N-Desmethyltamoxifen (developmental code name ICI-55,548) is a major
metabolite of
tamoxifen, a
selective estrogen receptor modulator (SERM).[1][2]N-Desmethyltamoxifen is further
metabolized into
endoxifen (4-hydroxy-N-desmethyltamoxifen), which is thought to be the major active form of tamoxifen in the body.[1][2][3] In one study, N-desmethyltamoxifen had an
affinity for the
estrogen receptor of 2.4% relative to
estradiol.[4] For comparison, tamoxifen, endoxifen, and
afimoxifene (4-hydroxytamoxifen) had relative binding affinities of 2.8%, 181%, and 181%, respectively.[4]
^Binkhorst L, Mathijssen RH, Jager A, van Gelder T (March 2015). "Individualization of tamoxifen therapy: much more than just CYP2D6 genotyping". Cancer Treat Rev. 41 (3): 289–99.
doi:
10.1016/j.ctrv.2015.01.002.
PMID25618289.
N-Desmethyltamoxifen (developmental code name ICI-55,548) is a major
metabolite of
tamoxifen, a
selective estrogen receptor modulator (SERM).[1][2]N-Desmethyltamoxifen is further
metabolized into
endoxifen (4-hydroxy-N-desmethyltamoxifen), which is thought to be the major active form of tamoxifen in the body.[1][2][3] In one study, N-desmethyltamoxifen had an
affinity for the
estrogen receptor of 2.4% relative to
estradiol.[4] For comparison, tamoxifen, endoxifen, and
afimoxifene (4-hydroxytamoxifen) had relative binding affinities of 2.8%, 181%, and 181%, respectively.[4]
^Binkhorst L, Mathijssen RH, Jager A, van Gelder T (March 2015). "Individualization of tamoxifen therapy: much more than just CYP2D6 genotyping". Cancer Treat Rev. 41 (3): 289–99.
doi:
10.1016/j.ctrv.2015.01.002.
PMID25618289.