NCIt definition : A mesylate salt form of trioxifene, a nonsteroidal selective estrogen receptor modulator
(SERM). Trioxifene competitively inhibits the binding of estradiol to estrogen receptor
alpha (ER alpha), resulting in ER alpha-mediated gene expression. Clinical development
of Trioxifene has not proceeded because of lack of superior results over tamoxifen
and side effect profile. (NCI);