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Published on: November 27, 2016
Cocrystallization Enables Ensitrelvir to Overcome Anomalous Low Solubility Caused by Strong Intermolecular
Tetsuya Miyano1, Shigeru Ando1, Daiki Nagamatsu1
1Laboratory for Medicinal Chemistry Research, Shionogi & Co., Ltd., Osaka 561-0825, Japan.
Ensitrelvir crystalline forms were studied for treating coronavirus disease 2019. Cocrystallization with fumaric acid significantly improved ensitrelvir
Area of Science:
- Pharmaceutical Sciences
- Crystallography
- Drug Delivery
Background:
- Ensitrelvir is a 3CL protease inhibitor for COVID-19.
- Four crystalline forms (I-IV) of ensitrelvir were identified with varying solubilities.
- Stable Form III exhibits lower solubility than predicted, attributed to specific intermolecular interactions.
Purpose of the Study:
- To investigate the relationship between crystalline structure and ensitrelvir solubility.
- To enhance ensitrelvir solubility and permeation through cocrystallization.
- To understand how altering intermolecular interactions impacts drug properties.
Main Methods:
- Single-crystal structural analysis of ensitrelvir crystalline forms.
- Solubility and dissolution studies across different pH values.
- Cocrystal formation via slurry conversion with fumaric acid.
- Permeation studies to assess drug flux.
Main Results:
- Form III ensitrelvir showed strong triazine-triazole intermolecular interactions.
- A novel cocrystal, Form V (ensitrelvir-fumaric acid), was successfully synthesized.
- Form V exhibited 8-13 fold higher dissolution than Form III.
- Form V demonstrated a 16-fold increase in drug flux compared to Form III.
Conclusions:
- Intermolecular interactions significantly influence ensitrelvir's solid-state properties.
- Cocrystallization is an effective strategy to enhance ensitrelvir solubility and permeation.
- Targeting crystal interactions can optimize drug delivery for COVID-19 treatment.
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