poly iclc poly iclc poly iclc is an immunostimulant. it is polyinosinic-polycytidylic acid (poly i:c) mixed with the stabilizers carboxymethylcellulose and polylysine. it is under trial for use in cancer. poly iclcclinical dataatc codel03ax08 (who) identifierschemspidernone (verify) poly i:c is a ligand for toll like receptor-3, which usually triggers on the structurally similar double-stranded rna present in some viruses.