A phase 1 study of 6 Japanese patients with advanced/recurrent gastric cancer (JapicCTI‐142420) found that the PK and safety profiles of napabucasin were not affected by paclitaxel, a CYP2C8 and CYP3A4 substrate.18, 49, 50. This evidence concerns the gene CYP2C8 and gastric cancer.