Campath-1H,LDP-03 Alemtuzumab is a recombinant humanized monoclonal antibody (Campath-1H), which targets the 21-28 kD cell surface glycoprotein CD52. The Campath-1H antibody is of isotype IgG1, with human variable framework and constant regions, and a complementarity determining region derived from a murine (rat) monoclonal antibody (Campath-1G).