ABCC2 and Hyperbilirubinemia: The predictive power of BSEP and MRP2 inhibition was evaluated in only one study [27] which concluded that the Rfree value of >1.1 for BSEP inhibition, in combination with a similar cut-off for OATP1B1 and UGT1A1 inhibition, could be useful in predicting hyperbilirubinemia.