Ketotifen is a Prodrug. Norketotifen is the active metabolite.

Autor: Aberg AKG; Bridge Pharma, Inc., Sarasota, Florida, USA., Arulnesan N; Department of Toxicology, Nucro-Technics, Scarborough, Ontario, Canada., Bolger GT; GO-TO-PK Solutions, Ajax, Ontario, Canada., Ciofalo VB; Bridge Pharma, Inc., Sarasota, Florida, USA., Pucaj K; Bridge Pharma Toronto, Inc., Scarborough, Ontario, Canada., Walle K; Department of Pharmacology, Medical University of South Carolina, Charleston, South Carolina, USA., Walle T; Department of Pharmacology, Medical University of South Carolina, Charleston, South Carolina, USA.
Jazyk: angličtina
Zdroj: Drug development research [Drug Dev Res] 2022 Apr; Vol. 83 (2), pp. 362-367. Date of Electronic Publication: 2021 Aug 19.
DOI: 10.1002/ddr.21865
Abstrakt: Evaluation of the in vitro human liver microsome and hepatocyte metabolism of ketotifen demonstrated that norketotifen (NK) is the major demethylated hepatic metabolite of ketotifen. It is here reported that NK is completely devoid of the severe and dose-limiting sedative effects of ketotifen. Thus, while ketotifen is clinically dose-limited to 1 mg, bid, there are no dose-limiting sedative effects elicited by NK, even after the highest single-dose (16 mg) or after repeat-doses (8 mg × 7 days) in humans or after the highest doses given to dogs in repeat-dose toxicological studies (40 mg/kg × 14 days). In addition, NK-but not ketotifen-was found to express potent and dose-dependent inhibition of the release of the pro-inflammatory cytokine TNFα from activated human buffy coat preparations. Thus, when used as an anti-inflammatory drug, ketotifen is the sedating prodrug which is converted to NK a nonsedating metabolite with anti-inflammatory activity.
(© 2021 Wiley Periodicals, LLC.)
Databáze: MEDLINE
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