Phase I Study of 131-I mIBG Followed by Nivolumab & Dinutuximab Beta Antibodies in Children With Relapsed/Refractory Neuroblastoma

This study is open to children aged 1 year and older who have high-risk neuroblastoma that has come back or has not improved with standard treatments. The child's cancer must also show up clearly on a specific scan called an mIBG scan, which shows that the targeted radiation therapy will be able to reach the tumours.

To safely take part, children must be well enough to carry out everyday activities and have vital organs that are working reasonably well. Doctors will check blood counts, kidney, liver, heart, and lung function. Children must also have had a break from previous intense treatments, such as stem cell transplants or other immunotherapies, to allow their bodies time to recover.

Children cannot join if the cancer has spread into the main tissue of the brain and is active on scans, or if their organs are not strong enough to handle the trial medicines safely. A doctor will carefully review all previous medical records to confirm whether a child is eligible.

Taking part involves receiving treatment in a specialist hospital under close medical care. Before beginning, children will undergo baseline checks, including blood tests, heart scans, breathing tests, and imaging scans. A central line (a soft tube placed in a vein) will be needed to give the medicines smoothly and take blood samples without repeated needle sticks.

Children will receive the 131-I mIBG radiation therapy first, followed by the immunotherapy drugs given through a drip. Because the trial uses an adaptive approach, treatment is divided into small groups to check safety at each stage. Families can expect frequent hospital visits, regular blood tests, and routine scans over at least 12 weeks of active treatment. The research team will track each child's health closely throughout the process, and total follow-up will continue for several months to monitor recovery and long-term wellbeing.