This study is for children and teens aged 3 to 18 years with a condition called methylmalonic acidemia (MMA). MMA is a rare illness where the body has trouble breaking down certain proteins, leading to serious health issues. This research looks at an investigational medication that uses gene transfer therapy to possibly help with MMA.
Key Points:
- Study Length: Participants will be followed closely for safety for 1 year, and then checked yearly for 4 additional years.
- Visits: Regular check-ups are required, especially in the first year. This includes multiple visits for treatment doses.
- Eligibility: Participants must have severe MMA, not have had an organ transplant, and meet other health criteria.
Participants must be able to take part in study activities and follow certain lifestyle guidelines. This study involves two types of treatments given together to see if they can safely help reduce MMA symptoms.

