title: The bioavailability of Tamoplex (tamoxifen). Part 3. A steady-state study in breast cancer patients.
abstract: The bioavailability of two tamoxifen preparations (Tamoplex and Nolvadex) was compared in a multiple dose two-way cross-over design in twelve breast cancer patients. The formulations were found to be bioequivalent. Mean steady-state serum levels of tamoxifen and N-desmethyltamoxifen were 133 ng/ml and 242 ng/ml, respectively, at a single daily dose of three tablets of Tamoplex 10 mg and 128 ng/ml and 248 ng/ml, respectively, at a single daily dose of three tablets of Nolvadex 10 mg. While there was a large interpatient as well as intrapatient variability in steady-state levels of tamoxifen and N-desmethyltamoxifen, their ratio appeared to be constant in the individual patient.
authors.affiliation: Department of Clinical, Oncology, Sint Jozef Ziekenhuis, Gouda, the Netherlands.
authors.forename: P H
authors.initials: PH
authors.lastname: Slee
authors.forename: D
authors.initials: D
authors.lastname: De Vos
authors.forename: D
authors.initials: D
authors.lastname: Chapman
authors.forename: D
authors.initials: D
authors.lastname: Stevenson
mesh_terms: D000328:Adult; D000368:Aged; D001682:Biological Availability; D001943:Breast Neoplasms / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008875:Middle Aged; D013629:Tamoxifen / Q000031:analogs & derivatives / Q000493:pharmacokinetics*
chemical_list: D013629:Tamoxifen; C028787:N-desmethyltamoxifen