Phase 1b
DLTs
Twenty patients were enrolled in the CRC cohort in phase 1b; 8 and 12 patients, respectively, received 560 mg and 840 mg ibrutinib with cetuximab. Median duration of ibrutinib exposure was 2.7 months and median cetuximab exposure was 2.3 months. Eleven patients were DLT-inevaluable, 10 due to dose interruption because of non-DLT AEs and one due to dosing non-compliance. Among the nine DLT-evaluable patients in this cohort, there were no reported DLTs. Therefore, the RP2D used in phase 2 was 840 mg ibrutinib orally daily plus 400 mg/m