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Optimized Griess Reaction for UV-Vis and Naked-eye Determination of Anti-malarial Primaquine
Published on: October 11, 2019
Biowaiver monographs for immediate-release solid oral dosage forms: primaquine phosphate
Anita Nair1, Bertil Abrahamsson, Dirk M Barends
1Institute of Pharmaceutical Technology, Goethe University, Frankfurt am Main, Germany.
Journal of Pharmaceutical Sciences
|December 14, 2011
Summary
Primaquine phosphate, a highly soluble and permeable antimalarial drug, can be approved using a biowaiver for immediate-release oral dosage forms. This avoids in vivo bioequivalence testing if dissolution criteria are met.
Area of Science:
- Pharmaceutical Sciences
- Drug Development
- Regulatory Affairs
Background:
- Primaquine phosphate is an essential antimalarial drug.
- Immediate-release solid oral dosage forms require bioequivalence (BE) testing for approval.
- Biopharmaceutical Classification System (BCS) aids in waiving in vivo BE studies.
Purpose of the Study:
- To review literature data supporting a biowaiver for primaquine phosphate immediate-release oral dosage forms.
- To assess primaquine phosphate's suitability for biowaiver based on its physicochemical properties and dissolution profiles.
Main Methods:
- Literature review of primaquine phosphate solubility, permeability, and therapeutic index.
- Analysis of Biopharmaceutical Classification System (BCS) classification.
- Evaluation of dissolution data for immediate-release primaquine phosphate products.
Main Results:
- Primaquine phosphate is classified as BCS Class I (highly soluble, highly permeable).
- Existing products demonstrate rapid or very rapid dissolution.
- No published data indicate bioinequivalence issues with immediate-release primaquine phosphate products.
Conclusions:
- A biowaiver for primaquine phosphate immediate-release oral dosage forms is recommended.
- Conditions include using approved excipients and meeting stringent dissolution criteria.
- This streamlines the approval process for generic primaquine phosphate products.
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