Discovery of BE2012, a First-in-Class REV-ERBα/β Antagonist with Favorable Selectivity and Pharmacokinetics, and In Vivo Efficacy in Inducing Key Myogenic Factors for Muscle Repair upon Acute Muscle Injury

REV-ERBα is a nuclear receptor transcriptional repressor involved in circadian rhythm, metabolism, inflammation, and myogenesis. Antagonizing REV-ERBα has emerged as a promising therapeutic strategy, yet few compounds with favorable pharmacokinetic profiles have been identified since SR8278. Here, we report the discovery and optimization of BE2012, a 3-aminoquinazolinone antagonist identified through high-throughput screening and refined via systematic structure-activity relationship studies. BE2012 exhibited potent REV-ERBα antagonism (EC₅₀ = 0.285 μM), high nuclear receptor selectivity, minimal CNS off-target interactions, and improved ADME and pharmacokinetic properties, including a 22-fold longer half-life (<i>t</i>₁/₂ = 3.79 h) than SR8278. Molecular modeling revealed key hydrophobic and hydrogen-bonding interactions within the REV-ERBα ligand-binding pocket that stabilize BE2012 and explain its enhanced potency. In a murine model of acute muscle injury, BE2012 upregulated myogenic transcription factors and promoted muscle repair. Collectively, BE2012 represents a selective, pharmacokinetically favorable REV-ERBα/β antagonist with therapeutic potential in muscle regeneration and related diseases.