MR-L22

MR-L22 is an orally active, first-in-class small molecule allosteric activator of long-form phosphodiesterase 4 (PDE4) enzymes (LoAc). Developed by Mironid, MR-L22 is designed to target elevated cyclic adenosine monophosphate (cAMP) signaling, which drives cystogenesis, cell proliferation, and fluid secretion in Autosomal Dominant Polycystic Kidney Disease (ADPKD). By selectively binding to the amino-terminal regulatory domains (UCR1 and UCR2) of long PDE4 isoforms, MR-L22 enhances cAMP hydrolysis and lowers intracellular cAMP levels. In preclinical models of ADPKD, MR-L22 has demonstrated significant efficacy in reducing total kidney volume, suppressing cystic burden, and preserving renal function, while showing a differentiated safety profile with fewer aquaretic side effects compared to the vasopressin V2 receptor antagonist tolvaptan.

Other names

LoAc compound MR-L22