Eskandary F, et al. - This first-in-patient phase 1b trial was undertaken to determine the safety/tolerability and classical pathway (CP)-blocking potential of four weekly doses (60 mg/kg) of the anti-C1s antibody BIVV009 in complement-mediated disorders. Findings suggested that BIVV009 effectively blocked alloantibody-triggered CP activation, even though short-course treatment indicated no effect on indices of activity in late antibody-mediated rejection (ABMR). To clarify the therapeutic value of CP blockade in transplantation, this initial trial seemed to provide a valuable basis for future studies.