Riliprubart (SAR445088) is an anti-C1s humanized monoclonal antibody that inhibits activated C1s in the proximal portion of the classical complement system. Riliprubart selectively inhibits activated C1s and prevents the enzymatic action of C1 on its substrates C4 and C2, thus inhibiting the formation of the classical pathway C3 convertase, C4b2a[1].
