DOI: 10.3109/00498254.2013.878815
Effects of artemisinin antimalarials on CYP enzymes 11
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Conclusions
The data presented in this study show that the artemisinin
class of endoperoxides are inhibitors of CYP enzymes
in vitro, with the most prominent effects on CYP1A2, 2B6,
2C19 and 3A4. Together, these four enzymes are responsible
for the clearance mechanisms for 60% of the drugs currently
marketed (Zanger et al., 2008). Some of the predicted risks
of DDIs in vivo reported in the present study are supported
by previously published data with respect to CYP1A2.
However, the risk of interactions caused by a net inhibition
may be overpredicted in some cases due to the ability of
artemisinin drugs to induce several CYP isoforms (Asimus
et al., 2007; Elsherbiny et al., 2008; Mihara et al., 1999;
Svensson et al., 1998; Xing et al., 2012). Furthermore,
their ability of artemether and artemisinin to autoinduce their
own metabolism, resulting in decreasing exposure over
time could have an impact on the inhibitory outcome
(Ashton et al., 1998a; Gordi et al., 2002; Simonsson et al.,
2003; van Agtmael et al., 1999a).
Declaration of interest
The authors report no declarations of interest.
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