The longer-term therapeutic effects of orally-administered SPION-RLX or SPION-B7-33, a single-chain RLX-derivative which activates relaxin family peptide receptor 1 (RXFP1) at the same site as RLX [18], was also evaluated in comparison to the orally-delivered angiotensin-converting enzyme inhibitor, perindopril, in mice with established cardiomyopathy and LV fibrosis. The gene discussed is RXFP1; the disease is cardiomyopathy.