantly faster (minutes vs. hours) and higher (e.g., >60%) drug release measurements compared to dialysis.
- Demonstrated robustness and reproducibility through filter pre-conditioning.
Conclusions:
- Adaptive perfusion offers a superior, faster, and more discriminatory method for evaluating drug release from complex drug products.
- The method overcomes limitations of diffusion-based techniques and has potential for assessing manufacturing impacts on drug release.
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