Impact of Endogenous E2 on SSI and GH Rebound

  • Study type:

    Interventional What is this?

    Describes the nature of a clinical study. Types include:

    • Observational study — observes people and measures outcomes without affecting results.
    • Interventional study (clinical trial) — studies new tests, treatments, drugs, surgical procedures or devices.
    • Medical records research — uses historical information collected from medical records of large groups of people to study how diseases progress and which treatments and surgeries work best.
  • Study phase:

    I What is this?

    During the early phases (phases 1 and 2), researchers assess safety, side effects, optimal dosages and risks/benefits. In the later phase (phase 3), researchers study whether the treatment works better than the current standard therapy. They also compare the safety of the new treatment with that of current treatments. Phase 3 trials include large numbers of people to make sure that the result is valid. There are also less common very early (phase 0) and later (phase 4) phases. Phase 0 trials are small trials that help researchers decide if a new agent should be tested in a phase 1 trial. Phase 4 trials look at long-term safety and effectiveness, after a new treatment has been approved and is on the market.

Study IDs

  • Site IRB:

    • Rochester, Minnesota: 13-007623
  • NCT ID:

  • Sponsor Protocol Number:


About this study

Endogenous estrogens maintain growth hormone (GH) secretion in postmenopausal women by potentiating endogenous GH-releasing hormone (GHRH) drive and restraining somatostatin inhibition of GH release.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. If you need assistance understanding the eligibility criteria, please contact the study team.

See eligibility criteria


  1. 60 healthy post-menopausal women (ages 55 to 80 y);
  2. BMI 18-30 kg/m2
  3. Community dwelling; and voluntarily consenting


  1. Recent use of psychotropic or neuroactive drugs (within five biological half-lives);
  2. Obesity (outside weight range above);
  3. Laboratory test results not deemed physician acceptable, cholesterol >250, triglycerides > 300, BUN >30 or creatinine > 1.5 mg/dL, liver function tests exceeding twice upper limit of normal, electrolyte abnormality, anemia;
  4. Drug or alcohol abuse, psychosis, depression, mania or severe anxiety;
  5. Systemic inflammatory disease;
  6. Endocrinopathy, other than primary thyroidal failure receiving replacement;
  7. Nightshift work or recent transmeridian travel (exceeding 3 time zones within 7 days of CRU admission);
  8. Acute weight change (loss or gain of > 2 kg in 6 weeks);
  9. Systemic illness
  10. Unwillingness to provide written informed consent.
  11. Allergy to anastrozole or fulvestrant (treatment drugs).
  12. History or suspicion of breast cancer.
  13. History of carcinoma (excluding localized basal cell carcinoma removed or surgically treated with no recurrence).
  14. History of thrombotic arterial disease (stroke, TIA, MI, angina) or deep-vein thrombophlebitis.
  15. History of CHF, cardiac arrhythmias, congenital QT prolongation, and medications used to treat cardiac arrhythmias.
  16. Pre-menopausal status as determined by screening hormone measurements.

Participating Mayo Clinic locations

Study statuses change often. Please contact us for help.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Johannes Veldhuis, M.D.

Contact us for the latest status

Jean Wigham R.N.