Two Zolgensma patients die of liver failure

On August 11, 2022, Novartis reported the death of two Zolgensma patients from liver failure.

Zolgensma Liver Failure Death

Zolgensma (onasemnogene abeparvovec), produced by AveXis, a Novartis company, is a gene therapy medicine, containing the active ingredient onasemnogene abeparvovec. Zolgensma has been used for the treatment of pediatric patients with spinal muscular atrophy (SMA), a devastating condition caused by genetic mutation or deletion. SMA causes lower spinal cord degeneration, muscle weakness and atrophy. SMA impacts a child’s ability to move. In severe cases, it can impact breathing or swallowing. It is a leading cause of infant mortality. Zolgensa replaces the function of a missing or nonworking survival motor neuron 1 (SMN1) gene with a new, working copy of an SMN gene.

Zolgensma patients receive intravenous (IV) infusions in a one-time treatment. The infusion (drip) lasts about 1 hour. Recipients are given corticosteroid medicines to reduce side effect risk. Worldwide, Zolgnensma has been used in the treatment of over 2,300 patients, including clinical trials and managed access programs.

Zolgensma was designated an “orphan medicine” – for use in rare diseases – by the European Medicines Agency on June 29, 2015. The U.S. Food & Drug Administration (FDA) approved Zolgensa in May 2019, for all SMA patients under 2 years of age at the time of dosing. Though questions were raised about the legitimacy of the data submitted to the FDA, Zolgensma also received a conditional marketing authorization for Europe on May 18, 2020.

In August 2022, Novartis disclosed that two cases of fatal acute liver failure were reported in pediatric patients treated with Zolgensma. The patients were ages 4 months and 28 months at the time of treatment. Both deaths occurred 6-7 weeks after a Zolgensma infusion, following the initiation of corticosteroid taper. The patients, in Russia and Kazakhstan, died of acute liver failure, a known side effect of Zolgensma. One of the children was over the age limit allowed by the FDA in the United States.

Liver toxicity is a common side effect of gene therapies like Zolgensma. Many gene therapies, including Zolgensa, rely on adeno-associated viruses (AAVs), directed at the liver, as delivery vectors. An FDA review of gene therapies found few ways to make them safer, but also noted that they are generally used to treat rare, life-threatening conditions. A 2020 paper described two cases of subacute liver failure following Zolgensma treatment.

Novartis acquired AveXis, the developer of Zolgensma, in 2018 for $8.7 billion. Novartis has indicated that it notified practitioners and will add an updated warning to the drug.