Zolgensma for Spinal Muscular Atrophy: From Approval to Present Day


Lately, there have been many newsworthy articles about Novartis and Zolgensma (onasemnogene abeparvovec-xioi).

In May 2019 the FDA approved Zolgensma, a one-time treatment for the most severe form of spinal muscular atrophy (SMA). It is one of the leading causes of infant death. CBS News reports that the drug is being sold at a cost of $2.125 million per treatment.

Data Manipulation

One month after the drug’s approval the FDA announced that it discovered that “manipulated data” had been submitted by AveXis, a subsidiary of Novartis, in its application for approval.

The FDA declared that the manipulation impacted the accuracy of data even though, as Norvatis stated, it was a minimal amount of data and pertained to animal testing and not human testing.

To be more specific, the FDA’s complaint was that AveXis knew about the data issue prior to the drug’s approval but did not report it until after Zolgensma was approved. Of course, the market reacted negatively to the news.

Novartis claims that it simply wanted to conduct a full investigation before any disclosures to the FDA.

Nevertheless, CBS reported that the FDA offered assurances that Zolgensma will retain its approval.

Two Infant Deaths

Zolgensma received FDA approval on May 24, 2019. The previous month Novartis reported a second infant death, this time in its European trial. As expected, Novartis stock plummeted.

The company reported that its findings indicated that the death occurred as a result of severe respiratory infection and neurological complications not related to Zolgensma.

Novartis was quick to point out that approximately fifty percent of infants with type 1 SMA will die or require a permanent breathing apparatus by the time they are ten months of age.

SMA and the SMA Clinical Trial

The loss of motor neurons in patients with spinal muscular atrophy (SMA) leads to muscle weakness and eventual paralysis.

In SMA, a genetic defect compromises the SMN1 gene that codes SMN, a protein responsible for the survival of motor neurons.

The first submission by Novartis to the FDA involved fifteen infants who were given Zolgensma therapy. The clinical trial was expanded to twenty-two infants with SMA Type 1.

March 2019 was the cutoff date for submission to the FDA at which time thirteen of nineteen original patients had reached the age of fourteen months without permanent ventilation. This was one of the critical endpoints of the trial.

A Very High Priced Drug

Novartis originally estimated that Zolgensma would be cost effective at around $4 million to $5 million for the one-time treatment. They indicated that the price would be determined through negotiations with medical plans.

AveXis, the developer of Zolgensma, was acquired by Novartis in 2018 for $8.7 billion. The drug has a list price of over $2 million. At this price, Zolgensma is the most expensive drug in the entire world.

In September 2019, AveXis announced that their Phase 3 trial, SPRINT, demonstrated age-appropriate milestones and long-term survival in type 1 SMA.


Rose Duesterwald

Rose Duesterwald

Rose became acquainted with Patient Worthy after her husband was diagnosed with Acute Myeloid Leukemia (AML) six years ago. During this period of partial remission, Rose researched investigational drugs to be prepared in the event of a relapse. Her husband died February 12, 2021 with a rare and unexplained occurrence of liver cancer possibly unrelated to AML.

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