Introduction to toremifene.
Toremifene, a triphenylethylene antiestrogen first synthesized in 1981, binds to the estrogen receptor with an affinity about 5% that of estradiol. Its antiestrogenicity/estrogenicity ratio in animal models is about 5 times that of tamoxifen, though it requires somewhat higher doses for full effectiveness, and it is active against breast cancer in animal and cell culture models. It has a long elimination half-life and there are several metabolites, but the principal antitumor activity appears to be due to the unchanged drug. In Phase I and Phase II clinical trials, toremifene has shown good response rates in ER-positive or ER-unknown tumors, and significant responses after failure of tamoxifen or other hormonal or chemotherapeutic regimens, with rare and mild side effects.
Kangas
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Farmos Group, Research Center, Turku, Finland.
D000230:Adenocarcinoma / Q000188:drug therapy; D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy; D004965:Estrogen Antagonists / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy; D051381:Rats; D013629:Tamoxifen / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D017312:Toremifene
D000970:Antineoplastic Agents; D004965:Estrogen Antagonists; D013629:Tamoxifen; D017312:Toremifene