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Soy Estrogen Alternative Study (SEA)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00000612
Recruitment Status : Completed
First Posted : October 28, 1999
Last Update Posted : May 13, 2016
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)

Tracking Information
First Submitted Date  ICMJE October 27, 1999
First Posted Date  ICMJE October 28, 1999
Last Update Posted Date May 13, 2016
Study Start Date  ICMJE January 1996
Primary Completion Date Not Provided
Current Primary Outcome Measures  ICMJE Not Provided
Original Primary Outcome Measures  ICMJE Not Provided
Change History
Current Secondary Outcome Measures  ICMJE Not Provided
Original Secondary Outcome Measures  ICMJE Not Provided
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title  ICMJE Soy Estrogen Alternative Study (SEA)
Official Title  ICMJE Not Provided
Brief Summary To conduct a three-armed trial assessing the effect of soy phytoestrogens on menopausal complaints, plasma lipids and lipoproteins, vaginal bleeding and endometrial proliferation, and health related quality of life.
Detailed Description


The results of many studies indicate that estrogen replacement therapy (ERT) reduces the risk of coronary heart disease (CHD) in postmenopausal women. However, less than 9 percent of these women choose to take ERT because of unwanted side effects and concerns about increased risk of cancer associated with ERT. Therefore, alternative therapies are needed.

The isoflavonoids found in soy protein (specifically genistein) have many properties that may reduce the risk of coronary heart disease. These include favorable effects on plasma lipids and coronary artery vasomotion. Furthermore, genistein is a tyrosine kinase (TK) inhibitor with inhibitory effects on thrombin activity and TK receptor-linked mitogens that may be associated with atherogenesis and neointimal formation after angioplasty.


Randomized, double-blind, placebo-controlled. The women were randomized into one of three groups: placebo, conjugated equine estrogens, or soy supplementation. Primary endpoints were the impact on menopausal complaints such as hot flushes, mood lability, anxiety, sleep disturbances; effects on plasma lipids and lipoproteins, including lipoprotein (a); effects on vaginal bleeding and endometrial proliferation; changes in health-related quality of life. Secondary endpoints included: assessment of the impact of these interventions on the progression of carotid artery intimal medial wall thickening as assessed by B-mode ultrasonography; bone density and bone turnover; additional measures to monitor the compliance and safety of the intervention such as mammography, anticipated or known side effects of hormone replacement therapy, blood levels of genistein, and clinical outcomes such as hospitalizations, physician visits, and symptoms. The study ended in December, 1998.

The study was a subproject within a program project on coronary atherosclerosis in females, primarily monkeys. Dr. Thomas B. Clarkson was the P.I. The subproject dollars were estimated based on the CRISP dollars assigned to the study which were approximately 12 percent of the total program project dollars and were broken down as follows: FY 1996 - 219,254; FY 1997 - $217,000; FY 1998 - $221,000.

The study completion date listed in this record was obtained from the "End Date" entered in the Protocol Registration and Results System (PRS) record.

Study Type  ICMJE Interventional
Study Phase  ICMJE Phase 2
Study Design  ICMJE Allocation: Randomized
Masking: Double
Primary Purpose: Prevention
Condition  ICMJE
  • Cardiovascular Diseases
  • Endometrial Hyperplasia
  • Heart Diseases
  • Menopausal Complaints
  • Uterine Diseases
  • Menopause
Intervention  ICMJE
  • Drug: estrogens, conjugated
  • Behavioral: diet, soy proteins
  • Behavioral: dietary supplements
Study Arms  ICMJE Not Provided
Publications * Clarkson TB, Anthony MS, Williams JK, Honoré EK, Cline JM. The potential of soybean phytoestrogens for postmenopausal hormone replacement therapy. Proc Soc Exp Biol Med. 1998 Mar;217(3):365-8.

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status  ICMJE Completed
Enrollment  ICMJE Not Provided
Original Enrollment  ICMJE Not Provided
Actual Study Completion Date  ICMJE December 1998
Primary Completion Date Not Provided
Eligibility Criteria  ICMJE Perimenopausal/menopausal women, ages 45 to 55.
Sex/Gender  ICMJE
Sexes Eligible for Study: Female
Ages  ICMJE 45 Years to 55 Years   (Adult)
Accepts Healthy Volunteers  ICMJE No
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE Not Provided
Removed Location Countries  
Administrative Information
NCT Number  ICMJE NCT00000612
Other Study ID Numbers  ICMJE 115
P01HL045666 ( U.S. NIH Grant/Contract )
Has Data Monitoring Committee Not Provided
U.S. FDA-regulated Product Not Provided
IPD Sharing Statement  ICMJE Not Provided
Responsible Party Not Provided
Study Sponsor  ICMJE National Heart, Lung, and Blood Institute (NHLBI)
Collaborators  ICMJE Not Provided
Investigators  ICMJE Not Provided
PRS Account National Heart, Lung, and Blood Institute (NHLBI)
Verification Date November 2000

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP