Dasatinib (D) in previously treated metastatic colorectal cancer (mCRC) patients: A phase II trial of the University of Chicago phase II consortium.

506 Background: Dasatinib (Sprycel, Bristol-Myers Squibb), an oral inhibitor of SRC family kinases, inhibits proliferation in CRC cell lines and has antitumor activity in CRC xenograft models. Since treatment options for mCRC are limited after a fluoropyrimidine (F), oxaliplatin (O), and irinotecan (I), novel agents need to be explored in this setting. Methods: We conducted a phase II trial of D in unresectable, previously treated mCRC patients (pts) at 9 centers. No more than 2 prior chemotherapy regimens were permitted, which must have contained F, O and I. Disease progression on or after treatment was required. Eligible patients also had to have measurable disease per RECIST criteria; normal organ function; PS 0-2. Pts received D 70 mg PO BID continuously. CT scans were obtained every 8 weeks. The primary endpoint was progression-free survival (PFS) at 4 months. We employed a Simon, two-stage design with 19 pts enrolled in the first stage, and a second stage planned if ≥ 5 were progression-free at 4 mo...