Human anti-mouse antibody suppression with cyclosporin A

Background. Cyclosporin was used in an attempt to suppress the formation of human antimouse antibody (HAMA) after administration of murine monoclonal antibodies. Methods. Thirteen patients were given oral cyclosporin (8.6-15 mg/kg/day) starting 2 days before administration of technetium-99m ( 99m Tc) labeled F(ab') 2 (3 patients) or Fab (10 patients) murine antibody fragment. Six to nine days later, patients received either rhenium-186 ( 186 Re)-labeled F(ab') 2 or an intact antibody