Provided is a bi-specific fusion polypeptide comprising a fynomer sequence that binds to interleukin-17a (IL-17a) and is conjugated to an antibody or subsequence thereof that binds to interleukin-6 receptor (IL-6R). The fusion polypeptide can bind to both IL-17a and IL-6R thereby suppresses, reduces, decreases, inhibits or blocks both IL-17a and IL-6R activities.