ZD6474 inhibits vascular endothelial growth factor signaling, angiogenesis, and tumor growth following oral administration.
ZD6474 [N-(4-bromo-2-fluorophenyl)-6-methoxy-7-[(1-methylpiperidin-4-yl)methoxy]quinazolin-4-amine]is a potent, p.o. active, low molecular weight inhibitor of kinase insert domain-containing receptor [KDR/vascular endothelial growth factor receptor (VEGFR) 2] tyrosine kinase activity (IC(50) = 40 nM). This compound has some additional activity versus the tyrosine kinase activity of fms-like tyrosine kinase 4 (VEGFR3;IC(50) = 110 nM) and epidermal growth factor receptor (EGFR/HER1; IC(50) = 500 nM) and yet demonstrates selectivity against a range of other tyrosine and serine-threonine kinases. The activity of ZD6474 versus KDR tyrosine kinase translates into potent inhibition of vascular endothelial growth factor-A (VEGF)-stimulated endothelial cell (human umbilical vein endothelial cell) proliferation in vitro (IC(50) = 60 nM). Selective inhibition of VEGF signaling has been demonstrated in vivo in a growth factor-induced hypotension model in anesthetized rat: administration of ZD6474 (2.5 mg/kg, i.v.) reversed a hypotensive change induced by VEGF (by 63%) but did not significantly affect that induced by basic fibroblast growth factor. Once-daily oral administration of ZD6474 to growing rats for 14 days produced a dose-dependent increase in the femoro-tibial epiphyseal growth plate zone of hypertrophy, which is consistent with inhibition of VEGF signaling and angiogenesis in vivo. Administration of 50 mg/kg/day ZD6474 (once-daily, p.o.) to athymic mice with intradermally implanted A549 tumor cells also inhibited tumor-induced neovascularization significantly (63% inhibition after 5 days; P < 0.001). Oral administration of ZD6474 to athymic mice bearing established (0.15-0.47 cm(3)), histologically distinct (lung, prostate, breast, ovarian, colon, or vulval) human tumor xenografts or after implantation of aggressive syngeneic rodent tumors (lung, melanoma) in immunocompetent mice, produced a dose-dependent inhibition of tumor growth in all cases. Statistically significant antitumor activity was evident in each model with at least 25 mg/kg ZD6474 once daily (P < 0.05, one-tailed t test). Histological analysis of Calu-6 tumors treated with 50 mg/kg/day ZD6474 for 24 days showed a significant reduction (>70%) in CD31 (endothelial cell) staining in nonnecrotic regions. ZD6474 also restrained growth of much larger (0.9 cm(3) volume) Calu-6 lung tumor xenografts and induced profound regression in established PC-3 prostate tumors of 1.4 cm(3) volume. ZD6474 is currently in Phase I clinical development as a once-daily oral therapy in patients with advanced cancer.
Wedge
Stephen R
SR
Department of Cancer and Infection Research, AstraZeneca, Cheshire SK10 4TG, United Kingdom. steve.wedge@astrazeneca.com
Ogilvie
Donald J
DJ
Dukes
Michael
M
Kendrew
Jane
J
Chester
Rosemary
R
Jackson
Janet A
JA
Boffey
Sarah J
SJ
Valentine
Paula J
PJ
Curwen
Jon O
JO
Musgrove
Helen L
HL
Graham
George A
GA
Hughes
Gareth D
GD
Thomas
Andrew P
AP
Stokes
Elaine S E
ES
Curry
Brenda
B
Richmond
Graham H P
GH
Wadsworth
Peter F
PF
Bigley
Alison L
AL
Hennequin
Laurent F
LF
D000284:Administration, Oral; D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D016228:Endothelial Growth Factors / Q000037:antagonists & inhibitors* / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D006801:Humans; D008222:Lymphokines / Q000037:antagonists & inhibitors* / Q000502:physiology; D008297:Male; D051379:Mice; D009374:Neoplasms, Experimental / Q000098:blood supply / Q000188:drug therapy / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000188:drug therapy; D010880:Piperidines / Q000494:pharmacology*; D011799:Quinazolines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D020794:Receptor Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D017978:Receptors, Growth Factor / Q000037:antagonists & inhibitors; D040262:Receptors, Vascular Endothelial Growth Factor; D015398:Signal Transduction / Q000187:drug effects; D014407:Tumor Cells, Cultured; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D023041:Xenograft Model Antitumor Assays
D020533:Angiogenesis Inhibitors; D000970:Antineoplastic Agents; D016228:Endothelial Growth Factors; D004791:Enzyme Inhibitors; D008222:Lymphokines; D010880:Piperidines; D011799:Quinazolines; D017978:Receptors, Growth Factor; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D020794:Receptor Protein-Tyrosine Kinases; D040262:Receptors, Vascular Endothelial Growth Factor; C452423:vandetanib