Ixekizumab, sold under the brand name Taltz, is an injectable medication for the treatment of autoimmune diseases. Chemically, it is a form of a humanized monoclonal antibody. The substance acts by binding interleukin 17A and neutralizing it, reducing inflammation. The most common side effects include upper respiratory infections, injection site reactions and fungal (tinea) infections. The drug was developed by Eli Lilly and Co. and is approved for the treatment of plaque psoriasis in the European Union and the United States.