NS-089/NCNP-02-201 in Boys With Duchenne Muscular Dystrophy (DMD)

To join this study, boys must be between 4 and 14 years old. They need to have a confirmed diagnosis of Duchenne muscular dystrophy (DMD) caused by a specific genetic change (mutation) that can be treated by 'exon 44 skipping'. It's also important that they can walk by themselves without any walking aids and can complete a specific walking test quickly.

Participants must have been on a steady dose of steroid medication for at least three months before starting the study and expect to continue that dose throughout. There are also some reasons why someone might not be able to join. For example, if they have certain heart problems, have used particular medications or other experimental treatments recently, or have had surgery in the last three months.

They also can't have participated in a previous study of this exact medicine (NS-089/NCNP-02) or received other similar 'exon skipping' treatments in the past year. There are other criteria too, so the study team will check everything carefully.

If you decide to take part, the study involves weekly visits to receive the medicine, NS-089/NCNP-02, through a drip into a vein (IV infusion). The total duration of your involvement will depend on which part of the study you join.

Before treatment starts, there will be screening visits to ensure you meet all the requirements. During the study, you'll have regular check-ups, assessments of your muscle strength and movement (like walking tests), and possibly blood tests to see how the medicine is affecting you. All these visits and tests are designed to monitor your health and how the medicine is working. The study is divided into two parts, so some participants will be involved for longer than others.