NCT05849389

Brief Summary

Turner syndrome (TS) is characterized by a missing whole or part of the second sex chromosome in a phenotypic female, resulting in short stature due to haploinsufficiency of the short-stature homeobox-containing (SHOX) gene. Growth hormone (GH) is an approved therapy for this condition, although not associated with GH deficiency, and benefits are modest. Vosoritide, a C-type natriuretic peptide (CNP) analog, targets chondrocytes within the growth plate leading to increased cell proliferation and hypertrophy. We hypothesize that patients with TS and short stature will respond to vosoritide treatment leading to increased growth velocity. This study will enroll pre-pubertal girls with TS who are either naïve to GH or have had a poor response to GH therapy. All subjects will be treated with vosoritide for 12 months and will be assessed for safety monitoring and improvement in height outcomes. Annualized growth velocity (AGV) on vosoritide will be compared to AGV in the 6-18 months prior to initiation of vosoritide based on historical data available in the medical record. Subjects with a positive response to therapy will be given the option to continue in the extension phase of the study during which they will continue to receive vosoritide until growth cessation.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
20

participants targeted

Target at below P25 for phase_2

Timeline
4mo left

Started Apr 2024

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress87%
Apr 2024Sep 2026

First Submitted

Initial submission to the registry

April 28, 2023

Completed
10 days until next milestone

First Posted

Study publicly available on registry

May 8, 2023

Completed
11 months until next milestone

Study Start

First participant enrolled

April 12, 2024

Completed
2.4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

September 1, 2026

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

September 1, 2026

Last Updated

June 24, 2024

Status Verified

June 1, 2024

Enrollment Period

2.4 years

First QC Date

April 28, 2023

Last Update Submit

June 20, 2024

Conditions

Keywords

Turner syndromeShort StatureVosoritide

Outcome Measures

Primary Outcomes (3)

  • Incidence of treatment-emergent adverse events

    Number of treatment-emergent adverse events or serious adverse events per study participant

    12 months

  • Change from baseline in annualized growth velocity

    To evaluate the change from baseline in annualized growth velocity after 12 months of daily subcutaneous injections of vosoritide

    12 months

  • Change from baseline in age-sex standardized height standard deviation score

    To evaluate the change from baseline in age-sex standardized height standard deviation score (SDS) after 12 months of daily subcutaneous injections of vosoritide

    12 months

Secondary Outcomes (3)

  • Changes in seated height ratio

    12 months

  • Changes in arm span minus standing height

    12 months

  • Change in Bone Age

    12 months

Study Arms (1)

Vosoritide treatment arm

EXPERIMENTAL

Vosoritide will be administered daily via subcutaneous injection for 12 months using the FDA approved weight-based dosing band strategy for achondroplasia.

Drug: Vosoritide

Interventions

Vosoritide administered daily via subcutaneous injection for 12 months using the FDA approved weight-based dosing band strategy for achondroplasia.

Also known as: Voxzogo
Vosoritide treatment arm

Eligibility Criteria

Age3 Years - 11 Years
Sexfemale
Healthy VolunteersNo
Age GroupsChild (0-17)

You may qualify if:

  • Parent(s) or guardian(s) are willing and able to provide written, signed informed consent after the nature of the study has been explained and prior to performance of any research-related procedure. Also, subjects under the age of 18 are willing and able to provide assent (if required) after the nature of the study has been explained and prior to performance of any research-related procedure.
  • Stated willingness to comply with all study procedures and availability for the duration of the study
  • Age \>3 years 0 days AND \<10 years 364 days
  • Pre-pubertal defined as Tanner Stage 1 breasts in females.
  • Patient height \<-2 SDS. All height SDS values are calculated using the CDC growth charts/data tables.
  • Patients must have a confirmed diagnosis of Turner Syndrome based on a karyotype with a minimum of 30 cells or on a chromosomal microarray. Subjects with Turner Syndrome mosaicism (such as a 46,XX/45,X karyotype) must have a minimum of 10% mosaicism of 45,X cell line in order to participate in the study.
  • Subjects must either be naïve to growth hormone or have a poor response to growth hormone therapy defined as either:
  • Subjects completed at least one year of treatment with GH and first year height velocity (HV) below -1 SD according to the National Cooperative Growth Study TS 1st year response to growth hormone height velocity curve.
  • Subjects receiving GH for more than a year with AGV in the last 6 months \< 50%ile for US girls for age/sex). Subjects meeting this criterion are no longer showing catch up growth and may benefit from an alternative form of therapy.

You may not qualify if:

  • Growth plate fusion - Defined as a bone age via the Greulich and Pyle method of 13 years. These patients have limited remaining growth potential.
  • Concomitant treatment with growth hormone or recombinant insulin-like growth factor-1 (IGF-1). Patients may have been previously treated with growth hormone or IGF-1 therapy. If the patient is currently on one of these therapies, they will be required to discontinue at least 1 week prior to the screening visit. That decision will be deferred to their treating clinical endocrinologists in conjunction with the patient's guardians. We anticipate that only patients who are having a poor response to their therapy will be interested in enrolling in the current study as there is no rationale for a patient who is receiving growth hormone therapy and having a positive response to enroll in the current study.
  • Prior or concomitant treatment with any form of estrogen, gonadotropin-releasing hormone (GnRH) analog, aromatase inhibitor or oxandrolone
  • History of any type of malignancy
  • Subjects known to have Y-chromosome material unless they have undergone gonadectomy and have fully external female genitalia
  • Chronic medical condition known to affect growth including but not limited to:
  • A. Cystic fibrosis B. Diabetes C. Inflammatory Bowel Disease D. Untreated Celiac Disease - If a subject has been diagnosed with celiac disease and has been on a gluten free diet for \>12 months and has a tissue transglutaminase antibody within the normal range at screening, then they are eligible for the trial.
  • E. Asthma requiring a daily inhaled steroid dose \> 400 micrograms of inhaled budesonide per day or equivalent F. Taking daily oral glucocorticoids for any reason G. Note - Attention Deficit hyperactivity Disorder (ADHD) treated with a stimulant and treated hypothyroidism with a normal thyroid stimulating hormone (TSH) will NOT exclude the subject from participating in the trial. Subjects on either stimulant medication or thyroid hormone replacement must be on a stable dose for 3 months prior to the screening visit.
  • Malnutrition - Defined as a BMI \<5th percentile (CDC growth charts)
  • Any clinically significant abnormality on screening tests as determined by the principal investigator. Abnormal screening labs may be repeated up to 3 months after the screening visit. If those labs are normal on repeat, the subject may proceed into the trial.
  • Known or suspected allergy to trial medication, excipients, or related products
  • The receipt of any investigational drug within 90 days prior to this trial

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Children's National Hospital

Washington D.C., District of Columbia, 20010, United States

RECRUITING

MeSH Terms

Conditions

Turner SyndromeDwarfism

Interventions

vosoritide

Condition Hierarchy (Ancestors)

Gonadal DysgenesisDisorders of Sex DevelopmentUrogenital AbnormalitiesFemale Urogenital DiseasesFemale Urogenital Diseases and Pregnancy ComplicationsUrogenital DiseasesSex Chromosome Disorders of Sex DevelopmentMale Urogenital DiseasesHeart Defects, CongenitalCardiovascular AbnormalitiesCardiovascular DiseasesHeart DiseasesCongenital AbnormalitiesCongenital, Hereditary, and Neonatal Diseases and AbnormalitiesSex Chromosome DisordersChromosome DisordersGenetic Diseases, InbornGonadal DisordersEndocrine System DiseasesBone Diseases, DevelopmentalBone DiseasesMusculoskeletal Diseases

Study Officials

  • Roopa Kanakatti Shankar, MBBS, MS

    Children's National Research Institute

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Roopa Kanakatti Shankar, MBBS, MS

CONTACT

Study Design

Study Type
interventional
Phase
phase 2
Allocation
NA
Masking
NONE
Purpose
TREATMENT
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER
Responsible Party
SPONSOR INVESTIGATOR
PI Title
Director, Turner Syndrome Program

Study Record Dates

First Submitted

April 28, 2023

First Posted

May 8, 2023

Study Start

April 12, 2024

Primary Completion (Estimated)

September 1, 2026

Study Completion (Estimated)

September 1, 2026

Last Updated

June 24, 2024

Record last verified: 2024-06

Data Sharing

IPD Sharing
Will not share

Locations