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Updated: Jul 9, 2026
09:24
Application and Methodology of the Non-destructive 19F Time-domain NMR Technique to Measure the Content in Fluorine-containing Drug Products
Published on: August 22, 2017
Pharmacokinetics and safety of nafamostat and its metabolites following single- and multiple-dose oral administration
Jun Ki Hong1, Hyun Chul Kim1, In-Jin Jang1
1Department of Clinical Pharmacology and Therapeutics, Seoul National University Hospital, Seoul National University College of Medicine, Seoul 03080, Korea.
Translational and Clinical Pharmacology
|July 8, 2026
Summary
Oral nafamostat mesylate, a potential antiviral, demonstrated good tolerability in healthy males. Pharmacokinetics showed dose-proportional metabolite exposure and good safety for the new oral formulation.
Area of Science:
- Pharmacology
- Drug Development
- Virology
Background:
- Nafamostat mesylate, a serine protease inhibitor, shows potential as an antiviral agent against SARS-CoV-2.
- An oral formulation is being developed to enhance patient compliance compared to the existing intravenous route.
Purpose of the Study:
- To evaluate the pharmacokinetics (PKs) and safety of single and multiple oral doses of nafamostat mesylate in healthy male participants.
- To assess the PKs of nafamostat and its metabolites, 6-amidino-2-naphthol (AN) and 4-guanidinobenzoic acid (GBA).
Main Methods:
- An open-label, single-dose and multiple ascending dose (MAD) study was conducted.
- Participants received single 200 mg dose or multiple ascending doses (100, 200, 400 mg QID) for 7 days.
- PKs and safety/tolerability were assessed throughout the study.
Main Results:
- Nafamostat exposure was more than dose-proportional, while metabolite exposures (AN, GBA) were dose-proportional.
- Terminal elimination half-lives varied: nafamostat (0.61-3.84 h), AN (21.24-31.44 h), GBA (8.28-14.70 h).
- No serious adverse events were reported; oral nafamostat mesylate was well-tolerated up to 400 mg QID.
Conclusions:
- Oral nafamostat mesylate exhibits favorable pharmacokinetics and is well-tolerated in healthy male participants.
- The study supports the development of an oral formulation of nafamostat mesylate for potential antiviral applications.
- Further research is warranted to explore its efficacy in treating viral infections.
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