This information was added in May 2026. We will endeavour to keep this up-to date to keep you posted on upcoming trials for HPP.
Introduction to hypophosphatasia (HPP)
Also known as HPP, Hypophosphatasia is a rare inherited metabolic condition caused by changes in a gene responsible for producing an enzyme called alkaline phosphatase. It is estimated to affect approximately 1 in 100,000 people in its more severe forms, although milder forms may be more common.
But what does that mean?
Our bones and teeth are constantly developing and repairing. For them to become strong and hard, the body needs to carefully control minerals such as calcium and phosphate. One of the key helpers in this process is an enzyme called alkaline phosphatase. You can think of enzymes as tiny tools that help important chemical reactions happen in the body.
Alkaline phosphatase plays an essential role in bone mineralisation. This is the process that allows minerals to bind properly to bones and teeth, making them firm and strong.
In hypophosphatasia, the body does not produce enough working alkaline phosphatase. As a result, certain natural chemicals build up and prevent minerals from being laid down properly in the bones. This means bones can become soft and weak, a problem known as poor mineralisation.
Because of this, babies with severe forms of HPP may be born with very soft bones. In milder forms, children or adults may experience symptoms such as:
- Early loss of baby teeth
- Bone pain
- Frequent fractures
- Delayed walking
- Muscle weakness
The severity of HPP can vary widely. Some people are diagnosed before birth or in infancy, whilst others may not be diagnosed until adulthood.
Diagnosis and Management
Hypophosphatasia is often suspected when blood tests show persistently low levels of alkaline phosphatase, which is unusual because levels are typically higher during childhood. Diagnosis can be confirmed through genetic testing to identify changes in the ALPL gene.
Management depends on the severity of the condition. Care may include monitoring bone health, managing pain, physiotherapy, and dental support. In more severe cases, enzyme replacement therapy may be offered to help improve bone mineralisation.
Early diagnosis and specialist care are important to help reduce complications and improve quality of life.
Upcoming trials for people living with HPP
We have received information from a company with a clinical trial focusing on hypophosphatasia (HPP). At present, we only have one trial listed but will work to obtain further trial information.
Click the button underneath the trial to learn more and to get involved:
Alesta Therapeutics: Study ALE1-101
Alesta Therapeutics is conducting a clinical study and looking for volunteers in the UK with HPP to test an experimental drug called ALE1. ALE1 is designed to decrease the build-up of a substance called inorganic pyrophosphate (PPi) in patients with HPP.
The current study aims to measure the safety of ALE1, the amount of ALE1 in the blood, and its effect on the body. Where appropriate, and after discussion with your physician, participants who successfully complete any of the Alesta studies may be considered for participation in later trials.
Find out more and get involved:
A note from Metabolic Support
We hope this page has been helpful and has provided you with an insight into trial information for HPP. Although clinical trials must gain approvals and follow strict regulations and processes to ensure safety, all clinical trials carry some degree of risk.
If you do have an interest in participating in a clinical trial it is important you gather all information available. You can discuss this with your consultant or the lead investigator of a trial who’ll be happy to provide more information and help you make an informed decision without committing to participating.
