S-methyl-KE-298 is the second main metabolite in plasma,is a methyl conjugate of deacetyl-KE-298.KE-298 inhibits matrix metalloproteinase (MMP-1) production from rheumatoid arthritis (RA) synovial cells.
In vitro protein binding of S-methyl-KE-298 is high in rat (>97%), dog (>89%) and human plasma (>99%), respectively[2].