Pharmaceutisch Weekblad

, Volume 10, Issue 1, pp 22–25 | Cite as

The bioavailability of Tamoplex® (tamoxifen)

Part 3. A steady-state study in breast cancer patients
  • P. H. Th. J. Slee
  • D. De Vos
  • D. Chapman
  • D. Stevenson
Short Communications


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 andN-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 andN-desmethyltamoxifen, their ratio appeared to be constant in the individual patient.

Key words

Bioavailability Breast neoplasms Drug evaluation Tamoxifen 


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Copyright information

© Bohn, Scheltema & Holkema 1988

Authors and Affiliations

  • P. H. Th. J. Slee
    • 1
  • D. De Vos
    • 2
  • D. Chapman
    • 3
  • D. Stevenson
    • 3
  1. 1.Department of Clinical OncologySint Jozef ZiekenhuisAH Goudathe Netherlands
  2. 2.Medical DepartmentPharmachemie BVRN Haarlemthe Netherlands
  3. 3.The Robens InstituteUniversity of SurreyGuildfordUK

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