Agonists for TRAIL death receptors including polypeptides having a multimerizing, e.g. trimerizing, domain and a polypeptide sequence that binds to at least one of TRAIL death receptors TRAIL-Rl and TRAIL-R2. Agonists are described that do not bind to TRAIL decoy receptors. The multimerizing domain may be derived from human tetranectin. The agonists can induce apoptosis in pathogenic cells expressing a TRAIL death receptor. Pharmaceutical compositions are described for treating diseases associated with cells expressing DR4 and DR5, such as tumor cells. Methods for selecting polypeptides and preparing multimeric complexes.
