Conformationally stable peptide analogs of the response selective C5a agonist EP67 having the formula Tyr Ser Phe Lys Asp Met Xaa (Xaa2) (D Ala) Arg (SEQ ID NO:1) wherein Xaa is a modified proline residue or a residue substitution for proline and Xaa2 is leucine or N methyl leucine. The conformationally stable peptides selectively bind and activate APCs without directly engaging/binding C5a receptor bearing cells involved in pro inflammatory activities of natural C5a. Compositions and methods of using the peptide analogs are also described.