The U.S. Food and Drug Administration (FDA) has for the first time authorized the use of the gene therapy Itvisma (onasemnogene abeparvovec-bre) to treat spinal muscular atrophy (SMA) in adults and children over the age of two with a confirmed SMN1 gene mutation. This is the first approval of its kind to extend gene therapy to a broader age group, unlike the previously available Zolgensma, which was intended only for infants under two years old.
Itvisma is administered as a single dose into the cerebrospinal fluid and does not require weight-based dosing calculations. This approach simplifies treatment and increases its precision. The drug is based on an AAV vector, a reliable gene delivery system with minimal side effects. Clinical trials showed that the drug effectively stops disease progression in children from the age of two. For adults, it also opens a new treatment path, although with some limitations in chronic conditions.
SMA is a severe inherited disease in which a mutation in the SMN1 gene disrupts the production of a protein that is critical for motor neurons. Without treatment, the disease leads to severe muscle atrophy, complete loss of mobility, and premature death. For the first time, adult patients with a diagnosis that until recently meant irreversible disability now have access to effective treatment.
