Synthesis and evaluation of water-soluble polyethylene glycol-paclitaxel conjugate as a paclitaxel prodrug.
Water-soluble paclitaxel may cause less side effects and be less costly to administer in comparison to a taxol formulation using a cremophor EL/alcohol vehicle. In this study, polyethylene glycol (PEG; MW 5000) was conjugated to the 2' position of paclitaxel through a spacer succinyl group. PEG-paclitaxel as a non-ionic paclitaxel prodrug was highly water soluble (> 20 mg equiv. paclitaxel/ml). The release of paclitaxel from phosphate-buffered solution was pH dependent. The half-life of PEG-paclitaxel was 7.6, 54 and 311 min at pH 9.0, 7.4 and 6.0, respectively. PEG-paclitaxel inhibited the growth of B16 melanoma cells to an extent similar to that of paclitaxel. In MCA-4 mammary tumor-bearing mice, a single dose of PEG-paclitaxel (40 mg equiv. paclitaxel/kg body weight) significantly delayed tumor growth. The average number of days for the tumor to reach 12 from 8 mm in diameter increased from 6.5 days for control animals to 8.5 days for PEG-paclitaxel-treated animals and 9.4 days for paclitaxel-treated animals. These studies demonstrated that PEG may be used as an effective solubilizing carrier for paclitaxel.
Li
C
C
Division of Diagnostic Imaging, University of Texas, MD Anderson Cancer Center, Houston 77030, USA.
Yu
D
D
Inoue
T
T
Yang
D J
DJ
Milas
L
L
Hunter
N R
NR
Kim
E E
EE
Wallace
S
S
D000818:Animals; D004354:Drug Screening Assays, Antitumor; D005260:Female; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy*; D008545:Melanoma / Q000188:drug therapy*; D051379:Mice; D017239:Paclitaxel / Q000737:chemistry / Q000627:therapeutic use*; D011092:Polyethylene Glycols / Q000737:chemistry; D011355:Prodrugs / Q000138:chemical synthesis / Q000627:therapeutic use*; D014407:Tumor Cells, Cultured / Q000187:drug effects
D011355:Prodrugs; D011092:Polyethylene Glycols; D017239:Paclitaxel