Update: Market Chatter: Novartis Reports Two Confirmed Tumor Cases Linked to Neuromuscular Gene Therapy

05:48 AM EST, 11/06/2026 (MT Newswires) -- (Updates with Novartis' response in the fourth and fifth paragraphs and latest stock moves in the sixth paragraph.) Novartis (NVS) said testing has linked two tumor cases to its Zolgensma gene therapy, which treats spinal muscular atrophy, a rare genetic disease that causes progressive muscle weakness, Bloomberg reported Friday. Since its approval in 2019, nine tumor cases have been reported in patients treated with Zolgensma, the report said. Novartis told Bloomberg it continues to monitor safety reports and assess all reported cases, though it has not confirmed the type or location of the tumors. The drug's existing safety information warns of a potential tumor risk associated with the therapy's insertion into patients' DNA, Bloomberg reported. In a statement, Novartis said that more than 6,000 patients have been treated with Zolgensma in various clinical trials, other programs, and commercial treatment, of which the company has received nine reports of tumors, with two showing evidnece of being linked to the drug. "The patients underwent treatment and continue to be monitored," the company said. "The potential risk of tumors due to vector integration is currently included in the Zolgensma prescribing information." Shares of the company were down 1.5% in recent premarket trading. (Market Chatter news is derived from conversations with market professionals globally. This information is believed to be from reliable sources but may include rumor and speculation. Accuracy is not guaranteed.)