Do You Have Cerebrotendinous Xanthomatosis (CTX)?

Participate in a study looking at ways to help slow the impact of CTX

Learn more

About the RESTORE Study

What is the RESTORE study?

The RESTORE study is a Phase 3 clinical trial looking at an investigational medication called chenodeoxycholic acid (also called Chenodal™, or CDCA). We are inviting people with Cerebrotendinous Xanthomatosis (CTX) who may be interested in participating in a research study.

The RESTORE study is enrolling pediatric (1 month to 16 years old) and adult (16 years and older) participants throughout the United States. The study will last approximately 6-7 months and involve about 18 visits to a study center. If the study is right for you and you choose to participate, all study-related care and study medication will be provided at no cost during your participation.

About Cerebrotendinous Xanthomatosis (CTX)

CTX is a rare, progressive, and underdiagnosed bile acid synthesis disorder affecting many parts of the body. Patients with CTX have a genetic mutation that prevents their body from making CDCA. As a result, the body is unable to break down cholesterol properly causing toxins (e.g., cholestanol and bile alcohols) to build up throughout the body over time. In CTX, cholestanol builds up in the eyes, tendons (i.e., tissues that connect muscle to the bone), brain, and other tissues and can cause a number of different problems throughout a patient’s life.

The investigational medicine in the RESTORE study, CDCA, is a bile acid replacement therapy that is recognized as a potential treatment for CTX1,2; however, it has not been approved by the U.S. Food and Drug Administration (FDA) for use in CTX in the United States. CDCA is approved in the United States as Chenodal™ for the treatment of a certain type of gallstones.3

The goal of the RESTORE study is to better understand how the body responds, as measured in blood and urine, when people with CTX use CDCA. It will also help the sponsor (Travere Therapeutics, Inc.) learn more about the safety of CDCA, or what side effects, if any, appear with CDCA use. For the purposes of the RESTORE study, CDCA is considered to be an investigational study drug.

What to expect

Eligible participants (pediatric and adult) will need to visit a study center about 18 times. There will also be times when participants, or their caregivers, will need to speak by telephone to the study team at a study center. The study will last approximately 25 to 28 weeks (6-7 months).

In the Adult Group (16 years and older), participants will receive, at different times, CDCA or placebo (a substance that looks like CDCA but does not contain any active CDCA) to compare how the body responds. Both of these study medications will be given as tablets that need to be taken 3 times daily by mouth.

In the Pediatric Group (1 month to 16 years old), all participants will receive CDCA (there will be no placebo). The study medication will be given in liquid form that will need to be taken 3 times daily by mouth.

In both the Adult and Pediatric Groups, several tests and assessments will be performed to monitor the participant’s health. These will include:

Measuring your blood pressure, heart rate, breathing rate, and temperature
Checking the medications you are currently taking
Completing physical examinations
Blood and urine collection and testing
Performing electrocardiograms (ECG) and electroencephalograms (EEG) to check the activity of your heart and brain, respectively
Other tests including:
  • Eye exam
  • Health questionnaires
  • Pregnancy test, if applicable

The study periods

The RESTORE Study consists of 6 study periods for adults and 4 study periods for pediatrics. See below for more details.

Adult Group

1
Screening period
Lasts up to 28 days
To determine if the study is right for you and if you qualify
2
Treatment period #1
8 weeks
You will take CDCA by mouth three times every day
3
Treatment period #2
4 weeks
You will take either CDCA or placebo three times every day; you and the study team will be “blinded” from knowing which medication you are taking
4
Treatment period #3
8 weeks
You will take CDCA by mouth three times every day
5
Treatment period #4
4 weeks
You will take either CDCA or placebo three times every. This medication assignment will be different from what you took during Treatment period #2. You and the study team will still not know which medication you are taking
6
End of study phone call
Approximately 30 days after taking your last dose of study medication
You will receive a phone call from the study center for an end of study session
Study Design for Adults

Pediatric Group

1
Screening period
Lasts up to 28 days
To determine if the study is right for you*
2
Treatment period #1
8 weeks
You will take liquid CDCA by mouth three times every day. The study team will determine the best dose of CDCA for you*.
3
Treatment period #2
16 weeks
You* will take liquid CDCA by mouth three times every day
4
End of study phone call
Approximately 30 days after completing Treatment period #2
You* will receive a phone call from the study center for an end of study session
Study Design for Pediatric Group (children and teenagers under 16 years of age)
*If you are reviewing these details on behalf of a child under the age of 16 years, the word "you" refers to the child

Who Can Take Part?

You* may be eligible to participate in the RESTORE study if you meet the following:

  • Have a clinical diagnosis of CTX (presence of symptoms) with supporting laboratory results (for example, increased cholestanol and bile alcohols in blood or urine)
  • At least 1 month old at the time of screening
  • Participants of childbearing potential must agree to use reliable birth control throughout the study

You must meet all other study criteria to take part in the RESTORE study. The full list of eligibility criteria is available at clinicaltrials.gov.

Email medinfo@travere.com for more information!

*If you are reviewing these details on behalf of a child under the age of 16 years, the word "you" refers to the child

** Any personal data you provide Travere Therapeutics will be processed according to our Privacy Policies.

Study Locations

About Clinical Trials

Before regulatory authorities, responsible for approving medicines for use in each country, can consider an investigational drug, device or procedure for approval, it must be shown to be both safe and to work well. Typically, this is accomplished through clinical trials — carefully designed, controlled and monitored studies intended to test and evaluate these investigational drugs, devices or procedures.

People may be interested in clinical trials for a variety of reasons. Some people participate in clinical trials as a way to contribute to medical science and to help doctors and researchers find other ways to help patients. Others participate in clinical trials to receive investigational drugs because their illness is not responding to standard treatment. Their hope is that the study drug — possibly an investigational drug or an investigational combination of drugs — will work for them. This will not always be the case, because some investigational drug regimens may not work or may have unexpected side effects. For this reason, everyone who participates in a clinical trial is carefully monitored. Frequent study-related medical exams and tests may need to be performed to help monitor the participants’ safety.

Clinical trials are divided into different phases. Each phase is designed to collect specific information about the study drug or regimen.

Phase 1 trials
The first human tests of investigational drugs or drug regimens occur in Phase 1 trials. Phase 1 trials are designed to determine the best dose of the study drug and to check for any potential side effects. These trials usually involve small numbers of participants. Because Phase 1 trials use study drugs that have never been tested in humans, they may involve significant risks. For Phase 1 trials, participants will often be compensated for the time spent in the study and possibly for travel expenses to the testing facility.
Phase 2 trials
Phase 2 trials are designed to see how well the study drug works in patients with the target disease being studied, usually in a larger group of participants, and to confirm the safety data established in the Phase 1 trial.
Phase 3 trials
Phase 3 trials test the safety and how well the study drug works in hundreds or even many thousands of participants. Phase 3 clinical trials often compare the study drug to a placebo (inactive drug) or an existing standard treatment in a randomized fashion. Participants in a randomized trial have a chance to receive the investigational drug but also have a chance to receive the comparator which could be a placebo (inactive) or the existing standard of care. The RESTORE study is in Phase 3.
Phase 4 trials

Phase 4 trials are conducted after the Regulatory Authorities have approved a drug and after the drug is on the market. Phase 4 trials typically involve a large number of participants. They may evaluate new uses of existing therapies or be used to detect side effects that did not appear during Phase 3 or earlier clinical trials and do not involve a placebo group.

For more information on clinical trials, please visit travere.com.

Talk to Your Doctor

Download the appropriate brochure based on the age of the person with CTX to share with your doctor to see if the RESTORE study is right for you.

REFERENCES: 1. Mignarri A, Gallus GN, Dotti MT, Federico A. A suspicion index for early diagnosis and treatment of cerebrotendinous xanthomatosis. J Inherit Metab Dis. 2014;37(3):421-429. 2. National Organization for Rare Disorders. Rare Disease Database: Cerebrotendinous xanthomatosis. https://rarediseases.org/rare-diseases/cerebrotendinous-xanthomatosis/ Accessed April 26, 2020. 3. CHENODAL [package insert]. Fort Collins, CO: Manchester Pharmaceuticals, Inc; 2009.