A Phase 3 interventional study of TransCon hGH in Growth Hormone Deficiency, Pediatric, Endocrine System Diseases and Hormone Deficiency, sponsored by Ascendis Pharma Endocrinology Division A/S. Completed at 24 sites in 4 countries. Open to participants aged 6 Months to 17 Years. Per ClinicalTrials.gov, last updated 2026-07-07.
Sponsored by Ascendis Pharma Endocrinology Division A/S · Phase 3, Interventional, and Treatment
A 26 week trial of TransCon hGH, a long-acting growth hormone product, administered once-a-week. Approximately 150 children (males and females) with growth hormone deficiency (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, Canada, Australia, and New Zealand.
6 months to 17 years old, inclusive, at Visit 1
Exclusion Criteria:
Once weekly subcutaneous injection of TransCon hGH
Drug: TransCon hGH
Once weekly subcutaneous injection at a starting dose of 0.24 mg/kg/week
Number of Participants With Treatment-Emergent Adverse Events [Safety and Tolerability]
Safety and tolerability of weekly lonapegsomatropin (TransCon hGH) treatment
Time frame: 26 weeks
Annualized Height Velocity (AHV) at 26 Weeks of Weekly Lonapegsomatropin Treatment
Annualized height velocity (AHV) at 26 weeks of weekly lonapegsomatropin (TransCon hGH) treatment. The AHV at each visit was modeled using ANCOVA adjusting for baseline age, peak GH levels (log transformed) at diagnosis, delta average-parental height SDS, prior GH dose level (log transformed), and prior GH dose duration (log transformed) as covariates and gender as a factor. Subjects who did not take prior GH treatment were not included in the model.
Time frame: 26 weeks
Number of Subjects With IGF-1 Standard Deviation Score (SDS) in the Range of 0.0 to +2.0 at 26 Weeks of Weekly Lonapegsomatropin Treatment
IGF-1 Standard Deviation Score (SDS) is the number of standard deviations above or below the mean Insulin-like Growth Factor 1 (IGF-1) level for age and sex. IGF-1 SDS was derived using the LMS method as ((IGF-1/M)\^L)-1)/(L x S), where M = median, S = generalized coefficient of variation, and L = power in the Box-Cox transformation, the M, S, L values were obtained from Bidlingmaier et al. (2014). A Standard Deviation Score of 0 represents the population mean.
Time frame: 26 weeks
Change in Height Standard Deviation Scores (SDS) at 26 Weeks of Weekly Lonapegsomatropin Treatment
Height Standard Deviation Score (SDS) is the number of standard deviations above or below the mean height for age and sex. Height SDS was derived using the LMS method as ((Height/M)\^L)-1)/(L x S), where M = median, S = generalized coefficient of variation, and L = power in the Box-Cox transformation, the M, S, L values were obtained from 2000 CDC growth charts for the United States. A Standard Deviation Score of 0 represents the population mean. A higher change from baseline in Height SDS indicates a better outcome. The height SDS change from baseline at each visit was modeled using ANCOVA adjusting for baseline age, peak GH levels (log transformed) at diagnosis, delta average-parental height SDS, prior GH dose level (log transformed), and prior GH dose duration (log transformed) as covariates and gender as a factor. Subjects who did not take prior GH treatment were not included in the model.
Time frame: Baseline and 26 weeks
Number of Participants With Treatment Emergent Anti-hGH Binding Antibody Formation
Number of participants with treatment emergent anti-hGH antibodies over 26 weeks of weekly lonapegsomatropin (TransCon hGH) treatment. All samples were negative for anti-hGH neutralizing antibodies.
Time frame: 26 weeks
| Milestone | Lonapegsomatropin |
|---|---|
| Started | 146 |
| Completed | 144 |
| Not completed | 2 |
| Withdrew: Withdrawal by subject | 2 |
Safety and tolerability of weekly lonapegsomatropin (TransCon hGH) treatment
| Participants | Lonapegsomatropin |
|---|---|
| TEAE | 83 |
| Related TEAE | 6 |
| Serious TEAE | 1 |
| Related Serious TEAE | 0 |
Annualized height velocity (AHV) at 26 weeks of weekly lonapegsomatropin (TransCon hGH) treatment. The AHV at each visit was modeled using ANCOVA adjusting for baseline age, peak GH levels (log transformed) at diagnosis, delta average-parental height SDS, prior GH dose level (log transformed), and prior GH dose duration (log transformed) as covariates and gender as a factor. Subjects who did not take prior GH treatment were not included in the model.
| cm/year | Lonapegsomatropin |
|---|---|
| Annualized Height Velocity (AHV) at 26 Weeks of Weekly Lonapegsomatropin Treatment | 8.72 ± 0.24 |
IGF-1 Standard Deviation Score (SDS) is the number of standard deviations above or below the mean Insulin-like Growth Factor 1 (IGF-1) level for age and sex. IGF-1 SDS was derived using the LMS method as ((IGF-1/M)\^L)-1)/(L x S), where M = median, S = generalized coefficient of variation, and L = power in the Box-Cox transformation, the M, S, L values were obtained from Bidlingmaier et al. (2014). A Standard Deviation Score of 0 represents the population mean.
| Participants | Lonapegsomatropin |
|---|---|
| Number of Subjects With IGF-1 Standard Deviation Score (SDS) in the Range of 0.0 to +2.0 at 26 Weeks of Weekly Lonapegsomatropin Treatment | 74 |
Height Standard Deviation Score (SDS) is the number of standard deviations above or below the mean height for age and sex. Height SDS was derived using the LMS method as ((Height/M)\^L)-1)/(L x S), where M = median, S = generalized coefficient of variation, and L = power in the Box-Cox transformation, the M, S, L values were obtained from 2000 CDC growth charts for the United States. A Standard Deviation Score of 0 represents the population mean. A higher change from baseline in Height SDS indicates a better outcome. The height SDS change from baseline at each visit was modeled using ANCOVA adjusting for baseline age, peak GH levels (log transformed) at diagnosis, delta average-parental height SDS, prior GH dose level (log transformed), and prior GH dose duration (log transformed) as covariates and gender as a factor. Subjects who did not take prior GH treatment were not included in the model.
| standard deviation score | Lonapegsomatropin |
|---|---|
| Change in Height Standard Deviation Scores (SDS) at 26 Weeks of Weekly Lonapegsomatropin Treatment | 0.25 ± 0.02 |
Number of participants with treatment emergent anti-hGH antibodies over 26 weeks of weekly lonapegsomatropin (TransCon hGH) treatment. All samples were negative for anti-hGH neutralizing antibodies.
| Participants | Lonapegsomatropin |
|---|---|
| Number of Participants With Treatment Emergent Anti-hGH Binding Antibody Formation | 4 |
Collected over 26 weeks. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Lonapegsomatropin | 0/146 (0%) | 1/146 (0.7%) | 65/146 (44.5%) |
| Event | Lonapegsomatropin |
|---|---|
| Atrioventricular blockCardiac disorders | 1/146 |
| Chest painGeneral disorders | 1/146 |
| Event | Lonapegsomatropin |
|---|---|
| PyrexiaGeneral disorders | 17/146 |
| NasopharyngitisInfections and infestations | 14/146 |
| Upper respiratory tract infectionInfections and infestations | 14/146 |
| HeadacheNervous system disorders | 12/146 |
| Oropharyngeal painRespiratory, thoracic and mediastinal disorders | 8/146 |
| Age, Continuous(years) | Lonapegsomatropin |
|---|---|
| Mean | 10.6 ± 3.9 |
| Age, Customized(Participants) | Lonapegsomatropin |
|---|---|
| Age, Categorical: — <3 years | 4 |
| Age, Categorical: — ≥3 and <6 years | 20 |
| Age, Categorical: — ≥6 to <11 years (girls) or ≥6 to <12 years (boys) | 55 |
| Age, Categorical: — ≥11 years (girls) or ≥12 years (boys) | 67 |
| Sex: Female, Male(Participants) | Lonapegsomatropin |
|---|---|
| Female | 36 |
| Male | 110 |
| Ethnicity (NIH/OMB)(Participants) | Lonapegsomatropin |
|---|---|
| Hispanic or Latino | 10 |
| Not Hispanic or Latino | 124 |
| Unknown or Not Reported | 12 |
| Race/Ethnicity, Customized(Participants) | Lonapegsomatropin |
|---|---|
| Race — Asian | 6 |
| Race — Black or African American | 3 |
| Race — Native Hawaiian or Other Pacific Islander | 2 |
| Race — White | 124 |
| Race — More than one race | 2 |
| Race — Unknown | 9 |
| Height(cm) | Lonapegsomatropin |
|---|---|
| Mean | 132.4 ± 22.5 |
| Height SDS(standard deviation score) | Lonapegsomatropin |
|---|---|
| Mean | -1.42 ± 0.84 |
| Weight(kg) | Lonapegsomatropin |
|---|---|
| Mean | 32.3 ± 14.2 |
2 further baseline measures are reported on the registry.
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Ascendis Pharma Endocrinology Division A/S