A Study to Evaluate How Apitegromab Works in Subjects Who Are Less Than 2 Years Old and Have Spinal Muscular Atrophy

To join this study, a child must be under two years old and have a confirmed diagnosis of 5q autosomal recessive SMA. They also need to have received, or still be receiving, an approved treatment for SMA. The child's overall health and growth will be checked to make sure they are well enough to take part, and they must show some delays in their movement skills related to SMA.

There are also some reasons why a child might not be able to join. For instance, if they have major bone problems like severe curvature of the spine (scoliosis) or stiff joints that would make it hard to measure their movement, or if they've had recent major surgery related to these issues. Children who need a permanent feeding tube for most of their meals, or have other physical limitations that would stop them from doing movement tests, also can't take part.

If your child takes part, they will receive doses of the study medicine, apitegromab. This study is "double-blind," meaning neither you nor the study doctors will know if your child is receiving the active medicine or a placebo (a dummy medicine) – this helps ensure fair results. Your child will have regular visits to the clinic where doctors will check their health, take blood samples to see how the medicine is working in their body, and perform tests to assess their muscle function and development, such as movement tests. The total duration of the study will involve several visits over a period of time, with ongoing follow-up to monitor your child's progress and safety.