Herein we describe the development of a focused series of functionalized pyridazin-3(2 H)-one-based formyl peptide receptor (FPR) agonists that demonstrate high potency and biased agonism. The compounds described demonstrated biased activation of prosurvival signaling, ERK1/2 phosphorylation, through diminution of the detrimental FPR1/2-mediated intracellular calcium (Ca) mobilization. Compound 50 showed an EC of 0.083 μM for phosphorylation of ERK1/2 and an approximate 20-fold bias away from Ca mobilization at the hFPR1.i