Neuroscience Institute

About the Fragile X Research Program at Children’s Hospital Colorado

Contact Info

Can my child participate in a research study?
If you are interested in learning more about these and other current research studies and seeing if your child is eligible for a research project, please call Susan Howell at 720-777-8361 or email susan.howell@childrenscolorado.org.


Fragile X Syndrome Research
(720) 777-8361


The Denver Fragile X Treatment and Research Center at the Child Development Unit is one of 26 clinics nationwide in the Fragile X Clinical and Research Consortium sponsored by the National Fragile X Foundation.  

Fragile X Research Program in the Neurosciences Institute

Clinics in the consortium provide individuals and families affected by fragile X-associated disorders with evaluation and care supported by the latest medical, educational and research knowledge available.  

The consortium is actively establishing “best practice” recommendations for evaluation and ongoing care of children with fragile X, enrolling fragile X families into a national registry to be used for research and research recruitment, and building a network for collaborative research efforts.

Learn more about fragile X syndrome, including its symptoms and treatment options.

Our current research efforts

At Children’s Colorado, we are currently recruiting subjects for the following fragile X studies:

Fragile X Registry

We are currently participating in a project with the consortium to build a registry of patients in order to collect clinical data over time and identify patients interested in participating in fragile X research.  In this project, patients with fragile X syndrome or with a fragile X gene mutation may  give permission to include their information in the national registry. We do not submit names to the registry, but we do include other information about the person  such as age, fragile X gene mutation status, other medical and psychological problems, and the types of projects the subject may be interested in participating in the future.  

The clinical data collected over time helps to establish best standards of care for patients with fragile X syndrome. In addition, researchers of fragile X syndrome can apply to view the registry information and contact our clinic if they would like to invite our patients to be a part of their research projects. In this case, our clinic contacts the patient, and asks if they would like for us to share their contact information with the researcher and have them contact the patient directly about the research project. Participation in projects is completely voluntary. If patients do not choose to participate, it does not affect the medical care provided by our clinic in any way. 

Fragile X Neuromotor Study

We are currently participating in a research project studying the motor skills (such as balance, coordination, reaction time and strength) of patients with fragile X syndrome between 5 and 39 years old. Our study aims to collect more information about neuromotor skills in boys and girls with fragile X syndrome of all ages, as well as find the best ways to measure neuromotor skills in people with fragile X syndrome.  

Participation in this study includes 1 to 5 visits to either the Fragile X Clinic at Children’s Hospital Colorado or Developmental FX (both located in Denver, Colorado). Each visit will include a variety of physical activities that measure things like balance, coordination and strength, as well as questionnaires and surveys to be completed by parents or caregivers and a few phone calls between visits to see how things are going during the study.  Participation is free, and you will be compensated for your time at each study visit.  The results of this study will help plan for future treatment studies in fragile X syndrome. 

Clinical Trial of Arbaclofen, sponsored by Seaside Therapeutics

We are currently conducting a research study to learn more about an investigational drug. We want to know if the investigational drug is safe and if it helps to treat symptoms of fragile X syndrome. We’re looking for volunteers ages 5 to 12 who have been diagnosed with fragile X syndrome and who have social difficulties (e.g. volunteers who often prefer to be alone, do not like being touched, do not react to other people in a socially appropriate manner, or have fixed facial expressions).  

About the study process
This study includes a total of 6 study visits to Children’s Hospital Colorado over the course of about 4 months. Most visits last 1-2 hours and the final visit may last up to 3 hours. A doctor speaks parents about how their child is doing during the visits. We check the child’s weight, height, pulse and blood pressure, and ask parents to answer some written questions. We also take blood sample from the child at 3 to 4 visits and do an ECG to check heart function during 2 visits. For each visit to the office, a small stipend is offered to offset travel expenses.

Benefits of participation
If you take part in this study, there may or may not be direct medical benefit to your child.  However, he or she will receive study-related medical care, monitoring and frequent visits with a study doctor. We provide information about fragile X syndrome and possible treatment options. This study may also help us learn to better care for others with fragile X syndrome in the future.

Clinical Trial of an mGluR5 Antagonist, sponsored by Roche Pharmaceuticals

We are currently conducting a research study to learn more about an experimental medication that is taken by mouth, called RO4917523, which is being developed for fragile X syndrome. We hope to learn about the medicine’s safety, how well the body tolerates it, how the medicine functions in the body, and if it helps the symptoms of fragile X syndrome. 

Who can participate? 
Anyone with fragile X syndrome who is between 16 and 50 years old can take part in this study. 

About the study process
Prior to doing any tests, the study doctor will ask you to sign a consent form. You (or your child) will need to attend 7 to 8 clinic visits (including the screening and follow-up visits) over the course of about 4 months. You will be given either RO4917523 or a placebo (also known as a “sugar pill”) during your participation in the study. On the weeks when you do not have a clinic visit, the study doctor or the research study staff will call to ask you a few questions about how you are feeling. If more tests are needed, the study doctor may ask you to schedule an additional study visit. 

Are there any expected benefits to taking part in this study?
Your (or your child’s) medical condition may improve from taking the study medication (RO4917523), although we cannot guarantee that there will be any benefit. By taking part in the study, you may help future participants by providing important information about RO4917523 and the treatment of fragile X syndrome. Participants who receive the placebo (the sugar pill, which does not contain the active ingredient) may not receive any benefit.

Learn more about fragile X syndrome.