Functional Hypothalamic AmenorrheaPhase 2KYRIADNCT07235917
A Study to Investigate Mibavademab in Adult Women With Functional Hypothalamic Amenorrhea
A Phase 2 study testing Mibavademab in people with Functional Hypothalamic Amenorrhea and FHA, run by Regeneron Pharmaceuticals at 11 sites in United States.
Trial summary
This study is researching an experimental drug called mibavademab (also called "study drug"). The study is focused on participants with a condition called Functional Hypothalamic Amenorrhea (FHA). Read more about this study
- Who is it for?
- Ages 18 to 40 years, women only
- Conditions the study is for
- Functional Hypothalamic Amenorrhea, FHA
- What is being tested?
- Mibavademab
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 34 participants
- Where
- 11 sitesUnited States
- Study dates
- 11 Mar 2026to 17 May 2028
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
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 18 to 40 years
- Women only
- No healthy volunteers
- Adult
Who may be able to join
- Diagnosis of FHA after exclusion of anatomic or organic causes of amenorrhea
- Has had no menstrual bleeding episode within 3 months prior to day 1, as described in the protocol
- Has a Body Mass Index (BMI) ≥18.5 and <25 kg/m^2 at screening, or BMI ≥25 to <30 kg/m^2 at screening AND percentage of body fat <23% from rigorous exercise as determined by the investigator through Standard of Care (SoC) methods (eg, skinfold thickness, DXA, bioimpedance) within 6 months of screening
Who cannot join
- Has presence of primary amenorrhea (failure to reach menarche, first menstrual cycle)
- Has blood estradiol ≥50 pg/mL or blood progesterone ≥1 ng/mL at screening, as described in the protocol
- Has uterine (eg, absence of uterus, prior endometrial ablation, endometriosis, outflow tract disorders) or ovarian conditions (eg, absence of an ovary, presence of large polycystic ovaries i.e. greater than 10 cc) that impact assessment of menses or of the HPO axis
- Has conditions other than FHA that may cause amenorrhea or menstrual cycle disturbances (eg, polycystic ovarian syndrome, hyperprolactinemia, primary ovarian insufficiency, untreated primary hypothyroidism, primary hyperthyroidism), as described in the protocol
- Polycystic ovarian morphology with an ovarian volume >10 cc on TransVaginal UltraSound (TVUS) [or TransAbdominal Pelvic Ultrasound (TAPU) if applicable] at baseline
- Presence of follicle ≥17 mm, evidence of ruptured follicle, and/or evidence of corpus luteum on TVUS (or TAPU if applicable) at baseline
- NOTE: Other protocol-defined Inclusion/Exclusion criteria apply
Trial locations and contacts
11 sites in 1 country. Contact the study team or a site near you to ask about taking part.
11 sites in 1 country
United States11 sites, 10 recruiting
- Recruiting
University of Virginia School of Medicine
Charlottesville, Virginia, 22908
- Recruiting
OBGYN Associates of Erie
Erie, Pennsylvania, 16507
- Recruiting
Penn State Health Milton South Hershey Medical Center
Hershey, Pennsylvania, 17033
- Withdrawn
Zillan Clinical Research
Houston, Texas, 77082
- Recruiting
Mayo Clinic Florida
Jacksonville, Florida, 32224
- Recruiting
Yale University School of Medicine
New Haven, Connecticut, 06510
- Recruiting
Tidewater Clinical Research - Tidewater Physicians for Women
Norfolk, Virginia, 23502
- Recruiting
University of Pittsburgh
Philadelphia, Pennsylvania, 15217
- Recruiting
Arensia Exploratory Medicine Clinic
Phoenix, Arizona, 85015
- Recruiting
Oregon Health and Science University (OHSU)
Portland, Oregon, 97239
- Recruiting
Focus Clinical Research
West Hills, California, 91307
About this study
Official title: A Phase 2, Double-Blind, Placebo-Controlled Study to Investigate the Safety and Efficacy of Mibavademab in Adult Women With Functional Hypothalamic Amenorrhea
This study is researching an experimental drug called mibavademab (also called "study drug"). The study is focused on participants with a condition called Functional Hypothalamic Amenorrhea (FHA). FHA is a condition where a woman stops menstruating because the brain is not sending the correct hormonal signals to the ovaries, which then are not able to cycle and ovulate properly.
The aim of the study is to see how well the study drug helps the body make the hormones necessary for ovulation and reproduction, and to assess its safety.
Read more
The study is looking at several other research questions, including:
- Whether the drug helps bone health
- What side effects may happen from taking the study drug
- How much study drug is in the blood at different times
- Whether the body makes antibodies against the study drug (which could make the study drug less effective or could lead to side effects)
- Conditions
- Functional Hypothalamic Amenorrhea, FHA
- Being tested
- Mibavademab, Placebo
- Keywords
- Secondary amenorrhea, Hypothalamic Pituitary Ovarian axis, HPO, Group I ovulation disorder, Hypogonadotropic hypogonadal anovulation, Gonadotropin Releasing Hormone Deficiency, GnRH Suppression, Amenorrhea, Female Infertility, Hypoestrogenism, Estrogen Deficiency, Menstrual Dysfunction, Menstrual Cycle Disturbance
- Medical subject headings
- Amenorrhea, Infertility, Female
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
MibavademabDrug
Also called REGN4461
Administered per the protocol
PlaceboOther
Administered per the protocol
| Study group | Role | What they receive |
|---|---|---|
| Mibavademab | Experimental | Not described Receives: Drug: Mibavademab |
| Placebo | Placebo comparator | Not described Receives: Other: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change from the highest serum estradiol observed during a 28-day period
Measured: Baseline to month 6
Secondary outcomes (20)
Change from the mean serum estradiol observed during a 28-day period
Measured: Baseline to month 6
Occurrence of menses followed by mid-cycle serum estradiol ≥200 pg/ml and mid-luteal serum progesterone ≥7.9 ng/ml
Measured: At month 6
Change in the highest serum estradiol
Measured: Baseline through 6 months
Occurrence of serum estradiol ≥200 pg/ml
Measured: Through 6 months
Number of ovulatory menstrual cycles
Measured: Through 6 months
Number of menses with mid-luteal serum progesterone ≥7.9 ng/ml and midluteal estradiol ≥100 pg/ml
Measured: Through 6 months
Number of menstrual cycles
Measured: Through 6 months
Percent change in Bone Mineral Density (BMD) at the lumbar spine, as measured by Dual X-ray Absorptiometry (DXA)
Measured: Baseline to 6 months
Absolute change in BMD at the lumbar spine, as measured by DXA
Measured: Baseline to 6 months
Percent change in Bone Mineral Content (BMC) at the lumbar spine, as measured by DXA
Measured: Baseline to 6 months
Absolute change in BMC at the lumbar spine, as measured by DXA
Measured: Baseline to 6 months
Percent change in BMD at the lumbar spine, as measured by DXA in participants with baseline lumbar spine BMD Z-score <-1
Measured: Baseline to 6 months
Absolute change in BMD at the lumbar spine, as measured by DXA, in participants with baseline lumbar spine BMD Z-score <-1
Measured: Baseline to 6 months
Percent change in BMC at the lumbar spine, as measured by DXA, in participants with baseline lumbar spine BMD Z-score <-1
Measured: Baseline to 6 months
Absolute change in BMC at the lumbar spine, as measured by DXA, in participants with baseline lumbar spine BMD Z-score <-1
Measured: Baseline to 6 months
Occurrence of Treatment Emergent of Adverse Events (TEAEs)
Measured: Up to day 280
Severity of TEAEs
Measured: Up to day 280
Concentrations of total mibavademab in serum
Measured: Up to day 280
Occurrence of Anti-Drug Antibodies (ADA) to mibavademab
Measured: Up to day 280
Magnitude of ADA to mibavademab
Measured: Up to day 280
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 Nov 2025
- Study start11 Mar 2026
- Primary completion28 Jan 2028 (estimated)
- Study completion17 May 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Functional Hypothalamic AmenorrheaStudies of the same condition, open and under way.
- More trials run by Regeneron PharmaceuticalsThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
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 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 34 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Regeneron Pharmaceuticals
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Clinical Trial Management, Study director, Regeneron Pharmaceuticals
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07235917
- Sponsor's protocol ID
- R4461-FHA-2485
- Acronym
- KYRIAD
- Status last verified
- Nov 2026
- First submitted
- 14 Nov 2025
- Last updated
- 4 Nov 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: All Individual Patient Data (IPD) that underlie publicly available results will be considered for sharing.
Study at a glance
From the registry record, last updated by the sponsor on 4 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 2, Double-Blind, Placebo-Controlled Study to Investigate the Safety and Efficacy of Mibavademab in Adult Women With Functional Hypothalamic Amenorrhea
- ClinicalTrials.gov ID
- NCT07235917
- Acronym / sponsor ID
- KYRIAD / R4461-FHA-2485
- Conditions
- Functional Hypothalamic Amenorrhea, FHA
- Keywords
- Secondary amenorrhea, Hypothalamic Pituitary Ovarian axis, HPO, Group I ovulation disorder, Hypogonadotropic hypogonadal anovulation, Gonadotropin Releasing Hormone Deficiency, GnRH Suppression, Amenorrhea
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 34 participants (estimated)
- Lead sponsor
- Regeneron PharmaceuticalsIndustry (pharma, biotech, devices)
- Study start
- 11 Mar 2026 (actual)
- Primary completion
- 28 Jan 2028 (estimated)
- Study completion
- 17 May 2028 (estimated)
- First posted
- 19 Nov 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study is researching an experimental drug called mibavademab (also called "study drug"). The study is focused on participants with a condition called Functional Hypothalamic Amenorrhea (FHA). FHA is a condition where a woman stops menstruating because the brain is not sending the correct hormonal signals to the ovaries, which then are not able to cycle and ovulate properly.
The aim of the study is to see how well the study drug helps the body make the hormones necessary for ovulation and reproduction, and to assess its safety.
The study is looking at several other research questions, including:
- Whether the drug helps bone health
- What side effects may happen from taking the study drug
- How much study drug is in the blood at different times
- Whether the body makes antibodies against the study drug (which could make the study drug less effective or could lead to side effects)
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Mibavademab | Experimental | Drug: Mibavademab |
| Placebo | Placebo comparator | Other: Placebo |
Who may qualify
- Ages
- 18 to 40 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- Diagnosis of FHA after exclusion of anatomic or organic causes of amenorrhea
- Has had no menstrual bleeding episode within 3 months prior to day 1, as described in the protocol
- Has a Body Mass Index (BMI) ≥18.5 and <25 kg/m^2 at screening, or BMI ≥25 to <30 kg/m^2 at screening AND percentage of body fat <23% from rigorous exercise as determined by the investigator through Standard of Care (SoC) methods (eg, skinfold thickness, DXA, bioimpedance) within 6 months of screening
Key exclusion criteria (7 listed)
- Has presence of primary amenorrhea (failure to reach menarche, first menstrual cycle)
- Has blood estradiol ≥50 pg/mL or blood progesterone ≥1 ng/mL at screening, as described in the protocol
- Has uterine (eg, absence of uterus, prior endometrial ablation, endometriosis, outflow tract disorders) or ovarian conditions (eg, absence of an ovary, presence of large polycystic ovaries i.e. greater than 10 cc) that impact assessment of menses or of the HPO axis
- Has conditions other than FHA that may cause amenorrhea or menstrual cycle disturbances (eg, polycystic ovarian syndrome, hyperprolactinemia, primary ovarian insufficiency, untreated primary hypothyroidism, primary hyperthyroidism), as described in the protocol
- Polycystic ovarian morphology with an ovarian volume >10 cc on TransVaginal UltraSound (TVUS) [or TransAbdominal Pelvic Ultrasound (TAPU) if applicable] at baseline
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| MibavademabAlso: REGN4461Administered per the protocol | Drug | Mibavademab |
| PlaceboAdministered per the protocol | Other | Placebo |
Primary outcome
Change from the highest serum estradiol observed during a 28-day period
Time frame: Baseline to month 6
20 secondary outcomes
Change from the mean serum estradiol observed during a 28-day period
Time frame: Baseline to month 6
Occurrence of menses followed by mid-cycle serum estradiol ≥200 pg/ml and mid-luteal serum progesterone ≥7.9 ng/ml
Time frame: At month 6
Change in the highest serum estradiol
Time frame: Baseline through 6 months
Occurrence of serum estradiol ≥200 pg/ml
Time frame: Through 6 months
Number of ovulatory menstrual cycles
Time frame: Through 6 months
Number of menses with mid-luteal serum progesterone ≥7.9 ng/ml and midluteal estradiol ≥100 pg/ml
Time frame: Through 6 months
Number of menstrual cycles
Time frame: Through 6 months
Percent change in Bone Mineral Density (BMD) at the lumbar spine, as measured by Dual X-ray Absorptiometry (DXA)
Time frame: Baseline to 6 months
Absolute change in BMD at the lumbar spine, as measured by DXA
Time frame: Baseline to 6 months
Percent change in Bone Mineral Content (BMC) at the lumbar spine, as measured by DXA
Time frame: Baseline to 6 months
Absolute change in BMC at the lumbar spine, as measured by DXA
Time frame: Baseline to 6 months
Percent change in BMD at the lumbar spine, as measured by DXA in participants with baseline lumbar spine BMD Z-score <-1
Time frame: Baseline to 6 months
Absolute change in BMD at the lumbar spine, as measured by DXA, in participants with baseline lumbar spine BMD Z-score <-1
Time frame: Baseline to 6 months
Percent change in BMC at the lumbar spine, as measured by DXA, in participants with baseline lumbar spine BMD Z-score <-1
Time frame: Baseline to 6 months
Absolute change in BMC at the lumbar spine, as measured by DXA, in participants with baseline lumbar spine BMD Z-score <-1
Time frame: Baseline to 6 months
Occurrence of Treatment Emergent of Adverse Events (TEAEs)
Time frame: Up to day 280
Severity of TEAEs
Time frame: Up to day 280
Concentrations of total mibavademab in serum
Time frame: Up to day 280
Occurrence of Anti-Drug Antibodies (ADA) to mibavademab
Time frame: Up to day 280
Magnitude of ADA to mibavademab
Time frame: Up to day 280
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Nov 2026.
- Related InfoLink provided by the sponsor.
- Individual participant dataSharing planned: Yes. All Individual Patient Data (IPD) that underlie publicly available results will be considered for sharing.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Clinical Trial Management study director
Regeneron Pharmaceuticals
11 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Mibavademab in people with Functional Hypothalamic Amenorrhea and FHA, run by Regeneron Pharmaceuticals at 11 sites in United States.
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 3 inclusion and 7 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: looking for participants now, as of the sponsor's last update on 4 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 11 sites in United States. 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. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Clinical Trials Administrator (844-734-6643, clinicaltrials@regeneron.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change from the highest serum estradiol observed during a 28-day period (time frame: Baseline to month 6). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 4 Nov 2026; AzTrials last refreshed its copy on 8 Nov 2026.