A New
Opportunity to Help Manage Your Child’s HPP
If your child is living with hypophosphatasia (HPP), the Chestnut Study may be an option.
We are currently enrolling 40 children ages two to 12 with HPP to take part in a clinical research study.
Eligible participants must:
- Be two to 12 years of age
- Have a documented diagnosis of HPP
- Have received STRENSIQ®
- NOT have any new fracture within 12 weeks before first dose (excluding pseudofractures)
There are additional eligibility criteria, which the study team will discuss with you.
About the Chestnut Study
The purpose of this study is to evaluate the safety and effectiveness of an investigational medication in children with HPP who have received treatment with STRENSIQ.
Those who are eligible to participate and who decide to enroll will initially be randomly assigned to receive the investigational medication or STRENSIQ. For every one participant who receives the investigational medication, one participant will receive STRENSIQ. After a certain point in the study, all participants will receive the investigational medication.
Find a participating site
The Chestnut Study may last up to approximately three years, and it consists of four periods:
Screening
During this 30-day period, the study team will determine study eligibility.
Randomized Evaluation
This will last approximately six months, during which participants are randomized 1:1 to receive either the investigational medication or STRENSIQ. Participants will attend eight visits and receive their assigned study treatment during visits and at home.
Open-Label Extension (OLE)
Participants are eligible to join this two-part OLE period to continue (or start, if they were previously assigned to STRENSIQ) receiving the investigational medication for up to an additional two and a half years.
- Part A will have five visits over approximately six months
- Part B will have three visits (one every nine months) for a little over two years
Safety Follow-Up
After completing the OLE period, or if a participant withdraws from the study early, they will enter a four-week safety follow-up period with up to two visits to have their health monitored after they stop receiving the assigned study treatment.
Both the investigational medication and STRENSIQ are administered as injections. The investigational medication will be given once every two weeks, and STRENSIQ will be given as 6 mg per week, either 2 mg three times per week or 1 mg six times per week. All study participants will receive the assigned study treatment, study-related medical exams, and study-related laboratory tests at no cost. Support to cover study-related travel costs may be available.
About Hypophosphatasia
Hypophosphatasia (HPP) is a very rare genetic disorder. People with this condition have low levels of an enzyme called alkaline phosphatase (ALP), which affects the development of bones and teeth. Symptoms vary greatly from person to person, and some individuals may not have symptoms at all.
Common symptoms may include but are not limited to:
- Abnormality of ribs, teeth, or other bones
- Premature closure of cranial sutures
- Shortness of breath
- Difficulty feeding in infancy
- Mobility challenges
- Failure to thrive
- Skin dimples
- Anemia
- Muscle pain/fatigue
- Joint pain/swelling
- Recurrent bone fractures
- Seizures1
Diagnosis of HPP may occur at any age and be different based on what symptoms, if any, are present. Testing may include x-rays or lab tests to measure the activity of ALP in the blood. Prenatal testing and ultrasounds may also be done during pregnancy.
Reference
- rarediseases.info.nih.gov/diseases/6734/hypophosphatasia↵
What You Should Know about Clinical Research Studies
Clinical research studies look at an investigational medication, medical device, or procedure to see if it is safe, how it affects the body, and if it works to treat a specific disease. Clinical research studies are conducted by doctors who are responsible for the study participants’ study-related care.
In most countries, the regulatory health authority requires that several phases of clinical research be performed to better understand the safety and effectiveness of new study medications and certain medical devices and procedures.
Clinical research studies must be reviewed by an institutional review board (IRB) or ethics committee (EC). An IRB/EC is an independent group that is responsible for helping to protect the rights and well-being of study participants. In addition, every study participant is monitored with study-related medical tests and exams before, during, and sometimes even after the study.
Participation in any clinical research study is completely voluntary, and you may choose to withdraw your child from the study at any time for any reason. If you would like your child to leave the study, you should discuss this with your child’s study doctor, who will give you information about how to do this safely.
Throughout the study, the study team will perform tests and procedures to check on your child’s health. These tests and procedures include vital sign measurements (such as blood pressure and temperature), physical exams, height and weight measurements, blood and urine sample collections for lab tests, heart tests such as electrocardiograms (ECGs), x-rays, mobility assessments, questionnaires on how your child is feeling, and other assessments.
Participation in the Chestnut Study may last up to approximately three years. This includes a screening period, a randomized evaluation period, an open-label extension period, and a safety follow-up period.