Fosbretabulin

Combretastatin A-4 phosphate

Identifiers
IUPAC name Phosphoric acid mono-{2-methoxy-5-[(Z)-2-(3,4,5-trimethoxy-phenyl)-vinyl]-phenyl} ester
Synonyms	CA4P; CA4PD; fosbretabulin; fosbretabulin disodium
PubChem CID	5351387
ChemSpider	4508406
Chemical and physical data
Formula	C18H21O8P
Molar mass	396.32 g/mol (exact mass : 396.097404)
3D model (Jmol)	Interactive image
SMILES O=P(O)(O)Oc1c(OC)ccc(c1)\C=C/c2cc(OC)c(OC)c(OC)c2
InChI InChI=1S/C18H21O8P/c1-22-14-8-7-12(9-15(14)26-27(19,20)21)5-6-13-10-16(23-2)18(25-4)17(11-13)24-3/h5-11H,1-4H3,(H2,19,20,21)/b6-5- Key:WDOGQTQEKVLZIJ-WAYWQWQTSA-N

Combretastatin A-4 phosphate (phosbretabulin, and its salt phosbretabulin disodium) is a microtubule destabilising drug, a type of vascular-targeting agent, a drug designed to damage the vasculature (blood vessels) of cancer tumours causing central necrosis. It is a derivative of combretastatin.

Combretastatin A-4 phosphate (CA4P) is a prodrug. In vivo, it is dephosphorylated to its active metabolite, combretastatin A-4.

CA4P is also known as Fosbretabulin Tromethamine.

In July 2007 the pharmaceutical company OXiGENE initiated a 180-patient phase III clinical trial of CA-4-P in combination with carboplatin for the treatment of anaplastic thyroid cancer. There is currently no fully FDA approved treatment for this form of cancer.

By 2017 it had completed multiple clinical trials (e.g. for solid tumours, non-small cell lung cancer) with more in progress.