Phosphoramidon disodium, a microbial metabolite, is a specific metalloprotease thermolysin inhibitor with an IC50 of 0.4 µg/mL. Phosphoramidon disodium also inhibits endothelin-converting enzyme (ECE), neutral endopeptidase (NEP), and angiotensin-converting enzyme (ACE) with IC50 values of 3.5, 0.034, and 78 µM, respectively[1][2][3].