Specific binding peptides having a general schematized structure of an optional N-terminal hinge region joined to an immunoglobulin-derived constant sub-region comprising a CH2 region and a CH3 region, followed by a PIMS linker peptide and at least one specific binding domain are provided, along with encoding nucleic acids, vectors and host cells. Also provided are methods for making such peptides and methods for using such peptides to treat or prevent a variety of diseases, disorders or conditions, as well as to ameliorate at least one symptom associated with such a disease, disorder or condition.