Novartis reports nine tumor cases in Zolgensma treated patients

Novartis says it has received nine reports of tumors in patients previously treated with its spinal muscular atrophy gene therapy Zolgensma since approval in 2019, with two cases showing evidence of vector DNA integration.

Why it matters: Regulators are now assessing the cases, and the disclosure tests how a one time gene therapy's long term safety record is monitored years after treatment.

Data as of Novartis statement shared by SMA Europe on November 5, 2026, read in full; STAT reporting of November 5, 2026 read in part (paywalled beyond its opening section), with the company's own statement used for all figures. Developing item.

Novartis has received nine reports of tumors in patients previously treated with Zolgensma, its one time gene therapy for spinal muscular atrophy, since the treatment was first approved in 2019. In two of the cases, the company says, tumors showed evidence of vector DNA integration into the patient’s DNA, a risk already listed in the product’s prescribing information, and both patients were treated and remain under monitoring.

STAT reported that seven of the instances were previously unknown and that Novartis disclosed the information to neurologists earlier this week, before an advocacy group publicised the cases on Thursday. SMA Europe said the relevant regulatory authorities are actively assessing the evidence, and Novartis said it notified health authorities in each case and will work with them on next steps. More than 6,000 patients have been treated with Zolgensma across trials, managed access programmes and commercial use.

Novartis reports nine tumor cases in Zolgensma treated patients

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