Central Precocious PubertyPhase 3NCT06129539
A Study to Assess the Efficacy, Safety, and Pharmacokinetics of Debio 4326 in Pediatric Participants With Central Precocious Puberty (LIBELULA™ Clinical Trial)
A Phase 3 study testing Debio 4326 in people with Central Precocious Puberty, run by Debiopharm International SA at 17 sites in 5 countries.
Trial summary
The primary objective of this study is to evaluate the efficacy of Debio 4326 in suppressing serum luteinizing hormone (LH) to prepubertal levels 52 weeks after the first Debio 4326 injection in pediatric participants with central precocious puberty (CPP). Read more about this study
- Who is it for?
- Ages 5 to 8 years
- Conditions the study is for
- Central Precocious Puberty
- What is being tested?
- Debio 4326
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 56 participants
- Where
- 17 sitesin 5 countries
- Study dates
- 31 Jul 2024to Feb 2028
- Phase
- Phase 3
- 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 5 to 8 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Diagnosis of central precocious puberty.
- Onset of development of sex characteristics (i.e., breast development in girls or testicular enlargement in boys according to the Tanner method) before the age of 8 years in girls and 9 years in boys.
- Initially, only participants aged (a) 5 to 8 years inclusive (i.e., <9 years) are eligible. The Sponsor will determine based on the recommendation of the DMC following the interim analysis whether participants aged (b) 2 to 4 years inclusive (i.e., <5 years) and/or (c) 9 to 10 years inclusive (i.e., <11 years) may be recruited.
- Participant to receive at least 1 year of gonadotropin-releasing hormone agonist (GnRHa) therapy from study treatment start.
- (a) Pre-treated participants: Start of initial GnRHa therapy no later than 18 months after onset of the first signs of CPP.
- Treatment-naive participants: Start of Debio 4326 treatment no later than 18 months after onset of the first signs of CPP.
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- (a) Pre-treated participants: Difference between bone age (Greulich and Pyle method) and chronological age of ≥1 year based on historical values at the initiation of the GnRHa therapy.
- Treatment-naive participants: Difference between bone age (Greulich and Pyle method) and chronological age of ≥1 year.
- (a) Pre-treated participants: Pubertal-type LH response (LH ≥6 IU/L) following a GnRH/GnRHa stimulation test, or random non-stimulated serum LH >0.5 IU/L (if considered local standard of care), based on historical values prior to the initiation of GnRHa therapy.
- Treatment-naive participants: Pubertal-type LH response (≥6 IU/L) 30 minutes following a GnRHa [leuprolide acetate 20 micrograms per kilogram (μg/kg) subcutaneous injection (SC)] stimulation test before treatment initiation.
- (a) Pre-treated participants: Clinical evidence of puberty, defined as Tanner Staging ≥2 for breast development for girls and testicular volume ≥4 milliliter (mL) (cubic centimeter [cc]) for boys, prior to the initiation of GnRHa therapy.
- Treatment-naive participants: Clinical evidence of puberty, defined as Tanner Staging ≥2 for breast development for girls and testicular volume ≥4 mL (cc) for boys.
Who cannot join
- Gonadotropin-independent (peripheral) precocious puberty: gonadotropin-independent gonadal or adrenal sex steroid secretion.
- (a) Pre-treated participants: Non-progressing, isolated premature thelarche prior to the initial GnRHa therapy.
- Treatment-naive participants: Non-progressing, isolated premature thelarche.
- Presence of an unstable intracranial tumor or an intracranial tumor potentially requiring neurosurgery or cerebral irradiation. Participants with hamartomas not requiring surgery are eligible.
- Any other condition or chronic illness possibly interfering with growth (e.g., renal failure, diabetes, moderate to severe scoliosis, previously treated intracranial tumor).
- Other than GnRHa therapy in pre-treated participants, any ongoing treatment with a potential effect on serum levels of gonadotropins or sex steroids, or possibly interfering with growth, opioids, central nervous system [CNS] stimulants).
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- Prior or current therapy with medroxyprogesterone acetate, growth hormone, or Insulin-like growth factor-1 (IGF-1).
- Diagnosis of short stature, i.e., more than 2.25 standard deviations (SD) below the mean height-for-age.
- Known history of seizures, epilepsy, and/or central nervous system disorders that may have been associated with seizures or convulsions.
- Prior (within 2 months of study treatment start) or current use of medications that have been associated with seizures or convulsions.
- Use of anticoagulants (heparin or coumarin derivatives).
- Note: Other inclusion/exclusion criteria mentioned in the protocol may apply.
Trial locations and contacts
17 sites in 5 countries.
17 sites in 5 countries
Brazil7 sites
Hospital Da Criança de Brasília Jose Alencar
Brasília, 70684-831
Hospital Universitario Walter Cantidio
Fortaleza, 60430-270
Clínica de Endocrinologia e Metabologia Ltda
Lago Sul, 71625175
Nucleo de Pesquisa Clínica do Rio Grande do Sul-NPCRS
Porto Alegre, 90430-001
CPQuali Pesquisa Clinica
São Paulo, 01228000
Irmandade Santa Casa de São Paulo
São Paulo, REG1 01222-020
Integral Pesquisa e Ensino
Votuporanga, 15501-405
Argentina4 sites
Instituto de Investigaciones Metabolicas (IDIM)
Buenos Aires, C1012AAR
Centro Medico Dra Laura Maffei Investigacion Clinica Aplicada
Buenos Aires, C1425AGC
Centro de Investigaciones Medicas Mar del Plata
Mar del Plata, B7600FYK
Clinica Mayo de Urgencias Medicas Cruz Blanca S.R.L
San Miguel de Tucumán, T4000
United States3 sites
Prisma Health Pediatric Endocrinology
Columbia, South Carolina, 29203
Rady Children's Hospital - San Diego
San Diego, California, 92123
University of California San Francisco-Benioff Children's Hospital
San Francisco, California, 94143
Chile2 sites
ENDOMET
Antofagasta, 1271987
Hospital Clinico San Borja Arriaran (HCSBA)
Santiago, 8360160
Mexico1 site
Christus Latam Hub Center of Excellence and Innovation S C
Monterrey, 64060
About this study
Official title: LIBELULA™: An Open-label, Single-arm, Multi-center, Phase 3 Study on the Efficacy, Safety, and Pharmacokinetics of Debio 4326, a Triptorelin 12-month Formulation, in Pediatric Participants With Central Precocious Puberty
The primary objective of this study is to evaluate the efficacy of Debio 4326 in suppressing serum luteinizing hormone (LH) to prepubertal levels 52 weeks after the first Debio 4326 injection in pediatric participants with central precocious puberty (CPP).
- Conditions
- Central Precocious Puberty
- Being tested
- Debio 4326
- Medical subject headings
- Puberty, Precocious
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Debio 4326Drug
Administered as an intramuscular (IM) injection
| Study group | Role | What they receive |
|---|---|---|
| Debio 4326 | Experimental | Participants will receive the first injection of Debio 4326, on Day 1 in Part A followed by a second injection 52 weeks later in Part B of the study. Receives: Drug: Debio 4326 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Part A: Percentage of Participants With Suppression of Gonadotropin-Releasing Hormone Agonist Stimulated Serum Luteinizing Hormone (LH) to Less Than or Equal to (≤)5 International Units per Liter (IU/L)
Measured: Week 52 in Part A
Secondary outcomes (22)
Parts A and B: Number of Participants With Treatment-Emergent Adverse Events (TEAEs), Adverse Events of Special Interest (AESIs) and Serious TEAEs
Measured: Up to 104 weeks
Parts A and B: Number of Participants with Clinically Significant Abnormalities in Vital Signs
Measured: Up to 104 weeks
Parts A and B: Change From Baseline in Body Weight
Measured: Up to 104 weeks
Parts A and B: Change From Baseline in Body Mass Index
Measured: Up to 104 weeks
Parts A and B: Number of Participants With Erythema, Swelling, and Induration at the Injection Site Immediately and 2 Hours After Each Debio 4326 Injection as per Investigator's Assessment
Measured: Up to 2 hours post-dose on Day 1 in both Parts A and B
Parts A and B: Number of Participants With Pain at the Injection Site Immediately and 2 Hours After Each Debio 4326 Injection as per Participant's Assessment Using the Wong-Baker FACES® Pain Rating Scale
Measured: Up to 2 hours post-dose on Day 1 in both Parts A and B
Parts A and B: Percentage of Participants Who do not Exhibit the Acute-on-Chronic (AOC) Phenomenon
Measured: Up to 48 hours post-dose on Day 3 in both Parts A and B
Parts A and B: Percentage of Participants With Stimulated Serum LH ≤5 IU/L
Measured: Up to Week 52 in both Parts A and B
Parts A and B: Percentage of Participants With Stimulated Serum LH ≤4 IU/L
Measured: Up to Week 52 in both Parts A and B
Parts A and B: Number of Participants With Change in Hormone Levels
The following hormones will be assessed: basal LH, follicle-stimulating hormone (FSH), estradiol, testosterone, GnRHa-stimulated LH, and GnRHa-stimulated FSH.
Measured: Up to Week 52 in both Parts A and B
Parts A and B: Percentage of Girls With Prepubertal Serum Estradiol <20 pg/mL (<73 pmol/L)
Measured: Up to Week 52 in both Parts A and B
Parts A and B: Percentage of Boys With Testosterone <30 ng/dL (<1.0 nmol/L)
Measured: Up to Week 52 in both Parts A and B
Parts A and B: Change From Baseline in Height-for-Age Z Score
Measured: Baseline, up to Week 52 in both Parts A and B
Parts A and B: Number of Participants With Change From Baseline in Growth Velocity
Measured: Up to Week 52 in both Parts A and B
Percentage of Participants in Whom the Bone Age/Chronological Age Did Not Rise Relative to Baseline
Measured: Part A: Baseline, up to Week 52 in both Parts A and B
Parts A and B: Percentage of Participants Who Achieve Stabilization of Sexual Maturation (Regression or Stabilization Compared to Baseline by Tanner Staging)
Measured: Baseline, Weeks 26 and 52 in both Parts A and B
Parts A and B: Percentage of Girls With Regression of Uterine Length (Using Transabdominal Ultrasound)
Measured: Weeks 26 and 52 in both Parts A and B
Parts A and B: Percentage of Boys With Absence of Progression of Testis Volumes (Clinical Assessment With Orchidometer)
Measured: Weeks 26 and 52 in both Parts A and B
Parts A and B: Plasma Concentration of Triptorelin
The pharmacokinetics (PK) of triptorelin will be evaluated in plasma.
Measured: Pre-dose and at multiple timepoints post-dose up to 52 weeks in Part A and 64 weeks in Part B
Percentage of Participants With Stimulated Serum LH Levels Greater Than (>)5 IU/L at Post Treatment Visit (PTV)
This outcome measure will be analyzed only in participants who stop all hormonal treatment with any GnRHa at end of treatment (EOT).
Measured: 64 weeks after the last Debio 4326 injection in Part A or B
Part B: Accumulation Ratio on Maximum Serum Concentration (RacCmax)
Measured: At multiple timepoints post-dose up to 48 hours (Day 2) in Part B
Part B: Accumulation Ratio on Serum Concentration at the End of the Dosing Interval (RacCtrough)
Measured: At multiple timepoints post-dose up to 52 weeks in Part B
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Nov 2023
- Study start31 Jul 2024
- Primary completionOct 2026 (estimated)
- Study completionFeb 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Central Precocious PubertyStudies of the same condition, open and under way.
- 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 3
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 56 participants (actual)
Sponsor and investigators
- Lead sponsor
- Debiopharm International SA
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Study Director, Study director, Debiopharm International SA
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06129539
- Sponsor's protocol ID
- Debio 4326-301
- Status last verified
- Oct 2026
- First submitted
- 8 Nov 2023
- Last updated
- 23 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 23 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- LIBELULA™: An Open-label, Single-arm, Multi-center, Phase 3 Study on the Efficacy, Safety, and Pharmacokinetics of Debio 4326, a Triptorelin 12-month Formulation, in Pediatric Participants With Central Precocious Puberty
- ClinicalTrials.gov ID
- NCT06129539
- Acronym / sponsor ID
- Debio 4326-301
- Conditions
- Central Precocious Puberty
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 56 participants (actual)
- Lead sponsor
- Debiopharm International SAIndustry (pharma, biotech, devices)
- Study start
- 31 Jul 2024 (actual)
- Primary completion
- Oct 2026 (estimated)
- Study completion
- Feb 2028 (estimated)
- First posted
- 13 Nov 2023 (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.
The primary objective of this study is to evaluate the efficacy of Debio 4326 in suppressing serum luteinizing hormone (LH) to prepubertal levels 52 weeks after the first Debio 4326 injection in pediatric participants with central precocious puberty (CPP).
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Debio 4326 | Experimental | Drug: Debio 4326Participants will receive the first injection of Debio 4326, on Day 1 in Part A followed by a second injection 52 weeks later in Part B of the study. |
Who may qualify
- Ages
- 5 to 8 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (12 listed)
- Diagnosis of central precocious puberty.
- Onset of development of sex characteristics (i.e., breast development in girls or testicular enlargement in boys according to the Tanner method) before the age of 8 years in girls and 9 years in boys.
- Initially, only participants aged (a) 5 to 8 years inclusive (i.e., <9 years) are eligible. The Sponsor will determine based on the recommendation of the DMC following the interim analysis whether participants aged (b) 2 to 4 years inclusive (i.e., <5 years) and/or (c) 9 to 10 years inclusive (i.e., <11 years) may be recruited.
- Participant to receive at least 1 year of gonadotropin-releasing hormone agonist (GnRHa) therapy from study treatment start.
- (a) Pre-treated participants: Start of initial GnRHa therapy no later than 18 months after onset of the first signs of CPP.
Key exclusion criteria (12 listed)
- Gonadotropin-independent (peripheral) precocious puberty: gonadotropin-independent gonadal or adrenal sex steroid secretion.
- (a) Pre-treated participants: Non-progressing, isolated premature thelarche prior to the initial GnRHa therapy.
- Presence of an unstable intracranial tumor or an intracranial tumor potentially requiring neurosurgery or cerebral irradiation. Participants with hamartomas not requiring surgery are eligible.
- Any other condition or chronic illness possibly interfering with growth (e.g., renal failure, diabetes, moderate to severe scoliosis, previously treated intracranial tumor).
- Other than GnRHa therapy in pre-treated participants, any ongoing treatment with a potential effect on serum levels of gonadotropins or sex steroids, or possibly interfering with growth, opioids, central nervous system [CNS] stimulants).
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 |
|---|---|---|
| Debio 4326Administered as an intramuscular (IM) injection | Drug | Debio 4326 |
Primary outcome
Part A: Percentage of Participants With Suppression of Gonadotropin-Releasing Hormone Agonist Stimulated Serum Luteinizing Hormone (LH) to Less Than or Equal to (≤)5 International Units per Liter (IU/L)
Time frame: Week 52 in Part A
22 secondary outcomes
Parts A and B: Number of Participants With Treatment-Emergent Adverse Events (TEAEs), Adverse Events of Special Interest (AESIs) and Serious TEAEs
Time frame: Up to 104 weeks
Parts A and B: Number of Participants with Clinically Significant Abnormalities in Vital Signs
Time frame: Up to 104 weeks
Parts A and B: Change From Baseline in Body Weight
Time frame: Up to 104 weeks
Parts A and B: Change From Baseline in Body Mass Index
Time frame: Up to 104 weeks
Parts A and B: Number of Participants With Erythema, Swelling, and Induration at the Injection Site Immediately and 2 Hours After Each Debio 4326 Injection as per Investigator's Assessment
Time frame: Up to 2 hours post-dose on Day 1 in both Parts A and B
Parts A and B: Number of Participants With Pain at the Injection Site Immediately and 2 Hours After Each Debio 4326 Injection as per Participant's Assessment Using the Wong-Baker FACES® Pain Rating Scale
Time frame: Up to 2 hours post-dose on Day 1 in both Parts A and B
Parts A and B: Percentage of Participants Who do not Exhibit the Acute-on-Chronic (AOC) Phenomenon
Time frame: Up to 48 hours post-dose on Day 3 in both Parts A and B
Parts A and B: Percentage of Participants With Stimulated Serum LH ≤5 IU/L
Time frame: Up to Week 52 in both Parts A and B
Parts A and B: Percentage of Participants With Stimulated Serum LH ≤4 IU/L
Time frame: Up to Week 52 in both Parts A and B
Parts A and B: Number of Participants With Change in Hormone Levels
Time frame: Up to Week 52 in both Parts A and B
Parts A and B: Percentage of Girls With Prepubertal Serum Estradiol <20 pg/mL (<73 pmol/L)
Time frame: Up to Week 52 in both Parts A and B
Parts A and B: Percentage of Boys With Testosterone <30 ng/dL (<1.0 nmol/L)
Time frame: Up to Week 52 in both Parts A and B
Parts A and B: Change From Baseline in Height-for-Age Z Score
Time frame: Baseline, up to Week 52 in both Parts A and B
Parts A and B: Number of Participants With Change From Baseline in Growth Velocity
Time frame: Up to Week 52 in both Parts A and B
Percentage of Participants in Whom the Bone Age/Chronological Age Did Not Rise Relative to Baseline
Time frame: Part A: Baseline, up to Week 52 in both Parts A and B
Parts A and B: Percentage of Participants Who Achieve Stabilization of Sexual Maturation (Regression or Stabilization Compared to Baseline by Tanner Staging)
Time frame: Baseline, Weeks 26 and 52 in both Parts A and B
Parts A and B: Percentage of Girls With Regression of Uterine Length (Using Transabdominal Ultrasound)
Time frame: Weeks 26 and 52 in both Parts A and B
Parts A and B: Percentage of Boys With Absence of Progression of Testis Volumes (Clinical Assessment With Orchidometer)
Time frame: Weeks 26 and 52 in both Parts A and B
Parts A and B: Plasma Concentration of Triptorelin
Time frame: Pre-dose and at multiple timepoints post-dose up to 52 weeks in Part A and 64 weeks in Part B
Percentage of Participants With Stimulated Serum LH Levels Greater Than (>)5 IU/L at Post Treatment Visit (PTV)
Time frame: 64 weeks after the last Debio 4326 injection in Part A or B
Part B: Accumulation Ratio on Maximum Serum Concentration (RacCmax)
Time frame: At multiple timepoints post-dose up to 48 hours (Day 2) in Part B
Part B: Accumulation Ratio on Serum Concentration at the End of the Dosing Interval (RacCtrough)
Time frame: At multiple timepoints post-dose up to 52 weeks in Part B
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 23 Oct 2026.
- Individual participant dataSharing planned: No
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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. This study is not recruiting at the moment.
Study Director study director
Debiopharm International SA
17 sites in 5 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Debio 4326 in people with Central Precocious Puberty, run by Debiopharm International SA at 17 sites in 5 countries.
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 12 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: under way, not looking for participants, as of the sponsor's last update on 23 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 17 sites in Brazil, Argentina, United States, Chile, Mexico. 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.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
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?
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?
Part A: Percentage of Participants With Suppression of Gonadotropin-Releasing Hormone Agonist Stimulated Serum Luteinizing Hormone (LH) to Less Than or Equal to (≤)5 International Units per Liter (IU/L) (time frame: Week 52 in Part A). 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 23 Oct 2026.