Novartis confirms tumors in 9 children given Zolgensma

Zolgensma is a one-time gene therapy for babies with a disease that used to kill most of them young. Novartis said Thursday that nine of the children who got it later developed tumors. Seven of those cases had never been made public until patient advocates started asking questions. In two children, the company confirmed the therapy's own virus had spliced itself into their DNA and triggered the tumor.

This is exactly the kind of risk scientists worried about when gene therapy first arrived. These treatments work by sneaking a virus into a patient's cells to deliver a fixed gene. Usually that virus just delivers its cargo and fades away. But sometimes, rarely, it inserts itself into the body's own DNA instead. If it lands in the wrong spot, it can switch on a gene that causes cancer. Zolgensma has been given to more than 6,000 children since 2019. For most of them, it was the only shot at treating a disease that's otherwise often fatal in infancy. Nine tumors out of that many patients is still rare. But most of it stayed quiet until pressure from families forced it into the open. That's its own problem, separate from the safety numbers.

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Will regulators force Novartis to update Zolgensma's warning label now? Right now the FDA's own paperwork still calls the DNA-integration risk 'theoretical.' Novartis just confirmed it happened to two real children. Parents who are weighing this treatment for a newborn deserve to know the real odds, not an outdated word. The bigger question reaches past this one drug. A wave of gene therapies is heading toward approval that works the same way. They use a virus to deliver a new gene. If regulators and drug companies stay slow to disclose side effects like this, families pay the price. They'll keep making life-or-death decisions without the full picture.