This is a human IgG1 kappa monoclonal antibody using the same sequences as the therapeutic antibody ustekinumab. It is directed against IL12 and IL23, which are cytokines involved in immune and inflammatory responses. Ustekinumab functions by reducing the signaling pathways of IL12 and IL23, downregulating the gene expression of inflammatory cytokines and chemokines such as MCP-1, TNFa, IP-10 and IL8. By binding to the p40 subunit common to IL12 and IL23, it prevents their interaction with IL12 receptor β1 subunit of IL12 and IL23 receptor complexes. Ustekinumab was generated through recombinant human IL12 immunization of human Ig (hu-Ig) transgenic mice. It is a targeted biologic disease-modifying anti-rheumatic drug (bDMARDs) used for managing various inflammatory conditions including plaque psoriasis, psoriatic arthritis, Crohn’s Disease and ulcerative colitis. Biosimilars of ustekinumab have been introduced into certain markets, like Wezlana (ustekinumab-auub) in the US and Jamteki (AVT04) in Canada.