A study testing the safety and effectiveness of infigratinib compared to placebo in infants and young children with achondroplasia

2 1 1

What is this study about?

This study is looking at achondroplasia, which is a genetic condition that affects bone growth and is the most common cause of short stature. The study will test a medication called infigratinib, which is also known by its code names BGJ398 or BBP-831. This medication comes in tablet form and is taken by mouth. Some participants will receive infigratinib while others will receive placebo during certain parts of the study.

The purpose of the study is to find out if infigratinib is safe and works well in babies and young children with achondroplasia who are younger than three years old. The study is divided into several parts. The first part will test different single doses of the medication to find the right dose to use in later parts. The next part will confirm that the chosen doses are safe and will check how the medication moves through the body. The main part of the study will compare infigratinib to placebo over a period of time to see how well it works and whether it is safe. After completing the main part, children can continue in an extension part of the study until they reach three years of age.

During the study, children will be checked regularly for any side effects and changes in their health. Doctors will measure body length and compare it to growth charts made specifically for children with achondroplasia. They will also measure the ratio between the upper and lower parts of the body, head size compared to body length, and will check bone development using x-rays. Some children will have an MRI scan to look at skull and brain shape. The study team will track when the soft spots on the head close, monitor sleep problems, check if any surgeries are needed, and assess the child’s development of movement, language, thinking, and social skills. Parents or guardians will also answer questions about the child’s quality of life.

1 Initial treatment period

The child will begin receiving the assigned study medication, which is infigratinib in tablet form taken by mouth. The medication is designed to treat achondroplasia, a condition affecting bone growth.

The child may receive either the active medication or a placebo, which is an inactive substance that looks like the medication but contains no active ingredient. This is determined randomly in the double-blind portion of the study, meaning neither the parent nor the study team will know which treatment the child receives.

The child will need to be able to swallow age-appropriate oral medication.

If the child is breastfeeding and the mother is taking certain medications that could interfere with the study or harm the child, breastfeeding may need to be discontinued.

For children under one year old, the child should continue receiving the recommended vitamin D supplementation of 5 to 10 micrograms per day or as recommended by local guidelines.

2 Regular monitoring visits throughout the year

The child will attend regular study visits throughout the treatment period. The parent or legal guardian must be willing and able to attend all study visits.

At these visits, the study team will monitor the child’s safety by checking vital signs such as heart rate, blood pressure, and temperature.

The child will undergo physical examinations, including checks of the soft spots on the head called fontanelles when applicable.

Blood tests and other laboratory assessments will be performed to monitor for any changes, including a condition called hyperphosphatemia, which means higher than normal levels of phosphate in the blood.

The child will have electrocardiograms, which are tests that measure the electrical activity of the heart.

Eye examinations will be conducted to check for any ocular events or problems with the eyes.

The study team will monitor the child’s teeth formation and eruption to check for any abnormalities.

The child will undergo imaging tests, such as x-rays of both lower legs and the entire spine, to assess bone structure and look for any bone abnormalities not typically seen in achondroplasia.

Magnetic resonance imaging, a scan that uses magnets and radio waves to create detailed pictures of the inside of the body, will be used to examine the skull and brain structure.

The study team will track when the skull joints called cranial sutures and the soft spots called fontanelles close.

3 Growth and development assessments

The child’s body length will be measured regularly to calculate a Z-score, which compares the child’s growth to standard growth charts for children with achondroplasia.

The study team will measure the ratio between the upper body and lower body segments.

The ratio between head circumference and body length will be measured.

The child’s developmental progress will be assessed using milestone charts specific to achondroplasia, including social and emotional development, language and communication skills, thinking abilities, and physical movement development.

The parent or guardian will complete questionnaires about the child’s quality of life using the Infant Toddler Quality of Life assessment.

The study team will monitor for sleep apnea, a condition where breathing repeatedly stops and starts during sleep, recording how often it occurs and how severe it is.

Any surgical procedures the child undergoes will be recorded, including operations to relieve pressure on the spinal cord at the neck called cervical decompression, removal of tonsils and adenoids called adenotonsillectomy, and insertion of small tubes in the ears called tympanostomy.

4 Week 52 assessment

At week 52, which is approximately one year after starting treatment, the child will undergo a comprehensive assessment.

All measurements from the monitoring visits will be repeated, including body length, upper to lower body segment ratio, and head circumference to body length ratio.

The changes from the beginning of the study to week 52 will be calculated and compared.

The child’s body length Z-score in relation to achondroplasia growth charts will be evaluated as a key measure of treatment effect.

5 Extension period for younger children

Children who complete the initial study period may continue in an extension phase.

The extension period will continue until the child reaches three years of age, plus an additional six months.

During the extension, the child will continue receiving infigratinib treatment.

The same safety monitoring will continue, including vital signs checks, physical examinations, heart tests, imaging studies, laboratory tests, and eye examinations.

Growth measurements will continue, tracking changes in body length Z-score over time.

The ratio of upper to lower body segments and head circumference to body length will continue to be measured.

Developmental milestones and quality of life assessments will continue throughout the extension period.

The study team will continue to monitor when cranial sutures and fontanelles close.

Any surgical procedures will continue to be recorded.

Bone structure will continue to be assessed through x-rays of the lower legs and spine.

Who Can Join the Study?

The child must have a diagnosis of achondroplasia, which is a genetic condition affecting bone growth, confirmed by genetic testing. This means a laboratory test must show the specific change in the child’s genes that causes this condition.
The child must be between 0 and 32 months old, which means from birth up to 2 years and 8 months old, at the time of the first visit.
The parent or legal guardian, who is the person legally responsible for the child, must sign a document agreeing to the child’s participation in the study.
The parent or legal guardian must be willing and able to bring the child to all study visits and follow all study rules.
The parent or legal guardian must be willing and able to provide routine care for the child according to local recommendations for managing infants and young children with achondroplasia.
If the child is breastfeeding, which means receiving mother’s milk, the mother must be willing to stop taking any medication that could harm the child or affect how the study medication works in the child’s body. If the mother cannot stop taking such medication, she must be willing to stop breastfeeding the child.
The child must be able to swallow oral medication that is appropriate for their age.
If the child is younger than 1 year old, they must be receiving the recommended amount of vitamin D supplement, which is 5 to 10 micrograms per day or more, as recommended by guidelines in their country.

Who Cannot Join the Study?

The specific exclusion criteria (reasons why a patient cannot participate) have not been provided in the available study information
Generally, clinical trials may exclude patients if they have certain other medical conditions that could affect the study results or their safety
Patients taking certain medications that might interact with the study drug may not be able to participate
Women who are pregnant or breastfeeding (feeding a baby with breast milk) are typically excluded from medication studies
Patients with severe kidney or liver problems (organs that help clean the blood and process medications) may not be eligible
Those with known allergies (bad reactions) to the study medication or similar drugs may be excluded
Patients who have participated in another clinical trial recently may not be able to join
Those with certain heart conditions or abnormal heart rhythms (irregular heartbeat patterns) might be excluded
Patients who cannot follow the study requirements or attend regular visits may not be eligible

Where you can join this trial?

Verified and Recommended Sites

No sites found in this category

Verified Sites

Site Name	City	Country	Status
Oslo Universitetssykehus HF	Oslo	Norway

Other Sites

No sites found in this category

Trial status

Country	Status	Recruitment Start
Norway	Recruiting	20.11.2025
Spain	Not yet recruiting	20.11.2025

Trial locations

Investigated drugs:

Infigratinib

Infigratinib is an oral medication being tested in this clinical trial for the treatment of achondroplasia in infants and young children. Achondroplasia is a genetic condition that affects bone growth. This medication is being studied to see if it is safe and if it can help improve growth in very young children with this condition. The trial will test the medication at different dose levels to find the most appropriate and safe amount to give to children under 3 years of age.

Placebo is an inactive substance that looks like the real medication but contains no active ingredients. Some children in this trial will receive placebo instead of the actual medication so that researchers can compare the results and determine if the medication is truly effective. This helps scientists understand whether any changes seen in the children are due to the medication itself or to other factors.

Achondroplasia – Achondroplasia is a genetic disorder that affects bone growth and is the most common form of dwarfism. The condition is caused by a mutation in a gene that controls bone development, which leads to abnormal cartilage formation. Children with achondroplasia have shorter arms and legs compared to their body trunk, resulting in disproportionate short stature. The skull may be larger than average with a prominent forehead, and the bridge of the nose may appear flattened. As the child grows, the upper and lower body segments remain disproportionate, and the head circumference to body length ratio differs from typical development. Some children may experience delayed closure of the soft spots on the skull and may develop a curved spine as they grow.

Trial ID:

2024-518072-31-00

Protocol code:

QBGJ398-204

Trial Phase:

Therapeutic exploratory (Phase II)

Other Trials to Consider

#1 Clinical Trials Search in Europe

A study testing the safety and effectiveness of infigratinib compared to placebo in infants and young children with achondroplasia

What is this study about?

Who Can Join the Study?

Who Cannot Join the Study?