TABLE 2

IC50 values and 95% confidence intervals (CIs) for inhibition of OATP-mediated transport (E217G for OATP1B1 and OATP1B3 and E1S for OATP2B1)

Cell LineCompoundIC5095% CI
μM
OATP1B1Silymarin1.3a1.0–1.6
Silybin A9.7b5.3–17.7
Silybin B8.5b5.6–12.9
Silychristin9.0b6.0–13.4
OATP1B3Silymarin2.2c1.1–4.7
Silybin A2.7c0.7–11.0
Silybin B5.0c0.5–52.4
Silychristin36.4c1.6–855
OATP2B1Silymarin0.3a0.2–0.7
Silybin A4.5b2.7–7.8
Silybin B0.8b0.6–1.1
Silychristin3.6a2.5–4.0
  • a Four parameter fit.

  • b Three parameter fit with fixed bottom.

  • c Three parameter fit with fixed top; IC50 values were estimated from a maximal inhibition that was less than 100%.