52 Week Study + 24-Month Long-Term Extension of Safety, PK, & Efficacy of XYOSTED® for Testosterone Replacement in Male Adolescents With Hypogonadism
Open-Label, Multiple-Dose, 52-Week Study + 24-Month Long-Term Safety Extension to Evaluate the Safety, PK, & Efficacy of XYOSTED® for Testosterone Replacement in Male Adolescents With Deficiency or Absence of Endogenous Testosterone Due to Primary or Secondary Hypogonadism
1 other identifier
interventional
100
1 country
20
Brief Summary
This is a 52-week open label single arm study + 24-Month long-term safety extension to investigate the effects of XYOSTED, as testosterone replacement therapy, on adolescent males with either primary or secondary hypogonadism. The study aims to determine the effectiveness of XYOSTED measured by continuation or induction of puberty in addition to XYOSTED dosage, safety and testosterone levels.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P25-P50 for phase_3
Started Mar 2025
Longer than P75 for phase_3
20 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
November 6, 2024
CompletedFirst Posted
Study publicly available on registry
November 14, 2024
CompletedStudy Start
First participant enrolled
March 7, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
March 1, 2028
ExpectedStudy Completion
Last participant's last visit for all outcomes
March 1, 2030
February 18, 2026
February 1, 2026
3 years
November 6, 2024
February 16, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Increase in testosterone, as evaluated using PK parameters
From Enrollment through End of Study Assessments at Week 53
Secondary Outcomes (7)
Percentage of participants demonstrating either progression through Tanner Stages of puberty or attainment of Tanner Stage 5 by the end of the study
End of Study Assessment at Week 53
• Percentage of patients that had an increase in stretched penile length
End of Study Assessment at Week 53
Change from Screening or Baseline in DEXA bone density for total body less head (TBLH) and PA spine
End of Study Assessment at Week 53
Change from Screening or Baseline in body composition by DEXA scan
End of Study Assessment at Week 53
Change from Screening or Baseline in bone age as determined by X-ray
End of Study Assessment at Week 53
- +2 more secondary outcomes
Other Outcomes (2)
PK endpoints
End of Study Assessment at Week 53
Evaluation of Safety Endpoints including Treatment-Emergent Adverse Events
End of Study Assessment at Week 53
Study Arms (1)
Participants
EXPERIMENTALXYOSTED Injection (Testosterone enanthate) 25 mg / 0.5 mL, 50 mg / 0.5 mL, 75 mg / 0.5 mL, 100 mg / 0.5 mL
Interventions
XYOSTED 25 mg / 0.5 mL; XYOSTED 50 mg / 0.5 mL; XYOSTED 75 mg / 0.5 mL; XYOSTED 100 mg / 0.5 mL
Eligibility Criteria
You may qualify if:
- Diagnosed with a deficiency or absence of endogenous testosterone due to primary or secondary hypogonadism of a known etiology. Children with combined hormone deficiencies are permitted to enroll (but the child must already be receiving treatment for concomitant hormonal deficiencies)
- Participants receiving prior testosterone treatment must be receiving a stable dose for at least 12 weeks prior to Screening. Treatment naive participants are permitted to enroll.
- Have parent(s) or a legal guardian who will voluntarily provide written informed consent for the child to participate in the study
- Willing to provide assent for participation in the study
- Be a male 12 to \< 18 years of age at the time of consent/assent
- Have Legally Authorized Representative who is able to understand and comply with all study procedures and agrees to have the child participate in the study program as outlined in the protocol
- Requires chronic pharmacologic support for the initiation and/or continuation of pubertal maturation
- Have a body mass index (BMI)-for-age greater than the 5th percentile and weigh ≥ 30 kg.
- If sexually active with a female partner of child-bearing potential, agrees to:
- Practice true abstinence including 30 days after the last IP administration, or,
- Use 2 adequate forms of highly effective contraception, one of which should be a physical barrier, during the study and for 30 days after the last IP administration.
You may not qualify if:
- Has abnormal thyroid function tests at Screening. May supplement per usual clinical practice and rescreen up to two times.
- Has suspected or known constitutional growth delay in growth and puberty (CDGP)
- Has evidence of possible nutritional or gastrointestinal disorder that may impact growth (e.g., abrupt weight loss within the 3 months prior to Screening, unmanaged celiac disease, inflammatory bowel disease)
- Has a known allergy or hypersensitivity to XYOSTED, or to any of its ingredients (testosterone enanthate and sesame oil)
- Participants receiving prior treatment with testosterone who are not on a stable dose for at least 12 weeks prior to Screening.
- Has an allergy to foods or products containing sesame seeds or sesame oil
- Has Stage 1 hypertension, defined as the average of 2 or more seated right arm BP measurements exceeding the 95th percentile for age, sex, and height, or SBP ≥ 130 mm Hg and/or DBP ≥ 80 mm Hg at Screening or Day 1.
- Has a clinically significant abnormal clinical laboratory test value at Screening, as determined by the Investigator including hematocrit \> 48%, or \>50% for patients living at high altitude if not receiving testosterone treatment, or hematocrit \> 52% if already receiving testosterone treatment.
- Has a history of deep venous thrombosis or pulmonary embolism
- Has evidence of a clinically significant 12-lead electrocardiogram (ECG) abnormality at Screening, as determined by the Investigator
- Has a current suspected or diagnosed (and unresected) tumor of the pituitary gland with the exception of Rathke's cleft cyst or a stable non-functioning pituitary microadenoma (ie, lesion size \< 10 mm that has not increased in size over a period of 1 year on repeat imaging), as determined by the Investigator
- Has an active malignancy or has received treatment for a malignancy within the 12 months before Screening
- Is currently receiving antipsychotic medication for any reason or is currently receiving selective serotonin reuptake inhibitor (SSRI) medication for depression
- Is receiving any other medication or has a condition that would preclude safe participation in the study or confound the evaluation of safety, as determined by the Investigator
- Has a history of suicidal behavior (i.e., actions intended to harm oneself), suicidal ideation (i.e., thoughts and plans about suicide), or suicide attempts
- +9 more criteria
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (20)
Children's Hospital Los Angeles
Los Angeles, California, 90027, United States
Rady Children's Hospital - San Diego
San Diego, California, 92123, United States
University of California San Francisco
San Francisco, California, 94143, United States
Children's Hospital Colorado
Aurora, Colorado, 80045, United States
Nemours Children's Specialty Care - Jacksonville
Jacksonville, Florida, 32207, United States
Ann & Robert H. Lurie Children's Hospital of Chicago
Chicago, Illinois, 60611, United States
Boston Children's Hospital
Boston, Massachusetts, 02115, United States
University of Massachusetts Memorial Medical Center
Worcester, Massachusetts, 01655, United States
M Health Fairview U Minnesota
Minneapolis, Minnesota, 55454, United States
Washington University School of Medicine in St. Louis
St Louis, Missouri, 63110, United States
The DOCS
Las Vegas, Nevada, 89113, United States
Children's Hospital at Montefiore
The Bronx, New York, 10467, United States
OUHSC Pediatric Diabetes & Endocrinology
Oklahoma City, Oklahoma, 73104, United States
Children's Hospital of Philadelphia
Philadelphia, Pennsylvania, 19104, United States
Prisma Health Children's Hospital - Midlands
Columbia, South Carolina, 29203, United States
MedResearch
El Paso, Texas, 79902, United States
Texas Children's Hospital
Houston, Texas, 77030, United States
Primary Children's Hospital
Salt Lake City, Utah, 84112, United States
Seattle Children's Hospital
Seattle, Washington, 98105, United States
MultiCare Institute for Research & Innovation
Tacoma, Washington, 98405, United States
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Intervention Hierarchy (Ancestors)
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 3
- Allocation
- NA
- Masking
- NONE
- Purpose
- TREATMENT
- Intervention Model
- SINGLE GROUP
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
November 6, 2024
First Posted
November 14, 2024
Study Start
March 7, 2025
Primary Completion (Estimated)
March 1, 2028
Study Completion (Estimated)
March 1, 2030
Last Updated
February 18, 2026
Record last verified: 2026-02