CompletedNCT03864068INSUPP-PCOSUpdated Nov 10, 2026Results posted

Inositol Supplementation to Treat PCOS (INSUPP-PCOS)

A Phase 2 interventional study of Placebo and Inositol in Polycystic Ovary Syndrome, Anovulation and Hyperandrogenism, sponsored by Milton S. Hershey Medical Center. Completed at 2 sites in United States. Open to female participants aged 18 Years to 45 Years. Per ClinicalTrials.gov, last updated 2026-11-10.

Sponsored by Milton S. Hershey Medical Center · Phase 2, Interventional, and Treatment

Updated Nov 10, 2026Results postedStudy documents posted+2 moreGo to Updates ↓

Phase: Phase 2
Study type: Interventional
Enrollment: 99
Allocation: Randomized
Ages: 18 Years to 45 Years
Sex: Female

Study summary

To determine if Inositol, a dietary supplement, will improve ovarian and adrenal androgen excess in women with Polycystic Ovarian Syndrome(PCOS).

Read the detailed 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.

Conditions studied

Polycystic Ovary Syndrome
Anovulation
Hyperandrogenism
Insulin Resistance
Glucose Intolerance
Metabolic Complication

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Keywords

Polycystic Ovary Syndrome
Anovulation
Hyperandrogenism
Insulin Resistance
Glucose Intolerance
Metabolic Complication

In context

Polycystic Ovary Syndrome

956 studies on the registry are indexed under Polycystic Ovary Syndrome; 176 are open to participants now.

This study's enrollment of 99 is above the median of 70 across 697 interventional studies indexed under Polycystic Ovary Syndrome.

Browse Polycystic Ovary Syndrome studies →

Lead sponsor

Milton S. Hershey Medical Center is the lead sponsor of 492 studies on the registry; 60 are open to participants now.

Of its 58 completed or terminated interventional studies of FDA-regulated products, 46 (79%) have results posted.

Browse Milton S. Hershey Medical Center studies →

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years to 45 Years
Sexes eligible: Female
Accepts healthy volunteers: No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

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

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 or other medications for type 2 diabetes
Women with medical conditions that are to OTC inositol or previous allergic reactions to the supplement or to the placebo maltodextrin or inulin.

Terms in these criteria, in plain language(2)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

Study design

Phase: Phase 2
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel assignment
Masking: Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment: 99 participants (actual)

Study arms

Placebo comparator
Placebo Treatment bid
Women with PCOS 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
Experimental
Active Treatment with Inositol 1gm/bid
Women with PCOS 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
Experimental
Active Treatment with Inositol 2 gm/bid
Women with PCOS 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
Experimental
Active Treatment with Inositol 3 gm/bid
Women with PCOS 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

Interventions

OtherPlacebo
Placebo
Also known as: maltodextrin and inulin
DrugInositol
1gm/bid, 2gm/bid or 3gm/bid of Inositol powder

What researchers measure

Primary outcomes

Total Testosterone
Total testosterone levels measured at baseline, 1 month, and 3 month visits.
Time frame: 3 months (baseline, 1 month and 3 month visits)

Secondary outcomes

SHBG
Sex hormone-binding globulin (SHBG) levels measured at baseline, 1 month, and 3 month visits.
Time frame: 3 months (baseline, 1 month and 3 month visits)
Free Androgen Index (FAI)
Free Androgen Index calculated at baseline, 1 month, and 3 month visits. FAI is calculated as (testosterone/SHBG)\*100 (after converting testosterone to the same units as SHBG)
Time frame: 3 months (baseline, 1 month and 3 month visits)
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. AUC was calculated at baseline and 3 month visit.
Time frame: 3 months (baseline and 3 month visits)
Fasting Insulin
Fasting insulin levels measured at baseline and 3 month visit.
Time frame: 3 months (baseline and 3 month visits)

Results

Posted Oct 28, 2026

Participant flow

Participant flow — Overall Study
Milestone	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid
Started	26	24	24	25
Completed	23	24	21	20
Not completed	3	0	3	5

Outcome measures

PrimaryTotal Testosterone

Total testosterone levels measured at baseline, 1 month, and 3 month visits.

Time frame:: 3 months (baseline, 1 month and 3 month visits)
Reported as:: Geometric least squares mean · ng/dL

Total Testosterone
ng/dL	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid
Baseline	38.1 (28.7 to 50.5)	40.0 (29.7 to 54.0)	25.5 (19.0 to 34.3)	33.8 (25.4 to 45.2)
Month 1	29.0 (21.7 to 38.8)	29.4 (21.7 to 39.8)	23.0 (16.9 to 31.3)	28.0 (20.6 to 38.1)
Month 3	42.5 (31.7 to 56.9)	35.5 (26.3 to 48.0)	29.2 (21.5 to 39.7)	30.1 (22.1 to 40.9)

SecondarySHBG

Sex hormone-binding globulin (SHBG) levels measured at baseline, 1 month, and 3 month visits.

Time frame:: 3 months (baseline, 1 month and 3 month visits)
Reported as:: Least squares mean · nmol/L

SHBG
nmol/L	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid
Baseline	36.1 (29.0 to 42.2)	41.3 (34.8 to 47.8)	38.1 (31.6 to 44.6)	37.1 (30.8 to 43.4)
Month 1	38.0 (31.2 to 44.9)	41.5 (34.3 to 48.7)	33.8 (26.6 to 41.0)	39.3 (32.2 to 46.5)
Month 3	37.3 (30.8 to 43.9)	41.1 (34.3 to 47.9)	36.3 (29.4 to 43.2)	37.8 (30.9 to 44.7)

SecondaryFree Androgen Index (FAI)

Free Androgen Index calculated at baseline, 1 month, and 3 month visits. FAI is calculated as (testosterone/SHBG)\*100 (after converting testosterone to the same units as SHBG)

Time frame:: 3 months (baseline, 1 month and 3 month visits)
Reported as:: Geometric least squares mean · ratio (unitless)

Free Androgen Index (FAI)
ratio (unitless)	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid
Baseline	4.0 (2.8 to 5.6)	3.7 (2.6 to 5.3)	2.7 (1.9 to 3.8)	3.4 (2.4 to 4.9)
Month 1	2.9 (2.0 to 4.3)	2.8 (1.8 to 4.1)	3.1 (2.0 to 4.6)	2.7 (1.8 to 4.1)
Month 3	4.4 (3.1 to 6.3)	3.3 (2.3 to 4.7)	3.3 (2.2 to 4.7)	3.0 (2.1 to 4.4)

SecondaryArea 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. AUC was calculated at baseline and 3 month visit.

Time frame:: 3 months (baseline and 3 month visits)
Reported as:: Least squares mean · mg/dl*hour

Area Under the Curve (AUC) of Glucose
mg/dl*hour	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid
Baseline	261.7 (237.5 to 285.8)	247.8 (222.4 to 273.2)	245.4 (220.2 to 270.6)	264.5 (240.0 to 289.1)
Month 3	260.6 (235.2 to 285.9)	246.7 (220.6 to 272.9)	250.4 (223.7 to 277.1)	266.5 (239.8 to 293.2)

SecondaryFasting Insulin

Fasting insulin levels measured at baseline and 3 month visit.

Time frame:: 3 months (baseline and 3 month visits)
Reported as:: Geometric least squares mean · uIU/mL

Fasting Insulin
uIU/mL	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid
Baseline	8.0 (5.6 to 11.4)	8.5 (5.8 to 12.3)	6.5 (4.5 to 9.5)	6.4 (4.5 to 9.3)
Month 3	7.9 (5.5 to 11.3)	6.9 (4.8 to 9.9)	6.7 (4.6 to 9.7)	6.4 (4.4 to 9.2)

Adverse events

Collected over Adverse events collected at 1 month and 3 month study visits. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
Group	Deaths	Serious	Other
Placebo Treatment Bid	0/26 (0%)	0/26 (0%)	16/26 (61.5%)
Active Treatment With Inositol 1gm/Bid	0/24 (0%)	0/24 (0%)	18/24 (75%)
Active Treatment With Inositol 2 gm/Bid	0/24 (0%)	0/24 (0%)	14/24 (58.3%)
Active Treatment With Inositol 3 gm/Bid	0/25 (0%)	0/25 (0%)	13/25 (52%)

Most frequent other events

Showing 10 of 12

Most frequent other events
Event	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid
DiarrheaGastrointestinal disorders	2/26	6/24	3/24	4/25
Abdominal PainGastrointestinal disorders	2/26	3/24	5/24	1/25
HeadacheNervous system disorders	3/26	5/24	5/24	2/25
NauseaGastrointestinal disorders	5/26	1/24	0/24	1/25
DysmenorrheaReproductive system and breast disorders	2/26	4/24	1/24	3/25
Upper respiratory infectionRespiratory, thoracic and mediastinal disorders	3/26	2/24	3/24	2/25
AcneSkin and subcutaneous tissue disorders	1/26	3/24	1/24	0/25
DyspepsiaGastrointestinal disorders	1/26	2/24	0/24	1/25
VomitingGastrointestinal disorders	0/26	1/24	2/24	1/25
Vaccination side effectsGeneral disorders	0/26	1/24	2/24	1/25

Baseline characteristics

Age, Continuous
Age, Continuous(years)	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid	Total
Mean	29.8 ± 5.8	30.3 ± 5.7	29.1 ± 7.0	30.0 ± 5.5	29.8 ± 5.9

Sex: Female, Male
Sex: Female, Male(Participants)	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid	Total
Female	26	24	24	25	99
Male	0	0	0	0	0

Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid	Total
Hispanic or Latino	5	2	2	0	9
Not Hispanic or Latino	21	22	22	25	90
Unknown or Not Reported	0	0	0	0	0

Race (NIH/OMB)
Race (NIH/OMB)(Participants)	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid	Total
American Indian or Alaska Native	0	0	0	0	0
Asian	2	1	2	0	5
Native Hawaiian or Other Pacific Islander	0	0	0	0	0
Black or African American	4	3	3	3	13
White	20	19	18	20	77
More than one race	0	0	1	2	3
Unknown or Not Reported	0	1	0	0	1

BMI status
BMI status(Participants)	Placebo Treatment Bid	Active Treatment With Inositol 1gm/Bid	Active Treatment With Inositol 2 gm/Bid	Active Treatment With Inositol 3 gm/Bid	Total
<30 kg/m2	8	8	7	9	32
>=30 kg/m2	18	16	17	16	67

Study locations

2 sites

Penn State College of Medicine, Penn State Milton S. Hershey Medical Center
Hershey, Pennsylvania 17033, United States
University of Pennsylvania
Philadelphia, Pennsylvania 19104, United States

References and documents

Study documents

Protocol, analysis plan and consent form ↗ · Feb 16, 2026

PDFs hosted by the registry, ClinicalTrials.gov.

Updates

2 registry updates since Sep 25, 2026

Results

Results posted

posted Oct 28, 2026

Enrollment

154→99

Nov 10, 2026

Primary outcomes

1 edited

What changed in the outcomes

Edited~~Change in total testosterone~~Total TestosteroneTime frame: ~~baseline and 3 months~~ → 3 months (baseline, 1 month and 3 month visits)

Oct 28, 2026

Documents

Protocol, analysis plan and consent form ↗ posted

Oct 28, 2026

Secondary outcomes

4 edited

What changed in the outcomes

Edited~~Change in~~ SHBGTime frame: ~~baseline and 3 months~~ → 3 months (baseline, 1 month and 3 month visits)
Edited~~Change in~~ Free Androgen Index (FAI)Time frame: ~~baseline and 3 months~~ → 3 months (baseline, 1 month and 3 month visits)
Edited~~Change in area under~~Area Under the ~~curve~~Curve (AUC) of ~~glucose~~GlucoseTime frame: ~~baseline and 3 months~~ → 3 months (baseline and 3 month visits)
Edited~~Change in fasting insulin~~Fasting InsulinTime frame: ~~baseline and 3 months~~ → 3 months (baseline and 3 month visits)

Oct 28, 2026

Show all 2 updates

Nov 10, 2026
Enrollment 154→99
Oct 28, 2026
Results posted
Documents Protocol, analysis plan and consent form ↗ posted
Primary outcomes 1 edited
What changed in the outcomes
- Edited~~Change in total testosterone~~Total TestosteroneTime frame: ~~baseline and 3 months~~ → 3 months (baseline, 1 month and 3 month visits)
Secondary outcomes 4 edited
What changed in the outcomes
- Edited~~Change in~~ SHBGTime frame: ~~baseline and 3 months~~ → 3 months (baseline, 1 month and 3 month visits)
- Edited~~Change in~~ Free Androgen Index (FAI)Time frame: ~~baseline and 3 months~~ → 3 months (baseline, 1 month and 3 month visits)
- Edited~~Change in area under~~Area Under the ~~curve~~Curve (AUC) of ~~glucose~~GlucoseTime frame: ~~baseline and 3 months~~ → 3 months (baseline and 3 month visits)
- Edited~~Change in fasting insulin~~Fasting InsulinTime frame: ~~baseline and 3 months~~ → 3 months (baseline and 3 month visits)
+ 2 other changes: verification date and arm descriptions

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT03864068
Lead sponsor: Milton S. Hershey Medical Center
Collaborators: National Center for Complementary and Integrative Health (NCCIH)
Responsible party: Richard S. Legro, M.D. (Chair, Obstetrics and Gynecology, Milton S. Hershey Medical Center) — Principal investigator
First posted: Mar 6, 2019
Start date: Jan 24, 2020
Primary completion: Dec 10, 2025
Completion: Dec 10, 2025
Results posted: Oct 28, 2026
Last update: Nov 10, 2026

Study contacts

Richard S. Legro, M.D.

principal investigator · Penn State College of Medicine, Hershey Medical Center

Oversight

Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

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Inositol Supplementation to Treat PCOS (INSUPP-PCOS)

Study summary

Conditions studied

Browse trials for

Keywords

In context

Polycystic Ovary Syndrome

Lead sponsor

Who can participate

✓Inclusion criteria

✕Exclusion criteria

Study design

Study arms

Interventions

What researchers measure

Primary outcomes

Secondary outcomes

Results

Participant flow

Outcome measures

Adverse events

Baseline characteristics

Study locations

References and documents

Study documents

Updates

Registry details

Key details

Study contacts

Oversight

Not currently enrolling

Follow this study

Discussion

Other studies in this condition

Other studies from this sponsor

Inclusion criteria

Exclusion criteria