Study of Psychological and Motor Effects of Testosterone in Adolescents With XXY/Klinefelter Syndrome (TestoXXY/KS)
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ClinicalTrials.gov Identifier: NCT01585831 |
Recruitment Status :
Completed
First Posted : April 26, 2012
Results First Posted : August 10, 2021
Last Update Posted : August 10, 2021
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Condition or disease | Intervention/treatment | Phase |
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Klinefelter Syndrome XXY Syndrome | Drug: Testosterone gel 1% Drug: Placebo gel | Not Applicable |
Klinefelter syndrome (47,XXY) is the most common chromosomal abnormality in humans and occurs in approximately 1 in 650 males. Testosterone deficiency develops during adolescence in the majority of individuals with XXY. However, there are no previous studies that evaluate the psychological and motor effects of testosterone replacement therapy in adolescents with XXY.
The study researchers are interested in learning if testosterone therapy initiated in early puberty in XXY (KS) will lead to improvements in psychological and/or motor skills. They are also interested in learning if genetic variations of the androgen receptor gene or the parent-of-origin of the extra X chromosome influence the response to testosterone therapy.
Specific psychological factors to be studied include verbal and nonverbal cognitive skills, attention, executive function (organization, problem-solving skills, inhibition), anxiety, language, self-esteem, and other behavioral factors. Motor skills to be studied include gross and fine motor skills, motor coordination, and motor planning.
Participants in the study will be randomized to one of two treatment groups, receiving either testosterone gel or placebo, for 12 months. 60% of the study group will receive testosterone, and 40% will receive placebo.
The research participants, parents/caregivers, and the members of the study team will be blinded to the treatment group, and will not know whether they are receiving testosterone gel or placebo treatments.
The supervising endocrinologist for the study will not be blinded and will know which patients are in the testosterone and placebo groups. This will allow him to monitor results to determine if participants in the placebo group may develop a significant need for testosterone therapy during the study period. If this occurs, the patient will be switched to the testosterone group and will continue to be monitored in the study.
All participants will be evaluated at the beginning of the study and at 1, 3, 6, and 12 months. Travel costs are included. Evaluations will include a combination of psychological and motor skills testing, questionnaires completed by the parent/caregiver and study participant, physical examinations, and blood draws for safety monitoring and genetic studies.
Participation in the trial will last one year and includes 5 clinic visits to the eXtraordinarY Kids Clinic at Children's Hospital Colorado in Denver.
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 48 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Triple (Participant, Care Provider, Investigator) |
Primary Purpose: | Treatment |
Official Title: | Psychological and Motor Effects of Testosterone Therapy in Adolescents With XXY/Klinefelter Syndrome |
Study Start Date : | March 2012 |
Actual Primary Completion Date : | October 2017 |
Actual Study Completion Date : | October 2017 |

Arm | Intervention/treatment |
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Experimental: Testosterone gel 1%
Testosterone gel 1% applied to skin once per day for 1 year. Starting dose 1.25mL per day, titrated in 1.25mL increments for 1st 6 months of study after each study visit up to maximum of 5.0mL per day. Titration based on testosterone levels with target level in mid-range of normal for Tanner stage.
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Drug: Testosterone gel 1%
Testosterone gel will be administered on a daily basis. The gel will be dispensed in a syringe, and the specific amount of gel to be applied each day will be determined by the study endocrinologist after reviewing labs.
Other Name: Androgel 1% |
Placebo Comparator: Placebo gel
Placebo gel applied to skin once per day for 1 year. Starting dose 1.25mL per day. Dose randomly adjusted in 1.25mL increments for 1st 6 months of study after each study visit up to maximum of 5.0mL per day.
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Drug: Placebo gel
The placebo gel will be administered on a daily basis. The gel will be dispensed in a syringe, and the specific amount of gel to be applied each day will be determined by the study endocrinologist. |
- Change From Baseline on the Delis-Kaplan Executive Function System [ Time Frame: Visit 1 (baseline) and Visit 5 (1 year) ]A collection of subtests from the Delis-Kaplan Executive Function System will be used to evaluate different domains of executive functions including planning, problem solving, fluency, inhibition, and working memory. Possible scaled scores range from 0-20 (mean of 10), with higher scores indicating better performance. The value of the change in scaled score from baseline is reported.
- Change From Baseline on the Bruininks-Oseretsky Test of Motor Development - 2 [ Time Frame: Visit 1 (baseline) and Visit 5 (1 year) ]This test evaluates many aspects of motor functioning including fine and gross motor skills, visual motor integration, motor planning, and motor coordination. Possible scores range from 20-80, with higher scores indicating a better outcome.
- Change From Baseline on the Conners Parent Rating Scales: DSM Attention [ Time Frame: Visit 1 (baseline) and Visit 5 (1 year) ]This questionnaire allows parents to rate many aspects of behavior including attention, hyperactivity, anxiety, social skills, and emotional lability. The range of possible scores is 0 to 100 (Mean T-score 50), with higher scores indicating a worse outcome.
- Change From Baseline on the Conners Parent Rating Scales: DSM Hyperactivity [ Time Frame: Visit 1 (baseline) and Visit 5 (1 year) ]This questionnaire allows parents to rate many aspects of behavior including attention, hyperactivity, anxiety, social skills, and emotional lability. The range of possible scores is 0 to 100 (Mean T-score 50), with higher scores indicating a worse outcome.
- Change From Baseline on the Conners Parent Rating Scales: Anxiety [ Time Frame: Visit 1 (baseline) and Visit 5 (1 year) ]This questionnaire allows parents to rate many aspects of behavior including attention, hyperactivity, anxiety, social skills, and emotional lability. The range of possible scores is 0 to 100 (Mean T-score 50), with higher scores indicating a worse outcome.
- Change From Baseline on the Conners Parent Rating Scales: Social Skills [ Time Frame: Visit 1 (baseline) and Visit 5 (1 year) ]This questionnaire allows parents to rate many aspects of behavior including attention, hyperactivity, anxiety, social skills, and emotional lability. The range of possible scores is 0 to 100, with higher scores indicating a worse outcome.
- Change From Baseline on the Conners Parent Rating Scales: Emotional Lability [ Time Frame: Visit 1 (baseline) and Visit 5 (1 year) ]This questionnaire allows parents to rate many aspects of behavior including attention, hyperactivity, anxiety, social skills, and emotional lability. The range of possible scores is 0 to 100, with higher scores indicating a worse outcome.
- Change From Baseline on the Vineland Adaptive Behavior Scales - 2nd Edition [ Time Frame: Visit 1 (baseline) and Visit 5 (1 year) ]The Vineland-2 is an interview evaluating adaptive skills in the areas of communication, daily living skills, social skills, and motor skills. Possible scores range from 20 to 160 (mean 100), with higher scores indicating a better outcome.
- Change From Baseline on the Wechsler Intelligence Scale for Children - Fourth Edition [ Time Frame: Visit 1 (baseline) and Visit 5 (1 year) ]This standardized assessment of cognitive functioning allows for evaluation of verbal and nonverbal cognitive skills, working memory, and processing speed. Possible full scale IQ scores range from 40-180 (mean 100), with higher scores indicating a better outcome.
- Change From Baseline on the Comprehensive Test of Phonological Processing [ Time Frame: Visit 1 (baseline) and Visit 5 (1 year) ]This standardized test evaluates reading and language skills. Possible scores range from 20-200 (Mean Standard Score 100), with higher scores indicating a better outcome.

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Ages Eligible for Study: | 8 Years to 18 Years (Child, Adult) |
Sexes Eligible for Study: | Male |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Males with 47,XXY
- Participants must be in early puberty (Tanner stage II-III)
- Age 8 - 18 will be considered, but eligibility will be determined by review of laboratory results, bone age X-ray, and physical examination to determine stage of puberty
- All racial and ethnic groups
Exclusion Criteria:
- Other genetic variations of Klinefelter syndrome (48,XXXY, 48,XXYY, 49,XXXXY). The investigator has other studies for these groups and we encourage interested individuals with these disorders to contact us about other available studies.
- 47,XXY plus another genetic disorder
- Non-English speaking individuals (because the psychological tests are administered in English)
- Participants with a medical history of blood clotting problems, blindness, deafness, or cancer

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01585831
United States, Colorado | |
Childrens Hospital Colorado | |
Aurora, Colorado, United States, 80045 |
Principal Investigator: | Nicole Tartaglia, MD | University of Colorado School of Medicine |
Documents provided by University of Colorado, Denver:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: | University of Colorado, Denver |
ClinicalTrials.gov Identifier: | NCT01585831 |
Other Study ID Numbers: |
11-0874 1K23NS070337 ( U.S. NIH Grant/Contract ) |
First Posted: | April 26, 2012 Key Record Dates |
Results First Posted: | August 10, 2021 |
Last Update Posted: | August 10, 2021 |
Last Verified: | July 2021 |
Klinefelter syndrome XXY syndrome Sex Chromosome Abnormality Testosterone replacement therapy |
Klinefelter Syndrome Syndrome Disease Pathologic Processes Sex Chromosome Disorders of Sex Development Disorders of Sex Development Urogenital Abnormalities Female Urogenital Diseases Female Urogenital Diseases and Pregnancy Complications Urogenital Diseases Male Urogenital Diseases Sex Chromosome Disorders |
Chromosome Disorders Congenital Abnormalities Genetic Diseases, Inborn Gonadal Disorders Endocrine System Diseases Hypogonadism Testosterone Androgens Hormones Hormones, Hormone Substitutes, and Hormone Antagonists Physiological Effects of Drugs |