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Safety and Effectiveness of Soy Phytoestrogens to Prevent Bone Loss (OPUS)

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ClinicalTrials.gov Identifier: NCT00665860
Recruitment Status : Completed
First Posted : April 24, 2008
Last Update Posted : April 24, 2008
Information provided by:

Study Description
Brief Summary:
The purpose of this study is to determine whether soy isoflavone supplementation is safe and effective to prevent bone loss in postmenopausal women.

Condition or disease Intervention/treatment
Osteoporosis Dietary Supplement: Placebo Dietary Supplement: Soy isoflavones

Detailed Description:
Over-the-counter soy isoflavone supplement usage is becoming common among postmenopausal women. However, there is no documented scientific evidence of its long-term safety and efficacy in preventing osteoporosis. Our primary goal is to determine the safety, efficacy, and optimal dosage of isoflavone supplementation to reduce bone loss in postmenopausal women. The multi-state, multi-institutional design ensures that the study results are representative of postmenopausal women in the U.S. population. Confirming the skeletal benefits of soy isoflavones could translate into reduced healthcare costs related to osteoporosis.

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 403 participants
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Official Title: Safety, Efficacy, and Optimal Dosage of Soy Isoflavones to Prevent Osteoporosis
Study Start Date : April 2001
Primary Completion Date : June 2006
Study Completion Date : June 2006

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Osteoporosis
U.S. FDA Resources

Arms and Interventions

Arm Intervention/treatment
Placebo Comparator: 1
Dietary Supplement: Placebo
Three pills per day for two years
Active Comparator: 2 Dietary Supplement: Soy isoflavones
Three pills that delivered 80 mg of aglycone isoflavones per day for two years
Other Name: Soy germ isoflavones
Active Comparator: 3 Dietary Supplement: Soy isoflavones
Three pills that delivered 120 mg aglycone isoflavones per day for two years
Other Name: Soy germ isoflavones

Outcome Measures

Primary Outcome Measures :
  1. Bone mineral density [ Time Frame: One year and two years ]

Secondary Outcome Measures :
  1. Blood biochemical bone markers (osteocalcin, bone-specific alkaline phosphatase, cross-linked N-telopeptides of type 1 collagen) [ Time Frame: One year and two years ]

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   40 Years to 60 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Must be able to swallow the pills
  • No menses for 12 months
  • Blood follicle stimulating hormone great than 30 IU/mL
  • Lumbar spine bone mineral density t-score equal to or greater than -1.5

Exclusion Criteria:

  • Strict vegetarians
  • Current or recent smokers (within last five years)
  • Abnormal screening mammogram, Pap smear and blood chemistries
  • Clinical diagnosis of osteoporosis, spine and/or hip fracture, cancer, liver, kidney, gallbladder and heart disease
  • Clinical diagnosis of psychiatric disorder
  • Any allergic reactions to soy products
  • Current treatment with bisphosphonates, calcitonin, fluoride, corticosteroids, tamoxifen, raloxifene, HRT, premarin, farestron and letrozole
  • Current usage of black cohosh, blue cohosh, dong quai, Caltrate 600+Soy, Estroven, ginseng, Healthy Women, Natural Estrogen, Opti-Soy, PhytoFem, Probalance, Promensil, Remifemin, Rimostil and Trinovin
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00665860

United States, California
University of California
Davis, California, United States, 95616
United States, Georgia
University of Georgia
Athens, Georgia, United States, 30602
United States, Texas
Baylor College of Medicine
Houston, Texas, United States, 77030
Sponsors and Collaborators
Baylor College of Medicine
University of California
Kaiser Foundation Research Institute
University of Georgia
University of Alabama at Birmingham
Texas A&M University
Study Director: William W. Wong, Ph.D. Baylor College of Medicine
More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: William W. Wong/Project Director, Baylor College of Medicine
ClinicalTrials.gov Identifier: NCT00665860     History of Changes
Other Study ID Numbers: TEXW-2001-04550
First Posted: April 24, 2008    Key Record Dates
Last Update Posted: April 24, 2008
Last Verified: April 2008

Keywords provided by Baylor College of Medicine:
Soy isoflavones
Postmenopausal women
Effective dosage

Additional relevant MeSH terms:
Bone Diseases, Metabolic
Bone Diseases
Musculoskeletal Diseases
Metabolic Diseases