mk 791

Cilastatin (MK-0791) is a potent, reversible, competitive inhibitor of renal dehydropeptidase I (DHP-I), exhibiting an IC₅₀ of 0.1 μM. By inhibiting DHP-I in the kidney, Cilastatin prevents the enzymatic degradation of β-lactam antibiotics, thereby enhancing their stability and therapeutic efficacy. In addition, Cilastatin demonstrates inhibitory activity against the bacterial metallo-β-lactamase enzyme CphA, with an IC₅₀ of 178 μM. Clinically and experimentally, Cilastatin is widely used as an antibacterial adjunct to improve antibiotic performance and reduce renal metabolism of co-administered β-lactam drugs.

MK-789 is an inhibitor of dehydropeptidase I. MK-789 and MK-791 alter the renal excretion of N-formimidoyl thienamycin from glomerular filtration plus tubular secretion to glomerular filtration only, possibly by competitively inhibiting the penetration of