Phase I/pilot study of SU5416 (semaxinib) in combination with irinotecan/bolus 5-FU/LV (IFL) in patients with metastatic colorectal cancer.
OBJECTIVE
Determine the toxicity, tolerability, and pharmacokinetics of SU5416, a vascular endothelial growth factor receptor-2 (VEGFR-2) tyrosine kinase inhibitor, coadministered with bolus 5-fluorouracil (5-FU), leucovorin, and irinotecan (IFL) in untreated patients with metastatic colorectal cancer.


METHODS
SU5416 (85 or 145 mg/m2) was administered twice weekly throughout a 6-week period along with standard IFL (4 weeks on/2 weeks off). Plasma samples were assayed for SU5416, irinotecan, and SN-38 by reverse-phase HPLC. Contrast enhanced, color Doppler sonography was performed on patients at the MTD to identify changes in tumor perfusion.


RESULTS
Eleven patients received treatment with SU5416 85 mg/m2 (n = 5) or 145 mg/m2 (n = 6). At 85 mg/m2, no DLTs were observed. At 145 mg/m2, grade 3 diarrhea and vomiting were observed during cycle 1; other grade 3 toxicities included fatigue, nausea, anorexia, anemia, pain, urinary retention, and hypertension. The pharmacokinetics of irinotecan and SN-38 were not altered by coadministration of SU5416. SU5416 pharmacokinetics were not altered by IFL. Contrast-enhanced, color Doppler sonography was performed on 2 patients and demonstrated reduced tumor perfusion after treatment in a patient who responded to treatment and increased perfusion in a patient who developed progressive disease. Three patients (27%) had confirmed partial responses, 2 patients (18%) had unconfirmed partial responses, and 4 patients (36%) had stable disease.


CONCLUSIONS
Twice weekly SU5416 can be administered with bolus IFL without unexpected toxicities or altering the pharmacokinetic behavior of the administered drugs. Changes in tumor blood perfusion can be detected by contrast-enhanced, color Doppler sonography. The further development of SU5416 was halted before this study was completed.
Lockhart
Albert Craig
AC
Vanderbilt University Medical Center, Nashville, TN, USA. craig.lockhart@vanderbilt.edu
Cropp
Gillian F
GF
Berlin
Jordan D
JD
Donnelly
Edwin
E
Schumaker
Robert D
RD
Schaaf
Larry J
LJ
Hande
Kenneth R
KR
Fleischer
Arthur C
AC
Hannah
Alison L
AL
Rothenberg
Mace L
ML
D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000473:pathology; D004334:Drug Administration Schedule; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D007211:Indoles / Q000008:administration & dosage; D007262:Infusions, Intravenous; D007275:Injections, Intravenous; D000077146:Irinotecan; D002955:Leucovorin / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D011758:Pyrroles / Q000008:administration & dosage; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000037:antagonists & inhibitors / Q000502:physiology
D007211:Indoles; D011758:Pyrroles; C116890:Semaxinib; D000077146:Irinotecan; D040301:Vascular Endothelial Growth Factor Receptor-2; D002955:Leucovorin; D005472:Fluorouracil; D002166:Camptothecin