Mevinic acid is reversible competitive inhibitors of HMG-CoA reductase (Ki in the range of 0.2-1 nM). Mevinic acid is a precursor of a Mevastatin (mevinic acid lactone) -- a hypolipidemic agent that belongs to the statins class. Mevastatin inactive until metabolized in the liver to the open-ring hydroxy acid (Mevinic acid). Mevastatin might be considered the first statin drug; clinical trials on mevastatin were performed in the late 1970s in Japan, but it was never marketed.