This study was conducted to determine maximum tolerated dose ( MTD ) , dose-limiting toxicities ( DLTs ) , pharmacokinetics ( PKs ) , and antitumor activity of escalating doses of tivozanib with a modified ( m ) FOLFOX-@ ( leucovorin , @-fluorouracil -LSB- @-FU -RSB- , and @ mg/kg ( @ ) oxaliplatin ) regimen in patients with advanced gastrointestinal tumors .