Novartis cites cases of previously unknown tumors possibly tied to its SMA gene therapy

Novartis has disclosed seven previously unreported cases in which tumors were found in children treated with Zolgensma, its gene therapy for spinal muscular atrophy, according to STAT News. The company cited these case reports in connection with the therapy, though the reporting describes the tumors as “possibly tied to” the treatment rather than confirmed as caused by it.

Zolgensma uses a viral vector to deliver a functional copy of a gene to patients, most of them infants, with spinal muscular atrophy, a disease that otherwise causes progressive muscle weakness and, in its most severe forms, early death. The therapy has been administered to thousands of children since its approval.

STAT News reports that the seven tumor cases had not previously been disclosed. The story does not specify the types of tumors involved, their outcomes, or the mechanism by which the therapy might be implicated, and this bulletin does not speculate beyond what the source reports.

Gene therapies work by introducing genetic material directly into a patient’s cells, and regulators have long flagged insertional mutagenesis, the risk that a vector’s integration into the genome could disrupt normal gene function, as a theoretical long-term concern for this class of treatment. Novartis’s disclosure of these cases adds new data to that ongoing question.

Further detail, including any response from Novartis or regulators, was not available in the cited report at time of writing.