A Phase 3 interventional study of TransCon hGH in Growth Hormone Deficiency, Pediatric, Endocrine System Diseases and Hormone Deficiency, sponsored by Ascendis Pharma A/S. Completed at 42 sites in 11 countries. Open to participants aged 1 Year to 18 Years. Per ClinicalTrials.gov, last updated 2026-07-07.
Sponsored by Ascendis Pharma A/S · Phase 3, Interventional, and Treatment
A multicenter, phase 3, long-term extension trial of TransCon hGH administered once-weekly in children with growth hormone deficiency (GHD) who previously participated in a phase 3 TransCon hGH trial. Approximately 300 children (males and females) with GHD will be included. All study participants will receive TransCon hGH. This is a global trial that will be conducted in, but not limited to, the United States, Poland, Bulgaria, Ukraine, Armenia, Russia and Australia.
252 studies on the registry are indexed under Dwarfism, Pituitary; 30 are open to participants now.
This study's enrollment of 298 is above the median of 60 across 169 interventional studies indexed under Dwarfism, Pituitary.
Browse Dwarfism, Pituitary studies →Ascendis Pharma A/S is the lead sponsor of 17 studies on the registry; 7 are open to participants now.
Counted across the registry records on this site, refreshed daily.
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.
Exclusion Criteria:
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.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Once weekly subcutaneous injection of TransCon hGH
Drug: TransCon hGH
Once weekly subcutaneous injection of TransCon hGH
Number of Subjects With Treatment-Emergent Adverse Events [Long-Term Safety and Tolerability]
Long-term safety and tolerability of weekly lonapegsomatropin (TransCon hGH) treatment
Time frame: Up to Week 208
Annualized Height Velocity by Visit
Annualized height velocity (AHV) by visit with long-term dosing of weekly lonapegsomatropin treatment
Time frame: Up to Week 208
IGF-1 SDS by Visit
Insulin-like Growth Factor-1 (IGF-1) standard deviation score (SDS) by visit with long-term dosing of weekly lonapegsomatropin treatment at Week 13, Week 52, Week 104, Week 156, and Week 208. IGF-1 SDS is the number of standard deviations above or below the mean IGF-1 level for a child of the same age and sex. The target range for IGF-1 SDS was 0 to +2. An IGF-1 SDS of 0 represents the population mean. If the IGF-1 SDS is \< 0, then the negative score indicates an IGF-1 below the mean IGF-1 for a child of the same age and sex. If the IGF-1 SDS is \> 0, then the positive score indicates an IGF-1 above the mean IGF-1 for a child of the same age and sex. A positive score of IGF-1 SDS indicates a better outcome.
Time frame: Up to Week 208
Height SDS - Change From Baseline
Change in Height Standard Deviation Score (SDS) from baseline with long-term dosing of weekly lonapegsomatropin treatment at Week 13, Week 52, Week 104, Week 156, and Week 208. Height SDS is the number of standard deviations above or below the mean height for age and sex. A Standard Deviation Score of 0 equals the population mean. If the Height SDS is \< 0, then the negative score indicates a height below the mean height for a child of the same age and sex. If the Height SDS is \> 0, then the positive score indicates a height above the mean height for a child of the same age and sex. A positive change from baseline in Height SDS indicates improved outcomes.
Time frame: Up to Week 208
Overall, 298 subjects entered the extension trial from the parent trials: 103 subjects from the CT-301 Lonapegsomatropin group, 55 subjects from the CT-301 Genotropin group, and 140 subjects from the CT-302 Lonapegsomatropin group.
| Milestone | Lonapegsomatropin |
|---|---|
| Started | 298 |
| Completed | 259 |
| Not completed | 39 |
| Withdrew: Physician decision | 1 |
| Withdrew: Withdrawal by subject | 16 |
| Withdrew: Other reasons | 10 |
| Withdrew: Lost to follow-up | 9 |
| Withdrew: Protocol violation | 3 |
Long-term safety and tolerability of weekly lonapegsomatropin (TransCon hGH) treatment
| Participants | Lonapegsomatropin |
|---|---|
| Number of Subjects With Treatment-Emergent Adverse Events [Long-Term Safety and Tolerability] | 226 |
Annualized height velocity (AHV) by visit with long-term dosing of weekly lonapegsomatropin treatment
| cm/year | Lonapegsomatropin |
|---|---|
| Week 13 | 8.904 ± 2.795 |
| Week 52 | 8.560 ± 1.801 |
| Week 104 | 7.854 ± 1.953 |
| Week 156 | 7.081 ± 1.838 |
| Week 208 | 6.462 ± 1.868 |
Insulin-like Growth Factor-1 (IGF-1) standard deviation score (SDS) by visit with long-term dosing of weekly lonapegsomatropin treatment at Week 13, Week 52, Week 104, Week 156, and Week 208. IGF-1 SDS is the number of standard deviations above or below the mean IGF-1 level for a child of the same age and sex. The target range for IGF-1 SDS was 0 to +2. An IGF-1 SDS of 0 represents the population mean. If the IGF-1 SDS is \< 0, then the negative score indicates an IGF-1 below the mean IGF-1 for a child of the same age and sex. If the IGF-1 SDS is \> 0, then the positive score indicates an IGF-1 above the mean IGF-1 for a child of the same age and sex. A positive score of IGF-1 SDS indicates a better outcome.
| Standard Deviation Score | Lonapegsomatropin |
|---|---|
| Week 13 | 1.210 ± 1.400 |
| Week 52 | 1.355 ± 1.231 |
| Week 104 | 1.613 ± 1.189 |
| Week 156 | 1.453 ± 1.125 |
| Week 208 | 1.597 ± 1.177 |
Change in Height Standard Deviation Score (SDS) from baseline with long-term dosing of weekly lonapegsomatropin treatment at Week 13, Week 52, Week 104, Week 156, and Week 208. Height SDS is the number of standard deviations above or below the mean height for age and sex. A Standard Deviation Score of 0 equals the population mean. If the Height SDS is \< 0, then the negative score indicates a height below the mean height for a child of the same age and sex. If the Height SDS is \> 0, then the positive score indicates a height above the mean height for a child of the same age and sex. A positive change from baseline in Height SDS indicates improved outcomes.
| Standard Deviation Score | Lonapegsomatropin |
|---|---|
| Week 13 | 0.141 ± 0.125 |
| Week 52 | 0.491 ± 0.307 |
| Week 104 | 0.841 ± 0.487 |
| Week 156 | 1.089 ± 0.534 |
| Week 208 | 1.242 ± 0.652 |
Collected over From Informed Consent Form signature up to 14 days after the final dose, up to 260 weeks.. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Lonapegsomatropin | 0/298 (0%) | 21/298 (7%) | 225/298 (75.5%) |
| Event | Lonapegsomatropin |
|---|---|
| COVID-19Infections and infestations | 3/298 |
| PneumoniaInfections and infestations | 2/298 |
| Femur fractureInjury, poisoning and procedural complications | 1/298 |
| Forearm fractureInjury, poisoning and procedural complications | 1/298 |
| Humerus fractureInjury, poisoning and procedural complications | 1/298 |
| Limb injuryInjury, poisoning and procedural complications | 1/298 |
| Lip injuryInjury, poisoning and procedural complications | 1/298 |
| Upper limb fractureInjury, poisoning and procedural complications | 1/298 |
| Diverticulitis Meckel'sCongenital, familial and genetic disorders | 1/298 |
| Brain stem infarctionNervous system disorders | 1/298 |
| Event | Lonapegsomatropin |
|---|---|
| Upper respiratory tract infectionInfections and infestations | 65/298 |
| COVID-19Infections and infestations | 40/298 |
| NasopharyngitisInfections and infestations | 40/298 |
| PyrexiaGeneral disorders | 37/298 |
| HeadacheNervous system disorders | 35/298 |
| InfluenzaInfections and infestations | 30/298 |
| CoughRespiratory, thoracic and mediastinal disorders | 28/298 |
| Pharyngitis streptococcalInfections and infestations | 27/298 |
| VomitingGastrointestinal disorders | 24/298 |
| Respiratory tract infection viralInfections and infestations | 22/298 |
| Age, Continuous(years) | Lonapegsomatropin |
|---|---|
| Mean | 10.27 ± 3.421 |
| Age, Customized(Participants) | Lonapegsomatropin |
|---|---|
| Infants and toddlers (28 days-23 months) | 1 |
| Children (2-11 years) | 196 |
| Adolescents (12-17 years) | 101 |
| Sex: Female, Male(Participants) | Lonapegsomatropin |
|---|---|
| Female | 63 |
| Male | 235 |
| Race/Ethnicity, Customized(Participants) | Lonapegsomatropin |
|---|---|
| Asian | 6 |
| Black or African American | 5 |
| Native Hawaiian or other Pacific Islander | 2 |
| White | 270 |
| Multiple | 3 |
| Other | 4 |
| Unknown | 8 |
| Race/Ethnicity, Customized(Participants) | Lonapegsomatropin |
|---|---|
| Hispanic or Latino | 15 |
| Not Hispanic or Latino | 272 |
| Not reported | 8 |
| Unknown | 3 |
| Region of Enrollment(Participants) | Lonapegsomatropin |
|---|---|
| Armenia | 10 |
| Greece | 3 |
| New Zealand | 9 |
| United States | 174 |
| Ukraine | 11 |
| Poland | 8 |
| Georgia | 10 |
| Australia | 5 |
| Belarus | 5 |
| Bulgaria | 3 |
| Russia | 50 |
| Canada | 1 |
| Turkey | 3 |
| Italy | 3 |
| Romania | 3 |
| Tanner Stage(Participants) | Lonapegsomatropin |
|---|---|
| Tanner Stage 1 | 214 |
| Tanner Stage 2 | 40 |
| Tanner Stage 3 | 25 |
| Tanner Stage 4 | 16 |
| Tanner Stage 5 | 3 |
| Height SDS(Height Standard Deviation Score) | Lonapegsomatropin |
|---|---|
| Mean | -1.564 ± 0.878 |
1 further baseline measures are reported on the registry.
PDFs hosted by the registry, ClinicalTrials.gov.
This study is completed, as verified in Jun 2026. You cannot join it, but the record below documents what was studied.
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Ascendis Pharma A/S