As reported on Pharmaceutical Technology, the European Commission has approved Novartis’ gene replacement therapy Itvisma (onasemnogene abeparvovec) for the treatment of children aged two years and older, adolescents, and adults with 5q spinal muscular atrophy (SMA) who carry bi-allelic mutations in the survival motor neuron 1 (SMN1) gene.
The decision broadens treatment options for patients living with SMA and makes Itvisma the only gene replacement therapy currently authorized in the European Union for this expanded patient population.
How the Therapy Works
SMA is a rare genetic neuromuscular disorder caused by insufficient production of the SMN protein due to defects in the SMN1 gene. Itvisma is designed to address the underlying genetic cause of the disease by delivering a working copy of the SMN1 gene, helping the body produce the protein needed for motor neuron function.
The therapy is administered as a single intrathecal injection and uses a fixed-dose approach, eliminating the need for dosing adjustments based on a patient’s age or weight.
Clinical Data Supporting Approval
The European approval is based on findings from several clinical studies, including the pivotal STEER trial, the Phase IIIb STRENGTH study, and the Phase I/II STRONG trial.
Results from the STEER study demonstrated a significant improvement in motor function, with treated patients achieving a 2.39-point gain on the Hammersmith Functional Motor Scale. These improvements were sustained throughout the 52-week evaluation period.
Data from both STEER and STRENGTH also indicated meaningful clinical benefits in a broad range of patients, including those who had previously received SMA therapies as well as individuals who had not undergone treatment before enrolling in the studies.
Addressing Unmet Needs in SMA
Commenting on the approval, Patrick Horber, President of Novartis International, said the decision represents an important step forward for the SMA community. He noted that expanding access to a one-time gene replacement treatment for older children, teenagers, and adults could help address longstanding gaps in care for patients beyond infancy.
Safety Profile
The most frequently reported adverse events associated with Itvisma include upper respiratory tract infections, fever, vomiting, headache, and elevated liver enzyme levels.
Novartis’ SMA Gene Therapy Portfolio
Novartis maintains exclusive worldwide rights covering both intravenous and intrathecal administration of AAV9-based gene therapies for spinal muscular atrophy, reinforcing the company’s position in the development of genetic treatments for the disease.
The latest authorization marks a significant expansion in access to gene therapy for SMA patients across Europe and reflects growing clinical evidence supporting the use of SMN1 gene replacement beyond the pediatric population traditionally targeted by such treatments.
