Inositol Supplementation to Treat PCOS (INSUPP-PCOS)

Recruitment Status
COMPLETED
(See Contacts and Locations)Verified December 2025 by Milton S. Hershey Medical Center
Sponsor
Milton S. Hershey Medical Center
Information Provided by (Responsible Party)
Richard S. Legro, M.D.
Clinicaltrials.gov Identifier
NCT03864068
Other Study ID Numbers:
Study00010252
First Submitted
March 3, 2019
First Posted
March 5, 2019
Last Update Posted
January 6, 2026
Last Verified
December 2025

ClinicalTrials.gov processed this data on January 2026. Link to the current ClinicalTrials.gov record .

History of Changes

Study Details

Study Description

This trial will test prospectively the effects of inositol supplementation in a dose ranging double blind randomized controlled trial, according to CONSORT guidelines. This will be a four armed study of three doses of inositol vs. placebo over a three month period with the reduction in hyperandrogenism (based on serum testosterone levels) as the primary outcome and key secondary outcomes of the change in sex hormone binding globulin(SHBG) and the related free androgen index, fasting insulin levels and area under the curve glucose levels from an oral glucose challenge test (OGTT). The hypothesis is that women with PCOS who receive inositol supplementation will have a dose related reduction in hyperandrogenism. Further, we propose that the primary mechanism of inositol will be a significant improvement in hyperandrogenism (both ovarian and adrenal) vs. placebo, as documented by a lower free androgen index \[decreased total testosterone and increased sex hormone blinding globulin (SHBG)\], lower sebum measures and lower antral follicle counts of the ovary and anti-Mullerian hormone, all of which will correlate with the decrease in hyperandrogenism.

Condition or DiseaseIntervention/Treatment
Polycystic Ovary SyndromeAnovulationHyperandrogenismInsulin ResistanceGlucose IntoleranceMetabolic Complication
Other: PlaceboDrug: InositolDrug: InositolDrug: Inositol

Study Design

Study TypeInterventional
Actual Enrollment154 participants
Design AllocationRandomized
Interventional ModelParallel Assignment
MaskingQuadruple
Primary PurposeTreatment
Official TitleInositol Supplementation to Treat Polycystic Ovary Syndrome: A Double Blind Dose Ranging RCT (INSUPP-PCOS)
Study Start DateJanuary 23, 2020
Actual Primary Completion DateDecember 9, 2025
Actual Study Completion DateDecember 9, 2025

Groups and Cohorts

Group/CohortIntervention/Treatment
Placebo Treatment bid
Women with PCOS (N = 30) will receive the daily placebo (maltodextrin and inulin) in an identical fashion as the active study group and will be monitored the same.
Other: Placebo
Placebo
Active Treatment with Inositol 1gm/bid
Women with PCOS (N = 30) will receive daily inositol powder BID as active drug (each dose with 1000 mg of myo-inositol and 25 mg of d-chiro-inositol) over the initial 3 mos RCT period.
Drug: Inositol
1gm/bid, 2gm/bid or 3gm/bid of Inositol powder
Active Treatment with Inositol 2 gm/bid
Women with PCOS (N = 30) will receive daily inositol powder BID as active drug (each dose with 2000 mg of myo-inositol and 50 mg of d-chiro-inositol) over the initial 3 mos RCT period.
Drug: Inositol
1gm/bid, 2gm/bid or 3gm/bid of Inositol powder
Active Treatment with Inositol 3 gm/bid
Women with PCOS (N = 30) will receive daily inositol powder BID as active drug (each dose with 3000 mg of myo-inositol and 75 mg of d-chiro-inositol) over the initial 3 mos RCT period.
Drug: Inositol
1gm/bid, 2gm/bid or 3gm/bid of Inositol powder

Outcome Measures

Primary Outcome Measures
  1. Change in total testosterone
    Serum total testosterone levels
Secondary Outcome Measures
  1. Change in SHBG
    SHBG levels
  2. Change in Free Androgen Index (FAI)
    FAI levels
  3. Change in area under the curve (AUC) of glucose
    AUC of a 2-hour 75g glucose tolerance test, which measures glucose at 0, 30, 60, 90, and 120 minutes.
  4. Change in fasting insulin
    Fasting insulin levels

Eligibility Criteria

Ages Eligible for Study(Adult)
Sexes Eligible for StudyFemale
Accepts Healthy VolunteersNo
Inclusion Criteria
Women with chronic anovulation or oligomenorrhea defined as spontaneous intermenstrual periods of greater than or equal to 45 days or a total of less than or equal to 8 menses per year.
Women with Hyperandrogenism defined as a total testosterone greater than 50 ng/dL or a free androgen index greater than 10.
Women with Polycystic Ovaries on Ultrasound defined as either 12 or more follicles measuring 2-9 mm in diameter or increased ovarian volume greater than 10 cm.
Exclusion Criteria
Women with Hyperprolactinemia defined as 2 prolactin levels at least one week apart greater than 30 ng/mL.
Women with known 21-hydroxylase deficiency or other enzyme deficiency leading to the congenital adrenal hyperplasia.
Women with elevated FSH levels greater than 10 mIU/mL.
Women with uncorrected thyroid disease as per ASRM guidelines for nonpregnant subjects (TSH less than 0.45 mIU/mL or greater than 4.5 MIU/mL).
Women with a suspected adrenal or ovarian tumor secreting androgens
Women with Cushing's syndrome
Women on confounding medications which affect ovarian function including metformin, hormonal contraceptives or other medications for type 2 diabetes
Women with medical conditions that are contraindications to OTC inositol or previous allergic reactions to the supplement or to the placebo maltodextrin or inulin.

Contacts and Locations

Sponsors and CollaboratorsMilton S. Hershey Medical Center
Locations
Penn State College of Medicine, Penn State Milton S. Hershey Medical Center | Hershey Pennsylvania, United States, 17033University of Pennsylvania | Philadelphia Pennsylvania, United States, 19104
Investigators
Principal Investigator: Richard S. Legro, M.D., Penn State College of Medicine, Hershey Medical Center