Sophora flavescens (Ku-Shen) as a booster for antiretroviral therapy through cytochrome P450 3A4 inhibition
ZX Lin, CT Che, SS Lee, RCY Chan, PSP Ip, JM Yang
School of Chinese Medicine, School of Biomedical Science, The Chinese University of Hong Kong
Key Messages
1. Sophora flavescens extract dose-dependently inhibited human hepatic CYP3A4 activity. The ethyl acetate (EA) fraction containing prenylated flavonoids was most effective.
2. Sophora EA fraction slightly inhibited the efflux of indinavir from the basolateral to apical side in a Caco-2 cell monolayer model.
3. Unlike ritonavir, coadministration of Sophora EA fraction did not enhance plasma indinavir concentration.
4. Treatment with Sophora total extract significantly decreased plasma exposure of indinavir, associated with intestinal and hepatic P-gp induction, and upregulation of CYP3A activity.
5. Patients prescribed indinavir should be cautioned about intake of S flavescens extract or Sophora-derived products.