Active not recruitingPHASE2INTERVENTIONAL

Larotrectinib in Treating Patients With Previously Untreated TRK Fusion Solid Tumors and TRK Fusion Relapsed Acute Leukemia

This study is for children and young people (up to age 30) with certain types of cancer that have a special change in their genes called a TRK fusion. We're looking at a new medicine called larotrectinib. This medicine aims to block the growth of cancer cells that have this specific gene change. The study will help us understand how well larotrectinib works in treating these cancers and what its side effects might be. It includes different types of solid tumors, like a rare muscle cancer called infantile fibrosarcoma, and a type of blood cancer called acute leukemia that has come back or not responded to other treatments. The goal is to see if this medicine can shrink tumors or put leukemia into remission.

At a glance

Status

Active not recruiting

Phase

PHASE2

Sponsor

Children's Oncology Group

Enrolment target

Start

25 Oct 2019

Estimated completion

25 Jul 2027

Central Nervous System Neoplasm Infantile Fibrosarcoma Recurrent Acute Leukemia Refractory Acute Leukemia Solid Neoplasm

Results

Results from this study

Posted December 2025

Results have been published for this study.

Primary outcome

Objective Response Rate (ORR) of Children With Infantile Fibrosarcoma (IFS) Treated With Neoadjuvant Larotrectinib Prior to Local Control

A responder is defined as a patient who achieves a best response of partial response (PR) or complete response (CR) on the study. Response rates will be calculated as the percent of evaluable patients who are responders, and confidence intervals will be constructed accounting for the two-stage design.

Full results on the registry

What is this study about?

This study is looking into a medicine called larotrectinib for children and young people up to the age of 30 who have certain cancers. What makes these cancers special is that they all have a particular gene change, known as a 'TRK fusion'. This change can make cancer cells grow more easily. Larotrectinib is designed to specifically target and block the processes driven by these TRK fusions, which could stop the cancer cells from growing.

The study aims to discover how effective larotrectinib is at treating different types of TRK fusion cancers. This includes solid tumors, like a rare muscle cancer that babies can get called infantile fibrosarcoma, and other solid tumors that might be in the brain or other parts of the body. It also includes a type of blood cancer called acute leukemia, specifically when it has returned or hasn't responded well to other treatments. Researchers are hoping to see if the medicine can shrink tumors, put the leukemia into remission, and improve the patient's health.

Another important part of the study is to carefully look at any side effects larotrectinib might cause. By gathering this information, doctors can learn more about how to use this medicine safely and effectively for young people with these specific cancers. Understanding both the benefits and any potential downsides is crucial for future treatments.

Key takeaways

This study is for children and young people up to 30 years old.
It targets specific cancers with a 'TRK fusion' gene change.
The medicine, larotrectinib, aims to stop cancer cell growth.
It covers solid tumors (like infantile fibrosarcoma) and certain acute leukemias.
Researchers will check how well it works and look for side effects.

Who may be eligible?

This study is for children and young people up to 30 years old. To join, your cancer must have a specific gene change called a TRK fusion, which your doctor would have tested for.

The study is divided into different groups. One group is for babies and young children with a rare type of muscle cancer called infantile fibrosarcoma. Another group is for those with other types of solid tumors, such as brain tumours, as long as they also have the TRK fusion.

There's also a group for patients with a type of blood cancer called acute leukemia, but only if it's come back after previous treatment or hasn't responded to other medicines, and also has the TRK fusion. Your doctor will be able to check if your specific cancer and gene changes mean you could be part of this study.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 30 years old or younger?
Has your doctor confirmed that your cancer has a 'TRK fusion' gene change?
Do you have infantile fibrosarcoma with a TRK fusion?
Do you have another type of solid tumor with a TRK fusion (excluding some specific high-grade brain tumors)?
Do you have acute leukemia with a TRK fusion that has come back or not responded to prior treatment?

Answer every question to see your result.

What does participation involve?

If you join this study, you would take the medicine larotrectinib, likely in pill form. You'll have regular hospital visits for check-ups, blood tests, and scans to monitor how the medicine is working and to watch for any side effects. These visits will be more frequent at the beginning and then might become less often over time.

The study team will monitor your health closely throughout. The total length of time you'll be part of the study can vary depending on how you respond to the treatment. There will also be follow-up appointments after you stop taking the medicine to ensure your health continues to be monitored. Your doctor will explain all the specific appointments and tests involved.

Potential risks and benefits

Participating in this study might offer the benefit of receiving a new medicine that could help treat your cancer, especially if other treatments haven't worked or if your cancer has specific gene changes. However, like all medicines, larotrectinib can have side effects, which the study doctors will carefully monitor. You will be told about all known possible risks before you decide to join. Remember, you can choose to leave the study at any time, for any reason, without it affecting your usual medical care.

Locations (80)

Children's Hospital of Alabama
Verified postcode
Birmingham, United States
Arkansas Children's Hospital
Verified postcode
Little Rock, United States
Kaiser Permanente Downey Medical Center
Verified postcode
Downey, United States
Children's Hospital Los Angeles
Verified postcode
Los Angeles, United States
Kaiser Permanente-Oakland
Verified postcode
Oakland, United States
Children's Hospital of Orange County
Verified postcode
Orange, United States
UCSF Medical Center-Mission Bay
Verified postcode
San Francisco, United States
Children's Hospital Colorado
Verified postcode
Aurora, United States
Rocky Mountain Hospital for Children-Presbyterian Saint Luke's Medical Center
Verified postcode
Denver, United States
Yale University
Verified postcode
New Haven, United States
Alfred I duPont Hospital for Children
Verified postcode
Wilmington, United States
MedStar Georgetown University Hospital
Verified postcode
Washington D.C., United States

Common questions

What is a 'TRK fusion'?

It's a specific change in your genes within cancer cells that can make them grow. Larotrectinib is designed to target this change.

Is larotrectinib a new type of treatment?

Yes, it is a newer type of medicine that specifically targets cancers with TRK gene fusions.

Will I have to stay in the hospital?

Most likely, you won't need to stay in the hospital for the treatment itself, but you will have regular hospital visits for check-ups and tests.

What if the medicine doesn't work for me?

The study team will monitor your progress closely. If the medicine isn't working or if side effects are too severe, your doctor will discuss other treatment options with you.

Can I continue with my normal activities?

This will depend on your health and how you respond to the treatment. Your doctor will advise you on what activities are safe for you.