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Climacteric SyndromeCLARANCT06136208

Pharmacokinetic Aspects of 25-mg Estradiol Pellet in Climacteric Women

A study testing s.c 25 mg estradiol pellet in people with Climacteric Syndrome and Menopause, run by Science Valley Research Institute at 1 site in Brazil.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial summary

A single center, prospective, open-label clinical study will be conducted, to monitor serum concentration and pharmacokinetic profile after subcutaneous implantation of a 25mg-estradiol bioabsorbable implant in postmenopausal women. Read more about this study

Who is it for?
Ages 41 to 59 years, women onlyHealthy volunteers can take part
Conditions the study is for
Climacteric Syndrome, Menopause, Hypoestrogenism
What is being tested?
s.c 25 mg estradiol pellet
Type of treatment
Injection or infusion
How many people
20 participants
Where
1 siteBrazil
Study dates
13 Dec 2023to 30 Jul 2025
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 41 to 59 years
  • Women only
  • Healthy volunteers accepted
  • Adult

Who may be able to join

  • Signed Informed Consent Form
  • Woman aged ≥ 41 and ≤ 59 years
  • Weight ≥ 50 kg and ≤ 98 kg
  • BMI ≥ 18.5 and ≤ 34.9 kg/m²
  • Hysterectomy (with or without oophorectomy)
  • Serum total estradiol concentration ≤ 50 pg/mL and serum FSH concentration ≥ 25 mIU/mL, both determined by immunoassays
Show all 9Show fewer
  • Presence of menopause-associated symptoms
  • Absence of signs and symptoms and propedeutics suggestive of breast cancer evidenced by mammography report (woman aged > 40 years) for less than 12 months = BI-RADS1 or BI-RADS2
  • Agreement not to use other hormones (estrogens, androgens and/or progestogens) in any pharmaceutical form during the study

Who cannot join

  • Contraindications to the use of menopausal hormone therapy: Bleeding vaginal of unknown cause; personal history of hormone-dependent neoplasm including breast cancer, precursor lesions of breast cancer; liver disease; porphyria; personal history of coronary artery disease, cerebrovascular and venous thromboembolism; systemic lupus erythematosus with high thromboembolic risk and meningioma
  • Comorbidities associated with increased cardiovascular risk: smoking, uncontrolled diabetes, dyslipidemia, and uncontrolled hypertension
  • Serious chronic disorders, including metastatic malignancies, kidney disease in the end-stage with or without dialysis, clinically unstable heart disease, or any another disorder that, in the opinion of the investigator, excludes the participant from the study
  • Immunocompromise or suspected or confirmed diagnosis of immunodeficiency based on history and/or physical or laboratory examination
  • Active liver disease or dysfunction
  • Benign or malignant tumors of the liver
Show all 12Show fewer
  • Clinical diagnosis of polycystic ovary syndrome
  • Use of other hormones (estrogens, androgens and/or progestogens) in any pharmaceutical form in the last month
  • Current use of drugs that alter cytochrome P450 and metabolization of Estrogens
  • Current use of tamoxifen, aromatase inhibitors, or agonists/antagonists GnRH for cancer or any other condition
  • Current use of phytoestrogens
  • Participation in another clinical study within 30 days prior to the start of the Study treatment

Trial locations and contacts

1 site in 1 country.

Brazil1 site

  • Irmandade Da Santa Casa De Misericórdia De Santos - Science Valley Research Center

    Santos, São Paulo, 11075-900

Other trials in Brazil

About this study

Official title: Pharmacokinetic Aspects of 25-mg Estradiol Pellet in Climacteric Women Comprehensive Longitudinal Assessment of Release With Estradiol Pellet Analysis (CLARA Study)

A single center, prospective, open-label clinical study will be conducted, to monitor serum concentration and pharmacokinetic profile after subcutaneous implantation of a 25mg-estradiol bioabsorbable implant in postmenopausal women.

Read the detailed description

Assessing serum total estradiol concentration and determination of pharmacokinetic parameters will be performed in participants eligible for the study before and after the insertion of estradiol pellet (25 mg) at different collection times [in the first 24 hours, weekly in the first month and monthly until 6 months are complete]. Additionally, the concentration of other hormones influenced by the action of estradiol will be determined (total testosterone, estrone, FSH, LH, SHBG, and prolactin). Medical visits will be carried out for clinical evaluation and follow-up of the participants in the baseline and after 1 month, 3 months, and 6 months. Assessment of the primary outcome will be performed 6 months after estradiol pellet insertion. N=20 participants.

Being tested
s.c 25 mg estradiol pellet
Keywords
Climateric, Estradiol Pellet, Menopause, Pharmacokinectic

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • s.c 25 mg estradiol pelletDrug

    Subcutaneous insertion of 25 mg estradiol pellet.

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Serum total estradiol concentration

    Multiple blood sample will be collected before pellet implantation and 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days , 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days and will be determined by liquid chromatography (LC-MS/MS)

    Measured: 0, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days , 21 days , 28 days , 56 days, 84 days, 112 days, 140 days and 168 days

  2. Area under the curve (AUC(0 ∞))

    Multiple blood sample will be collected before pellet implantation and 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days , 21 days, 28 days, 56 days, 84 days ,112 days ,140 days and 168 days and will be determined by liquid chromatography (LC-MS/MS)

    Measured: 0, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days

  3. Maximum concentration (Cmax)

    Multiple blood sample will be collected before pellet implantation and 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days and will be determined by liquid chromatography (LC-MS/MS)

    Measured: 0, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days

  4. Time to reach maximum concentration (tmax)

    Multiple blood sample will be collected before pellet implantation and 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days and will be determined by liquid chromatography (LC-MS/MS)

    Measured: 0, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days

  5. Half Life (t1/2)

    Multiple blood sample will be collected before pellet implantation and 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 dyas, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days and will be determined by liquid chromatography (LC-MS/MS).

    Measured: 0, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days

Secondary outcomes (6)

  1. Total testosterone concentration

    Multiple blood will be collected before pellet implantation and 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days and total testosterone concentrations will be determined by Liquid chromatography - mass spectrometry

    Measured: Pre-insertion of the estradiol pellet; 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days,140 days and 168 days

  2. Estrone concentration

    Multiple blood will be collected before pellet implantation and 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours , 24 hours; 7 days, 14 days , 21 days , 28days , 56 days, 84 days, 112 days , 140 days and 168 days and estrone concentrations will be determined by LC-MS/MS.

    Measured: Pre-insertion of the estradiol pellet; 2h, 4h, 6h, 8h, 10h, 12, 24h; 7, 14, 21, 28, 56, 84, 112, 140 and 168 days

  3. Follicle - stimulating hormone FSH concentration

    Multiple blood will be collected before pellet implantation and 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days and Follicle-stimulating hormone concentrations will be determined by electrochemiluminescence

    Measured: Pre-insertion of the estradiol pellet; 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days

  4. Luteinizing hormone - hormone LH concentration

    Multiple blood will be collected before pellet implantation and 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days and Follicle-stimulating hormone concentrations will be determined by electrochemiluminescence

    Measured: Pre-insertion of the estradiol pellet; 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days

  5. Sex hormone binding globulin SHBG concentration

    Multiple blood will be collected before pellet implantation and 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days,28 dyas, 56 days, 84 days, 112 days, 140 days and 168 days and Follicle-stimulating hormone concentrations will be determined by electrochemiluminescence

    Measured: Pre-insertion of the estradiol pellet; 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days

  6. Prolactin concentration

    Multiple blood will be collected before pellet implantation and 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days and Follicle-stimulating hormone concentrations will be determined by electrochemiluminescence

    Measured: Pre-insertion of the estradiol pellet; 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days, 21 days, 28 days, 56 days, 84 days, 112 days, 140 days and 168 days

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted18 Nov 2023
  2. Study start13 Dec 2023
  3. Primary completion9 Oct 2024
  4. Study completion30 Jul 2025

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrolment
20 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT06136208
Sponsor's protocol ID
CLARA Study
Acronym
CLARA
Status last verified
Sep 2025
First submitted
31 Oct 2023
Last updated
8 Sep 2025
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No

Publications

  • Casals G, Costa RF, Rull EU, Escobar-Morreale HF, Argente J, Sesmilo G, Biagetti B. Recommendations for the measurement of sexual steroids in clinical practice. A position statement of SEQCML/SEEN/SEEP. Adv Lab Med. 2023 Mar 9;4(1):52-69. doi: 10.1515/almed-2023-0020. eCollection 2023 Apr.

    PubMed 37359897

  • del Carmen Cravioto M, Larrea F, Delgado NE, Escobar AR, Diaz-Sanchez V, Dominguez J, de Leon RP. Pharmacokinetics and pharmacodynamics of 25-mg estradiol implants in postmenopausal Mexican women. Menopause. 2001 Sep-Oct;8(5):353-60. doi: 10.1097/00042192-200109000-00010.

    PubMed 11528362

  • Hamoda H, Panay N, Pedder H, Arya R, Savvas M. The British Menopause Society & Women's Health Concern 2020 recommendations on hormone replacement therapy in menopausal women. Post Reprod Health. 2020 Dec;26(4):181-209. doi: 10.1177/2053369120957514. Epub 2020 Oct 12. No abstract available.

    PubMed 33045914

  • Kuhl H. Pharmacology of estrogens and progestogens: influence of different routes of administration. Climacteric. 2005 Aug;8 Suppl 1:3-63. doi: 10.1080/13697130500148875.

    PubMed 16112947

  • Lobo RA, March CM, Goebelsmann U, Krauss RM, Mishell DR Jr. Subdermal estradiol pellets following hysterectomy and oophorectomy. Effect upon serum estrone, estradiol, luteinizing hormone, follicle-stimulating hormone, corticosteroid binding globulin-binding capacity, testosterone-estradiol binding globulin-binding capacity, lipids, and hot flushes. Am J Obstet Gynecol. 1980 Nov 15;138(6):714-9.

    PubMed 6776814

  • Lobo RA. Hormone-replacement therapy: current thinking. Nat Rev Endocrinol. 2017 Apr;13(4):220-231. doi: 10.1038/nrendo.2016.164. Epub 2016 Oct 7.

    PubMed 27716751

  • Manson JE, Bassuk SS, Kaunitz AM, Pinkerton JV. The Women's Health Initiative trials of menopausal hormone therapy: lessons learned. Menopause. 2020 Aug;27(8):918-928. doi: 10.1097/GME.0000000000001553.

    PubMed 32345788

  • Notelovitz M, Johnston M, Smith S, Kitchens C. Metabolic and hormonal effects of 25-mg and 50-mg 17 beta-estradiol implants in surgically menopausal women. Obstet Gynecol. 1987 Nov;70(5):749-54.

    PubMed 3658285

  • Owen EJ, Siddle NC, McGarrigle HT, Pugh MA. 25 mg oestradiol implants--the dosage of first choice for subcutaneous oestrogen replacement therapy? Br J Obstet Gynaecol. 1992 Aug;99(8):671-5. doi: 10.1111/j.1471-0528.1992.tb13853.x.

    PubMed 1327094

  • Stanczyk FZ, Shoupe D, Nunez V, Macias-Gonzales P, Vijod MA, Lobo RA. A randomized comparison of nonoral estradiol delivery in postmenopausal women. Am J Obstet Gynecol. 1988 Dec;159(6):1540-6. doi: 10.1016/0002-9378(88)90591-1.

    PubMed 3144919

  • Stuenkel CA, Davis SR, Gompel A, Lumsden MA, Murad MH, Pinkerton JV, Santen RJ. Treatment of Symptoms of the Menopause: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2015 Nov;100(11):3975-4011. doi: 10.1210/jc.2015-2236. Epub 2015 Oct 7.

    PubMed 26444994

  • Suhonen SP, Allonen HO, Lahteenmaki P. Sustained-release subdermal estradiol implants: a new alternative in estrogen replacement therapy. Am J Obstet Gynecol. 1993 Nov;169(5):1248-54. doi: 10.1016/0002-9378(93)90291-p.

    PubMed 8238193

  • Thom MH, Collins WP, Studd JW. Hormonal profiles in postmenopausal women after therapy with subcutaneous implants. Br J Obstet Gynaecol. 1981 Apr;88(4):426-33. doi: 10.1111/j.1471-0528.1981.tb01008.x.

    PubMed 6784745

Questions about this trial

What is this clinical trial studying?

A study testing s.c 25 mg estradiol pellet in people with Climacteric Syndrome and Menopause, run by Science Valley Research Institute at 1 site in Brazil.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 9 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 8 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Brazil. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Serum total estradiol concentration (time frame: 0, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours; 7 days, 14 days , 21 days , 28 days , 56 days, 84 days, 112 days, 140 days and 168 days). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT06136208, which also lists 13 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Sep 2025.

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