PEG-SN38 Shows Anti-Tumor Activity in Resistant Models

BRIDGEWATER, New Jersey—Enzon Pharmaceuticals, Inc.'s PEG-SN38, a novel polyethyleneglycol-SN38 conjugate, resulted in significant tumor growth inhibition in mice resistant to irinotecan (Camptosar) (a 25% decrease in tumor volume) and outperformed irinotecan when given as a second-round therapy to mice initially sensitive to irinotecan, the company said in a news release. The data were presented at the American Association for Cancer Research 2007 meeting (abstract 1494). Additionally, PEG-SN38 demonstrated long-lasting anti-tumor activity in mouse models of human breast and pancreatic cancers, the company said.