FDA Fails to Update Labeling Despite Confirmed Tumor Risks in Zolgensma Patients

Novartis confirmed that nine children treated with its SMA gene therapy Zolgensma were diagnosed with tumors. In two of these cases, pathological analysis found that the gene therapy's viral vector inserted itself into a patient's chromosomes, a process called insertional mutagenesis, which was likely the cause of the tumor. Despite this, the FDA label has not been updated to reflect these confirmed cases, a risk that Novartis's own prescribing information previously described as theoretical.

The confirmed cases raise urgent questions about post-market surveillance for gene therapies. The failure of the FDA to update the warning label despite confirmed risks associated with a blockbuster drug affects the regulatory environment for advanced therapies.