Angiotech Pharmaceuticals is halting enrollment in clinical trials for Vascular Wrap, which is being evaluated in patients undergoing surgery for hemodialysis access, pending a safety review. The company has been conducting the study in the U.S. and Europe on two groups, one which received the wrap in combination with a graft and one which received the graft alone. After reviewing a summary of interim adverse events, a data safety monitoring board has informed the company that one of the two study groups had a greater incidence of implant site infection.