Ladder Bio

Ladder Bio is a private, preclinical biotechnology company developing Spiroligomers™, a novel class of ladder-shaped, peptide-like synthetic molecules for therapeutics and diagnostics. The company says its platform is designed to combine biologic-like binding specificity with the stability, cell permeability, oral bioavailability potential, and manufacturability more commonly associated with small molecules. Ladder Bio is using structure-guided chemistry, computational design, and very large compound libraries, including DNA-encoded libraries, to discover binders against difficult protein targets. The company appears to be focused primarily on therapeutic applications, while also highlighting diagnostic and biosecurity uses of its chemistry. Formerly known as ThirdLaw Molecular, it rebranded to Ladder Bio in November 2025 and has raised seed financing to advance lead programs and platform scale-up.