What is "afimoxifene"

n. A selective estrogen receptor modulator which is the active metabolite of tamoxifen.

Afimoxifene, also known as 4-hydroxytamoxifen (4-OHT, 4-HT, OHTAM, others), is a selective estrogen receptor modulator which is the active metabolite of tamoxifen. Afimoxifene is a transdermal gel formulation and is being developed by Ascend Therapeutics, Inc. under the trademark TamoGel.

Afimoxifene has completed a phase II clinical trial for the treatment of cyclical mastalgia.

A study in France on 55 women showed that rubbing afimoxifene on the skin was as good as tamoxifen tablets at slowing breast cancer growth. A US trial will compare 6 weeks use before breast cancer surgery. Skin application can reduce systemic levels by a factor of nine and this is expected to reduce the unpleasant side-effects of tamoxifen.